10-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q

ý QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2013

or

¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from ________  to ________                     

Commission File No. 0-19731

GILEAD SCIENCES, INC.

(Exact Name of Registrant as Specified in Its Charter)

Delaware	94-3047598
(State or Other Jurisdiction of Incorporation or Organization)	(IRS Employer Identification No.)
333 Lakeside Drive, Foster City, California	94404
(Address of principal executive offices)	(Zip Code)

650-574-3000

Registrant’s Telephone Number, Including Area Code

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  ý    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).     Yes  ý    No  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer  ý    Accelerated  filer  ¨    Non-accelerated filer  ¨    Smaller reporting company  ¨

(Do not check if a smaller reporting company)

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  ý

Number of shares outstanding of the issuer’s common stock, par value $0.001 per share, as of April 26, 2013: 1,525,355,825

GILEAD SCIENCES, INC.

INDEX

PART I.	FINANCIAL INFORMATION		2
	Item 1.	Consolidated Financial Statements	2
		Consolidated Balance Sheets at March 31, 2013 and December 31, 2012	2
		Consolidated Statements of Income for the Three Months Ended March 31, 2013 and 2012	3
		Consolidated Statements of Comprehensive Income for the Three Months Ended March 31, 2013 and 2012	4
		Consolidated Statements of Cash Flows for the Three Months Ended March 31, 2013 and 2012	5
		Notes to Consolidated Financial Statements	6
	Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	23
	Item 3.	Quantitative and Qualitative Disclosures About Market Risk	31
	Item 4.	Controls and Procedures	32
PART II.	OTHER INFORMATION		33
	Item 1.	Legal Proceedings	33
	Item 1A.	Risk Factors	37
	Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	52
	Item 3.	Defaults Upon Senior Securities	52
	Item 4.	Mine Safety Disclosures	52
	Item 5.	Other Information	52
	Item 6.	Exhibits	53
SIGNATURES			62

We own or have rights to various trademarks, copyrights and trade names used in our business, including the following: GILEAD^®, GILEAD SCIENCES^®, STRIBILD^®, COMPLERA^®, EVIPLERA^®, TRUVADA^®, VIREAD^®, HEPSERA^®, AMBISOME^®, EMTRIVA^®, VISTIDE^®, LETAIRIS^®, VOLIBRIS^®, RANEXA^®, CAYSTON^® and RAPISCAN^®. ATRIPLA^® is a registered trademark belonging to Bristol-Myers Squibb & Gilead Sciences, LLC. LEXISCAN^® is a registered trademark belonging to Astellas U.S. LLC. MACUGEN^® is a registered trademark belonging to Eyetech, Inc. SUSTIVA^® is a registered trademark of Bristol-Myers Squibb Pharma Company. TAMIFLU^® is a registered trademark belonging to Hoffmann-La Roche Inc. This report also includes other trademarks, service marks and trade names of other companies.

PART I. FINANCIAL INFORMATION

ITEM I. CONSOLIDATED FINANCIAL STATEMENTS

GILEAD SCIENCES, INC.

CONSOLIDATED BALANCE SHEETS

(in thousands, except per share amounts)

	March 31, 2013		December 31, 2012
	(unaudited)
Assets
Current assets:
Cash and cash equivalents	$	1,863,972	$	1,803,694
Short-term marketable securities	78,804		58,556
Accounts receivable, net	1,945,189		1,751,388
Inventories	1,799,618		1,744,982
Deferred tax assets	211,938		262,641
Prepaid taxes	411,117		348,420
Prepaid expenses	134,711		102,364
Other current assets	217,748		84,302
Total current assets	6,663,097		6,156,347
Property, plant and equipment, net	1,125,794		1,100,259
Long-term portion of prepaid royalties	179,207		175,790
Long-term deferred tax assets	139,663		131,107
Long-term marketable securities	688,254		719,836
Intangible assets, net	12,077,548		11,736,393
Goodwill	1,188,157		1,060,919
Other long-term assets	149,948		159,187
Total assets	$	22,211,668	$	21,239,838
Liabilities and Stockholders’ Equity
Current liabilities:
Accounts payable	$	1,356,372	$	1,327,339
Accrued government rebates	875,751		745,148
Accrued compensation and employee benefits	152,663		236,716
Income taxes payable	19,240		13,403
Other accrued liabilities	819,009		674,762
Deferred revenues	124,369		103,162
Current portion of long-term debt and other obligations, net	942,811		1,169,490
Total current liabilities	4,290,215		4,270,020
Long-term deferred revenues	32,204		20,532
Long-term debt, net	7,054,796		7,054,555
Long-term income taxes payable	110,250		115,822
Long-term deferred tax liabilities	118,403		10,190
Other long-term obligations	213,327		217,850
Commitments and contingencies (Note 10)
Stockholders’ equity:
Preferred stock, par value $0.001 per share; 5,000 shares authorized; none outstanding	—		—
Common stock, par value $0.001 per share; 2,800,000 shares authorized; 1,524,383 and 1,519,163 shares issued and outstanding (1)	760		760
Additional paid-in capital	5,829,126		5,649,850
Accumulated other comprehensive income (loss)	20,806		(45,615		)
Retained earnings	4,301,539		3,704,744
Total Gilead stockholders’ equity	10,152,231		9,309,739
Noncontrolling interest	240,242		241,130
Total stockholders’ equity	10,392,473		9,550,869
Total liabilities and stockholders’ equity	$	22,211,668	$	21,239,838

⁽¹⁾ The number of shares for all periods presented reflects the two-for-one stock split in the form of a stock dividend declared on December 10, 2012 which took effect on January 25, 2013.

See accompanying notes.

2

GILEAD SCIENCES, INC.

CONSOLIDATED STATEMENTS OF INCOME

(unaudited)

(in thousands, except per share amounts)

	Three Months Ended
	March 31,
	2013			2012
Revenues:
Product sales	$	2,393,568		$	2,208,342
Royalty revenues	134,407			71,105
Contract and other revenues	3,660			3,002
Total revenues	2,531,635			2,282,449
Costs and expenses:
Cost of goods sold	634,448			580,931
Research and development	497,632			458,211
Selling, general and administrative	374,296			443,121
Total costs and expenses	1,506,376			1,482,263
Income from operations	1,025,259			800,186
Interest expense	(81,787		)	(97,270		)
Other income (expense), net	(3,324		)	(34,085		)
Income before provision for income taxes	940,148			668,831
Provision for income taxes	222,438			231,300
Net income	717,710			437,531
Net loss attributable to noncontrolling interest	4,476			4,425
Net income attributable to Gilead	$	722,186		$	441,956
Net income per share attributable to Gilead common stockholders—basic (1)	$	0.47		$	0.29
Shares used in per share calculation—basic (1)	1,521,372			1,512,572
Net income per share attributable to Gilead common stockholders—diluted (1)	$	0.43		$	0.28
Shares used in per share calculation—diluted (1)	1,665,060			1,554,776

⁽¹⁾ Net income per share and the number of shares used in the per share calculations for all periods presented reflect the two-for-one stock split in the form of a stock dividend declared on December 10, 2012 which took effect on January 25, 2013.

See accompanying notes.

3

GILEAD SCIENCES, INC.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(unaudited)

(in thousands)

	Three Months Ended
	March 31,
	2013			2012
Net income	$	717,710		$	437,531
Other comprehensive income (loss):
Net foreign currency translation gain (loss), net of tax	(8,956		)	4,897
Available-for-sale securities:
Net unrealized gain (loss), net of tax impact of $(1,016) and $266	1,785			(463		)
Reclassifications to net income, net of tax impact of $(9) and $(519)	(17		)	30,600
Net change	1,768			30,137
Cash flow hedges:
Net unrealized gain (loss), net of tax impact of $(1,849) and $1,802	74,060			(48,816		)
Reclassification to net income, net of tax impact of $(11) and $(400)	(451		)	(10,827		)
Net change	73,609			(59,643		)
Other comprehensive income (loss)	66,421			(24,609		)
Comprehensive income	784,131			412,922
Comprehensive loss attributable to noncontrolling interest	4,476			4,425
Comprehensive income attributable to Gilead	$	788,607		$	417,347

See accompanying notes.

4

GILEAD SCIENCES, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(unaudited)

(in thousands)

	Three Months Ended
	March 31,
	2013			2012
Operating Activities:
Net income	$	717,710		$	437,531
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation expense	23,973			19,710
Amortization expense	50,353			46,457
Stock-based compensation expense	61,767			48,731
Excess tax benefits from stock-based compensation	(40,746		)	(23,304		)
Tax benefits from employee stock plans	38,905			18,153
Deferred income taxes	39,301			51,385
Other	8,262			13,767
Changes in operating assets and liabilities:
Accounts receivable, net	(231,781		)	(196,531		)
Inventories	(57,109		)	(26,833		)
Prepaid expenses and other assets	(187,304		)	(75,176		)
Accounts payable	30,792			107,652
Income taxes payable	12,056			(99,151		)
Accrued liabilities	173,042			110,402
Deferred revenues	32,880			20,176
Net cash provided by operating activities	672,101			452,969
Investing Activities:
Purchases of marketable securities	(62,604		)	—
Proceeds from sales of marketable securities	65,985			56,719
Proceeds from maturities of marketable securities	6,862			—
Purchases of other investments	—			(25,000		)
Acquisitions, net of cash acquired	(378,645		)	(10,751,636		)
Capital expenditures	(38,854		)	(23,199		)
Net cash used in investing activities	(407,256		)	(10,743,116		)
Financing Activities:
Proceeds from debt financing, net of issuance costs	—			2,144,733
Proceeds from convertible note hedges	100,771			—
Proceeds from issuances of common stock	86,049			132,530
Repurchases of common stock	(82,239		)	(20,770		)
Repayments of debt financing	(347,896		)	(350,000		)
Repayments of other long-term obligations	(20		)	(612		)
Excess tax benefits from stock-based compensation	40,746			23,304
Contributions from (distributions to) noncontrolling interest	3,588			(73,595		)
Net cash provided by (used in) financing activities	(199,001		)	1,855,590
Effect of exchange rate changes on cash	(5,566		)	2,722
Net change in cash and cash equivalents	60,278			(8,431,835		)
Cash and cash equivalents at beginning of period	1,803,694			9,883,777
Cash and cash equivalents at end of period	$	1,863,972		$	1,451,942

See accompanying notes.

5

GILEAD SCIENCES, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The accompanying unaudited Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles for interim financial information. The financial statements include all adjustments (consisting only of normal recurring adjustments) that the management of Gilead Sciences, Inc. (Gilead, we or us) believes are necessary for a fair presentation of the periods presented. These interim financial results are not necessarily indicative of results expected for the full fiscal year or for any subsequent interim period.

The accompanying Consolidated Financial Statements include the accounts of Gilead, our wholly-owned subsidiaries and our joint ventures with Bristol-Myers Squibb Company (BMS), for which we are the primary beneficiary. We record a noncontrolling interest in our Consolidated Financial Statements to reflect BMS’s interest in the joint ventures. All intercompany transactions have been eliminated. The Consolidated Financial Statements include the results of companies acquired by us from the date of each acquisition for the applicable reporting periods.

The accompanying Consolidated Financial Statements and related financial information should be read in conjunction with the audited Consolidated Financial Statements and the related notes thereto for the year ended December 31, 2012, included in our Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (SEC).

On January 25, 2013, we completed a two-for-one stock split in the form of a stock dividend to stockholders of record as of January 7, 2013, as declared on December 10, 2012. Accordingly, all share and per share amounts for all periods presented in these Consolidated Financial Statements and notes have been adjusted retroactively to reflect this stock split.

Significant Accounting Policies, Estimates and Judgments

The preparation of these Consolidated Financial Statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures. On an ongoing basis, management evaluates its significant accounting policies or estimates. We base our estimates on historical experience and on various market specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ significantly from these estimates.

Net Income Per Share Attributable to Gilead Common Stockholders

Basic net income per share attributable to Gilead common stockholders is calculated based on the weighted-average number of shares of our common stock outstanding during the period. Diluted net income per share attributable to Gilead common stockholders is calculated based on the weighted-average number of shares of our common stock outstanding and other dilutive securities outstanding during the period. The potential dilutive shares of our common stock resulting from the assumed exercise of outstanding stock options, performance shares and the assumed exercise of warrants relating to the convertible senior notes due in May 2013 (May 2013 Notes), May 2014 (May 2014 Notes) and May 2016 (May 2016 Notes) (collectively, the Convertible Notes) are determined under the treasury stock method.

Because the principal amount of the Convertible Notes will be settled in cash, only the conversion spread relating to the Convertible Notes is included in our calculation of diluted net income per share attributable to Gilead common stockholders. Our common stock resulting from the assumed settlement of the conversion spread of the Convertible Notes has a dilutive effect when the average market price of our common stock during the period exceeds the conversion price of $19.05 for the May 2013 Notes, $22.54 for the May 2014 Notes and $22.71 for the May 2016 Notes.

During the three months ended March 31, 2013 and 2012, the average market price of our common stock exceeded the conversion prices of the Convertible Notes and the dilutive effects are included in the accompanying table. During the three months ended March 31, 2013, a portion of the Convertible Notes were converted and as a result, we have only considered their impact for the period they were outstanding.

Warrants relating to the Convertible Notes have a dilutive effect when the average market price of our common stock during the period exceeds the warrants’ exercise price of $26.95 for the May 2013 Notes, $28.38 for the May 2014 Notes and $30.05 for the May 2016 Notes. During the three months ended March 31, 2013, the average market price of our common stock exceeded the warrants' exercise prices relating to the Convertible Notes and the dilutive effect is included in the accompanying table. During the three months ended March 31, 2012, the average market price of our common stock did not exceed the

6

warrants’ exercise prices relating to any of the Convertible Notes; therefore, these warrants did not have a dilutive effect on our net income per share for that period.

Stock options to purchase approximately 1.3 million and 21.8 million weighted-average shares of our common stock were outstanding during the three months ended March 31, 2013 and 2012, respectively, but were not included in the computation of diluted net income per share attributable to Gilead common stockholders because their effect was antidilutive.

The following table is a reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share attributable to Gilead common stockholders (in thousands):

	Three Months Ended
	March 31,
	2013		2012
Numerator:
Net income attributable to Gilead	$	722,186	$	441,956
Denominator:
Weighted-average shares of common stock outstanding used in the calculation of basic net income per share attributable to Gilead common stockholders	1,521,372		1,512,572
Effect of dilutive securities:
Stock options and equivalents	36,812		29,746
Conversion spread related to the May 2013 Notes	10,703		6,846
Conversion spread related to the May 2014 Notes	25,554		3,010
Conversion spread related to the May 2016 Notes	25,140		2,602
Warrants related to the Convertible Notes	45,479		—
Weighted-average shares of common stock outstanding used in the calculation of diluted net income per share attributable to Gilead common stockholders	1,665,060		1,554,776

Concentrations of Risk

We are subject to credit risk from our portfolio of cash equivalents and marketable securities. Under our investment policy, we limit amounts invested in such securities by credit rating, maturity, industry group, investment type and issuer, except for securities issued by the U.S. government. We are not exposed to any significant concentrations of credit risk from these financial instruments. The goals of our investment policy, in order of priority, are as follows: safety and preservation of principal and diversification of risk; liquidity of investments sufficient to meet cash flow requirements; and a competitive after-tax rate of return.

We are also subject to credit risk from our accounts receivable related to our product sales. The majority of our trade accounts receivable arises from product sales in the United States and Europe.

As of March 31, 2013, our accounts receivable in Southern Europe, specifically Greece, Italy, Portugal and Spain, totaled approximately $849.6 million, of which $348.5 million were greater than 120 days past due and $114.1 million were greater than 365 days past due. To date, we have not experienced significant losses with respect to the collection of our accounts receivable. We believe that our allowance for doubtful accounts was adequate at March 31, 2013.

Recent Accounting Pronouncements

In January 2013, the Financial Accounting Standards Board (FASB) issued an update to clarify the scope of disclosures for offsetting assets and liabilities. The update was effective for us beginning in the first quarter of 2013 and was applied retrospectively for all comparative periods presented. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

In February 2013, the FASB issued a new standard to improve the reporting of reclassification adjustments out of accumulated other comprehensive income (OCI). The update requires disclosure of amounts reclassified out of accumulated OCI by component. In addition, if the amount reclassified is required to be reclassified to net income in its entirety in the same reporting period, an entity is required to present significant amounts reclassified out of accumulated OCI by the respective line items of net income. The updated standard was effective for us beginning in the first quarter of 2013. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

7

In February 2013, the FASB also issued an update to the existing standard for liabilities. The update provides guidance for the recognition, measurement and disclosure of obligations resulting from joint and several liability arrangements. For obligations for which the total amount is fixed at the reporting date, an entity will be required to measure those obligations as the sum of the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. Such entities will also be required to disclose the nature, amount and other significant information about the obligations. This guidance will become effective for us beginning in the first quarter of 2014. We are evaluating the financial statement impact of this guidance. Currently, we do not expect that adopting this update will have a material impact on our Consolidated Financial Statements.

2. FAIR VALUE MEASUREMENTS

We determine the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:

• Level 1 inputs which include quoted prices in active markets for identical assets or liabilities;

• Level 2 inputs which include observable inputs other than Level 1 inputs, such as quoted prices for similar assets or liabilities; quoted prices for identical or similar assets or liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability. For our marketable securities, we review trading activity and pricing as of the measurement date. When sufficient quoted pricing for identical securities is not available, we use market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data; and

• Level 3 inputs which include unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the underlying asset or liability. Level 3 assets and liabilities include those whose fair value measurements are determined using pricing models, discounted cash flow methodologies or similar valuation techniques and significant management judgment or estimation.

Our financial instruments consist principally of cash and cash equivalents, marketable securities, accounts receivable, foreign currency exchange forward and option contracts, accounts payable and short-term and long-term debt. Cash and cash equivalents, marketable securities and foreign currency exchange contracts that hedge accounts receivable and forecasted sales are reported at their respective fair values on our Consolidated Balance Sheets. Short-term and long-term debt are reported at their amortized cost on our Consolidated Balance Sheets. The remaining financial instruments are reported on our Consolidated Balances Sheets at amounts that approximate current fair values.

The fair values of our Convertible Notes and senior unsecured notes were determined using Level 2 inputs based on their quoted market values. The following table summarizes the carrying values and fair values of the Convertible Notes and senior unsecured notes (in thousands):

		March 31, 2013				December 31, 2012
Type of Borrowing	Description	Carrying Value		Fair Value		Carrying Value		Fair Value
Convertible Senior	May 2013 Notes	$	342,759	$	825,330	$	419,433	$	815,297
Convertible Senior	May 2014 Notes	1,211,072		2,696,870		1,210,213		2,040,363
Convertible Senior	May 2016 Notes	1,156,632		2,704,726		1,157,692		2,110,938
Senior Unsecured	April 2021 Notes	993,138		1,133,650		992,923		1,146,990
Senior Unsecured	December 2014 Notes	749,473		771,398		749,394		772,650
Senior Unsecured	December 2016 Notes	699,152		749,784		699,095		748,902
Senior Unsecured	December 2021 Notes	1,247,501		1,405,125		1,247,428		1,420,725
Senior Unsecured	December 2041 Notes	997,828		1,208,000		997,810		1,252,090

8

The following table summarizes, for assets or liabilities recorded at fair value, the respective fair value and the classification by level of input within the fair value hierarchy defined above (in thousands):

	March 31, 2013								December 31, 2012
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Assets:
Debt securities:
U.S. treasury securities	$	95,855	$	—	$	—	$	95,855	$	81,903	$	—	$	—	$	81,903
Money market funds	1,633,153		—		—		1,633,153		1,416,355		—		—		1,416,355
U.S. government agencies securities	—		218,038		—		218,038		—		248,952		—		248,952
Municipal debt securities	—		12,115		—		12,115		—		12,088		—		12,088
Corporate debt securities	—		355,063		—		355,063		—		352,718		—		352,718
Residential mortgage and asset-backed securities	—		85,987		—		85,987		—		82,732		—		82,732
Total debt securities	1,729,008		671,203		—		2,400,211		1,498,258		696,490		—		2,194,748
Derivatives	—		43,182		—		43,182		—		14,823		—		14,823
	$	1,729,008	$	714,385	$	—	$	2,443,393	$	1,498,258	$	711,313	$	—	$	2,209,571
Liabilities:
Contingent consideration	$	—	$	—	$	211,084	$	211,084	$	—	$	—	$	205,060	$	205,060
Derivatives	—		18,671		—		18,671		—		65,248		—		65,248
	$	—	$	18,671	$	211,084	$	229,755	$	—	$	65,248	$	205,060	$	270,308

Level 2 Inputs

We estimate the fair values of our government related debt, corporate debt, residential mortgage and asset-backed securities by taking into consideration valuations obtained from third-party pricing services. The pricing services utilize industry standard valuation models, including both income- and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities; issuer credit spreads; benchmark securities; prepayment/default projections based on historical data; and other observable inputs.

Substantially all of our foreign currency derivatives contracts have maturities primarily over an 18 month time horizon and all are with counterparties that have a minimum credit rating of A- or equivalent by Standard & Poor's, Moody's Investors Service, Inc. or Fitch, Inc. We estimate the fair values of these contracts by taking into consideration valuations obtained from a third-party valuation service that utilizes an income-based industry standard valuation model for which all significant inputs are observable, either directly or indirectly. These inputs include foreign currency rates, London Interbank Offered Rates (LIBOR) and swap rates. These inputs, where applicable, are at commonly quoted intervals.

Level 3 Inputs

For the three months ended March 31, 2013, we held no assets measured using Level 3 inputs. For the three months ended March 31, 2012, assets measured at fair value using Level 3 inputs were comprised of auction rate securities and Greek bonds within our available-for-sale investment portfolio. Our policy is to recognize transfers into or out of Level 3 classification as of the actual date of the event or change in circumstances that caused the transfer.

Auction Rate Securities

As of March 31, 2013, we did not hold any auction rate securities. During the third quarter of 2012, we sold our remaining portfolio of auction rate securities and as a result of the sale, we received total proceeds of $37.3 million which resulted in a $3.8 million loss that was recognized in other income (expense), net on our Consolidated Statement of Income.

9

The underlying assets of our auction rate securities consisted of student loans. Although auction rate securities would typically be measured using Level 2 inputs, the failure of auctions and the lack of market activity and liquidity experienced since the beginning of 2008 required that these securities be measured using Level 3 inputs. The fair value of our auction rate securities was determined using a discounted cash flow model that considered projected cash flows for the issuing trusts, underlying collateral and expected yields. Projected cash flows were estimated based on the underlying loan principal, bonds outstanding and payout formulas. The weighted-average life over which the cash flows were projected considered the collateral composition of the securities and related historical and projected prepayments.

Greek Government Bonds

As of March 31, 2013, we did not hold any Greek government bonds. During the first quarter of 2012, the Greek government restructured its sovereign debt which impacted all holders of Greek bonds. As a result, we recorded a $40.1 million loss related to the debt restructuring as part of other income (expense), net on our Consolidated Statement of Income and exchanged the Greek government-issued bonds for new securities, which we liquidated during the first quarter of 2012. We estimated the fair value of the Greek zero-coupon bonds using Level 3 inputs due to the then current lack of market activity and liquidity. The discount rates used in our fair value model for these bonds were based on credit default swap rates.

Contingent Consideration Liabilities

In connection with certain acquisitions, we may be required to pay future consideration that is contingent upon the achievement of specified development, regulatory approval or sales-based milestone events. We estimate the fair value of the contingent consideration liabilities on the acquisition date and each reporting period thereafter using a probability-weighted income approach, which reflects the probability and timing of future payments. This fair value measurement is based on significant Level 3 inputs such as the anticipated timelines and probability of achieving development, regulatory approval or sales-based milestone events and projected revenues. The resulting probability-weighted cash flows are discounted using credit-risk adjusted interest rates.

Each reporting period thereafter, we revalue these obligations by performing a review of the assumptions listed above and record increases or decreases in the fair value of these contingent consideration obligations in research and development (R&D) expenses within our Consolidated Statements of Income until such time that the related product candidate receives marketing approval. In the absence of any significant changes in key assumptions, the quarterly determination of fair values of these contingent consideration obligations would primarily reflect the passage of time.

Significant judgment is employed in determining Level 3 inputs and fair value measurements as of the acquisition date and for each subsequent period. Updates to assumptions could have a significant impact on our results of operations in any given period and actual results may differ from estimates. For example, significant increases in the probability of achieving a milestone or projected revenues would result in a significantly higher fair value measurement while significant decreases in the estimated probability of achieving a milestone or projected revenues would result in a significantly lower fair value measurement. Significant increases in the discount rate or in the anticipated timelines would result in a significantly lower fair value measurement while significant decreases in the discount rate or anticipated timelines would result in a significantly higher fair value measurement.

The potential contingent consideration payments required upon achievement of development or regulatory approval-based milestones related to our CGI Pharmaceuticals, Inc. and Calistoga Pharmaceuticals, Inc. acquisitions range from no payment if none of the milestones are achieved to an estimated maximum of $254.0 million (undiscounted), of which we had accrued $163.9 million as of March 31, 2013 and $159.3 million as of December 31, 2012. The remainder of the contingent consideration liabilities accrual as of March 31, 2013 and December 31, 2012 relates to potential future payments resulting from the acquisition of Arresto Biosciences, Inc. for royalty obligations on future sales once specified sales-based milestones are achieved.

The following table provides a rollforward of our contingent consideration liabilities, which are recorded as part of other long-term obligations in our Consolidated Balance Sheets (in thousands):

Balance at December 31, 2012	$	205,060
Additions from new acquisitions	—
Net changes in valuation	6,024
Balance at March 31, 2013	$	211,084

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3. AVAILABLE-FOR-SALE SECURITIES

The following table is a summary of available-for-sale debt securities recorded in cash and cash equivalents or marketable securities in our Consolidated Balance Sheets (in thousands):

	March 31, 2013									December 31, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Debt securities:
U.S. treasury securities	$	95,661	$	194	$	—		$	95,855	$	81,752	$	151	$	—		$	81,903
Money market funds	1,633,153		—		—			1,633,153		1,416,356		—		—			1,416,356
U.S. government agencies securities	217,680		358		—			218,038		248,595		386		(29		)	248,952
Municipal debt securities	12,049		66		—			12,115		12,062		33		(7		)	12,088
Corporate debt securities	353,468		1,630		(35		)	355,063		351,309		1,492		(84		)	352,717
Residential mortgage and asset-backed securities	86,034		96		(143		)	85,987		82,717		156		(141		)	82,732
Total	$	2,398,045	$	2,344	$	(178	)	$	2,400,211	$	2,192,791	$	2,218	$	(261	)	$	2,194,748

Estimated fair values of available-for-sale securities are generally based on prices obtained from commercial pricing services. The following table summarizes the classification of the available-for-sale debt securities on our Consolidated Balance Sheets (in thousands):

	March 31, 2013		December 31, 2012
Cash and cash equivalents	$	1,633,153	$	1,416,356
Short-term marketable securities	78,804		58,556
Long-term marketable securities	688,254		719,836
Total	$	2,400,211	$	2,194,748

Cash and cash equivalents in the table above exclude cash of $230.8 million and $387.3 million as of March 31, 2013 and December 31, 2012, respectively.

The following table summarizes our portfolio of available-for-sale debt securities by contractual maturity (in thousands):

	March 31, 2013
	Amortized Cost		Fair Value
Less than one year	$	1,711,889	$	1,711,957
Greater than one year but less than five years	661,969		664,058
Greater than five years but less than ten years	9,437		9,460
Greater than ten years	14,750		14,736
Total	$	2,398,045	$	2,400,211

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The following table summarizes the gross realized gains and losses related to sales of marketable securities (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Gross realized gains on sales	$	182		$	10,015
Gross realized losses on sales	$	(156	)	$	(40,096	)

The cost of securities sold was determined based on the specific identification method.

The following table summarizes our available-for-sale debt securities that were in a continuous unrealized loss position, but were not deemed to be other-than-temporarily impaired (in thousands):

	Less Than 12 Months					12 Months or Greater				Total
	Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value
March 31, 2013
Debt securities:
U.S. government agencies securities	$	—		$	—	$	—	$	—	$	—		$	—
Municipal debt securities	—			—		—		—		—			—
Corporate debt securities	(35		)	47,567		—		—		(35		)	47,567
Residential mortgage and asset-backed securities	(143		)	47,748		—		—		(143		)	47,748
Total	$	(178	)	$	95,315	$	—	$	—	$	(178	)	$	95,315
December 31, 2012
Debt securities:
U.S. government agencies securities	$	(29	)	$	26,306	$	—	$	—	$	(29	)	$	26,306
Municipal debt securities	(7		)	3,993		—		—		(7		)	3,993
Corporate debt securities	(84		)	72,722		—		—		(84		)	72,722
Residential mortgage and asset-backed securities	(141		)	36,415		—		—		(141		)	36,415
Total	$	(261	)	$	139,436	$	—	$	—	$	(261	)	$	139,436

As of March 31, 2013 and December 31, 2012, we held a total of 37 and 47 securities, respectively, that were in an unrealized loss position. Based on our review of these securities, we believe we had no other-than-temporary impairments on these securities as of March 31, 2013 and December 31, 2012 because we do not intend to sell these securities and it is not more likely than not that we will be required to sell these securities before the recovery of their amortized cost basis.

4. DERIVATIVE FINANCIAL INSTRUMENTS

We operate in foreign countries, which exposes us to market risk associated with foreign currency exchange rate fluctuations between the U.S. dollar and various foreign currencies, the most significant of which is the Euro. In order to manage this risk, we may hedge a portion of our foreign currency exposures related to outstanding monetary assets and liabilities as well as forecasted product sales using foreign currency exchange forward or option contracts. In general, the market risk related to these contracts is offset by corresponding gains and losses on the hedged transactions. The credit risk associated with these contracts is driven by changes in interest and currency exchange rates and, as a result, varies over time. By working only with major banks and closely monitoring current market conditions, we limit the risk that counterparties to these contracts may be unable to perform. We also limit our risk of loss by entering into contracts that permit net settlement at maturity. Therefore, our overall risk of loss in the event of a counterparty default is limited to the amount of any unrecognized gains on outstanding contracts (i.e., those contracts that have a positive fair value) at the date of default. We do not enter into derivative contracts for trading purposes, nor do we hedge our net investment in any of our foreign subsidiaries.

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We hedge our exposure to foreign currency exchange rate fluctuations for certain monetary assets and liabilities of our foreign subsidiaries that are denominated in a non-functional currency. The derivative instruments we use to hedge this exposure are not designated as hedges, and as a result, changes in their fair value are recorded in other income (expense), net on our Consolidated Statements of Income.

We hedge our exposure to foreign currency exchange rate fluctuations for forecasted product sales that are denominated in a non-functional currency. The derivative instruments we use to hedge this exposure are designated as cash flow hedges and have maturity dates of 18 months or less. Upon executing a hedging contract and quarterly thereafter, we assess prospective hedge effectiveness using a regression analysis which calculates the change in cash flow as a result of the hedge instrument. On a monthly basis, we assess retrospective hedge effectiveness using a dollar offset approach. We exclude time value from our effectiveness testing and recognize changes in the time value of the hedge in other income (expense), net. The effective component of our hedge is recorded as an unrealized gain or loss on the hedging instrument in accumulated OCI within stockholders' equity. When the hedged forecasted transaction occurs, the hedge is de-designated and the unrealized gains or losses are reclassified into product sales. The majority of gains and losses related to the hedged forecasted transactions reported in accumulated OCI at March 31, 2013 will be reclassified to product sales within 12 months. The cash flow effects of our derivatives contracts for the three months ended March 31, 2013 and 2012 are included within net cash provided by operating activities in the Consolidated Statements of Cash Flows.

We had notional amounts on foreign currency exchange contracts outstanding of $3.47 billion and $3.39 billion at March 31, 2013 and December 31, 2012, respectively.

While all of our derivative contracts allow us the right to offset assets or liabilities, we have presented amounts on a gross basis. Under the International Swap Dealers Association, Inc. master agreements with the respective counterparties of the foreign currency exchange contracts, subject to applicable requirements, we are allowed to net settle transactions of the same currency with a single net amount payable by one party to the other. The following table summarizes the location and fair values of derivative instruments on our Consolidated Balance Sheets (in thousands):

	March 31, 2013
	Asset Derivatives			Liability Derivatives
	Classification	Fair Value		Classification	Fair Value
Derivatives designated as hedges:
Foreign currency exchange contracts	Other current assets	$	33,048	Other accrued liabilities	$	17,915
Foreign currency exchange contracts	Other long-term assets	9,697		Other long-term obligations	106
Total derivatives designated as hedges		42,745			18,021
Derivatives not designated as hedges:
Foreign currency exchange contracts	Other current assets	437		Other accrued liabilities	650
Total derivatives not designated as hedges		437			650
Total derivatives		$	43,182		$	18,671

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	December 31, 2012
	Asset Derivatives			Liability Derivatives
	Classification	Fair Value		Classification	Fair Value
Derivatives designated as hedges:
Foreign currency exchange contracts	Other current assets	$	14,556	Other accrued liabilities	$	54,597
Foreign currency exchange contracts	Other long-term assets	142		Other long-term obligations	10,630
Total derivatives designated as hedges		14,698			65,227
Derivatives not designated as hedges:
Foreign currency exchange contracts	Other current assets	125		Other accrued liabilities	21
Total derivatives not designated as hedges		125			21
Total derivatives		$	14,823		$	65,248

The following table summarizes the effect of our foreign currency exchange contracts on our Consolidated Statements of Income (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Derivatives designated as hedges:
Net gains (losses) recognized in OCI (effective portion)	$	70,860		$	(48,886	)
Net gains reclassified from accumulated OCI into product sales (effective portion)	$	462		$	11,227
Losses recognized in other income (expense), net (ineffective portion and amounts excluded from effectiveness testing)	$	(2,132	)	$	(3,212	)
Derivatives not designated as hedges:
Net gains (losses) recognized in other income (expense), net	$	32,620		$	(27,174	)

There were no material amounts recorded in other income (expense), net, for the three months ended March 31, 2013 and 2012 as a result of the discontinuance of cash flow hedges.

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As of March 31, 2013 and December 31, 2012, we held one type of financial instrument, derivative contracts related to foreign currency exchange contracts. The following table summarizes the potential effect of offsetting derivatives by type of financial instrument on our Consolidated Balance Sheets (in thousands):

March 31, 2013
Offsetting of Derivative Assets/Liabilities
									Gross Amounts Not Offset in the Consolidated Balance Sheet
Description	Gross Amounts of Recognized Assets/Liabilities			Gross Amounts Offset in the Consolidated Balance Sheet		Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheet			Derivative Financial Instruments			Cash Collateral Received/Pledged		Net Amount (Legal Offset)
Derivative assets	$	43,182		$	—	$	43,182		$	(18,515	)	$	—	$	24,667
Derivative liabilities	(18,671		)	—		(18,671		)	18,515			—		(156		)

December 31, 2012
Offsetting of Derivative Assets/Liabilities
									Gross Amounts Not Offset in the Consolidated Balance Sheet
Description	Gross Amounts of Recognized Assets/Liabilities			Gross Amounts Offset in the Consolidated Balance Sheet		Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheet			Derivative Financial Instruments			Cash Collateral Received/Pledged		Net Amount (Legal Offset)
Derivative assets	$	14,823		$	—	$	14,823		$	(9,644	)	$	—	$	5,179
Derivative liabilities	(65,248		)	—		(65,248		)	9,644			—		(55,604		)

5. ACQUISITION

YM BioSciences Inc.

We completed the acquisition of YM BioSciences Inc. (YM) for total consideration transferred of $487.6 million on February 8, 2013, at which time YM became a wholly-owned subsidiary of Gilead. YM was a drug development company primarily focused on advancing momelotinib (formally known as CYT387), an orally administered, once-daily candidate for hematologic cancers.

Currently, the purchase accounting is preliminary as management is in the process of reviewing the forecasts that support the valuation. We expect to finalize the purchase accounting during the second quarter of 2013. The preliminary fair values of acquired assets and assumed liabilities include primarily, in-process research and development (IPR&D) of $362.7 million, goodwill of $127.2 million, deferred tax liabilities of $108.8 million and cash acquired of $108.9 million. Pro forma results of operations for the acquisition of YM have not been presented because this acquisition is not material to our consolidated results of operations. See Note 7, Intangible Assets and Goodwill for a description of the IPR&D acquired.

6. INVENTORIES

Inventories are summarized as follows (in thousands):

	March 31, 2013		December 31, 2012
Raw materials	$	693,139	$	826,545
Work in process	529,157		358,525
Finished goods	577,322		559,912
Total	$	1,799,618	$	1,744,982

As of March 31, 2013 and December 31, 2012, the joint ventures formed by Gilead and BMS (See Note 8), which are included in our Consolidated Financial Statements, held $1.27 billion and $1.26 billion in inventory, respectively, of efavirenz active pharmaceutical ingredient which was purchased from BMS at BMS's estimated net selling price of efavirenz.

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7. INTANGIBLE ASSETS AND GOODWILL

Intangible Assets

The following table summarizes the carrying amount of our intangible assets (in thousands):

	March 31, 2013		December 31, 2012
Indefinite-lived intangible assets	$	11,348,900	$	10,986,200
Finite-lived intangible assets	728,648		750,193
Total intangible assets	$	12,077,548	$	11,736,393

Indefinite-Lived Intangible Assets

Our indefinite-lived intangible assets consisted primarily of the purchased IPR&D from our acquisition of Pharmasset, Inc. (Pharmasset) in January 2012. We completed our acquisition of YM in February 2013. Of the total $487.6 million preliminary fair value of acquired assets and assumed liabilities, we attributed approximately $362.7 million to IPR&D related to momelotinib on our Consolidated Balance Sheet. The following table summarizes our indefinite-lived intangible assets (in thousands):

	March 31, 2013		December 31, 2012
Indefinite-lived intangible asset - Sofosbuvir	$	10,720,000	$	10,720,000
Indefinite-lived intangible asset - Momelotinib (formerly CYT387)	362,700		—
Indefinite-lived intangible assets - Other	266,200		266,200
Total	$	11,348,900	$	10,986,200

Finite-Lived Intangible Assets

The following table summarizes our finite-lived intangible assets (in thousands):

	March 31, 2013				December 31, 2012
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Intangible asset - Ranexa	$	688,400	$	147,552	$	688,400	$	133,119
Intangible asset - Lexiscan	262,800		101,902		262,800		95,466
Other	42,995		16,093		42,995		15,417
Total	$	994,195	$	265,547	$	994,195	$	244,002

Amortization expense related to finite-lived intangible assets included in cost of goods sold in our Consolidated Statement of Income totaled $21.5 million and $15.8 million for the three months ended March 31, 2013 and 2012, respectively. The weighted-average amortization period for these intangible assets is approximately 11 years. As of March 31, 2013, the estimated future amortization expense associated with our intangible assets for the remaining nine months of 2013 and each of the five succeeding fiscal years is as follows (in thousands):

Fiscal Year	Amount
2013 (remaining nine months)	$	64,636
2014	92,441
2015	97,673
2016	107,312
2017	116,137
2018	124,561
Total	$	602,760

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Goodwill

Upon completing the acquisition of YM in February 2013, we preliminarily attributed $127.2 million to goodwill on our Consolidated Balance Sheet. The following table summarizes the changes in the carrying amount of goodwill (in thousands):

Balance at December 31, 2012	$	1,060,919
Goodwill resulting from the acquisition of YM	127,238
Balance at March 31, 2013	$	1,188,157

8. COLLABORATIVE ARRANGEMENTS

From time to time, as a result of entering into strategic collaborations, we may hold investments in non-public companies. We review our interests in investee companies for consolidation and/or appropriate disclosure based on applicable guidance. For variable interest entities (VIEs), we may be required to consolidate an entity if the contractual terms of the arrangement essentially provide us with control over the entity, even if we do not have a majority voting interest. We assess whether we are the primary beneficiary of a VIE based on our power to direct the activities of the VIE that most significantly impact the VIE's economic performance and our obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE. As of March 31, 2013, we determined that certain of our investee companies are VIEs; however, other than with respect to our joint ventures with BMS, we are not the primary beneficiary and therefore do not consolidate these investees.

Bristol-Myers Squibb Company

North America

In 2004, we entered into a collaboration arrangement with BMS in the United States to develop and commercialize a single tablet regimen containing our Truvada and BMS's Sustiva (efavirenz). This combination was approved for use in the United States in 2006 and is sold under the brand name Atripla. We and BMS structured this collaboration as a joint venture that operates as a limited liability company named Bristol-Myers Squibb & Gilead Sciences, LLC, which we consolidate. Under the terms of the collaboration we and BMS granted royalty free sublicenses to the joint venture for the use of our respective company owned technologies and, in return, were granted a license by the joint venture to use any intellectual property that results from the collaboration. In 2006, we and BMS amended the joint venture's collaboration agreement to allow the joint venture to sell Atripla into Canada. The economic interests of the joint venture held by us and BMS (including share of revenues and out-of-pocket expenses) is based on the portion of the net selling price of Atripla attributable to efavirenz and Truvada. Since the net selling price for Truvada may change over time relative to the net selling price of efavirenz, both our and BMS's respective economic interests in the joint venture may vary annually.

We and BMS shared marketing and sales efforts. Since the second quarter of 2011, except for a limited number of activities that will be jointly managed, the parties no longer coordinate detailing and promotional activities in the United States, and the parties have begun to reduce their joint promotional efforts since we launched Complera in August 2011 and Stribild in August 2012. The parties will continue to collaborate on activities such as manufacturing, regulatory, compliance and pharmacovigilance. The daily operations of the joint venture are governed by four primary joint committees formed by both BMS and Gilead. We are responsible for accounting, financial reporting, tax reporting, manufacturing and product distribution for the joint venture. Both parties provide their respective bulk active pharmaceutical ingredients to the joint venture at their approximate market values. The agreement will continue until terminated by the mutual agreement of the parties. In addition, either party may terminate the other party's participation in the collaboration within 30 days after the launch of at least one generic version of such other party's single agent products (or the double agent products). The non-terminating party then has the right to continue to sell Atripla, but will be obligated to pay the terminating party certain royalties for a three-year period following the effective date of the termination.

As of March 31, 2013 and December 31, 2012, the joint venture held efavirenz active pharmaceutical ingredient which it purchased from BMS at BMS's estimated net selling price of efavirenz in the U.S. market. These amounts are included in inventories on our Consolidated Balance Sheets. As of March 31, 2013, total assets held by the joint venture were $2.24 billion and consisted primarily of cash and cash equivalents of $147.7 million, accounts receivable of $291.7 million and inventories of $1.74 billion; total liabilities were $1.61 billion and consisted primarily of accounts payable of $569.9 million and other accrued expenses of $367.3 million. As of December 31, 2012, total assets held by the joint venture were $1.95 billion and consisted primarily of cash and cash equivalents of $191.1 million, accounts receivable of $223.7 million and inventories of $1.54 billion; total liabilities were $1.32 billion and consisted primarily of accounts payable of $501.7 million and other accrued expenses of $291.5 million. These asset and liability amounts do not reflect the impact of intercompany eliminations that are included in our Consolidated Balance Sheets. Although we consolidate the joint venture, the legal structure of the joint

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venture limits the recourse that its creditors will have over our general credit or assets. Similarly, the assets held in the joint venture can be used only to settle obligations of the joint venture.

Europe

In 2007, Gilead Sciences Limited, our wholly-owned subsidiary in Ireland, and BMS entered into a collaboration agreement with BMS which sets forth the terms and conditions under which we and BMS will commercialize and distribute Atripla in the European Union, Iceland, Liechtenstein, Norway and Switzerland (collectively, the European Territory). The parties formed a limited liability company which we consolidate, to manufacture Atripla for distribution in the European Territory using efavirenz that it purchases from BMS at BMS's estimated net selling price of efavirenz in the European Territory. We are responsible for manufacturing, product distribution, inventory management and warehousing. Through our local subsidiaries, we have primary responsibility for order fulfillment, collection of receivables, customer relations and handling of sales returns in all the territories where we and BMS promote Atripla. In general, the parties share revenues and out-of-pocket expenses in proportion to the net selling prices of the components of Atripla, Truvada and efavirenz.

Starting in 2012, except for a limited number of activities that will be jointly managed, the parties no longer coordinate detailing and promotional activities in the region. We are responsible for accounting, financial reporting and tax reporting for the collaboration. As of March 31, 2013 and December 31, 2012, efavirenz purchased from BMS at BMS's estimated net selling price of efavirenz in the European Territory is included in inventories on our Consolidated Balance Sheets.

The parties also formed a limited liability company to hold the marketing authorization for Atripla in Europe. We have primary responsibility for regulatory activities. In the major market countries, both parties have agreed to independently continue to use commercially reasonable efforts to promote Atripla.

9. LONG-TERM OBLIGATIONS

Financing Arrangements

The following table summarizes the carrying amount of our borrowings under various financing arrangements (in thousands):

Type of Borrowing	Description	Issue Date	Due Date	Interest Rate	March 31, 2013		December 31, 2012
Convertible Senior	May 2013 Notes	April 2006	May 2013	0.625%	$	342,759	$	419,433
Convertible Senior	May 2014 Notes	July 2010	May 2014	1.00%	1,211,072		1,210,213
Convertible Senior	May 2016 Notes	July 2010	May 2016	1.625%	1,156,632		1,157,692
Senior Unsecured	April 2021 Notes	March 2011	April 2021	4.50%	993,138		992,923
Senior Unsecured	December 2014 Notes	December 2011	December 2014	2.40%	749,473		749,394
Senior Unsecured	December 2016 Notes	December 2011	December 2016	3.05%	699,152		699,095
Senior Unsecured	December 2021 Notes	December 2011	December 2021	4.40%	1,247,501		1,247,428
Senior Unsecured	December 2041 Notes	December 2011	December 2041	5.65%	997,828		997,810
Credit Facility	Five-Year Revolver	January 2012	January 2017	Variable	600,000		750,000
Total debt, net					$	7,997,555	$	8,223,988
Less current portion					942,759		1,169,433
Total long-term debt, net					$	7,054,796	$	7,054,555

Convertible Senior Notes

During the three months ended March 31, 2013, a portion of the Convertible Notes was converted and we repaid $97.1 million of the principal balance. We also paid $100.8 million in cash related to the conversion spread of the notes, which represents the conversion value in excess of the principal amount, and received $100.8 million in cash from our convertible note hedges related to these notes.

Credit Facility

During the first quarter of 2013, we repaid $150.0 million under the Five-Year Revolving Credit Agreement. The Five-Year Revolving Credit Agreement bears interest at either (i) the Eurodollar Rate plus the Applicable Margin or (ii) the Base Rate plus the Applicable Margin, each as defined in the credit agreement. We may reduce the commitments and may prepay the loan in whole or in part at any time without premium or penalty. We are required to comply with certain covenants under the credit agreement and notes indentures and as of March 31, 2013, we were in compliance with all such covenants.

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10. COMMITMENTS AND CONTINGENCIES

Legal Proceedings

Department of Justice Investigation

In June 2011, we received a subpoena from the U.S. Attorney's Office for the Northern District of California requesting documents related to the manufacture, and related quality and distribution practices, of Atripla, Emtriva, Hepsera, Letairis, Truvada, Viread and Complera. We have been cooperating and will continue to cooperate with this governmental inquiry. An estimate of a possible loss or range of losses cannot be determined.

Litigation with Generic Manufacturers

As part of the approval process of some of our products, the U.S. Food and Drug Administration (FDA) granted a New Chemical Entity (NCE) exclusivity period during which other manufacturers' applications for approval of generic versions of our product will not be granted. Generic manufacturers may challenge the patents protecting products that have been granted exclusivity one year prior to the end of the exclusivity period. Generic manufacturers have sought and may continue to seek FDA approval for a similar or identical drug through an abbreviated new drug application (ANDA), the application form typically used by manufacturers seeking approval of a generic drug.

We received notices that generic manufacturers have submitted ANDAs to manufacture a generic version of Atripla, Truvada, Viread, Hepsera, Ranexa and Tamiflu in the United States and Atripla, Truvada and Viread in Canada. We expect to begin trial with some of the generic manufacturers in 2013. In February 2013, Gilead and Teva reached an agreement in principle to settle the ongoing patent litigation concerning the four patents that protect tenofovir disoproxil fumarate in our Viread, Truvada and Atripla products. Under the agreement, Teva will be allowed to launch a generic version of Viread on December 15, 2017. The settlement agreement was recently filed with the Federal Trade Commission (FTC) and Department of Justice (DOJ) and will be final after 45 days if the FTC and DOJ do not object. As a result of the recent invalidation of the patents protecting entecavir and due to declining sales of Hepsera in the United States, in March 2013, we granted Sigmapharm Labs (Sigmapharm) a Covenant Not to Sue if it launches a generic version of Hepsera prior to the expiration of our patents and then filed a motion to dismiss all claims in the lawsuit related to the Hepsera patents. Once Sigmapharm obtains FDA approval of its product, it may launch its generic product. The trial related to ten of the patents associated with Ranexa is scheduled to begin in April 2013. This trial related to three of the patents associated with Truvada in Canada is currently scheduled for hearing in September 2013. The trial related to the two patents protecting emtricitabine patent in our Atripla is scheduled to begin in October 2013.

We cannot predict the ultimate outcome of these actions, and we may spend significant resources enforcing and defending these patents. If we are unsuccessful in these lawsuits, some or all of our original claims in the patents may be narrowed or invalidated and the patent protection for Atripla, Truvada, Viread Ranexa and Tamiflu in the United States and Atripla, Truvada and Viread in Canada could be substantially shortened. Further, if all of the patents covering one or more products are invalidated, the FDA or Canadian Ministry of Health could approve the requests to manufacture a generic version of such products in the United States or Canada, respectively, prior to the expiration date of those patents. The sale of generic versions of these products earlier than their patent expiration would have a significant negative effect on our revenues and results of operations.

Other Matters

We are a party to various legal actions that arose in the ordinary course of our business. We do not believe that any of these legal actions will have a material adverse impact on our consolidated business, financial position or results of operations.

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11. STOCK-BASED COMPENSATION

The following table summarizes the stock-based compensation expense included in our Consolidated Statements of Income (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Cost of goods sold	$	1,841		$	2,101
Research and development expenses	26,875			118,622
Selling, general and administrative expenses	33,051			121,945
Stock-based compensation expense included in total costs and expenses	61,767			242,668
Income tax effect	(16,387		)	(13,064		)
Stock-based compensation expense, net of tax	$	45,380		$	229,604

Total stock-based compensation for the three months ended March 31, 2012 included $100.1 million and $93.8 million in R&D and selling, general and administrative expenses, respectively, related to the acceleration of unvested stock options in connection with the acquisition of Pharmasset, which closed during the first quarter of 2012.

12. STOCKHOLDERS’ EQUITY

Stock Repurchase Program

During the three months ended March 31, 2013, we repurchased a total of $82.2 million or 2.1 million shares of common stock under our January 2011, three-year, $5.00 billion stock repurchase program.

Accumulated Other Comprehensive Income

The following table summarizes the changes in accumulated OCI by component, net of tax (in thousands):

	Foreign Currency Items			Unrealized Gains and Losses on Available-for-Sale Securities			Unrealized Gains and Losses on Cash Flow Hedges			Total
Balance at December 31, 2012	$	30,084		$	(24,002	)	$	(51,697	)	$	(45,615	)
Other comprehensive income (loss) before reclassifications	(8,956		)	1,785			74,060			66,889
Amounts reclassified from accumulated other comprehensive income	—			(17		)	(451		)	(468		)
Net current period other comprehensive income (loss)	(8,956		)	1,768			73,609			66,421
Balance at March 31, 2013	$	21,128		$	(22,234	)	$	21,912		$	20,806

For the three months ended March 31, 2013, amounts reclassified from accumulated OCI were not significant. Amounts reclassified for gains (losses) on cash flow hedges were recorded as part of product sales on our Consolidated Statements of Income. Amounts reclassified for unrealized gains (losses) on available-for-sale securities were recorded as part of other income (expense), net on our Consolidated Statements of Income.

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13. SEGMENT INFORMATION

We operate in one business segment, which primarily focuses on the development and commercialization of human therapeutics for life threatening diseases. All products are included in one segment, because the majority of our products have similar economic and other characteristics, including the nature of the products and production processes, type of customers, distribution methods and regulatory environment.

Product sales consist of the following (in thousands):

	Three Months Ended
	March 31,
	2013		2012
Antiviral products:
Atripla	$	877,073	$	887,596
Truvada	700,242		758,263
Viread	210,332		191,693
Complera/Eviplera	148,189		52,180
Stribild	92,148		—
Hepsera	26,423		29,297
Emtriva	6,671		6,777
Total antiviral products	2,061,078		1,925,806
Letairis	118,107		87,288
Ranexa	96,286		83,201
AmBisome	85,275		84,764
Other products	32,822		27,283
Total product sales	$	2,393,568	$	2,208,342

The following table summarizes revenues from each of our customers who individually accounted for 10% or more of our total revenues (as a percentage of total revenues):

	Three Months Ended
	March 31,
	2013		2012
Cardinal Health, Inc.	19	%	20	%
McKesson Corp.	14	%	16	%
AmerisourceBergen Corp.	11	%	11	%

14. INCOME TAXES

Our income tax rate of 23.7% for the three months ended March 31, 2013 differed from the U.S. federal statutory rate of 35% due primarily to the retroactive extension of the 2012 federal research tax credit in January 2013 and certain operating earnings from non-U.S. subsidiaries that are considered indefinitely reinvested, partially offset by state taxes and our portion of the non-deductible pharmaceutical excise tax. We do not provide for U.S. income taxes on undistributed earnings of our foreign operations that are intended to be permanently reinvested.

In January 2013, the U.S. Congress passed the American Taxpayer Relief Act of 2012 which retroactively reinstated the federal research tax credit for 2012 and 2013. As a result, our income tax provision for the first quarter of 2013 included a discrete tax benefit related to the federal research tax credit for 2012.

We file federal, state and foreign income tax returns in many jurisdictions in the United States and abroad. For federal income tax purposes, the statute of limitations is open for 2008 and onwards. For certain acquired entities, the statute of limitations is open for all years from inception due to our utilization of their net operating losses and credits carried over from prior years. For California income tax purposes, the statute of limitations is open for 2008 and onwards.

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Our income tax returns are audited by federal, state and foreign tax authorities. We are currently under examination by the Internal Revenue Service (IRS) for the 2008 and 2009 tax years and by various state and foreign jurisdictions. There are differing interpretations of tax laws and regulations, and as a result, significant disputes may arise with these tax authorities involving issues of the timing and amount of deductions and allocations of income among various tax jurisdictions. We periodically evaluate our exposures associated with our tax filing positions.

As of March 31, 2013, we believe that it is reasonably possible that our unrecognized tax benefits will decrease by approximately$18 million in the next 12 months as we expect to have clarification from the IRS and other tax authorities regarding some of our uncertain tax positions. With respect to the remaining unrecognized tax benefits, we are currently unable to make a reasonable estimate as to the period of cash settlement, if any, with the respective tax authorities.

We record liabilities related to uncertain tax positions in accordance with the income tax guidance which clarifies the accounting for uncertainty in income taxes recognized in an enterprise’s financial statements by prescribing a minimum recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. We do not believe any of our uncertain tax positions will have a material adverse effect on our Consolidated Financial Statements, although an adverse resolution of one or more of these uncertain tax positions in any period could have a material impact on the results of operations for that period.

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

This Quarterly Report on Form 10-Q contains forward-looking statements regarding future events and our future results that are subject to the safe harbors created under the Securities Act of 1933, as amended (the Securities Act), and the Securities Exchange Act of 1934, as amended (the Exchange Act). The forward-looking statements are contained principally in this section entitled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Risk Factors.” Words such as “expect,” “anticipate,” “target,” “goal,” “project,” “hope,” “intend,” “plan,” “believe,” “seek,” “estimate,” “continue,” “may,” “could,” “should,” “might,” variations of such words and similar expressions are intended to identify such forward-looking statements. In addition, any statements other than statements of historical fact are forward-looking statements, including statements regarding overall trends, operating cost and revenue trends, liquidity and capital needs and other statements of expectations, beliefs, future plans and strategies, anticipated events or trends and similar expressions. We have based these forward-looking statements on our current expectations about future events. These statements are not guarantees of future performance and involve risks, uncertainties and assumptions that are difficult to predict. Our actual results may differ materially from those suggested by these forward-looking statements for various reasons, including those identified below under “Risk Factors.” Given these risks and uncertainties, you are cautioned not to place undue reliance on forward-looking statements. The forward-looking statements included in this report are made only as of the date hereof. Except as required under federal securities laws and the rules and regulations of the Securities and Exchange Commission (SEC), we do not undertake, and specifically decline, any obligation to update any of these statements or to publicly announce the results of any revisions to any forward-looking statements after the distribution of this report, whether as a result of new information, future events, changes in assumptions or otherwise. In evaluating our business, you should carefully consider the risks described in the section entitled “Risk Factors” under Part II, Item 1A below, in addition to the other information in this Quarterly Report on Form 10-Q. Any of the risks contained herein could materially and adversely affect our business, results of operations and financial condition.

You should read the following management’s discussion and analysis of our financial condition and results of operations in conjunction with our audited Consolidated Financial Statements and related notes thereto included as part of our Annual Report on Form 10-K for the year ended December 31, 2012 and our unaudited Consolidated Financial Statements for the three months ended March 31, 2013 and other disclosures (including the disclosures under “Part II. Item 1A. Risk Factors”) included in this Quarterly Report on Form 10-Q. Our Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and are presented in U.S. dollars.

Management Overview

Gilead Sciences, Inc. (Gilead, we or us), incorporated in Delaware on June 22, 1987, is a research-based biopharmaceutical company that discovers, develops and commercializes innovative medicines in areas of unmet medical need. With each new discovery and experimental drug candidate, we seek to improve the care of patients suffering from life-threatening diseases around the world. Gilead's primary areas of focus include human immunodeficiency virus (HIV), liver diseases such as hepatitis B virus (HBV) and hepatitis C virus (HCV), serious cardiovascular and respiratory conditions and oncology/inflammation. Headquartered in Foster City, California, we have operations in North America, Europe and Asia-Pacific. We continue to add to our existing portfolio of products through our internal discovery and clinical development programs and through our product acquisition and in-licensing strategy.

Our product portfolio is comprised of Stribild^®, Complera^®/Eviplera^®, Atripla^®, Truvada^®, Viread^®, Hepsera^®, Emtriva^®, Letairis^®, Ranexa^®, AmBisome^®, Cayston^® and Vistide^®. We have U.S. and international commercial sales operations, with marketing subsidiaries in North America, Europe and Asia-Pacific. In addition, we also sell and distribute certain products through our corporate partners under royalty-paying collaborative agreements.

Business Highlights

During the first quarter of 2013, our product sales increased8% over the same quarter in 2012, and we continued to advance our product pipeline across all therapeutic areas. We believe the combination of our existing internal research programs and our recent acquisitions and partnerships will allow us to continue to bring innovative therapies to individuals who are living with unmet medical needs. During the quarter, we made the following announcements:

HIV Program

• Initiated two Phase 3 clinical trials evaluating a single tablet regimen containing tenofovir alafenamide (TAF) for the treatment of HIV-1 infection in treatment-naïve adults;

• Announced Phase 2 study results evaluating a once-daily single tablet regimen containing TAF was similar to a regimen of Stribild;

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• Reached an agreement with Teva Pharmaceuticals (Teva) to settle ongoing patent litigation under which Teva will be allowed to launch a generic version of Viread on December 15, 2017; and

• The scientific committee of the European Medicines Agency adopted a positive opinion on our marketing authorisation application for Stribild.

In April, the U.S. Food and Drug Administration (FDA) issued complete response letters on our new drug applications (NDAs) for elvitegravir and cobicistat for us as part of HIV treatment regimens. The letters noted that the FDA cannot approve the applications in their current form due to deficiencies in documentation and validation of certain observations noted during a recent inspection. We are taking all necessary steps to address the agency's questions and move the applications forward. The FDA did not raise any concerns with the safety profiles of elvitegravir and cobicistat. This regulatory action does not affect the marketing authorization or continued use of Stribild.

HCV Program

• Announced full clinical trial results of the Phase 2 ELECTRON study that confirmed all patients achieved a sustained virologic response (SVR) four weeks after stopping therapy;

• Initiated and provided an update on the Phase 3 ION-1 study evaluating a once-daily fixed-dose combination of sofosbuvir/ledipasvir with and without ribavirin (RBV) for 12 or 24 weeks in treatment naïve genotype 1 HCV patients. A planned review by the study's Data and Safety Monitoring Board of safety data concluded that the trial should continue without modification;

• Began screening and completed enrollment in the second Phase 3 ION-2 study evaluating sofosbuvir/ledipasvir with RBV for 12 weeks, and with and without RBV for 24 weeks, in treatment-experienced genotype 1 HCV patients;

• Enrolled patients in the Phase 2 LONESTAR study of sofosbuvir/ledipasvir with and without RBV for eight weeks and of sofosbuvir/ledipasvir for 12 weeks in genotype 1 treatment-naïve patients;

• Announced topline results from the Phase 3 FISSION study, evaluating therapy with either a 12-week course of sofosbuvir plus RBV or standard of care with 24 weeks of treatment with pegylated interferon (peg-IFN) plus RBV in genotype 2 or 3 HCV patients which met its primary efficacy endpoint of non-inferiority; and

• Announced topline results from the Phase 3 NEUTRINO and FUSION studies, evaluating 12- and 16-week courses of various therapies with sofosbuvir, RBV and peg-IFN in genotypes 1, 2, 3, 4, 5 and 6 HCV patients. The studies met their primary efficacy endpoints of superiority compared to a predefined historic control SVR rate.

In April, we filed a new drug application with the FDA for approval of sofosbuvir, a once-daily oral nucleotide analogue for the treatment of chronic HCV infection. The data submitted, primarily from four phase 3 studies, NEUTRINO, FISSION, POSITRON and FUSION, support the use of sofosbuvir and RBV as an all-oral therapy for patients with genotype 2 and 3 HCV infection and sofosbuvir in combination with RBV and peg-IFN for treatment-naïve patients with genotype 1, 4, 5 and 6 infection.

Cardiovascular Program

In March, we announced data from the Phase 4 TERISA (Type 2 Diabetes Evaluation of Ranolazine In Subjects With Chronic Stable Angina) study, which demonstrated that the addition of ranolazine to background antianginal therapy in chronic angina patients with type 2 diabetes significantly reduced the frequency of weekly angina episodes compared to background antianginal therapy alone.

Acquisition

We completed the acquisition of YM BioSciences Inc. (YM) for $487.6 million in cash on February 8, 2013, at which time YM became a wholly-owned subsidiary of Gilead. YM was a drug development company primarily focused on advancing momelotinib (formally known as CYT387), an orally administered, once-daily candidate for hematologic cancers. The acquisition of YM represents an opportunity to add a complementary clinical program in the area of hematologic cancers to our oncology portfolio.

Currently, the purchase accounting is preliminary as management is in the process of reviewing the forecasts that support the valuation. We expect to finalize the purchase accounting during the second quarter of 2013. The preliminary purchase accounting attributed $362.7 million to in-process research and development, $127.2 million to goodwill, $108.8 million to deferred tax liabilities and $108.9 million to cash acquired.

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Financial Highlights

During the first quarter of 2013, total revenues increased11% to $2.53 billion, compared to $2.28 billion in the first quarter of 2012, driven by strong underlying demand for our products and an increase in royalty revenues. Total product sales were $2.39 billion for the first quarter of 2013, an increase of 8% compared to the same period in 2012, due primarily to growth in our antiviral franchise, which increased7% to $2.06 billion. Cardiovascular product sales, which include Letairis and Ranexa, totaled $214.4 million, an increase of 26% compared to the same period in 2012. Royalty revenues from our collaborations with corporate partners were $134.4 million, an increase of 89% compared to the prior year, due primarily to higher Tamiflu royalty revenues from Roche.

Research and development (R&D) expenses increased9% to $497.6 million for the first quarter of 2013 compared to the same period in 2012 as we continued to progress and invest in the expansion of our product pipeline, particularly in liver disease and oncology. Selling, general and administrative (SG&A) expenses were $374.3 million for the first quarter of 2013, a decrease of $68.8 million or 16% compared to the first quarter of 2012. The decrease in operating expenses was primarily due to stock-based compensation expense of $198.1 million related to our acquisition of Pharmasset, Inc. (Pharmasset) in January 2012.

Net income attributable to Gilead for the first quarter of 2013 was $722.2 million or $0.43 per diluted share, a 63%increase compared to the same period in 2012, primarily due to an increase in total revenues driven by strong underlying demand for our products and a decrease in SG&A expenses, partially offset by an increase in R&D expenses. Additionally, our effective tax rate for the first quarter of 2013 decreased primarily due to the passage of the American Taxpayer Relief Act of 2012 in January 2013 which retroactively reinstated the federal research tax credit for 2012.

As of March 31, 2013, cash, cash equivalents and marketable securities totaled $2.63 billion, an increase of $48.9 million compared to December 31, 2012. During the first quarter of 2013, we generated $672.1 million of operating cash flows, utilized $378.6 million for the acquisition of YM and repaid $247.1 million in debt, net of proceeds from convertible note hedges.

Results of Operations

Total Revenues

Total revenues include product sales, royalty revenues, and contract and other revenues. Total revenues for three months ended March 31, 2013 were $2.53 billion, up11% compared to $2.28 billion for the same period in 2012. The increase in total revenues was driven by strong underlying demand for our products and higher royalty revenues from our collaborations with corporate partners.

Product Sales

Total product sales were $2.39 billion for the three months ended March 31, 2013, an increase of 8% compared to total product sales of $2.21 billion for the same period in 2012, driven primarily by an increase in antiviral and cardiovascular product sales. Sequentially, total product sales decreased5% due primarily to declines in wholesaler and sub-wholesaler inventories of Truvada and Atripla in the United States.

Product sales in the United States increased by 10% for the three months ended March 31, 2013 compared to the same period in 2012, primarily driven by higher underlying demand for our antiviral products, specifically Complera and Stribild and our cardiovascular products, Letairis and Ranexa. Sequentially, total product sales in the United States decreased7% due primarily to lower wholesaler and sub-wholesaler inventory levels. We believe the decrease was due in part to inventory-build in the prior quarter and measured purchases by the VA in the current quarter. As inventory held by our customers fluctuates from quarter to quarter, we may continue to see fluctuations in our quarterly product sales in the future.

More than 40% of our product sales are generated outside of the United States and as a result, we face exposure to adverse movements in foreign currency exchange rates, primarily in Euro. We used foreign currency exchange forward contracts to hedge a percentage of our foreign currency exposure. Foreign currency exchange, net of hedges, had an unfavorable impact of $7.3 million on our first quarter2013 product sales compared to the same period in 2012.

Product sales in Europe increased by 7% for the three months ended March 31, 2013 to $818.3 million compared to $763.9 million for the same period in 2012, primarily driven by strong underlying demand for our antiviral products and increased sales of cardiovascular products, including Letairis and Ranexa. Antiviral product sales in Europe totaled $750.4 million for the three months ended March 31, 2013, an increase of 8% compared to $696.5 million for the same period in 2012, primarily driven by the sales of Eviplera, Truvada and Atripla. Foreign currency exchange, net of hedges, had an unfavorable impact of $7.0 million on our European product sales for the three months ended March 31, 2013 compared to the same period in 2012.

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Recently, many countries in the European Union have increased the amount of discounts required on our products and these efforts could continue as countries attempt to manage healthcare expenditures, especially in light of the severe fiscal and debt crises experienced by many countries in the European Union. For example, France implemented a mandatory price decrease on HIV drugs effective April 2013.

The following table summarizes the period over period changes in our product sales (in thousands):

	Three Months Ended
	March 31,
	2013		2012		Change
Antiviral products:
Atripla	$	877,073	$	887,596	(1	)%
Truvada	700,242		758,263		(8	)%
Viread	210,332		191,693		10	%
Complera/Eviplera	148,189		52,180		184	%
Stribild	92,148		—		—
Hepsera	26,423		29,297		(10	)%
Emtriva	6,671		6,777		(2	)%
Total antiviral products	2,061,078		1,925,806		7	%
Letairis	118,107		87,288		35	%
Ranexa	96,286		83,201		16	%
AmBisome	85,275		84,764		1	%
Other	32,822		27,283		20	%
Total product sales	$	2,393,568	$	2,208,342	8	%

Antiviral Products

Antiviral product sales increased by 7% for the three months ended March 31, 2013 compared to the same period in 2012.

• Atripla

Atripla sales decreased by 1% for the three months ended March 31, 2013 compared to the same period in 2012, due primarily to the timing of purchases in Latin America. Atripla sales accounted for 43% and 46% of our total antiviral product sales for the three months ended March 31, 2013 and 2012, respectively. The efavirenz component of Atripla, which has a gross margin of zero, comprised $328.1 million and $326.4 million of our Atripla sales for the three months ended March 31, 2013 and 2012, respectively.

• Truvada

Truvada sales decreased by 8% for the three months ended March 31, 2013 compared to the same period in 2012, due primarily to declines in wholesaler and sub-wholesaler inventories in the United States. Truvada sales accounted for 34% and 39% of our total antiviral product sales for the three months ended March 31, 2013 and 2012, respectively.

• Complera/Eviplera

Complera/Eviplera sales increased by 184% for the three months ended March 31, 2013 compared to the same period in 2012, primarily due to sales volume growth in Europe and the United States.

• Stribild

Sales of Stribild were $92.1 million for the three months ended March 31, 2013. Stribild was approved in the United States in August 2012.

Cardiovascular Products

Cardiovascular product sales increased 26% during the first quarter of 2013 compared to the same period in 2012. During the three months ended March 31, 2013, sales of Letairis increased by 35% and sales of Ranexa increased by 16% compared to the same period in 2012, primarily due to increases in underlying demand.

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Royalty Revenues

The following table summarizes the period over period changes in our royalty revenues (in thousands):

	Three Months Ended
	March 31,
	2013		2012		Change
Royalty revenues	$	134,407	$	71,105	89	%

Royalty revenues increased89% for the three months ended March 31, 2013 compared to the same period in 2012, driven primarily by higher Tamiflu royalty revenues from Roche. We recognize royalties on Tamiflu sales by Roche in the quarter following the quarter in which the corresponding sales occur.

Cost of Goods Sold and Product Gross Margin

The following table summarizes the period over period changes in our product sales (in thousands), cost of goods sold (in thousands) and product gross margin:

	Three Months Ended
	March 31,
	2013			2012			Change
Total product sales	$	2,393,568		$	2,208,342		8	%
Cost of goods sold	$	634,448		$	580,931		9	%
Product gross margin	73		%	74		%

Our product gross margin for the three months ended March 31, 2013 was 73%, a decrease of 1% compared to the same period in 2012, due primarily to changes in our product mix.

Research and Development Expenses

	Three Months Ended
	March 31,
(In thousands, except percentages)	2013		2012		Change
Research and development	$	497,632	$	458,211	9	%

We manage our R&D expenses by identifying the R&D activities we anticipate will be performed during a given period and then prioritizing efforts based on scientific data, probability of successful development, market potential, available human and capital resources and other considerations. We continually review our R&D pipeline and the status of development and, as necessary, reallocate resources among the R&D portfolio that we believe will best support the future growth of our business.

R&D expenses summarized above consist primarily of clinical studies performed by contract research organizations (CROs), materials and supplies, licenses and fees, milestone payments under collaboration arrangements, personnel costs, including salaries, benefits and stock-based compensation and overhead allocations consisting of various support and facilities-related costs.

R&D expenses for the three months ended March 31, 2013increased by $39.4 million or 9% compared to the same period in 2012, due primarily to a $93.9 million increase in clinical studies and outside services expenses. This change was partially offset by a $64.7 million decrease in personnel expenses which included $100.1 million in stock-based compensation expense related to our acquisition of Pharmasset in January 2012.

Selling, General and Administrative Expenses

	Three Months Ended
	March 31,
(In thousands, except percentages)	2013		2012		Change
Selling, general and administrative	$	374,296	$	443,121	(16	)%

SG&A expenses relate to sales and marketing, finance, human resources, legal and other administrative activities. Expenses are primarily comprised of facilities and overhead costs, outside marketing, advertising and legal expenses and other general and administrative costs.

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SG&A expenses for the three months ended March 31, 2013decreased by $68.8 million or 16%, compared to the same period in 2012, due primarily to an $88.8 million decrease in stock-based compensation expense which included $98.0 million resulting from our acquisition of Pharmasset in January 2012. This change was partially offset by increased headcount related and other expenses to support the ongoing growth of our business. As we prepare for the launch of sofosbuvir, we expect headcount and other expenses to continue to increase throughout the remainder of the year.

Interest Expense

Interest expense for the three months ended March 31, 2013 was $81.8 million and decreased by $15.5 million compared to the same period in 2012. The decrease was primarily due to bridge financing costs associated with our acquisition of Pharmasset in January 2012 which did not reoccur in the current period and the repayment of bank debt totaling $1.40 billion in 2012.

Other Income (Expense), Net

Other income (expense), net for the three months ended March 31, 2013 was a net expense of $(3.3) million compared to a net expense of $(34.1) million for the three months ended March 31, 2012, due primarily to a $40.1 million loss on Greek bonds related to Greece's restructuring of its sovereign debt in the same period in 2012.

Provision for Income Taxes

Our provision for income taxes was $222.4 million and $231.3 million for the three months ended March 31, 2013 and 2012, respectively. Our effective tax rate was 23.7% and 34.6% for the three months ended March 31, 2013 and 2012, respectively. The effective tax rate for the three months ended March 31, 2013 was lower than the effective tax rate for the same period in 2012 as a result of the retroactive extension of the 2012 federal research tax credit in January 2013 and the first quarter of 2012 stock-based compensation expense related to the Pharmasset acquisition for which we receive no tax benefit.

The effective tax rate for the three months ended March 31, 2013 differed from the U.S. federal statutory rate of 35% due primarily to the retroactive extension of the 2012 federal research tax credit in January 2013 and certain operating earnings from non-U.S. subsidiaries that are considered indefinitely reinvested, partially offset by state taxes and our portion of the non-deductible pharmaceutical excise tax. We do not provide for U.S. income taxes on undistributed earnings of our foreign operations that are intended to be indefinitely reinvested in our foreign subsidiaries.

In January 2013, the U.S. Congress passed the American Taxpayer Relief Act of 2012 which retroactively reinstated the federal research tax credit for 2012 and 2013. As a result, our income tax provision for the first quarter of 2013 included a discrete tax benefit related to the federal research tax credit for 2012.

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Liquidity and Capital Resources

We believe that our existing capital resources, supplemented by our cash flows generated from operating activities will be adequate to satisfy our capital needs for the foreseeable future. The following table summarizes our cash, cash equivalents and marketable securities, our working capital and our cash flow activities as of the end of, and for each of, the periods presented (in thousands):

	March 31, 2013		December 31, 2012
Cash, cash equivalents and marketable securities	$	2,631,030	$	2,582,086
Working capital	$	2,372,882	$	1,886,327

	Three Months Ended
	March 31,
	2013			2012
Cash provided by (used in):
Operating activities	$	672,101		$	452,969
Investing activities	$	(407,256	)	$	(10,743,116	)
Financing activities	$	(199,001	)	$	1,855,590

Cash, Cash Equivalents and Marketable Securities

As of March 31, 2013, cash, cash equivalents and marketable securities totaled $2.63 billion, an increase of $48.9 million or 2% from December 31, 2012. During the first quarter of 2013, we generated $672.1 million in cash flows from operations, utilized $378.6 million for the acquisition of YM and repaid $247.1 million in debt, net of proceeds from convertible note hedges.

Of the total cash, cash equivalents and marketable securities at March 31, 2013, approximately $1.25 billion was generated from operations in foreign jurisdictions and is intended for use in our foreign operations. We do not rely on unrepatriated earnings as a source of funds for our domestic business as we expect to have sufficient cash flow and borrowing capacity in the United States to fund our domestic operational and strategic needs.

Working Capital

Working capital was $2.37 billion at March 31, 2013. The increase of $486.6 million in working capital from December 31, 2012 was primarily due to a decrease in the current portion of long-term debt and other obligations, net related to the repayment of our bank debt and conversions of our convertible senior notes due in May 2013 and an increase in accounts receivable, net, primarily driven by the timing of sales during the quarter.

Cash Provided by Operating Activities

Cash provided by operating activities of $672.1 million for the three months ended March 31, 2013 primarily related to net income of $717.7 million, adjusted for non-cash items such as $74.3 million of depreciation and amortization expenses and $61.8 million of stock-based compensation expenses. This was partially offset by $227.4 million of net cash outflow related to changes in operating assets and liabilities.

Cash provided by operating activities of $453.0 million for the three months ended March 31, 2012 primarily related to net income of $437.5 million, adjusted for non-cash items such as $66.2 million of depreciation and amortization expenses, $48.7 million of stock-based compensation expenses and $51.4 million of deferred income taxes. This was partially offset by $159.5 million of net cash outflow related to changes in operating assets and liabilities.

Cash Used in Investing Activities

Cash used in investing activities for the three months ended March 31, 2013 was $407.3 million, consisting primarily of $378.6 million used in our acquisition of YM, net of the cash acquired.

Cash used in investing activities for the three months ended March 31, 2012 was $10.74 billion, consisting primarily of $10.75 billion used in our acquisition of Pharmasset, net of stock-based compensation expense and cash acquired.

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Cash Provided by (Used in) Financing Activities

Cash used in financing activities for the three months ended March 31, 2013 was $199.0 million, driven primarily by $247.1 million used to repay debt financing, net of $100.8 million in proceeds received related to our convertible note hedges, and $82.2 million used to repurchase common stock under our stock repurchase program, including commissions. The cash outflows were partially offset by $86.0 million in proceeds from issuances of common stock under our employee stock plans.

Cash provided by financing activities for the three months ended March 31, 2012 was $1.86 billion, driven primarily by net proceeds of $2.14 billion from the issuance of bank debt in conjunction with the Pharmasset acquisition and $132.5 million in proceeds from issuances of common stock under our employee stock plans. The cash proceeds were partially offset by the $350.0 million used to repay bank debt during the quarter.

Long-Term Obligations

The following is a summary of our borrowings under various financing arrangements (in thousands):

Type of Borrowing	Description	Issue Date	Due Date	Interest Rate	March 31, 2013		December 31, 2012
Convertible Senior	May 2013 Notes	April 2006	May 2013	0.625%	$	342,759	$	419,433
Convertible Senior	May 2014 Notes	July 2010	May 2014	1.00%	1,211,072		1,210,213
Convertible Senior	May 2016 Notes	July 2010	May 2016	1.625%	1,156,632		1,157,692
Senior Unsecured	April 2021 Notes	March 2011	April 2021	4.50%	993,138		992,923
Senior Unsecured	December 2014 Notes	December 2011	December 2014	2.40%	749,473		749,394
Senior Unsecured	December 2016 Notes	December 2011	December 2016	3.05%	699,152		699,095
Senior Unsecured	December 2021 Notes	December 2011	December 2021	4.40%	1,247,501		1,247,428
Senior Unsecured	December 2041 Notes	December 2011	December 2041	5.65%	997,828		997,810
Credit Facility	Five-Year Revolver	January 2012	January 2017	Variable	600,000		750,000
Total debt, net					$	7,997,555	$	8,223,988
Less current portion					942,759		1,169,433
Total long-term debt, net					$	7,054,796	$	7,054,555

In January 2012, in conjunction with our acquisition of Pharmasset, we entered into a five-year $1.25 billion revolving credit facility credit agreement (the Five-Year Revolving Credit Agreement), a $750.0 million short-term revolving credit facility credit agreement (the Short-Term Revolving Credit Agreement) and a $1.00 billion term loan facility (the Term Loan Credit Agreement). We borrowed $750.0 million under the Five-Year Revolving Credit Agreement, $400.0 million under the Short-Term Revolving Credit Agreement and $1.00 billion under the Term Loan Credit Agreement, upon the close of the acquisition.

In 2012, we fully repaid the outstanding debt under the Term Loan Credit Agreement and the Short-Term Revolving Credit Agreement, at which time both agreements terminated. During the first quarter of 2013, we repaid $150.0 million under the Five-Year Revolving Credit Agreement and $97.1 million of the principal balance related to conversions of our convertible senior notes.

The Five-Year Revolving Credit Agreement contains customary representations, warranties, affirmative, negative and financial maintenance covenants and events of default. The loan bears interest at either (i) the Eurodollar Rate plus the Applicable Margin or (ii) the Base Rate plus the Applicable Margin, each as defined in the credit agreement. We may reduce the commitments and may prepay the loan in whole or in part at any time without premium or penalty. We are required to comply with certain covenants under the credit agreement and notes indentures and as of March 31, 2013, we were in compliance with all such covenants.

Convertible Senior Notes

On May 1, 2013, our May 2013 Notes matured. During the second quarter of 2013, we will repay an aggregate principal balance of approximately $345.0 million related to the conversions and maturity of our May 2013 Notes. Additionally, subsequent to March 31, 2013 and through the filing of this form, we have been notified of conversions related to our May 2014 Notes estimated at approximately $257.0 million in aggregate principal. As our stock price exceeds the conversion prices of our Convertible Notes, we may continue to see conversions of our May 2014 Notes and May 2016 Notes.

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Critical Accounting Policies, Estimates and Judgments

There have been no material changes in our critical accounting policies, estimates and judgments during the three months ended March 31, 2013 compared to the disclosures in Part II, Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2012.

Off Balance Sheet Arrangements

We do not have any off balance sheet arrangements as defined in Item 303(a)(4)(ii) of Regulation S-K.

Recent Accounting Pronouncements

In January 2013, the Financial Accounting Standards Board (FASB) issued an update to clarify the scope of disclosures for offsetting assets and liabilities. The update was effective for us beginning in the first quarter of 2013 and was applied retrospectively for all comparative periods presented. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

In February 2013, the FASB issued a new standard to improve the reporting of reclassification adjustments out of accumulated other comprehensive income (OCI). The update requires disclosure of amounts reclassified out of accumulated OCI by component. In addition, if the amount reclassified is required to be reclassified to net income in its entirety in the same reporting period, an entity is required to present significant amounts reclassified out of accumulated OCI by the respective line items of net income. The updated standard was effective for us beginning in the first quarter of 2013. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

In February 2013, the FASB also issued an update to the existing standard for liabilities. The update provides guidance for the recognition, measurement and disclosure of obligations resulting from joint and several liability arrangements. For obligations for which the total amount is fixed at the reporting date, an entity will be required to measure those obligations as the sum of the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. Such entities will also be required to disclose the nature, amount and other significant information about the obligations. This guidance will become effective for us beginning in the first quarter of 2014. We are evaluating the financial statement impact of this guidance. Currently, we do not expect that adopting this update will have a material impact on our Consolidated Financial Statements.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

There have been no material changes in our market risk during the three months ended March 31, 2013 compared to the disclosures in Part II, Item 7A of our Annual Report on Form 10-K for the year ended December 31, 2012.

As of March 31, 2013, our accounts receivable in Southern Europe, specifically Greece, Italy, Portugal and Spain, totaled approximately $849.6 million, of which $348.5 million were greater than 120 days past due and $114.1 million were greater than 365 days past due. To date, we have not experienced significant losses with respect to the collection of our accounts receivable. We believe that our allowance for doubtful accounts was adequate at March 31, 2013.

Within Greece, the number of days our receivables are outstanding has continued to increase. To date, we have not experienced significant losses with respect to the collection of our accounts receivable. However, we will continue to monitor the European economic environment for any collectability issues related to our outstanding receivables.

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ITEM 4. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

An evaluation as of March 31, 2013 was carried out under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, of the effectiveness of our “disclosure controls and procedures,” which are defined in Rule 13a-15(e) under the Securities Exchange Act of 1934, as amended (the Exchange Act), as controls and other procedures of a company that are designed to ensure that the information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the Securities and Exchange Commission's rules and forms, and that such information is accumulated and communicated to the company’s management, including its Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure. Based upon that evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective at March 31, 2013.

Changes in Internal Control over Financial Reporting

Our management, including our Chief Executive Officer and Chief Financial Officer, has evaluated any changes in our internal control over financial reporting that occurred during the quarter ended March 31, 2013, and has concluded that there was no change during such quarter that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Limitations on the Effectiveness of Controls

A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Because of inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues, if any, within a company have been detected. Accordingly, our disclosure controls and procedures are designed to provide reasonable, not absolute, assurance that the objectives of our disclosure control system are met and, as set forth above, our Chief Executive Officer and Chief Financial Officer have concluded, based on their evaluation as of the end of the period covered by this report, that our disclosure controls and procedures were effective to provide reasonable assurance that the objectives of our disclosure control system were met.

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PART II. OTHER INFORMATION

ITEM  1. LEGAL PROCEEDINGS

Litigation with Generic Manufacturers

Tenofovir Disoproxil Fumarate, Emtricitabine and Fixed-dose Combination of Emtricitabine, Tenofovir Disoproxil Fumarate and Efavirenz

In November 2008, we received notice that Teva Pharmaceuticals (Teva) submitted an abbreviated new drug application (ANDA) to the U.S. Food and Drug Administration (FDA) requesting permission to manufacture and market a generic version of Truvada. In the notice, Teva alleges that two of the patents associated with emtricitabine, owned by Emory University and licensed exclusively to us, are invalid, unenforceable and/or will not be infringed by Teva's manufacture, use or sale of a generic fixed-dose combination of emtricitabine and tenofovir disoproxil fumarate. In December 2008, we filed a lawsuit in U.S. District Court in New York against Teva for infringement of the two emtricitabine patents. In March 2009, we received notice that Teva submitted an ANDA to the FDA requesting permission to manufacture and market a generic fixed-dose combination of emtricitabine, tenofovir disoproxil fumarate and efavirenz. In the notice, Teva challenged the same two emtricitabine patents. In May 2009, we filed another lawsuit in U.S. District Court in New York against Teva for infringement of the two emtricitabine patents, and this lawsuit was consolidated with the lawsuit filed in December 2008. In January 2010, we received notice that Teva submitted an ANDA to the FDA requesting permission to manufacture and market a generic version of Viread. In the notice, Teva challenged four of the tenofovir disoproxil fumarate patents protecting Viread. In January 2010, we also received notices from Teva amending its ANDAs related to generic versions of our Atripla and Truvada products. In the notice related to Teva's ANDA for a generic version of Atripla, Teva challenged four patents related to tenofovir disoproxil fumarate, two additional patents related to emtricitabine and two patents related to efavirenz. In the notice related to Teva's ANDA for a generic version of Truvada, Teva challenged four patents related to tenofovir disoproxil fumarate and two additional patents related to emtricitabine. In March 2010, we filed lawsuits against Teva for infringement of the four Viread patents and two additional emtricitabine patents. In March 2010, Bristol-Myers Squibb Company and Merck & Co., Inc. filed a lawsuit against Teva for infringement of the patents related to efavirenz. Because we filed our lawsuits within the requisite 45 day period provided in the Hatch Waxman Act, there were stays preventing FDA approval of Teva's ANDAs for 30 months or until a district court decision adverse to the patents. The 30-month stay for all three Teva ANDAs expired in July 2012. In February 2013, Gilead and Teva reached an agreement in principle to settle the ongoing patent litigation concerning the four patents that protect tenofovir disoproxil fumarate in our Viread, Truvada and Atripla products. Under the agreement, Teva will be allowed to launch a generic version of Viread on December 15, 2017. The settlement agreement was recently filed with the Federal Trade Commission (FTC) and Department of Justice (DOJ) for their review and will be final after 45 days if the FTC and DOJ do not object.

In November 2011, we received notice that Teva submitted an Abbreviated New Drug Submission (ANDS) to the Canadian Ministry of Health requesting permission to manufacture and market a generic fixed-dose combination of emtricitabine and tenofovir disoproxil fumarate. In the notice, Teva alleges that three of the patents associated with Truvada are invalid, unenforceable and/or will not be infringed by Teva's manufacture, use or sale of a generic version of Truvada. In January 2012, we filed a lawsuit against Teva in Canadian Federal Court seeking an order of prohibition against approval of this ANDS. This lawsuit is currently scheduled for hearing in September 2013. If we are unsuccessful in obtaining the order of prohibition and Teva receives approval of their product, Teva will be able to launch generic version of our Truvada product “at risk” before expiry of our patents upon approval of their ANDS.

In December 2011, we received notice that Teva submitted an ANDS to the Canadian Ministry of Health requesting permission to manufacture and market a generic fixed-dose combination of emtricitabine, tenofovir disoproxil fumarate and efavirenz. In the notice, Teva alleges that three of our patents associated with Atripla and two of Merck's patents associated with Atripla are invalid, unenforceable and/or will not be infringed by Teva's manufacture, use or sale of a generic fixed-dose combination of emtricitabine, tenofovir disoproxil fumarate and efavirenz. In February 2012, we filed a lawsuit against Teva in Canadian Federal Court seeking an order of prohibition against approval of this ANDS.

In July 2012, we received notice that Lupin Limited (Lupin) submitted an ANDA to the FDA requesting permission to manufacture and market a generic version of Truvada. In the notice, Lupin alleges that four patents associated with emtricitabine and four patents associated with tenofovir disoproxil fumarate are invalid, unenforceable and/or will not be infringed by Lupin's manufacture, use or sale of a generic version of a fixed-dose combination of emtricitabine and tenofovir disoproxil fumarate. In August 2012, we filed a lawsuit against Lupin in U.S. District Court in New York for infringement of our patents.

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In July 2012, we received notice that Cipla Ltd. (Cipla) submitted an ANDA to the FDA requesting permission to manufacture and market a generic version of Emtriva and a generic version of Viread. In the notice, Cipla alleges that two patents associated with emtricitabine are invalid, unenforceable and/or will not be infringed by Cipla's manufacture, use or sale of a generic version of emtricitabine and four patents associated with tenofovir disoproxil fumarate are invalid, unenforceable and/or will not be infringed by Cipla's manufacture, use or sale of a generic version of tenofovir disoproxil fumarate. In August 2012, we filed lawsuits against Cipla in U.S. District Court in New York for infringement of our patents.

In August 2012, we received notice that Teva submitted an ANDS to the Canadian Ministry of Health requesting permission to manufacture and market a generic version of tenofovir disoproxil fumarate. In the notice, Teva alleges that two patents associated with Viread are invalid, unenforceable and/or will not be infringed by Teva's manufacture, use or sale of a generic version of Viread. In September 2012, we filed a lawsuit against Teva in Canadian Federal Court seeking an order of prohibition against approval of this ANDS. Also in August 2012, Teva filed an Impeachment Action in Canadian Federal Court seeking invalidation of our two Canadian patents associated with Viread. We are currently defending that Impeachment Action.

In October 2012, we received notice that Lupin submitted an ANDA to the FDA requesting permission to manufacture and market a generic version of Viread. In the notice, Lupin alleges that four patents associated tenofovir disoproxil fumarate are invalid, unenforceable and/or will not be infringed by Lupin's manufacture, use or sale of a generic version of tenofovir disoproxil fumarate. In October 2012, we filed a lawsuit against Lupin in U.S. District Court in New York for infringement of our patents.

Ranolazine

In June 2010, we received notice that Lupin submitted an ANDA to the FDA requesting permission to manufacture and market a generic version of sustained release ranolazine. In the notice, Lupin alleges that ten of the patents associated with Ranexa are invalid, unenforceable and/or will not be infringed by Lupin's manufacture, use or sale of a generic version of Ranexa. In July 2010, we filed a lawsuit against Lupin in U.S. District Court in New Jersey for infringement of our patents for Ranexa. The FDA cannot approve Lupin's ANDA until we receive a district court decision or upon the expiration of the court's automatic stay in July 2013. The court has scheduled the trial to begin in April 2013. If the court finds that none of the patents that protect our Ranexa formulation are infringed and/or that all are invalid and Lupin receives final approval of their product, Lupin will be able to launch generic version of our Ranexa product “at risk” upon issuance of that decision.

Adefovir disoproxil fumarate

In August 2010, we received notice that Sigmapharm Labs (Sigmapharm) submitted an ANDA to the FDA requesting permission to manufacture and market a generic adefovir dipivoxil. In the notice, Sigmapharm alleges that both of the patents associated with Hepsera are invalid, unenforceable and/or will not be infringed by Sigmapharm's manufacture, use or sale of a generic version of Hepsera. In September 2010, we filed a lawsuit against Sigmapharm in U.S. District Court in New Jersey for infringement of our patents. The FDA cannot approve Sigmapharm's ANDA until we receive a district court decision or upon the expiration of the court's automatic stay in February 2013. As a result of the recent invalidation of the patents protecting entecavir and due to declining sales of Hepsera in the United States, in March 2013, we granted Sigmapharm a Covenant Not to Sue if it launches a generic version of Hepsera prior to the expiration of our patents and then filed a motion to dismiss all claims in the lawsuit. Once Sigmapharm obtains FDA approval of its product, it may launch its generic product.

One of the patents challenged by Sigmapharm was also challenged by Ranbaxy, Inc. (Ranbaxy) pursuant to a notice received in October 2010. The patent challenged by Ranbaxy expires in July 2018. We do not anticipate filing a lawsuit against Ranbaxy.

Tamiflu

In February 2011, we received notice that Natco Pharma Ltd. (Natco) submitted an ANDA to the FDA requesting permission to manufacture and market a generic oseltamivir phosphate. In the notice, Natco alleges that one of the patents associated with Tamiflu is invalid, unenforceable and/or will not be infringed by Natco's manufacture, use or sale of a generic version of Tamiflu. In March 2011, we and F. Hoffmann-La Roche Ltd. (Roche) filed a lawsuit against Natco in U.S. District Court in New Jersey for infringement of one of the patents associated with Tamiflu. In December 2012, the court issued a ruling in favor of Gilead and Roche, that our patent is not invalid for the reasons stated in Natco's notice letter. Natco has the right to appeal this decision.

We cannot predict the ultimate outcome of these actions, and we may spend significant resources enforcing and defending these patents. If we are unsuccessful in these lawsuits, some or all of our original claims in the patents may be narrowed or invalidated and the patent protection for Atripla, Truvada, Viread Ranexa and Tamiflu in the United States and Atripla, Truvada and Viread in Canada could be substantially shortened. Further, if all of the patents covering one or more products are invalidated, the FDA or Canadian Ministry of Health could approve the requests to manufacture a generic version of such products in the United States or Canada, respectively, prior to the expiration date of those patents. The sale of generic versions

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of these products earlier than their patent expiration would have a significant negative effect on our revenues and results of operations.

Department of Justice Investigation

In June 2011, we received a subpoena from the U.S. Attorney's Office for the Northern District of California requesting documents related to the manufacture, and related quality and distribution practices, of Complera, Atripla, Truvada, Viread, Emtriva, Hepsera and Letairis. We have been cooperating and will continue to cooperate with this governmental inquiry.

Interference Proceedings and Litigation with Idenix Pharmaceuticals, Inc.

In February 2012, we received notice that the U.S. Patent and Trademark Office (PTO) had declared an Interference between our U.S. Patent No. 7,429,572 and Idenix Pharmaceuticals, Inc.'s (Idenix) pending patent application no. 12/131868. An Interference is an administrative proceeding before the PTO designed to determine who was the first to invent the subject matter being claimed by both parties. Our patent covers metabolites of sofosbuvir and RG7128. Idenix is attempting to claim a class of compounds, including these metabolites, in their pending patent application. In the course of this proceeding, both parties will be called upon to submit evidence of the date they conceived of their respective inventions. The Interference will determine who was first to invent these compounds and therefore who is entitled to the patent claiming these compounds. In March 2013, the PTO Patent Trials and Appeal Board (the Board) determined that Idenix is not entitled to the benefit of any of their early application filing dates because none of those patent applications taught how to make the compounds in dispute. The Board also determined that we are entitled to the filing date of its earliest application. As a result, the Board determined that we were first to file its patent application on the compounds in dispute and is therefore the “senior party” in the interference. In the second phase of the interference, the Board will determine who was first to invent the compounds. The party who is deemed first to invent will prevail in the interference proceeding. Idenix bears the burden of establishing that despite their much later patent application filing date, they were nevertheless first to invent the compounds in dispute. In order to prove they were first to invent, Idenix must prove that they were first to conceive of a compound within the scope of those in dispute, namely that (1) the named inventors had identified the structure, a method of making and a use for a disputed compound and (2) that Idenix worked diligently from their earliest conception date until they made and tested the compound or filed their last application in 2008.

If the Board determines that Idenix was first to invent and is entitled to these patent claims and it is determined that we have infringed those claims, we may be required to obtain a license from and pay royalties to Idenix to commercialize sofosbuvir and RG7128. Any determination by the Board can be appealed by either party to U.S. Federal Court.

We believe the Idenix application involved in the Interference and similar U.S. and foreign patents claiming the same compounds and metabolites are invalid. As a result, we filed an Impeachment Action in Canadian Federal Court to invalidate the Idenix CA2490191 patent, which is the Canadian patent that corresponds to the Idenix U.S. Patent No. 7608600 and the Idenix patent application that is the subject of the Interference. Idenix has now asserted that our Canadian Patent No. 2527657, corresponding to the '572 patent in the Interference, is invalid. We filed a similar legal action in the Federal Court of Norway seeking to invalidate Idenix's corresponding Norwegian patent. We filed a similar legal action in the Federal Court of Australia seeking to invalidate the corresponding Australian patent. We may bring similar action in other countries in 2013. Idenix has not been awarded patents on these compounds in European countries, Japan or China. In the event such patents issue, we expect to challenge them in proceedings similar to those we invoked in Canada, Norway and Australia.

Arbitration with F. Hoffman-La Roche Ltd and Hoffman-La Roche Inc.

Gilead (as successor to Pharmasset, Inc. (Pharmasset)) is a party to an October 29, 2004 collaboration agreement with Roche and Hoffman-La Roche Inc. The agreement granted Roche rights to develop PSI-6130, a cytidine analog, and its prodrugs, for the treatment of chronic HCV infection. The collaborative research efforts under the agreement ended on December 31, 2006. Roche later asked Pharmasset to consider whether Roche may have contributed to the inventorship of sofosbuvir and whether Pharmasset has complied with the confidentiality provisions of the collaboration agreement. Pharmasset advised us that it carefully considered the issues raised by Roche and that it believed any such issues are without merit. We have also considered these issues and reached the same conclusion. In March 2013, Roche initiated an arbitration against us and Pharmasset, predecessor to Gilead Pharmasset LLC, regarding the collaboration agreement. In the demand, Roche asserts that it has an exclusive license to sofosbuvir pursuant to the collaboration agreement because sofosbuvir, a prodrug of a uridine monophosphate analog, is allegedly a prodrug of PSI-6130. Roche further claims that, because it has exclusive rights to sofosbuvir, it also has an exclusive license to a patent covering sofosbuvir, and that we will infringe that patent by selling and offering for sale products containing sofosbuvir. Gilead and Gilead Pharmasset LLC filed their response to Roche's demand in April 2013. We believe Roche's claim is without merit. However, if Roche were to successfully establish exclusive rights to sofosbuvir, our expected revenues and earnings from the sale of sofosbuvir could be adversely affected.

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Contract Arbitration with Jeremy Clark

In March 2012, Jeremy Clark, a former employee of Pharmasset, which we acquired in January 2012, and inventor of U.S. Patent No. 7,429,572, filed a demand for arbitration in his lawsuit against Pharmasset and Dr. Raymond Schinazi. Mr. Clark initially filed the lawsuit against Pharmasset and Dr. Schinazi in Alabama District Court in February 2008 seeking to void the assignment provision in his employment agreement and assert ownership of U.S. Patent No. 7,429,572, which claims metabolites of sofosbuvir and RG7128. In December 2008, the court ordered a stay of the litigation pending the outcome of an arbitration proceeding required by Mr. Clark's employment agreement. Instead of proceeding with arbitration, Mr. Clark filed two additional lawsuits in September 2009 and June 2010, both of which were subsequently dismissed by the court. In September 2010, Mr. Clark filed a motion seeking reconsideration of the court's December 2008 order which was denied by the court. In December 2011, Mr. Clark filed a motion to appoint a special prosecutor. In February 2012, the Alabama Court issued an order requiring Mr. Clark to enter arbitration or risk dismissal of his case. Mr. Clark filed a demand for arbitration in March 2012. The arbitration panel held a hearing date in April 2013. We anticipate a decision in this matter as early as June 2013. We cannot predict the outcome of the arbitration. If Mr. Clark's prior assignment of this patent to Pharmasset is voided by the arbitration panel, and he is ultimately found to be the owner of the 7,429,572 patent and it is determined that we have infringed the patent, we may be required to obtain a license from and pay royalties to Mr. Clark to commercialize sofosbuvir and RG7128.

Other Matters

We are a party to various legal actions that arose in the ordinary course of our business. We do not believe that any of these legal actions will have a material adverse impact on our consolidated business, financial position or results of operations.

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ITEM 1A. RISK FACTORS

In evaluating our business, you should carefully consider the following risks in addition to the other information in this Quarterly Report on Form 10-Q. A manifestation of any of the following risks could materially and adversely affect our business, results of operations and financial condition. We note these factors for investors as permitted by the Private Securities Litigation Reform Act of 1995. It is not possible to predict or identify all such factors and, therefore, you should not consider the following risks to be a complete statement of all the potential risks or uncertainties that we face.

The public announcement of data from clinical studies evaluating sofosbuvir and the fixed-dose combination of sofosbuvir/ledipasvir in HCV-infected patients is likely to cause significant volatility in our stock price. If the development or approval of sofosbuvir alone or in combination with ledipasvir is delayed or discontinued, our stock price could decline significantly.

During 2013, we expect to receive a significant amount of data from clinical trials evaluating sofosbuvir, an investigational nucleotide analog we acquired through our purchase of Pharmasset, Inc. (Pharmasset), alone or in combination with other direct acting antivirals in hepatitis C virus (HCV)-infected individuals across all genotypes.

In April 2013, we filed a new drug application (NDA) with the U.S. Food and Drug Administration (FDA) for sofosbuvir. The data submitted in this NDA support the use of sofosbuvir and ribavirin as an all-oral therapy for patients with genotype 2 and 3 HCV infection, and of sofosbuvir in combination with ribavirin and peg-IFN for treatment-naïve patients with genotype 1, 4, 5 and 6 HCV infection. There is risk that the FDA may not approve sofosbuvir in a timely manner or at all, and that any marketing approval, if granted, may have significant limitations on their use.

In parallel, we are also advancing a fixed-dose combination of sofosbuvir/ledipasvir (formerly GS-5885) for the treatment of genotype 1 patients. Our NDA for the fixed dose combination of sofosbuvir/ledipasvir will be supported by two clinical trials. The first study, named ION-1, evaluates the fixed-dose combination of sofosbuvir/ledipasvir with and without ribavirin for either 12 or 24 weeks in treatment-naïve genotype 1 infected patients. Pending a review of results from the two 12-week arms of an initial enrollment of 200 patients, by the second quarter of 2013, we expect to enroll additional patients in the ION-1 study to assess the fixed dose combination of sofosbuvir/ledipasvir in a total of 800 individuals. In January 2013, we also started screening patients for a Phase 3 study, named ION-2, evaluating the fixed-dose combination with ribavirin for 12 weeks and with and without ribavirin for 24 weeks of therapy among treatment-experienced genotype 1 HCV patients.

We are also conducting a Phase 2 study, named LONESTAR, evaluating sofosbuvir/ledipasvir for 12 weeks and sofosbuvir/ledipasvir with and without RBV for 8 weeks among genotype 1 treatment-naïve patients. Two additional arms in this trial will evaluate sofosbuvir/ledipasvir with and without RBV for 12 weeks among treatment-experienced genotype 1 patients who had previously received a protease inhibitor-containing regimen. Based on interim data from the Phase 2 LONESTAR study, in April 2013, we initiated a new Phase 3 study, named ION-3, evaluating the fixed-dose combination of sofosbuvir/ledipasvir for eight weeks with and without ribavirin and for 12 weeks without ribavirin in 600 non-cirrhotic, treatment-naïve genotype 1 HCV-infected patients.

The announcement of data from our clinical studies evaluating sofosbuvir and the fixed-dose combination of sofosbuvir/ledipasvir is likely to cause significant volatility in our stock price. The announcement of any negative or unexpected data or the discontinuation of development of sofosbuvir or the fixed-dose combination of sofosbuvir/ledipasvir or any delay in our anticipated timelines for obtaining regulatory approval in the United States or European Union will likely cause our stock price to decline significantly.

A substantial portion of our revenues is derived from sales of our HIV products, particularly Atripla and Truvada. If we are unable to maintain or continue increasing sales of these products, our results of operations may be adversely affected.

We are currently dependent on sales of our products for the treatment of HIV infection, particularly Atripla and Truvada, to support our existing operations. Our HIV products contain tenofovir disoproxil fumarate and/or emtricitabine, which belong to the nucleoside class of antiviral therapeutics. Were the treatment paradigm for HIV to change, causing nucleoside-based therapeutics to fall out of favor, or if we were unable to maintain or continue increasing our HIV product sales, our results of operations would likely suffer and we would likely need to scale back our operations, including our spending on research and development (R&D) efforts. For the three months ended March 31, 2013, Atripla and Truvada product sales together were $1.58 billion, or 62% of our total revenues. We may not be able to sustain or increase the growth rate of sales of our HIV products, especially Stribild, Complera/Eviplera, Atripla and Truvada, for any number of reasons including, but not limited to, the following:

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• As our HIV products are used over a longer period of time in many patients and in combination with other products, and additional studies are conducted, new issues with respect to safety, resistance and interactions with other drugs may arise, which could cause us to provide additional warnings or contraindications on our labels, narrow our approved indications or halt sales of a product, each of which could reduce our revenues.

• As our HIV products mature, private insurers and government payers often reduce the amount they will reimburse patients for these products, which increases pressure on us to reduce prices.

• A large part of the market for our HIV products consists of patients who are already taking other HIV drugs. If we are not successful in encouraging physicians to change patients' regimens to include our HIV products, the sales of our HIV products will be limited.

• As generic HIV products are introduced into major markets, our ability to maintain pricing and market share may be affected.

If we fail to commercialize new products or expand the indications for existing products, our prospects for future revenues may be adversely affected.

If we do not introduce new products to market or increase sales of our existing products, we will not be able to increase or maintain our total revenues and continue to expand our R&D efforts. Drug development is inherently risky and many product candidates fail during the drug development process. For example, in April 2013, we announced our decision to terminate our Phase 3 clinical trial of aztreonam for inhalation solution for the treatment of bronchiectasis. In addition, our new drug applications for elvitegravir for the treatment of HIV in treatment-experienced patients; cobicistat, a pharmacoenhancing or “boosting” agent, and sofosbuvir for the treatment of HCV may not be approved by the FDA, EMA or other foreign regulatory authorities on a timely basis, or at all. Even if marketing approval is granted for the product, there may be significant limitations on their use. Further, we may be unable to file our marketing applications for new products, including sofosbuvir and the fixed-dose combination of sofosbuvir/ledipasvir in the currently anticipated timelines and marketing approval for the products may not be granted.

Because Congress did not agree to a package of tax and federal spending proposals on January 1, 2013, an automatic reduction in federal spending or “sequestration” took effect on March 1, 2013. Under sequestration, across-the-board cuts will be implemented, which is expected to effect the operations of governmental agencies, including the FDA. As a result, the FDA may be unable to review and approve NDAs in the currently anticipated timelines. Any significant delay in the timing of our anticipated product approvals may reduce our anticipated future revenue and earnings and could negatively affect our stock price.

Our results of operations will be adversely affected by current and potential future healthcare reforms.

Legislative and regulatory changes to government prescription drug procurement and reimbursement programs occur relatively frequently in the United States and foreign jurisdictions. In March 2010, healthcare reform legislation was adopted in the United States. As a result, we are required to further rebate or discount products reimbursed or paid for by various public payers, including Medicaid and other entities eligible to purchase discounted products through the 340B Drug Pricing Program under the Public Health Service Act, such as AIDS Drug Assistance Programs (ADAPs). As a result of the 2010 legislation, the discounts, rebates and fees that impacted us include:

• our minimum base rebate amount owed to Medicaid on products reimbursed by Medicaid increased by 8%, and the discounts or rebates we owe to ADAPs and other Public Health Service entities which reimburse or purchase our products also increased by 8%;

• we are required to extend rebates to patients receiving our products through Medicaid managed care organizations;

• we are required to provide a 50% discount on products sold to patients while they are in the Medicare Part D “donut hole;” and

• we, along with other pharmaceutical manufacturers of branded drug products, were required to pay a portion of a new industry fee (also known as the pharmaceutical excise tax) of $2.8 billion for 2012, calculated based on select government sales during the 2010 calendar year as a percentage of total industry government sales.

The amount of the industry fee imposed on the pharmaceutical industry as a whole increased to $2.8 billion in 2012 and 2013, with additional increases over the next several years to a peak of $4.1 billion per year in 2018, and then decrease to $2.8 billion in 2019 and thereafter. As the amount of the industry fee increases, our product sales increase and drug patents expire on major drugs of other companies, we expect our portion of the excise tax to increase as well. We estimate our portion of the pharmaceutical excise tax to be approximately $100-$120 million in 2013, compared to approximately $85 million in 2012. The excise tax is not tax deductible. Further, even though not addressed in the healthcare reform legislation, discussions continue at the federal level on legislation that would either allow or require the federal government to directly negotiate price concessions from pharmaceutical manufacturers or set minimum requirements for Medicare Part D pricing.

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In addition, state Medicaid programs could request additional supplemental rebates on our products as a result of the increase in the federal base Medicaid rebate. Private insurers could also use the enactment of these increased rebates to exert pricing pressure on our products, and to the extent that private insurers or managed care programs follow Medicaid coverage and payment developments, the adverse effects may be magnified by private insurers adopting lower payment schedules.

Our existing products are subject to reimbursement from government agencies and other third parties. Pharmaceutical pricing and reimbursement pressures may reduce profitability.

Successful commercialization of our products depends, in part, on the availability of governmental and third-party payer reimbursement for the cost of such products and related treatments. Government health administration authorities, private health insurers and other organizations generally provide reimbursement. In the United States, the European Union and other significant or potentially significant markets for our products and product candidates, government authorities and third-party payers are increasingly attempting to limit or regulate the price of medical products and services, particularly for new and innovative products and therapies, which has resulted in lower average selling prices.

A significant portion of our sales of the majority of our products are subject to significant discounts from list price and rebate obligations. In the United States, state ADAPs, which purchase a significant portion of our HIV products, rely on federal, supplemental federal and state funding to help fund purchases of our products. Given the current economic downturn, we have experienced a shift in our payer mix as patients previously covered by private insurance move to public reimbursement programs that require rebates or discounts from us or as patients previously covered by one public reimbursement program move to another public reimbursement program that requires greater rebates or discounts from us. As a result of this shift, revenue growth may be lower than prescription growth. Effective March 1, 2013, an automatic reduction in federal spending or “sequestration” is in effect. Under sequestration, across-the-board cuts will be implemented and could reduce the amount of federal and state funds to support ADAP programs. If federal and state funds are not available in amounts sufficient to support the number of patients that rely on ADAPs, sales of our HIV products could be negatively impacted which would reduce our revenues. For example, during the first quarter of 2011, the state budget crisis in Florida led to a temporary movement of patients who were previously covered by Florida's ADAP into industry-supported patient assistance programs. In prior quarters, because of the insufficiency of federal and state funds and as many states reduced eligibility criteria, we saw an increase in the number of patients on state ADAP wait lists, and we may see similar increases in future periods as a result of any reduction in federal and state ADAP support resulting from the sequestration. Until these patients are enrolled in ADAP, they generally receive product from industry-supported patient assistance programs or are unable to access treatment. The increased emphasis on managed healthcare in the United States and on country and regional pricing and reimbursement controls in the European Union will put additional pressure on product pricing, reimbursement and usage, which may adversely affect our product sales and profitability. These pressures can arise from rules and practices of managed care groups, judicial decisions and governmental laws and regulations related to Medicare, Medicaid and healthcare reform, pharmaceutical reimbursement policies and pricing in general.

In Europe, the success of our commercialized products, and any other product candidates we may develop, will depend largely on obtaining and maintaining government reimbursement, because in many European countries patients are unlikely to use prescription drugs that are not reimbursed by their governments. In addition, negotiating prices with governmental authorities can delay commercialization by 12 months or more. Reimbursement policies may adversely affect our ability to sell our products on a profitable basis. In many international markets, governments control the prices of prescription pharmaceuticals, including through the implementation of reference pricing, price cuts, rebates, revenue-related taxes and profit control, and they expect prices of prescription pharmaceuticals to decline over the life of the product or as volumes increase.

Recently, many countries in the European Union have increased the amount of discounts required on our products, and these efforts could continue as countries attempt to manage healthcare expenditures, especially in light of the severe fiscal and debt crises experienced by many countries in the European Union. For example, in June 2010, Spain imposed an incremental discount on all branded drugs and in August 2010, Germany increased the rebate on prescription pharmaceuticals. As generic drugs come to market, we may face price decreases for our products in some countries in the European Union. Further, cost containment pressures in the European Union could lead to delays in the treatment of patients and also delay pricing approval, which could negatively impact the commercialization of new products.

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Approximately 40-45% of our product sales occur outside the United States, and currency fluctuations and hedging expenses may cause our earnings to fluctuate, which could adversely affect our stock price.

Because a significant percentage of our product sales are denominated in foreign currencies, primarily the Euro, we face exposure to adverse movements in foreign currency exchange rates. When the U.S. dollar strengthens against these foreign currencies, the relative value of sales made in the respective foreign currency decreases. Conversely, when the U.S. dollar weakens against these currencies, the relative value of such sales increases. Overall, we are a net receiver of foreign currencies and, therefore, benefit from a weaker U.S. dollar and are adversely affected by a stronger U.S. dollar relative to those foreign currencies in which we transact significant amounts of business.

We use foreign currency exchange forward and option contracts to hedge a percentage of our forecasted international sales, primarily those denominated in the Euro. We also hedge certain monetary assets and liabilities denominated in foreign currencies, which reduces but does not eliminate our exposure to currency fluctuations between the date a transaction is recorded and the date that cash is collected or paid. We cannot predict future fluctuations in the foreign currency exchange rate of the U.S. dollar. If the U.S. dollar appreciates significantly against certain currencies and our hedging program does not sufficiently offset the effects of such appreciation, our results of operations will be adversely affected and our stock price may decline.

Additionally, the expenses that we recognize in relation to our hedging activities can also cause our earnings to fluctuate. The level of hedging expenses that we recognize in a particular period is impacted by the changes in interest rate spreads between the foreign currencies that we hedge and the U.S. dollar.

Our inability to accurately estimate demand for our products, as well as sales fluctuations as a result of inventory levels held by wholesalers, pharmacies and non-retail customers make it difficult for us to accurately forecast sales and may cause our earnings to fluctuate, which could adversely affect our financial results and our stock price.

In quarter ended March 31, 2013, approximately 80% of our product sales in the United States were to three wholesalers, Cardinal Health, Inc., McKesson Corp. and AmerisourceBergen Corp. The U.S. wholesalers with whom we have entered into inventory management agreements make estimates to determine end user demand and may not be completely effective in matching their inventory levels to actual end user demand. As a result, changes in inventory levels held by those wholesalers can cause our operating results to fluctuate unexpectedly if our sales to these wholesalers do not match end user demand. In addition, inventory is held at retail pharmacies and other non-wholesale locations with whom we have no inventory management agreements and no control over buying patterns. Adverse changes in economic conditions or other factors may cause retail pharmacies to reduce their inventories of our products, which would reduce their orders from wholesalers and, consequently, the wholesalers' orders from us, even if end user demand has not changed. For example, during the fourth quarter of 2012, our wholesalers increased their inventory levels for our antiviral products. In the first quarter of 2013, our wholesalers drew down on their inventory such that inventory levels for our antiviral products moved to the lower end of the contractual boundaries set by our inventory management agreements. As inventory in the distribution channel fluctuates from quarter to quarter, we may continue to see fluctuations in our earnings and a mismatch between prescription demand for our products and our revenues

In addition, the non-retail sector in the United States, which includes government institutions, including state ADAPs, correctional facilities and large health maintenance organizations, tends to be even less consistent in terms of buying patterns and often causes quarter over quarter fluctuations that do not necessarily mirror patient demand. Federal and state budget pressures, including sequestration, as well as the annual grant cycles for federal and state ADAP funds, may cause ADAP purchasing patterns to not reflect patient demand. For example, similar to first quarters of prior years, in the first quarter of 2013, we observed large non-retail purchases by a number of state ADAPs which exceeded patient demand. We believe such purchases were driven by the grant cycle for federal ADAP funds. Given the uncertainty about the timing and amount of federal funding for ADAP for the 2013 year, we expect to see reduced purchasing by ADAPs until the Ryan White Funds are fully communicated. As a result, we expect to continue to experience fluctuations in the purchasing patterns of our non-retail customers which may result in fluctuations in our product sales, revenues and earnings in the future. In light of the global economic downturn and budget crises faced by many European countries, we have observed variations in purchasing patterns induced by cost containment measures in Europe. We believe these measures have caused some government agencies and other purchasers to reduce inventory of our products in the distribution channels, which has decreased our revenues and caused fluctuations in our product sales and earnings. We may continue to see this trend in the future.

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We face significant competition.

We face significant competition from large pharmaceutical and biotechnology companies, most of whom have substantially greater resources than we do. In addition, our competitors have more products and have operated in the fields in which we compete for longer than we have. Our HIV products compete primarily with products from the joint venture established by GlaxoSmithKline Inc. (GSK) and Pfizer Inc. (Pfizer) which markets fixed-dose combination products that compete with Stribild, Complera/Eviplera, Atripla and Truvada. For example, lamivudine, marketed by this joint venture, is competitive with emtricitabine, the active pharmaceutical ingredient of Emtriva and a component of Complera/Eviplera, Atripla and Truvada.

We also face competition from generic HIV products. In May 2010, the compound patent covering Epivir (lamivudine) itself expired in the United States, and generic lamivudine is now available in the United States, Spain, Portugal and Italy. We expect that generic versions of lamivudine will be launched in other countries within the European Union. In May 2011, a generic version of Combivir (lamivudine and zidovudine) was approved and was recently launched in the United States. In addition, in late 2011, generic tenofovir also became available in Turkey, which resulted in an increase in the rebate for Viread in Turkey. We currently also expect competition from a generic version of Sustiva (efavirenz), a component of our Atripla, to be available in Europe and Canada in 2013 and the United States in 2014, which may negatively impact sales of our HIV products. We also expect the launch of dolutegravir, an integrase inhibitor, in the fourth quarter of 2013 by GSK which could impact the sales of our HIV products.

For Viread and Hepsera for treatment of chronic HBV, we compete primarily with products produced by GSK, Bristol-Myers Squibb Company (BMS) and Novartis Pharmaceuticals Corporation (Novartis) in the United States, the European Union and China. For AmBisome, we compete primarily with products produced by Merck & Co., Inc. (Merck) and Pfizer. In addition, we are aware of at least three lipid formulations that claim similarity to AmBisome becoming available outside of the United States, including the possible entry of such formulations in Greece and Taiwan. These formulations may reduce market demand for AmBisome. Furthermore, the manufacture of lipid formulations of amphotericin B is very complex and if any of these formulations are found to be unsafe, sales of AmBisome may be negatively impacted by association. Letairis competes directly with a product produced by Actelion Pharmaceuticals US, Inc. and indirectly with pulmonary arterial hypertension products from United Therapeutics Corporation and Pfizer. Ranexa competes predominantly with generic compounds from three distinct classes of drugs, beta-blockers, calcium channel blockers and long-acting nitrates for the treatment of chronic angina in the United States. Cayston competes with a product marketed by Novartis. Tamiflu competes with products sold by GSK and generic competitors.

In addition, a number of companies are pursuing the development of technologies which are competitive with our existing products or research programs. These competing companies include specialized pharmaceutical firms and large pharmaceutical companies acting either independently or together with other pharmaceutical companies. Furthermore, academic institutions, government agencies and other public and private organizations conducting research may seek patent protection and may establish collaborative arrangements for competitive products or programs.

If significant safety issues arise for our marketed products or our product candidates, our future sales may be reduced, which would adversely affect our results of operations.

The data supporting the marketing approvals for our products and forming the basis for the safety warnings in our product labels were obtained in controlled clinical trials of limited duration and, in some cases, from post-approval use. As our products are used over longer periods of time by many patients with underlying health problems, taking numerous other medicines, we expect to continue to find new issues such as safety, resistance or drug interaction issues, which may require us to provide additional warnings or contraindications on our labels or narrow our approved indications, each of which could reduce the market acceptance of these products.

Our product Letairis, which was approved by the FDA in June 2007, is a member of a class of compounds called endothelin receptor antagonists (ERAs) which pose specific risks, including serious risks of birth defects. Because of these risks, Letairis is available only through the Letairis Education and Access Program (LEAP), a restricted distribution program intended to help physicians and patients learn about the risks associated with the product and assure appropriate use of the product. As the product is used by additional patients, we may discover new risks associated with Letairis which may result in changes to the distribution program and additional restrictions on the use of Letairis which may decrease demand for the product.

Regulatory authorities have been moving towards more active and transparent pharmacovigilance and are making greater amounts of stand-alone safety information directly available to the public through websites and other means, e.g. periodic safety update report summaries, risk management plan summaries and various adverse event data. Safety information, without the appropriate context and expertise, may be misinterpreted and lead to misperception or legal action which may potentially cause our product sales or stock price to decline.

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Further, if serious safety, resistance or drug interaction issues arise with our marketed products, sales of these products could be limited or halted by us or by regulatory authorities and our results of operations would be adversely affected.

Our operations depend on compliance with complex FDA and comparable international regulations. Failure to obtain broad approvals on a timely basis or to maintain compliance could delay or halt commercialization of our products.

The products we develop must be approved for marketing and sale by regulatory authorities and, once approved, are subject to extensive regulation by the FDA, the EMA and comparable regulatory agencies in other countries. We are continuing clinical trials for Stribild, Complera/Eviplera, Atripla, Truvada, Viread, Hepsera, Emtriva, Letairis, Ranexa, AmBisome and Cayston for currently approved and additional uses. We anticipate that we will file for marketing approval in additional countries and for additional indications and products over the next several years. These products may fail to receive such marketing approvals on a timely basis, or at all.

Further, our marketed products and how we manufacture and sell these products are subject to extensive regulation and review. Discovery of previously unknown problems with our marketed products or problems with our manufacturing or promotional activities may result in restrictions on our products, including withdrawal of the products from the market. If we fail to comply with applicable regulatory requirements, including those related to promotion and manufacturing, we could be subject to penalties including fines, suspensions of regulatory approvals, product recalls, seizure of products and criminal prosecution.

For example, under FDA rules, we are often required to conduct post-approval clinical studies to assess a known serious risk, signals of serious risk or to identify an unexpected serious risk and implement a Risk Evaluation and Mitigation Strategy for our products, which could include a medication guide, patient package insert, a communication plan to healthcare providers or other elements as the FDA deems are necessary to assure safe use of the drug, which could include imposing certain restrictions on the distribution or use of a product. Failure to comply with these or other requirements, if imposed on a sponsor by the FDA, could result in significant civil monetary penalties and our operating results may be adversely affected.

The results and anticipated timelines of our clinical trials are uncertain and may not support continued development of a product pipeline, which would adversely affect our prospects for future revenue growth.

We are required to demonstrate the safety and efficacy of products that we develop for each intended use through extensive preclinical studies and clinical trials. The results from preclinical and early clinical studies do not always accurately predict results in later, large-scale clinical trials. Even successfully completed large-scale clinical trials may not result in marketable products. If any of our product candidates fails to achieve its primary endpoint in clinical trials, if safety issues arise or if the results from our clinical trials are otherwise inadequate to support regulatory approval of our product candidates, commercialization of that product candidate could be delayed or halted. For example, in April 2013, we announced our decision to terminate our Phase 3 clinical trial of aztreonam for inhalation solution for the treatment of bronchiectasis. In addition, we may also face challenges in clinical trial protocol design. If the clinical trials for any of the product candidates in our pipeline are delayed or terminated, our prospects for future revenue growth would be adversely impacted. For example, we face numerous risks and uncertainties with our product candidates, including sofosbuvir and the fixed-dose combination of sofosbuvir/ledipasvir for the treatment of hepatitis C; aranolazine for the treatment of incomplete revascularization post-percutaneous coronary intervention and type II diabetes; and idelalisib for the treatment of chronic lymphocytic leukemia, each currently in Phase 3 clinical trials, that could prevent completion of development of these product candidates. These risks include our ability to enroll patients in clinical trials, the possibility of unfavorable results of our clinical trials, the need to modify or delay our clinical trials or to perform additional trials and the risk of failing to obtain FDA and other regulatory body approvals. As a result, our product candidates may never be successfully commercialized. Further, we may make a strategic decision to discontinue development of our product candidates if, for example, we believe commercialization will be difficult relative to other opportunities in our pipeline. If these programs and others in our pipeline cannot be completed on a timely basis or at all, then our prospects for future revenue growth may be adversely impacted. In addition, clinical trials involving our commercial products could raise new safety issues for our existing products, which could in turn decrease our revenues and harm our business.

Due to our reliance on third-party contract research organizations to conduct our clinical trials, we are unable to directly control the timing, conduct, expense and quality of our clinical trials.

We extensively outsource our clinical trial activities and usually perform only a small portion of the start-up activities in-house. We rely on independent third-party contract research organizations (CROs) to perform most of our clinical studies, including document preparation, site identification, screening and preparation, pre-study visits, training, program management and bioanalytical analysis. Many important aspects of the services performed for us by the CROs are out of our direct control. If there is any dispute or disruption in our relationship with our CROs, our clinical trials may be delayed. Moreover, in our regulatory submissions, we rely on the quality and validity of the clinical work performed by third-party CROs. If any of our

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CROs' processes, methodologies or results were determined to be invalid or inadequate, our own clinical data and results and related regulatory approvals could be adversely impacted.

Expenses associated with clinical trials may cause our earnings to fluctuate, which could adversely affect our stock price.

The clinical trials required for regulatory approval of our products, as well as clinical trials we are required to conduct after approval, are very expensive. It is difficult to accurately predict or control the amount or timing of these expenses from quarter to quarter, and the FDA and/or other regulatory agencies may require more clinical testing than we originally anticipated. Uneven and unexpected spending on these programs, including on the clinical trials that will be necessary to advance sofosbuvir, the fixed-dose combination of sofosbuvir/ledipasvir and our other product candidates for the treatment of HCV and oncology, may cause our operating results to fluctuate from quarter to quarter and volatility in our stock price.

We depend on relationships with other companies for sales and marketing performance, development and commercialization of product candidates and revenues. Failure to maintain these relationships, poor performance by these companies or disputes with these companies could negatively impact our business.

We rely on a number of significant collaborative relationships with major pharmaceutical companies for our sales and marketing performance in certain territories. These include collaborations with BMS for Atripla in the United States, Europe and Canada; F. Hoffmann-La Roche Ltd. (together with Hoffmann-La Roche Inc., Roche) for Tamiflu worldwide; and GSK for ambrisentan in territories outside of the United States. In some countries, we rely on international distributors for sales of Truvada, Viread, Hepsera, Emtriva and AmBisome. Some of these relationships also involve the clinical development of these products by our partners. Reliance on collaborative relationships poses a number of risks, including the risk that:

• we are unable to control the resources our corporate partners devote to our programs or products;

• disputes may arise with respect to the ownership of rights to technology developed with our corporate partners;

• disagreements with our corporate partners could cause delays in, or termination of, the research, development or commercialization of product candidates or result in litigation or arbitration;

• contracts with our corporate partners may fail to provide significant protection or may fail to be effectively enforced if one of these partners fails to perform;

• our corporate partners have considerable discretion in electing whether to pursue the development of any additional products and may pursue alternative technologies or products either on their own or in collaboration with our competitors;

• our corporate partners with marketing rights may choose to pursue competing technologies or to devote fewer resources to the marketing of our products than they do to products of their own development; and

• our distributors and our corporate partners may be unable to pay us, particularly in light of current economic conditions.

Given these risks, there is a great deal of uncertainty regarding the success of our current and future collaborative efforts. If these efforts fail, our product development or commercialization of new products could be delayed or revenues from products could decline.

We also rely on collaborative relationships with major pharmaceutical companies for development and commercialization of certain product candidates. Gilead (as successor to Pharmasset) is a party to an October 29, 2004 collaboration agreement with Roche. The agreement granted Roche rights to develop PSI-6130, a cytidine analog, and its prodrugs, for the treatment of chronic HCV infection. The collaborative research efforts under the agreement ended on December 31, 2006. Roche later asked Pharmasset to consider whether Roche may have contributed to the inventorship of sofosbuvir and whether Pharmasset has complied with the confidentiality provisions of the collaboration agreement. Pharmasset advised us that it carefully considered the issues raised by Roche and that it believed any such issues are without merit. We have also considered these issues and reached the same conclusion. In March 2013, Roche initiated an arbitration against us and Pharmasset, predecessor to Gilead Pharmasset LLC, regarding the collaboration agreement. In the demand, Roche asserts that it has an exclusive license to sofosbuvir pursuant to the collaboration agreement because sofosbuvir, a prodrug of a uridine monophosphate analog, is allegedly a prodrug of PSI-6130. Roche further claims that, because it has exclusive rights to sofosbuvir, it also has an exclusive license to a patent covering sofosbuvir, and that we will infringe that patent by selling and offering for sale products containing sofosbuvir. Gilead and Gilead Pharmasset LLC filed their response to Roche's demand in April 2013. We believe Roche's claim is without merit. However, if Roche were to successfully establish exclusive rights to sofosbuvir, our expected revenues and earnings from the sale of sofosbuvir could be adversely affected.

Under our April 2002 licensing agreement with GSK, we gave GSK the right to control clinical and regulatory development and commercialization of Hepsera in territories in Asia, Africa and Latin America. These include major markets for Hepsera, such as China, Japan, Taiwan and South Korea. In November 2009, we entered into an agreement with GSK that

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provided GSK with exclusive commercialization rights and registration responsibilities for Viread for the treatment of chronic HBV in China. In October 2010, we granted similar rights to GSK in Japan and Saudi Arabia. The success of Hepsera and Viread for the treatment of chronic HBV in these territories depends almost entirely on the efforts of GSK. In this regard, GSK promotes Epivir-HBV/Zeffix, a product that competes with Hepsera and Viread for the treatment of chronic HBV. Consequently, GSK's marketing strategy for Hepsera and Viread for the treatment of chronic hepatitis B may be influenced by its promotion of Epivir-HBV/Zeffix. We receive royalties from GSK equal to a percentage of GSK's net sales of Hepsera and Viread for the treatment of chronic HBV as well as net sales of GSK's Epivir-HBV/Zeffix. If GSK fails to devote sufficient resources to, or does not succeed in developing or commercializing Hepsera or Viread for the treatment of chronic HBV in its territories, our potential revenues in these territories may be substantially reduced.

In addition, Cayston and Letairis are distributed through third-party specialty pharmacies, which are pharmacies specializing in the dispensing of medications for complex or chronic conditions that may require a high level of patient education and ongoing counseling. The use of specialty pharmacies requires significant coordination with our sales and marketing, medical affairs, regulatory affairs, legal and finance organizations and involves risks, including but not limited to risks that these specialty pharmacies will:

• not provide us with accurate or timely information regarding their inventories, patient data or safety complaints;

• not effectively sell or support Cayston or Letairis;

• not devote the resources necessary to sell Cayston or Letairis in the volumes and within the time frames that we expect;

• not be able to satisfy their financial obligations to us or others; or

• cease operations.

We also rely on a third party to administer LEAP, the restricted distribution program designed to support Letairis. This third party provides information and education to prescribers and patients on the risks of Letairis, confirms insurance coverage and investigates alternative sources of reimbursement or assistance, ensures fulfillment of the risk management requirements mandated for Letairis by the FDA and coordinates and controls dispensing to patients through the third-party specialty pharmacies. Failure of this third party or the specialty pharmacies that distribute Letairis to perform as expected may result in regulatory action from the FDA or decreased Letairis sales, either of which would harm our business.

Further, Cayston may only be taken by patients using a specific inhalation device that delivers the drug to the lungs of patients. Our ongoing distribution of Cayston is entirely reliant upon the manufacturer of that device. For example, the manufacturer could encounter other issues with regulatory agencies related to the device or be unable to supply sufficient quantities of this device. In addition, the manufacturer may not be able to provide adequate warranty support for the device after it has been distributed to patients. With respect to distribution of the drug and device to patients, we are reliant on the capabilities of specialty pharmacies. For example, the distribution channel for drug and device is complicated and requires coordination. The reimbursement approval processes associated with both drug and device are similarly complex. If the device manufacturer is unable to obtain reimbursement approval or receives approval at a lower-than-expected price, sales of Cayston may be adversely affected. Any of the previously described issues may limit the sales of Cayston, which would adversely affect our financial results.

Our success will depend to a significant degree on our ability to protect our patents and other intellectual property rights both domestically and internationally. We may not be able to obtain effective patents to protect our technologies from use by competitors and patents of other companies could require us to stop using or pay for the use of required technology.

Patents and other proprietary rights are very important to our business. Our success will depend to a significant degree on our ability to:

• obtain patents and licenses to patent rights;

• preserve trade secrets;

• defend against infringement and efforts to invalidate our patents; and

• operate without infringing on the property of others.

If we have a properly drafted and enforceable patent, it can be more difficult for our competitors to use our technology to create competitive products and more difficult for our competitors to obtain a patent that prevents us from using technology we create. As part of our business strategy, we actively seek patent protection both in the United States and internationally and file additional patent applications, when appropriate, to cover improvements in our compounds, products and technology.

We have a number of U.S. and foreign patents, patent applications and rights to patents related to our compounds, products and technology, but we cannot be certain that issued patents will be enforceable or provide adequate protection or that pending patent applications will result in issued patents. Patent applications are confidential for a period of time before a patent

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is issued. As a result, we may not know if our competitors filed patent applications for technology covered by our pending applications or if we were the first to invent or first to file an application directed toward the technology that is the subject of our patent applications. Competitors may have filed patent applications or received patents and may obtain additional patents and proprietary rights that block or compete with our products. In addition, if competitors file patent applications covering our technology, we may have to participate in interference/derivation proceedings or litigation to determine the right to a patent. Litigation and interference/derivation proceedings are unpredictable and expensive, such that, even if we are ultimately successful, our results of operations may be adversely affected by such events.

From time to time, certain individuals or entities may challenge our patents. For example, in 2007, the Public Patent Foundation filed requests for re-examination with the U.S. Patent and Trademark Office (PTO) challenging four of our patents related to tenofovir disoproxil fumarate, which is an active ingredient in Stribild, Complera/Eviplera, Atripla, Truvada and Viread. The PTO granted these requests, and in 2008, the PTO confirmed the patentability of all four patents.

From time to time, we may become involved in disputes with inventors on our patents. For example, in March 2012, Jeremy Clark, a former employee of Pharmasset, which we acquired in January 2012, and inventor of U.S. Patent No. 7,429,572, filed a demand for arbitration in his lawsuit against Pharmasset and Dr. Raymond Schinazi. Mr. Clark initially filed the lawsuit against Pharmasset and Dr. Schinazi in February 2008 seeking to void the assignment provision in his employment agreement and assert ownership of U.S. Patent No. 7,429,572, which claims metabolites of sofosbuvir and RG7128. In December 2008, the court ordered a stay of the litigation pending the outcome of an arbitration proceeding required by Mr. Clark's employment agreement. Instead of proceeding with arbitration, Mr. Clark filed two additional lawsuits in September 2009 and June 2010, both of which were subsequently dismissed by the court. In September 2010, Mr. Clark filed a motion seeking reconsideration of the court's December 2008 order which was denied by the court. In December 2011, Mr. Clark filed a motion to appoint a special prosecutor. In February 2012, the court issued an order requiring Mr. Clark to enter arbitration or risk dismissal of his case. Mr. Clark filed a demand for arbitration in March 2012. The arbitration panel held a hearing in April 2013. We anticipate a decision in this case as early as June 2013. We cannot predict the outcome of the arbitration. If Mr. Clark's prior assignment of this patent to Pharmasset is voided by the arbitration panel, and he is ultimately found to be the owner of the 7,429,572 patent and it is determined that we have infringed the patent, we may be required to obtain a license from and pay royalties to Mr. Clark to commercialize sofosbuvir and RG7128.

Patents do not cover the ranolazine compound, the active ingredient of Ranexa. Instead, when it was discovered that only a sustained release formulation of ranolazine would achieve therapeutic plasma levels, patents were obtained on those formulations and the characteristic plasma levels they achieve. Patents do not cover the active ingredients in AmBisome. In addition, we do not have patent filings in China or certain other Asian countries covering all forms of adefovir dipivoxil, the active ingredient in Hepsera. Asia is a major market for therapies for HBV, the indication for which Hepsera has been developed.

We may obtain patents for certain products many years before marketing approval is obtained for those products. Because patents have a limited life, which may begin to run prior to the commercial sale of the related product, the commercial value of the patent may be limited. However, we may be able to apply for patent term extensions or supplementary protection certificates in some countries.

Generic manufacturers have sought and may continue to seek FDA approval to market generic versions of our products through an ANDA, the application form typically used by manufacturers seeking approval of a generic drug. See a description of our ANDA litigation in "Legal Proceedings" beginning on page 33 and risk factor entitled "Litigation with generic manufacturers has reduced and may continue to reduce our earnings. If we are unsuccessful in all or some of these lawsuits, some or all of our original claims in the patents may be narrowed or invalidated and generic versions of our products could be launched prior to our patent expiry." beginning on page 48.

Our success depends in large part on our ability to operate without infringing upon the patents or other proprietary rights of third parties.

If we infringe the valid patents of others, we may be prevented from commercializing products or may be required to obtain licenses from these third parties. We may not be able to obtain alternative technologies or any required license on reasonable terms or at all. If we fail to obtain these licenses or alternative technologies, we may be unable to develop or commercialize some or all of our products. For example, we are aware of a body of patents that may relate to our operation of LEAP, our restricted distribution program designed to support Letairis. We own patents that claim sofosbuvir as a chemical entity and its metabolites. However, the existence of issued patents does not guarantee our right to practice the patented technology or commercialize the patented product. Third parties may have or obtain rights to patents which they may claim could be used to prevent or attempt to prevent us from commercializing the patented product candidates obtained from the Pharmasset acquisition. For example, we are aware of patents and patent applications owned by other parties that might be alleged to cover the use of sofosbuvir. If these other parties are successful in obtaining valid and enforceable patents, and

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establishing our infringement of those patents, we could be prevented from selling sofosbuvir unless we were able to obtain a license under such patents. If any license is needed it may not be available on commercially reasonable terms or at all.

In some instances, we may be required to defend our right to a patent on an invention through an Interference proceeding before the PTO. An Interference is an administrative proceeding before the PTO designed to determine who was the first to invent the subject matter being claimed by both parties. In February 2012, we received notice that the PTO had declared an Interference between our U.S. Patent No. 7,429,572 and Idenix Pharmaceuticals, Inc.'s (Idenix) pending patent application no. 12/131868. Our patent covers metabolites of sofosbuvir and RG7128. Idenix is attempting to claim a class of compounds, including these metabolites, in their pending patent application. In the course of this proceeding, both parties will be called upon to submit evidence of the date they conceived of their respective inventions. The Interference will determine who was first to invent these compounds and therefore who is entitled to the patent claiming these compounds. In March 2013, the PTO Patent Trials and Appeal Board (the Board) determined that Idenix is not entitled to the benefit of any of their early application filing dates because none of those patent applications taught how to make the compounds in dispute. The Board also determined that we are entitled to the filing date of its earliest application. As a result, the Board determined that we were first to file its patent application on the compounds in dispute and is therefore the “senior party” in the interference. In the second phase of the interference, the Board will determine who was first to invent the compounds. The party who is deemed first to invent will prevail in the interference proceeding. Idenix bears the burden of establishing that despite their much later patent application filing date, they were nevertheless first to invent the compounds in dispute. In order to prove they were first to invent, Idenix must prove that they were first to conceive of a compound within the scope of those in dispute, namely that (1) the named inventors had identified the structure, a method of making and a use for a disputed compound and (2) that Idenix worked diligently from their earliest conception date until they made and tested the compound or filed their last application in 2008.

If the Board determines that Idenix was first to invent and is entitled to these patent claims and it is determined that we have infringed those claims, we may be required to obtain a license from and pay royalties to Idenix to commercialize sofosbuvir and RG7128. Any determination by the Board can be appealed by either party to U.S. Federal Court.

We believe the Idenix application involved in the Interference and similar U.S. and foreign patents claiming the same compounds and metabolites are invalid. As a result, we filed an Impeachment Action in Canadian Federal Court to invalidate the Idenix CA2490191 patent, which is the Canadian patent that corresponds to the Idenix U.S. Patent No. 7608600 and the Idenix patent application that is the subject of the Interference. Idenix has now asserted that our Canadian Patent No. 2527657, corresponding to the '572 patent in the Interference, is invalid. We filed a similar legal action in the Federal Court of Norway seeking to invalidate Idenix's corresponding Norwegian patent. We filed a similar legal action in the Federal Court of Australia seeking to invalidate the corresponding Australian patent. We may bring similar action in other countries in 2013. Idenix has not been awarded patents on these compounds in European countries, Japan or China. In the event such patents issue, we expect to challenge them in proceedings similar to those we invoked in Canada, Norway and Australia.

Furthermore, we use significant proprietary technology and rely on unpatented trade secrets and proprietary know-how to protect certain aspects of our production and other technologies. Our trade secrets may become known or independently discovered by our competitors.

Manufacturing problems, including at our third-party manufacturers and corporate partners, could cause inventory shortages and delay product shipments and regulatory approvals, which may adversely affect our results of operations.

In order to generate revenue from our products, we must be able to produce sufficient quantities of our products to satisfy demand. Many of our products are the result of complex manufacturing processes. The manufacturing process for pharmaceutical products is also highly regulated and regulators may shut down manufacturing facilities that they believe do not comply with regulations.

Our products are either manufactured at our own facilities or by third-party manufacturers or corporate partners. We depend on third parties to perform manufacturing activities effectively and on a timely basis for the majority of our solid dose products. In addition, Roche, either by itself or through third parties, is responsible for manufacturing Tamiflu. We, our third-party manufacturers and our corporate partners are subject to current Good Manufacturing Practices (GMP), which are extensive regulations governing manufacturing processes, stability testing, record keeping and quality standards as defined by the FDA and the EMA. Similar regulations are in effect in other countries.

Our third-party manufacturers and corporate partners are independent entities who are subject to their own unique operational and financial risks which are out of our control. If we or any of these third-party manufacturers or corporate partners fail to perform as required, this could impair our ability to deliver our products on a timely basis or receive royalties or cause delays in our clinical trials and applications for regulatory approval. To the extent these risks materialize and affect their performance obligations to us, our financial results may be adversely affected.

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In addition, we, our third-party manufacturers and our corporate partners may only be able to produce some of our products at one or a limited number of facilities and, therefore, have limited manufacturing capacity for certain products. For example, in 2012, due to unexpected delays both in qualifying two new external sites and with expanding Cayston manufacturing in San Dimas, we were unable to supply enough Cayston to fulfill our projected demand. From February through September 2012, we suspended access for patients with new prescriptions for Cayston, subject to certain exceptions where specific medical need exists. As a result of our inability to manufacture sufficient Cayston to meet demand, the amount of revenues we received from the sale of Cayston was reduced.

Our manufacturing operations are subject to routine inspections by regulatory agencies. For example, in April 2013, the FDA conducted an inspection of our Foster City facility and issued 483 Inspectional Observations, which noted deficiencies in documentation and validation of certain quality testing procedures and methods. As a result of the observations, the FDA delivered Complete Response Letters notifying us that it was unable to approve our NDAs for elvitegravir and cobicistat as standalone agents. There is a risk that we may be unable to remedy the deficiencies cited by the FDA in the Complete Response Letters on a timely basis and that our inability to address those deficiencies could adversely impact currently marketed products and products in development which could adversely impact our anticipated revenues and stock price. Further, there is risk that regulatory agencies in other countries where marketing applications are pending will undertake similar additional reviews or apply a heightened standard of review, which could delay the approval of such products in those countries.

Our ability to successfully manufacture and commercialize Cayston will depend upon our ability to manufacture in a multi-product facility.

Aztreonam, the active pharmaceutical ingredient in Cayston, is a mono-bactam Gram-negative antibiotic. We manufacture Cayston by ourselves in San Dimas, California, or through third parties, in multi-product manufacturing facilities. Historically, the FDA has permitted the manufacture of mono-bactams in multi-product manufacturing facilities; however, there can be no assurance that the FDA will continue to allow this practice. We do not currently have a single-product facility that can be dedicated to the manufacture of Cayston nor have we engaged a contract manufacturer with a single-product facility for Cayston. If the FDA prohibits the manufacture of mono-bactam antibiotics, like aztreonam, in multi-product manufacturing facilities in the future, we may not be able to procure a single-product manufacturing facility in a timely manner, which would adversely affect our commercial supplies of Cayston and our anticipated financial results attributable to such product.

We may not be able to obtain materials or supplies necessary to conduct clinical trials or to manufacture and sell our products, which would limit our ability to generate revenues.

We need access to certain supplies and products to conduct our clinical trials and to manufacture our products. In light of the global economic downturn, we have had increased difficulty in purchasing certain of the raw materials used in our manufacturing process. If we are unable to purchase sufficient quantities of these materials or find suitable alternate materials in a timely manner, our development efforts for our product candidates may be delayed or our ability to manufacture our products would be limited, which would limit our ability to generate revenues.

Suppliers of key components and materials must be named in an NDA filed with the FDA, EMA or other regulatory authority for any product candidate for which we are seeking marketing approval, and significant delays can occur if the qualification of a new supplier is required. Even after a manufacturer is qualified by the regulatory authority, the manufacturer must continue to expend time, money and effort in the area of production and quality control to ensure full compliance with GMP. Manufacturers are subject to regular, periodic inspections by the regulatory authorities following initial approval. If, as a result of these inspections, a regulatory authority determines that the equipment, facilities, laboratories or processes do not comply with applicable regulations and conditions of product approval, the regulatory authority may suspend the manufacturing operations. If the manufacturing operations of any of the single suppliers for our products are suspended, we may be unable to generate sufficient quantities of commercial or clinical supplies of product to meet market demand, which would in turn decrease our revenues and harm our business. In addition, if delivery of material from our suppliers were interrupted for any reason, we may be unable to ship certain of our products for commercial supply or to supply our products in development for clinical trials. In addition, some of our products and the materials that we utilize in our operations are made at only one facility. For example, we manufacture AmBisome exclusively at our facilities in San Dimas, California. In the event of a disaster, including an earthquake, equipment failure or other difficulty, we may be unable to replace this manufacturing capacity in a timely manner and may be unable to manufacture AmBisome to meet market needs.

Cayston is dependent on two different third-party single-source suppliers. First, aztreonam, the active pharmaceutical ingredient in Cayston, is manufactured by a single supplier at a single site. Second, it is administered to the lungs of patients through a device that is made by a single supplier at a single site. Disruptions or delays with any of these single suppliers could adversely affect our ability to supply Cayston, and we cannot be sure that alternative suppliers can be identified in a timely manner, or at all. See the Risk Factor entitled “Our ability to successfully manufacture and commercialize Cayston will depend upon our ability to manufacture in a multi-product facility.”

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In addition, we depend on a single supplier for high-quality cholesterol, which is used in the manufacture of AmBisome. We also rely on a single source for the active pharmaceutical ingredient of Hepsera, Letairis and Vistide and for the tableting of Letairis. Astellas US LLC, which markets Lexiscan in the United States, is responsible for the commercial manufacture and supply of product in the United States and is dependent on a single supplier for the active pharmaceutical ingredient of Lexiscan. Problems with any of the single suppliers we depend on may negatively impact our development and commercialization efforts.

A significant portion of the raw materials and intermediates used to manufacture our HIV products (Stribild, Complera/Eviplera, Atripla, Truvada, Viread and Emtriva) are supplied by Chinese-based companies. As a result, an international trade dispute between China and the United States or any other actions by the Chinese government that would limit or prevent Chinese companies from supplying these materials would adversely affect our ability to manufacture and supply our HIV products to meet market needs and have a material and adverse effect on our operating results.

Litigation with generic manufacturers has reduced and may continue to reduce our earnings. If we are unsuccessful in all or some of these lawsuits, some or all of our original claims in the patents may be narrowed or invalidated and generic versions of our products could be launched prior to our patent expiry.

As part of the approval process of some of our products, the FDA granted a New Chemical Entity (NCE) exclusivity period during which other manufacturers' applications for approval of generic versions of our product will not be granted. Generic manufacturers may challenge the patents protecting products that have been granted exclusivity one year prior to the end of the exclusivity period. Generic manufacturers have sought and may continue to seek FDA approval for a similar or identical drug through an ANDA, the application form typically used by manufacturers seeking approval of a generic drug.

We received notices that generic manufacturers have submitted ANDAs to manufacture a generic version of Atripla, Truvada, Viread, Hepsera, Ranexa and Tamiflu in the United States and Atripla, Truvada and Viread in Canada. We expect to begin trial with some of the generic manufacturers in 2013. In February 2013, Gilead and Teva reached an agreement in principle to settle the ongoing patent litigation concerning the four patents that protect tenofovir disoproxil fumarate in our Viread, Truvada and Atripla products. Under the agreement, Teva will be allowed to launch a generic version of Viread on December 15, 2017. The settlement agreement was recently filed with the Federal Trade Commission (FTC) and Department of Justice (DOJ) and will be final after 45 days, if the FTC and DOJ do not object. As a result of the recent invalidation of the patents protecting entecavir and due to declining sales of Hepsera in the United States, in March 2013, we granted Sigmapharm Labs (Sigmapharm) a Covenant Not to Sue if it launches a generic version of Hepsera prior to the expiration of our patents and then filed a motion to dismiss all claims in the lawsuit. Once Sigmapharm obtains FDA approval of its product, it may launch its generic product. The trial related to ten of the patents associated with Ranexa is scheduled to begin in April 2013. This trial related to three of the patents associated with Truvada in Canada is currently scheduled for hearing in September 2013. The trial related to the two patents protecting emtricitabine patent in Atripla is scheduled to begin in October 2013.

We cannot predict the ultimate outcome of these actions, and we may spend significant resources enforcing and defending these patents. If we are unsuccessful in these lawsuits, some or all of our original claims in the patents may be narrowed or invalidated and the patent protection for Atripla, Truvada, Viread Ranexa and Tamiflu in the United States and Atripla, Truvada and Viread in Canada could be substantially shortened. Further, if all of the patents covering one or more products are invalidated, the FDA or Canadian Ministry of Health could approve the requests to manufacture a generic version of such products in the United States or Canada, respectively, prior to the expiration date of those patents. The sale of generic versions of these products earlier than their patent expiration would have a significant negative effect on our revenues and results of operations.

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We face credit risks from our Southern European customers that may adversely affect our results of operations.

Our European product sales to government-owned or supported customers in Southern Europe, specifically Greece, Italy, Portugal and Spain have historically been and continue to be subject to significant payment delays due to government funding and reimbursement practices. This has resulted and may continue to result in days sales outstanding being significantly higher in these countries due to the average length of time that accounts receivable remain outstanding. As of March 31, 2013, our accounts receivable in these countries totaled approximately $849.6 million of which, $348.5 million were past due greater than 120 days and $114.1 million were past due greater than 365 days as follows (in thousands):

	March 31, 2013
	Greater than 120 days past due		Greater than 365 days past due
Italy	$	99,239	$	37,303
Spain	141,460		7,938
Portugal	74,654		62,934
Greece	33,178		5,957
Total	$	348,531	$	114,132

Historically, receivable balances with certain publicly-owned hospitals accumulate over a period of time and are then subsequently settled as large lump sum payments. This pattern is also experienced by other pharmaceutical companies that sell directly to hospitals. If significant changes were to occur in the reimbursement practices of these European governments or if government funding becomes unavailable, we may not be able to collect on amounts due to us from these customers and our results of operations would be adversely affected.

In 2012, we collected $533.4 million in past due accounts receivable from customers based in Spain and Portugal. This included $349.7 million in proceeds from a one-time factoring arrangement where we sold receivables in Spain.

In 2011, the Greek government settled substantially all of its outstanding receivables subject to the bond settlement with zero-coupon bonds that trade at a discount to face value. In March 2012, the Greek government restructured its sovereign debt which impacted all holders of Greek bonds. As a result, we recorded a $40.1 million loss.

Our revenues and gross margin could be reduced by imports from countries where our products are available at lower prices.

Prices for our products are based on local market economics and competition and sometimes differ from country to country. Our sales in countries with relatively higher prices may be reduced if products can be imported into those or other countries from lower price markets. There have been cases in which other pharmaceutical products were sold at steeply discounted prices in the developing world and then re-exported to European countries where they could be re-sold at much higher prices. If this happens with our products, particularly Truvada and Viread, which we have agreed to make available at substantially reduced prices to 134 countries participating in our Gilead Access Program, or Atripla, which Merck distributes at substantially reduced prices to HIV infected patients in developing countries under our 2006 agreement, our revenues would be adversely affected. In addition, we have established partnerships with thirteen Indian generic manufacturers to distribute high-quality, low-cost generic versions of tenofovir disoproxil fumarate to 112 developing world countries, including India. If generic versions of our medications under these licenses are then re-exported to the United States, Europe or other markets outside of these 112 countries, our revenues would be adversely affected.

In addition, purchases of our products in countries where our selling prices are relatively low for resale in countries in which our selling prices are relatively high may adversely impact our revenues and gross margin and may cause our sales to fluctuate from quarter to quarter. For example, in the European Union, we are required to permit products purchased in one country to be sold in another country. Purchases of our products in countries where our selling prices are relatively low for resale in countries in which our selling prices are relatively high affect the inventory level held by our wholesalers and can cause the relative sales levels in the various countries to fluctuate from quarter to quarter and not reflect the actual consumer demand in any given quarter. These quarterly fluctuations may impact our earnings, which could adversely affect our stock price and harm our business.

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Expensive litigation and government investigations have reduced and may continue to reduce our earnings.

We are involved in a number of litigation, investigation and other dispute-related matters that require us to expend substantial internal and financial resources. We expect these matters will continue to require a high level of internal and financial resources for the foreseeable future. These matters have reduced and will continue to reduce our earnings. Please see a description of our Department of Justice investigation; Interference and litigation proceedings with Idenix, arbitration with Roche and contract arbitration with Jeremy Clark in "Legal Proceedings" beginning on page 33. The outcome of the lawsuits above, or any other lawsuits that may be brought against us, the investigation or any other investigations that may be initiated, are inherently uncertain, and adverse developments or outcomes can result in significant expenses, monetary damages, penalties or injunctive relief against us that could significantly reduce our earnings and cash flows and harm our business.

In some countries, we may be required to grant compulsory licenses for our products or face generic competition for our products.

In a number of developing countries, government officials and other interested groups have suggested that pharmaceutical companies should make drugs for HIV infection available at low cost. Alternatively, governments in those developing countries could require that we grant compulsory licenses to allow competitors to manufacture and sell their own versions of our products, thereby reducing our product sales. For example, in the past, certain offices of the government of Brazil have expressed concern over the affordability of our HIV products and declared that they were considering issuing compulsory licenses to permit the manufacture of otherwise patented products for HIV infection, including Viread. In July 2009, the Brazilian patent authority rejected our patent application for tenofovir disoproxil fumarate, the active pharmaceutical ingredient in Viread. This was the highest level of appeal available to us within the Brazilian patent authority. Because we do not currently have a patent in Brazil, the Brazilian government now purchases its supply of tenofovir disoproxil fumarate from generic manufacturers. In addition, concerns over the cost and availability of Tamiflu related to a potential avian flu pandemic and H1N1 influenza generated international discussions over compulsory licensing of our Tamiflu patents. For example, the Canadian government considered allowing Canadian manufacturers to manufacture and export the active ingredient in Tamiflu to eligible developing and least developed countries under Canada's Access to Medicines Regime. Furthermore, Roche issued voluntary licenses to permit third-party manufacturing of Tamiflu. For example, Roche granted a sublicense to Shanghai Pharmaceutical (Group) Co., Ltd. for China and a sublicense to India's Hetero Drugs Limited for India and certain developing countries. Should one or more compulsory licenses be issued permitting generic manufacturing to override our Tamiflu patents, or should Roche issue additional voluntary licenses to permit third-party manufacturing of Tamiflu, those developments could reduce royalties we receive from Roche's sales of Tamiflu. Certain countries do not permit enforcement of our patents, and third-party manufacturers are able to sell generic versions of our products in those countries. Compulsory licenses or sales of generic versions of our products could significantly reduce our sales and adversely affect our results of operations, particularly if generic versions of our products are imported into territories where we have existing commercial sales.

Changes in royalty revenue disproportionately affect our pre-tax income, earnings per share and gross margins.

A portion of our revenues is derived from royalty revenues recognized from collaboration agreements with third parties. Royalty revenues impact our pre-tax income, earnings per share and gross margins disproportionately more than their contributions to our revenues. Any increase or decrease to our royalty revenue could be material and could significantly impact our operating results. For example, Roche's Tamiflu sales have unpredictable variability due to their strong relationship with seasonal influenza and global pandemic planning efforts. Tamiflu royalties increased sharply in 2009 and the first quarter of 2010 primarily as a result of pandemic planning initiatives worldwide. Tamiflu royalties since the second quarter of 2010 have decreased due to declining pandemic planning initiatives worldwide. During periods when our royalty revenue from Tamiflu increase, we will see a disproportionate increase in our pre-tax income, earnings per share and gross margins. Similarly, during periods when our royalty from Tamiflu decrease, we will see a disproportionate decrease in our pre-tax income, earnings per share and gross margins.

We may face significant liability resulting from our products that may not be covered by insurance and successful claims could materially reduce our earnings.

The testing, manufacturing, marketing and use of our commercial products, as well as product candidates in development, involve substantial risk of product liability claims. These claims may be made directly by consumers, healthcare providers, pharmaceutical companies or others. In recent years, coverage and availability of cost-effective product liability insurance has decreased, so we may be unable to maintain sufficient coverage for product liabilities that may arise. In addition, the cost to defend lawsuits or pay damages for product liability claims may exceed our coverage. If we are unable to maintain adequate coverage or if claims exceed our coverage, our financial condition and our ability to clinically test our product candidates and market our products will be adversely impacted. In addition, negative publicity associated with any claims, regardless of their merit, may decrease the future demand for our products and impair our financial condition.

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Business disruptions from natural or man-made disasters may harm our future revenues.

Our worldwide operations could be subject to business interruptions stemming from natural or man-made disasters for which we may be self-insured. Our corporate headquarters and Fremont locations, which together house a majority of our R&D activities, and our San Dimas and Oceanside manufacturing facilities are located in California, a seismically active region. As we do not carry earthquake insurance and significant recovery time could be required to resume operations, our financial condition and operating results could be materially adversely affected in the event of a major earthquake.

Changes in our effective income tax rate could reduce our earnings.

Various factors may have favorable or unfavorable effects on our income tax rate. These factors include, but are not limited to, interpretations of existing tax laws, changes in tax laws and rates, our portion of the non-deductible pharmaceutical excise tax, the accounting for stock options and other share-based payments, mergers and acquisitions, the amortization of certain acquisition related intangibles for which we receive no tax benefit, future levels of R&D spending, changes in accounting standards, changes in the mix of earnings in the various tax jurisdictions in which we operate, changes in overall levels of pre-tax earnings and resolution of federal, state and foreign income tax audits. The impact on our income tax provision resulting from the above mentioned factors may be significant and could have a negative impact on our net income.

Our income tax returns are audited by federal, state and foreign tax authorities. We are currently under examination by the Internal Revenue Service for the 2008 and 2009 tax years and by various state and foreign jurisdictions. There are differing interpretations of tax laws and regulations, and as a result, significant disputes may arise with these tax authorities involving issues of the timing and amount of deductions and allocations of income among various tax jurisdictions. Resolution of one or more of these exposures in any reporting period could have a material impact on the results of operations for that period.

If we fail to attract and retain highly qualified personnel, we may be unable to successfully develop new product candidates, conduct our clinical trials and commercialize our product candidates.

Our future success will depend in large part on our continued ability to attract and retain highly qualified scientific, technical and management personnel, as well as personnel with expertise in clinical testing, governmental regulation and commercialization. We face competition for personnel from other companies, universities, public and private research institutions, government entities and other organizations. Competition for qualified personnel in the biopharmaceutical field is intense, and there is a limited pool of qualified potential employees to recruit. We may not be able to attract and retain quality personnel on acceptable terms. If we are unsuccessful in our recruitment and retention efforts, our business may be harmed.

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ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

Issuer Purchases of Equity Securities

During the first quarter of 2013, we made $82.2 million in purchases under our January 2011, three-year, $5.00 billion stock repurchase program. As of March 31, 2013, we had repurchased $1.15 billion of our common stock under the January 2011 stock repurchase program with a remaining authorized amount of $3.85 billion available for repurchases under this program. We have suspended our share repurchases in order to focus on debt repayment during the first half of 2013.

The table below summarizes our stock repurchase activity for the three months ended March 31, 2013 (in thousands, except per share amounts):

	Total Number of Shares Purchased		Average Price Paid per Share		Total Number of Shares Purchased as Part of Publicly Announced Program	(1)	Maximum Fair Value of Shares that May Yet Be Purchased Under the Program		(1)
January 1 – January 31, 2013	1,843		$	38.84	1,785		$	3,860,776
February 1 – February 28, 2013	1,291		$	40.75	321		$	3,847,868
March 1 – March 31, 2013	199		$	45.87	—		$	3,847,868
Total	3,333	(2)	$	40.00	2,106	(2)

⁽¹⁾  In January 2011, we announced that our Board authorized a $5.00 billion stock repurchase program, which expires in January 2014.

⁽²⁾  The difference between the total number of shares purchased and the total number of shares purchased as part of publicly announced programs is due to the equivalent value in shares of common stock withheld by us from employee restricted stock awards in order to satisfy our applicable tax withholding obligations.

ITEM 3. DEFAULTS UPON SENIOR SECURITIES

Not applicable.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

ITEM 5. OTHER INFORMATION

Not applicable.

52

ITEM 6.    Exhibit Index

Exhibit Footnote		Exhibit Number	Description of Document
√(1)	2.1		Agreement and Plan of Merger among Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc., dated as of March 12, 2009
†(2)	2.5		Agreement and Plan of Merger among Registrant, Merger Sub and Pharmasset, Inc., dated as of November 21, 2011
(3)	3.1		Amended and Restated Certificate of Incorporation of Registrant, as amended and restated on May 8, 2013
(4)	3.2		Amended and Restated Bylaws of Registrant, as amended and restated on May 12, 2011
	4.1		Reference is made to Exhibit 3.1 and Exhibit 3.2
(5)	4.2		Indenture related to the Convertible Senior Notes due 2013 (2013 Notes), between Registrant and Wells Fargo Bank, National Association, as trustee (including form of 0.625% Convertible Senior Note due 2013), dated April 25, 2006
(6)	4.3		Indenture related to the Convertible Senior Notes due 2014 (2014 Notes), between Registrant and Wells Fargo Bank, National Association, as trustee (including form of 1.00% Convertible Senior Note due 2014), dated July 30, 2010
(6)	4.4		Indenture related to the Convertible Senior Notes due 2016 (2016 Notes), between Registrant and Wells Fargo Bank, National Association, as trustee (including form of 1.625% Convertible Senior Note due 2016), dated July 30, 2010
(7)	4.5		Indenture related to Senior Notes, dated as of March 30, 2011, between Registrant and Wells Fargo, National Association, as Trustee
(7)	4.6		First Supplemental Indenture related to Senior Notes, dated as of March 30, 2011, between Registrant and Wells Fargo, National Association, as Trustee (including form of Senior Notes)
(8)	4.7		Second Supplemental Indenture related to Senior Notes, dated as of December 13, 2011, between Registrant and Wells Fargo, National Association, as Trustee (including Form of 2014 Note, Form of 2016 Note, Form of 2021 Note, Form of 2041 Note)
(9)	10.1		Confirmation of OTC Convertible Note Hedge related to 2013 Notes, dated April 19, 2006, as amended and restated as of April 24, 2006, between Registrant and Bank of America, N.A.
(9)	10.2		Confirmation of OTC Warrant Transaction, dated April 19, 2006, as amended and restated as of April 24, 2006, between Registrant and Bank of America, N.A. for warrants expiring in 2013
(10)	10.3		Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated July 26, 2010, between Registrant and Goldman, Sachs & Co.
(10)	10.4		Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association
(10)	10.5		Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated July 26, 2010, between Registrant and Goldman, Sachs & Co.
(10)	10.6		Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association
(10)	10.7		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2014
(10)	10.8		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2014
(10)	10.9		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2016
(10)	10.10		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2016

53

Exhibit Footnote		Exhibit Number	Description of Document
(11)	10.11		Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 5, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.12		Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.13		Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 5, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.14		Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.15		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2014
(11)	10.16		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2014
(11)	10.17		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2016
(11)	10.18		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2016
(11)	10.19		Amendment to Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.20		Amendment to Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.21		Amendment to Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.22		Amendment to Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.23		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.24		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.25		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.26		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(12)	10.27		5-Year Revolving Credit Facility Credit Agreement among Registrant and Gilead Biopharmaceutics Ireland Corporation, as Borrowers, Bank of America, N.A., as Administrative Agent, Swing Line Lender and L/C Issuer, certain other lenders parties thereto, Barclays Capital, as Syndication Agent, and Goldman Sachs Bank USA, JPMorgan Chase Bank, N.A., Royal Bank of Canada and Wells Fargo Bank, N.A., as Co-Documentation Agents, dated as of January 12, 2012
(12)	10.28		Parent Guaranty Agreement (5-Year Revolving Credit Facility), dated as of January 12, 2012, by Registrant
*(13)	10.29		Gilead Sciences, Inc. 1991 Stock Option Plan, as amended through January 29, 2003
*(14)	10.30		Form of option agreements used under the 1991 Stock Option Plan
*(13)	10.31		Gilead Sciences, Inc. 1995 Non-Employee Directors' Stock Option Plan, as amended through January 30, 2002

54

Exhibit Footnote		Exhibit Number	Description of Document
*(14)	10.32		Form of option agreement used under the Gilead Sciences, Inc. 1995 Non-Employee Directors' Stock Option Plan
*(16)	10.33		Gilead Sciences, Inc. 2004 Equity Incentive Plan, as amended through May 6, 2009
*(17)	10.34		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants prior to February 2008)
*(18)	10.35		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants made February 2008 through April 2009)
*(19)	10.36		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants commencing in May 2009)
*(20)	10.37		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants commencing in February 2010)
*(21)	10.38		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for 2011 and subsequent year grants)
*(18)	10.39		Form of non-employee director stock option agreement used under 2004 Equity Incentive Plan (for grants prior to 2008)
*(18)	10.40		Form of non-employee director option agreement used under 2004 Equity Incentive Plan (for initial grants made in 2008)
*(18)	10.41		Form of non-employee director option agreement used under 2004 Equity Incentive Plan (for annual grants made in May 2008)
*(19)	10.42		Form of non-employee director option agreement used under 2004 Equity Incentive Plan (for annual grants commencing in May 2009)
*(22)	10.43		Form of restricted stock unit issuance agreement used under 2004 Equity Incentive Plan (for annual grants to non-employee directors commencing in May 2012)
*(19)	10.44		Form of restricted stock award agreement used under 2004 Equity Incentive Plan (for annual grants to certain non-employee directors prior to May 2012)
*(19)	10.45		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2009)
*(20)	10.46		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2010)
*(21)	10.47		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2011)
*(23)	10.48		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2012)
*	10.49		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for TSR Goals in 2013)
*	10.50		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for Revenue Goals in 2013)
*(24)	10.51		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made prior to May 2009)
*(19)	10.52		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers commencing in May 2009)
*(25)	10.53		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (service-based vesting for certain executive officers commencing in November 2009)

55

Exhibit Footnote		Exhibit Number	Description of Document
*(21)	10.54		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (service-based vesting for certain executive officers commencing in 2011)
*(20)	10.55		Gilead Sciences, Inc. Employee Stock Purchase Plan, amended and restated on November 3, 2009
*(26)	10.56		Gilead Sciences, Inc. International Employee Stock Purchase Plan, adopted November 3, 2009
*(27)	10.57		Gilead Sciences, Inc. Deferred Compensation Plan-Basic Plan Document
*(27)	10.58		Gilead Sciences, Inc. Deferred Compensation Plan-Adoption Agreement
*(27)	10.59		Addendum to the Gilead Sciences, Inc. Deferred Compensation Plan
*(28)	10.60		Gilead Sciences, Inc. 2005 Deferred Compensation Plan, as amended and restated on October 23, 2008
*(23)	10.61		Gilead Sciences, Inc. Severance Plan, as amended on January 26, 2012
*(17)	10.62		Gilead Sciences, Inc. Corporate Bonus Plan
*(4)	10.63		Amended and Restated Gilead Sciences, Inc. Code Section 162(m) Bonus Plan
*(29)	10.64		2013 Base Salaries for the Named Executive Officers
*(30)	10.65		Offer Letter dated April 16, 2008 between Registrant and Robin Washington
*(14)	10.66		Form of Indemnity Agreement entered into between Registrant and its directors and executive officers
*(14)	10.67		Form of Employee Proprietary Information and Invention Agreement entered into between Registrant and certain of its officers and key employees
*(20)	10.68		Form of Employee Proprietary Information and Invention Agreement entered into between Registrant and certain of its officers and key employees (revised in September 2006)
(31)	10.69		Amended and Restated Collaboration Agreement by and among Registrant, Gilead Holdings, LLC, Bristol-Myers Squibb Company, E.R. Squibb & Sons, L.L.C., and Bristol-Myers Squibb & Gilead Sciences, LLC, dated September 28, 2006
(18)	10.70		Commercialization Agreement by and between Gilead Sciences Limited and Bristol-Myers Squibb Company, dated December 10, 2007
(32)	10.71		Amendment Agreement, dated October 25, 1993, between Registrant, the Institute of Organic Chemistry and Biochemistry (IOCB) and Rega Stichting v.z.w. (REGA), together with the following exhibits: the License Agreement, dated December 15, 1991, between Registrant, IOCB and REGA (the 1991 License Agreement), the License Agreement, dated October 15, 1992, between Registrant, IOCB and REGA (the October 1992 License Agreement) and the License Agreement, dated December 1, 1992, between Registrant, IOCB and REGA (the December 1992 License Agreement)
(33)	10.72		Amendment Agreement between Registrant and IOCB/REGA, dated December 27, 2000 amending the 1991 License Agreement and the December 1992 License Agreement
(31)	10.73		Sixth Amendment Agreement to the License Agreement, between IOCB/REGA and Registrant, dated August 18, 2006 amending the October 1992 License Agreement and the December 1992 License Agreement
(31)	10.74		Development and License Agreement among Registrant and F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc., dated September 27, 1996
(34)	10.75		First Amendment and Supplement dated November 15, 2005 to the Development and Licensing Agreement between Registrant, F. Hoffmann-La Roche Ltd and Hoffman-La Roche Inc. dated September 27, 1996

56

Exhibit Footnote		Exhibit Number	Description of Document
(35)	10.76		Second Amendment dated December 22, 2011 to the Development and Licensing Agreement between Registrant, F. Hoffmann-La Roche Ltd and Hoffman-La Roche Inc. dated September 27, 1996
+ (36)	10.77		Third Amendment dated October 5, 2012 to the Development and Licensing Agreement between Registrant, F. Hoffmann-La Roche Ltd and Hoffman-La Roche Inc. dated September 27, 1996
(37)	10.78		Exclusive License Agreement between Registrant (as successor to Triangle Pharmaceuticals, Inc.), Glaxo Group Limited, The Wellcome Foundation Limited, Glaxo Wellcome Inc. and Emory University, dated May 6, 1999
(38)	10.79		Royalty Sale Agreement by and among Registrant, Emory University and Investors Trust & Custodial Services (Ireland) Limited, solely in its capacity as Trustee of Royalty Pharma, dated July 18, 2005
(38)	10.80		Amended and Restated License Agreement between Registrant, Emory University and Investors Trust & Custodial Services (Ireland) Limited, solely in its capacity as Trustee of Royalty Pharma, dated July 21, 2005
(39)	10.81		License Agreement between Japan Tobacco Inc. and Registrant, dated March 22, 2005
(40)	10.82		First Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated May 19, 2005
(40)	10.83		Second Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated May 17, 2010
(40)	10.84		Third Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated July 5, 2011
(40)	10.85		Fourth Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated July 5, 2011
(41)	10.86		License Agreement between Registrant (as successor to Myogen, Inc.) and Abbott Deutschland Holding GmbH dated October 8, 2001
+(42)	10.87		License Agreement between Registrant (as successor to Myogen, Inc.) and Glaxo Group Limited, dated March 3, 2006
(41)	10.88		License Agreement between Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated March 27, 1996
(43)	10.89		First Amendment to License Agreement between Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated July 3, 1997
(43)	10.90		Amendment No. 2 to License Agreement between Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated November 30. 1999
(44)	10.91		Amendment No. 4 to License Agreement with Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated June 20, 2006
(35)	10.92		Amendment No. 5 to License Agreement with Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated December 22, 2011
(45)	10.93		License and Collaboration Agreement by and among Registrant, Gilead Sciences Limited and Janssen R&D Ireland (formerly Tibotec Pharmaceuticals), dated July 16, 2009
(40)	10.94		Second Amendment to License and Collaboration Agreement by and among Registrant, Gilead Sciences Limited and Janssen R&D Ireland (formerly Tibotec Pharmaceuticals), dated July 1, 2011

57

Exhibit Footnote		Exhibit Number	Description of Document
+	10.95		Amended and Restated Second Amendment to License and Collaboration Agreement by and among Registrant, Gilead Sciences Limited and Janssen R&D Ireland (formerly Tibotec Pharmaceuticals), dated February 7, 2013
(46)	10.96		Master Clinical and Commercial Supply Agreement between Gilead World Markets, Limited, Registrant and Patheon Inc., dated January 1, 2003
(38)	10.97		Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama), Ltd., dated July 17, 2003
(47)	10.98		Addendum to Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama) Ltd., dated May 10, 2007
(28)	10.99		Addendum to Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama) Ltd., dated December 5, 2008
(21)	10.100		Addendum to Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama) Ltd., dated February 3. 2011
(34)	10.101		Restated and Amended Toll Manufacturing Agreement between Gilead Sciences Limited, Registrant and Nycomed GmbH (formerly ALTANA Pharma Oranienburg GmbH), dated November 7, 2005
+(9)	10.102		Emtricitabine Manufacturing Supply Agreement between Gilead Sciences Limited and Evonik Degussa GmbH (formerly known as Degussa AG), dated June 6, 2006
+(10)	10.103		Amendment No. 1 to Emtricitabine Manufacturing Supply Agreement between Gilead Sciences Limited and Evonik Degussa GmbH (formerly known as Degussa AG), dated April 30, 2010
(48)	10.104		Purchase and Sale Agreement and Joint Escrow Instructions between Electronics for Imaging, Inc. and Registrant, dated July 18, 2012
(59)	10.105		Amendment No. 1, dated October 30, 2012, to the Purchase and Sale Agreement and Joint Escrow Instructions between Electronics for Imaging, Inc. and Registrant, dated July 18, 2012
	31.1		Certification of Chief Executive Officer, as required by Rule 13a-14(a) or Rule 15d-14(a) of the Securities Exchange Act of 1934, as amended
	31.2		Certification of Chief Financial Officer, as required by Rule 13a-14(a) or Rule 15d-14(a) of the Securities Exchange Act of 1934, as amended
	32.1**		Certifications of Chief Executive Officer and Chief Financial Officer, as required by Rule 13a-14(b) or Rule 15d-14(b) and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. §1350)
	101***		The following materials from Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2013, formatted in Extensible Business Reporting Language (XBRL) includes: (i) Consolidated Balance Sheets, (ii) Consolidated Statements of Income, (iii) Consolidated Statements of Comprehensive Income, (iv) Consolidated Statements of Cash Flows and (v) Notes to Consolidated Financial Statements.

(1) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on March 12, 2009, and incorporated herein by reference.

(2) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on November 25, 2011, and incorporated herein by reference.

(3) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on May 8, 2013, and incorporated herein by reference.

(4) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on May 17, 2011, and incorporated herein by reference.

58

(5) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on April 25, 2006, and incorporated herein by reference.

(6) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on August 2, 2010, and incorporated herein by reference.

(7) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on April 1, 2011, and incorporated herein by reference.

(8) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on December 13, 2011, and incorporated herein by reference.

(9) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2006, and incorporated herein by reference.

(10) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2010, and incorporated herein by reference.

(11) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2010, and incorporated herein by reference.

(12) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on January 17, 2012, and incorporated herein by reference.

(13) Filed as an exhibit to Registrant's Registration Statement on Form S-8 (No. 333-102912) filed on January 31, 2003, and incorporated herein by reference.

(14) Filed as an exhibit to Registrant's Registration Statement on Form S-1 (No. 33-55680), as amended, and incorporated herein by reference.

(15) Filed as an exhibit to Registrant's Annual Report on Form 10-K/A for the fiscal year ended December 31, 1998, and incorporated herein by reference.

(16) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on May 11, 2009, and incorporated herein by reference.

(17) Filed as an exhibit to Registrant's Current Report on Form 8-K/A filed on February 22, 2006, and incorporated herein by reference.

(18) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2007, and incorporated herein by reference.

(19) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2009, and incorporated herein by reference.

(20) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2009, and incorporated herein by reference.

(21) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2011, and incorporated herein by reference.

(22) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2012, and incorporated herein by reference.

(23) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2012, and incorporated herein by reference.

(24) Filed as an exhibit to Registrant's Current Report on Form 8-K first filed on December 19, 2007, and incorporated herein by reference.

(25) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2010, and incorporated herein by reference.

(26) Filed as an exhibit to Registrant's Registration Statement on Form S-8 (No. 333-163871) filed on December 21, 2009, and incorporated herein by reference.

(27) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2001, and incorporated herein by reference.

(28) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2008, and incorporated herein by reference.

(29) Information is included in Registrant's Current Report on Form 8-K filed on February 4, 2013, and incorporated herein by reference.

59

(30) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2008, and incorporated herein by reference.

(31) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2006, and incorporated herein by reference.

(32) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended March 31, 1994, and incorporated herein by reference.

(33) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2000, and incorporated herein by reference.

(34) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2005, and incorporated herein by reference.

(35) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2011, and incorporated herein by reference

(36) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2012, and incorporated herein by reference     

(37) Filed as an exhibit to Triangle Pharmaceuticals, Inc.'s Quarterly Report on Form 10-Q/A filed on November 3, 1999, and incorporated herein by reference.

(38) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2005, and incorporated herein by reference.

(39) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2005, and incorporated herein by reference.

(40) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2011, and incorporated herein by reference.

(41) Filed as an exhibit to Myogen, Inc.'s Registration Statement on Form S-1 (No. 333-108301), as amended, originally filed on August 28, 2003, and incorporated herein by reference.

(42) Filed as an exhibit to Myogen, Inc.'s Quarterly Report on Form 10-Q filed on May 9, 2006, and incorporated herein by reference.

(43) Filed as an exhibit to CV Therapeutics, Inc.'s Registration Statement on Form S-3 (No. 333-59318), as amended, originally filed on April 20, 2001, and incorporated herein by reference.

(44) Filed as an exhibit to CV Therapeutics, Inc.'s Quarterly Report on Form 10-Q for the quarter ended June 30, 2006, and incorporated herein by reference.

(45) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2009, and incorporated herein by reference.

(46) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2003, and incorporated herein by reference.

(47) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on August 7, 2007, and incorporated herein by reference.

(48) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2012, and incorporated herein by reference.

(49) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2012, and incorporated herein by reference.

√ The Agreement and Plan of Merger (the Merger Agreement) contains representations and warranties of Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc. made solely to each other as of specific dates. Those representations and warranties were made solely for purposes of the Merger Agreement and may be subject to important qualifications and limitations agreed to by Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc. Moreover, some of those representations and warranties may not be accurate or complete as of any specified date, may be subject to a standard of materiality provided for in the Merger Agreement and have been used for the purpose of allocating risk among Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc. rather than establishing matters as facts.

† The Agreement and Plan of Merger (the Pharmasset Merger Agreement) contains representations and warranties of Registrant, Merger Sub and Pharmasset, Inc. made solely to each other as of specific dates. Those representations and warranties were made solely for purposes of the Pharmasset Merger Agreement and may be subject to important

60

qualifications and limitations agreed to by Registrant, Merger Sub and Pharmasset, Inc. Moreover, some of those representations and warranties may not be accurate or complete as of any specified date, may be subject to a standard of materiality provided for in the Pharmasset Merger Agreement and have been used for the purpose of allocating risk among Registrant, Merger Sub and Pharmasset, Inc. rather than establishing matters as facts.

* Management contract or compensatory plan or arrangement.

** This certification accompanies the Form 10-Q to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of Registrant under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing.

*** XBRL information is filed herewith.

+ Certain confidential portions of this Exhibit were omitted by means of marking such portions with an asterisk (the Mark). This Exhibit has been filed separately with the Secretary of the SEC without the Mark pursuant to Registrant's Application Requesting Confidential Treatment under Rule 24b-2 under the Securities Exchange Act of 1934, as amended.

61

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

		GILEAD SCIENCES, INC.
		(Registrant)
Date:	May 8, 2013	/s/    JOHN C. MARTIN
		John C. Martin, Ph.D. Chairman and Chief Executive Officer (Principal Executive Officer)
Date:	May 8, 2013	/s/    ROBIN L. WASHINGTON
		Robin L. Washington Senior Vice President and Chief Financial Officer (Principal Financial and Accounting Officer)

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Exhibit Index

Exhibit Footnote		Exhibit Number	Description of Document
√(1)	2.1		Agreement and Plan of Merger among Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc., dated as of March 12, 2009
†(2)	2.5		Agreement and Plan of Merger among Registrant, Merger Sub and Pharmasset, Inc., dated as of November 21, 2011
(3)	3.1		Amended and Restated Certificate of Incorporation of Registrant, as amended and restated on May 8, 2013
(4)	3.2		Amended and Restated Bylaws of Registrant, as amended and restated on May 12, 2011
	4.1		Reference is made to Exhibit 3.1 and Exhibit 3.2
(5)	4.2		Indenture related to the Convertible Senior Notes due 2013 (2013 Notes), between Registrant and Wells Fargo Bank, National Association, as trustee (including form of 0.625% Convertible Senior Note due 2013), dated April 25, 2006
(6)	4.3		Indenture related to the Convertible Senior Notes due 2014 (2014 Notes), between Registrant and Wells Fargo Bank, National Association, as trustee (including form of 1.00% Convertible Senior Note due 2014), dated July 30, 2010
(6)	4.4		Indenture related to the Convertible Senior Notes due 2016 (2016 Notes), between Registrant and Wells Fargo Bank, National Association, as trustee (including form of 1.625% Convertible Senior Note due 2016), dated July 30, 2010
(7)	4.5		Indenture related to Senior Notes, dated as of March 30, 2011, between Registrant and Wells Fargo, National Association, as Trustee
(7)	4.6		First Supplemental Indenture related to Senior Notes, dated as of March 30, 2011, between Registrant and Wells Fargo, National Association, as Trustee (including form of Senior Notes)
(8)	4.7		Second Supplemental Indenture related to Senior Notes, dated as of December 13, 2011, between Registrant and Wells Fargo, National Association, as Trustee (including Form of 2014 Note, Form of 2016 Note, Form of 2021 Note, Form of 2041 Note)
(9)	10.1		Confirmation of OTC Convertible Note Hedge related to 2013 Notes, dated April 19, 2006, as amended and restated as of April 24, 2006, between Registrant and Bank of America, N.A.
(9)	10.2		Confirmation of OTC Warrant Transaction, dated April 19, 2006, as amended and restated as of April 24, 2006, between Registrant and Bank of America, N.A. for warrants expiring in 2013
(10)	10.3		Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated July 26, 2010, between Registrant and Goldman, Sachs & Co.
(10)	10.4		Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association
(10)	10.5		Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated July 26, 2010, between Registrant and Goldman, Sachs & Co.
(10)	10.6		Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association
(10)	10.7		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2014
(10)	10.8		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2014
(10)	10.9		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2016
(10)	10.10		Confirmation of OTC Warrant Transaction, dated July 26, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2016

63

Exhibit Footnote		Exhibit Number	Description of Document
(11)	10.11		Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 5, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.12		Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.13		Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 5, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.14		Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.15		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2014
(11)	10.16		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2014
(11)	10.17		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and Goldman, Sachs & Co. for warrants expiring in 2016
(11)	10.18		Confirmation of OTC Additional Warrant Transaction, dated August 5, 2010, between Registrant and JPMorgan Chase Bank, National Association for warrants expiring in 2016
(11)	10.19		Amendment to Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.20		Amendment to Confirmation of OTC Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.21		Amendment to Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.22		Amendment to Confirmation of OTC Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.23		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.24		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2014 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(11)	10.25		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and Goldman, Sachs & Co.
(11)	10.26		Amendment to Confirmation of OTC Additional Convertible Note Hedge related to 2016 Notes, dated August 30, 2010, between Registrant and JPMorgan Chase Bank, National Association
(12)	10.27		5-Year Revolving Credit Facility Credit Agreement among Registrant and Gilead Biopharmaceutics Ireland Corporation, as Borrowers, Bank of America, N.A., as Administrative Agent, Swing Line Lender and L/C Issuer, certain other lenders parties thereto, Barclays Capital, as Syndication Agent, and Goldman Sachs Bank USA, JPMorgan Chase Bank, N.A., Royal Bank of Canada and Wells Fargo Bank, N.A., as Co-Documentation Agents, dated as of January 12, 2012
(12)	10.28		Parent Guaranty Agreement (5-Year Revolving Credit Facility), dated as of January 12, 2012, by Registrant
*(13)	10.29		Gilead Sciences, Inc. 1991 Stock Option Plan, as amended through January 29, 2003
*(14)	10.30		Form of option agreements used under the 1991 Stock Option Plan
*(13)	10.31		Gilead Sciences, Inc. 1995 Non-Employee Directors' Stock Option Plan, as amended through January 30, 2002

64

Exhibit Footnote		Exhibit Number	Description of Document
*(14)	10.32		Form of option agreement used under the Gilead Sciences, Inc. 1995 Non-Employee Directors' Stock Option Plan
*(16)	10.33		Gilead Sciences, Inc. 2004 Equity Incentive Plan, as amended through May 6, 2009
*(17)	10.34		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants prior to February 2008)
*(18)	10.35		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants made February 2008 through April 2009)
*(19)	10.36		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants commencing in May 2009)
*(20)	10.37		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for grants commencing in February 2010)
*(21)	10.38		Form of employee stock option agreement used under 2004 Equity Incentive Plan (for 2011 and subsequent year grants)
*(18)	10.39		Form of non-employee director stock option agreement used under 2004 Equity Incentive Plan (for grants prior to 2008)
*(18)	10.40		Form of non-employee director option agreement used under 2004 Equity Incentive Plan (for initial grants made in 2008)
*(18)	10.41		Form of non-employee director option agreement used under 2004 Equity Incentive Plan (for annual grants made in May 2008)
*(19)	10.42		Form of non-employee director option agreement used under 2004 Equity Incentive Plan (for annual grants commencing in May 2009)
*(22)	10.43		Form of restricted stock unit issuance agreement used under 2004 Equity Incentive Plan (for annual grants to non-employee directors commencing in May 2012)
*(19)	10.44		Form of restricted stock award agreement used under 2004 Equity Incentive Plan (for annual grants to certain non-employee directors prior to May 2012)
*(19)	10.45		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2009)
*(20)	10.46		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2010)
*(21)	10.47		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2011)
*(23)	10.48		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made in 2012)
*	10.49		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for TSR Goals in 2013)
*	10.50		Form of performance share award agreement used under the 2004 Equity Incentive Plan (for Revenue Goals in 2013)
*(24)	10.51		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers made prior to May 2009)
*(19)	10.52		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (for grants to certain executive officers commencing in May 2009)
*(25)	10.53		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (service-based vesting for certain executive officers commencing in November 2009)

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Exhibit Footnote		Exhibit Number	Description of Document
*(21)	10.54		Form of restricted stock unit issuance agreement used under the 2004 Equity Incentive Plan (service-based vesting for certain executive officers commencing in 2011)
*(20)	10.55		Gilead Sciences, Inc. Employee Stock Purchase Plan, amended and restated on November 3, 2009
*(26)	10.56		Gilead Sciences, Inc. International Employee Stock Purchase Plan, adopted November 3, 2009
*(27)	10.57		Gilead Sciences, Inc. Deferred Compensation Plan-Basic Plan Document
*(27)	10.58		Gilead Sciences, Inc. Deferred Compensation Plan-Adoption Agreement
*(27)	10.59		Addendum to the Gilead Sciences, Inc. Deferred Compensation Plan
*(28)	10.60		Gilead Sciences, Inc. 2005 Deferred Compensation Plan, as amended and restated on October 23, 2008
*(23)	10.61		Gilead Sciences, Inc. Severance Plan, as amended on January 26, 2012
*(17)	10.62		Gilead Sciences, Inc. Corporate Bonus Plan
*(4)	10.63		Amended and Restated Gilead Sciences, Inc. Code Section 162(m) Bonus Plan
*(29)	10.64		2013 Base Salaries for the Named Executive Officers
*(30)	10.65		Offer Letter dated April 16, 2008 between Registrant and Robin Washington
*(14)	10.66		Form of Indemnity Agreement entered into between Registrant and its directors and executive officers
*(14)	10.67		Form of Employee Proprietary Information and Invention Agreement entered into between Registrant and certain of its officers and key employees
*(20)	10.68		Form of Employee Proprietary Information and Invention Agreement entered into between Registrant and certain of its officers and key employees (revised in September 2006)
(31)	10.69		Amended and Restated Collaboration Agreement by and among Registrant, Gilead Holdings, LLC, Bristol-Myers Squibb Company, E.R. Squibb & Sons, L.L.C., and Bristol-Myers Squibb & Gilead Sciences, LLC, dated September 28, 2006
(18)	10.70		Commercialization Agreement by and between Gilead Sciences Limited and Bristol-Myers Squibb Company, dated December 10, 2007
(32)	10.71		Amendment Agreement, dated October 25, 1993, between Registrant, the Institute of Organic Chemistry and Biochemistry (IOCB) and Rega Stichting v.z.w. (REGA), together with the following exhibits: the License Agreement, dated December 15, 1991, between Registrant, IOCB and REGA (the 1991 License Agreement), the License Agreement, dated October 15, 1992, between Registrant, IOCB and REGA (the October 1992 License Agreement) and the License Agreement, dated December 1, 1992, between Registrant, IOCB and REGA (the December 1992 License Agreement)
(33)	10.72		Amendment Agreement between Registrant and IOCB/REGA, dated December 27, 2000 amending the 1991 License Agreement and the December 1992 License Agreement
(31)	10.73		Sixth Amendment Agreement to the License Agreement, between IOCB/REGA and Registrant, dated August 18, 2006 amending the October 1992 License Agreement and the December 1992 License Agreement
(31)	10.74		Development and License Agreement among Registrant and F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc., dated September 27, 1996
(34)	10.75		First Amendment and Supplement dated November 15, 2005 to the Development and Licensing Agreement between Registrant, F. Hoffmann-La Roche Ltd and Hoffman-La Roche Inc. dated September 27, 1996

66

Exhibit Footnote		Exhibit Number	Description of Document
(35)	10.76		Second Amendment dated December 22, 2011 to the Development and Licensing Agreement between Registrant, F. Hoffmann-La Roche Ltd and Hoffman-La Roche Inc. dated September 27, 1996
+ (36)	10.77		Third Amendment dated October 5, 2012 to the Development and Licensing Agreement between Registrant, F. Hoffmann-La Roche Ltd and Hoffman-La Roche Inc. dated September 27, 1996
(37)	10.78		Exclusive License Agreement between Registrant (as successor to Triangle Pharmaceuticals, Inc.), Glaxo Group Limited, The Wellcome Foundation Limited, Glaxo Wellcome Inc. and Emory University, dated May 6, 1999
(38)	10.79		Royalty Sale Agreement by and among Registrant, Emory University and Investors Trust & Custodial Services (Ireland) Limited, solely in its capacity as Trustee of Royalty Pharma, dated July 18, 2005
(38)	10.80		Amended and Restated License Agreement between Registrant, Emory University and Investors Trust & Custodial Services (Ireland) Limited, solely in its capacity as Trustee of Royalty Pharma, dated July 21, 2005
(39)	10.81		License Agreement between Japan Tobacco Inc. and Registrant, dated March 22, 2005
(40)	10.82		First Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated May 19, 2005
(40)	10.83		Second Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated May 17, 2010
(40)	10.84		Third Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated July 5, 2011
(40)	10.85		Fourth Amendment to License Agreement between Japan Tobacco Inc. and Registrant, dated July 5, 2011
(41)	10.86		License Agreement between Registrant (as successor to Myogen, Inc.) and Abbott Deutschland Holding GmbH dated October 8, 2001
+(42)	10.87		License Agreement between Registrant (as successor to Myogen, Inc.) and Glaxo Group Limited, dated March 3, 2006
(41)	10.88		License Agreement between Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated March 27, 1996
(43)	10.89		First Amendment to License Agreement between Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated July 3, 1997
(43)	10.90		Amendment No. 2 to License Agreement between Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated November 30. 1999
(44)	10.91		Amendment No. 4 to License Agreement with Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated June 20, 2006
(35)	10.92		Amendment No. 5 to License Agreement with Registrant (as successor to CV Therapeutics, Inc.) and Roche Palo Alto LLC (successor in interest by merger to Syntex (U.S.A.) Inc.), dated December 22, 2011
(45)	10.93		License and Collaboration Agreement by and among Registrant, Gilead Sciences Limited and Janssen R&D Ireland (formerly Tibotec Pharmaceuticals), dated July 16, 2009
(40)	10.94		Second Amendment to License and Collaboration Agreement by and among Registrant, Gilead Sciences Limited and Janssen R&D Ireland (formerly Tibotec Pharmaceuticals), dated July 1, 2011

67

Exhibit Footnote		Exhibit Number	Description of Document
+	10.95		Amended and Restated Second Amendment to License and Collaboration Agreement by and among Registrant, Gilead Sciences Limited and Janssen R&D Ireland (formerly Tibotec Pharmaceuticals), dated February 7, 2013
(46)	10.96		Master Clinical and Commercial Supply Agreement between Gilead World Markets, Limited, Registrant and Patheon Inc., dated January 1, 2003
(38)	10.97		Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama), Ltd., dated July 17, 2003
(47)	10.98		Addendum to Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama) Ltd., dated May 10, 2007
(28)	10.99		Addendum to Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama) Ltd., dated December 5, 2008
(21)	10.100		Addendum to Tenofovir Disoproxil Fumarate Manufacturing Supply Agreement by and between Gilead Sciences Limited and PharmaChem Technologies (Grand Bahama) Ltd., dated February 3. 2011
(34)	10.101		Restated and Amended Toll Manufacturing Agreement between Gilead Sciences Limited, Registrant and Nycomed GmbH (formerly ALTANA Pharma Oranienburg GmbH), dated November 7, 2005
+(9)	10.102		Emtricitabine Manufacturing Supply Agreement between Gilead Sciences Limited and Evonik Degussa GmbH (formerly known as Degussa AG), dated June 6, 2006
+(10)	10.103		Amendment No. 1 to Emtricitabine Manufacturing Supply Agreement between Gilead Sciences Limited and Evonik Degussa GmbH (formerly known as Degussa AG), dated April 30, 2010
(48)	10.104		Purchase and Sale Agreement and Joint Escrow Instructions between Electronics for Imaging, Inc. and Registrant, dated July 18, 2012
(49)	10.105		Amendment No. 1, dated October 30, 2012, to the Purchase and Sale Agreement and Joint Escrow Instructions between Electronics for Imaging, Inc. and Registrant, dated July 18, 2012
	31.1		Certification of Chief Executive Officer, as required by Rule 13a-14(a) or Rule 15d-14(a) of the Securities Exchange Act of 1934, as amended
	31.2		Certification of Chief Financial Officer, as required by Rule 13a-14(a) or Rule 15d-14(a) of the Securities Exchange Act of 1934, as amended
	32.1**		Certifications of Chief Executive Officer and Chief Financial Officer, as required by Rule 13a-14(b) or Rule 15d-14(b) and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. §1350)
	101***		The following materials from Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2013, formatted in Extensible Business Reporting Language (XBRL) includes: (i) Consolidated Balance Sheets, (ii) Consolidated Statements of Income, (iii) Consolidated Statements of Comprehensive Income, (iv) Consolidated Statements of Cash Flows and (v) Notes to Consolidated Financial Statements.

(1) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on March 12, 2009, and incorporated herein by reference.

(2) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on November 25, 2011, and incorporated herein by reference.

(3) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on May 8, 2013, and incorporated herein by reference.

(4) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on May 17, 2011, and incorporated herein by reference.

68

(5) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on April 25, 2006, and incorporated herein by reference.

(6) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on August 2, 2010, and incorporated herein by reference.

(7) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on April 1, 2011, and incorporated herein by reference.

(8) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on December 13, 2011, and incorporated herein by reference.

(9) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2006, and incorporated herein by reference.

(10) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2010, and incorporated herein by reference.

(11) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2010, and incorporated herein by reference.

(12) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on January 17, 2012, and incorporated herein by reference.

(13) Filed as an exhibit to Registrant's Registration Statement on Form S-8 (No. 333-102912) filed on January 31, 2003, and incorporated herein by reference.

(14) Filed as an exhibit to Registrant's Registration Statement on Form S-1 (No. 33-55680), as amended, and incorporated herein by reference.

(15) Filed as an exhibit to Registrant's Annual Report on Form 10-K/A for the fiscal year ended December 31, 1998, and incorporated herein by reference.

(16) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on May 11, 2009, and incorporated herein by reference.

(17) Filed as an exhibit to Registrant's Current Report on Form 8-K/A filed on February 22, 2006, and incorporated herein by reference.

(18) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2007, and incorporated herein by reference.

(19) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2009, and incorporated herein by reference.

(20) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2009, and incorporated herein by reference.

(21) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2011, and incorporated herein by reference.

(22) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2012, and incorporated herein by reference.

(23) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2012, and incorporated herein by reference.

(24) Filed as an exhibit to Registrant's Current Report on Form 8-K first filed on December 19, 2007, and incorporated herein by reference.

(25) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2010, and incorporated herein by reference.

(26) Filed as an exhibit to Registrant's Registration Statement on Form S-8 (No. 333-163871) filed on December 21, 2009, and incorporated herein by reference.

(27) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2001, and incorporated herein by reference.

(28) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2008, and incorporated herein by reference.

(29) Information is included in Registrant's Current Report on Form 8-K filed on February 4, 2013, and incorporated herein by reference.

69

(30) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended June 30, 2008, and incorporated herein by reference.

(31) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2006, and incorporated herein by reference.

(32) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended March 31, 1994, and incorporated herein by reference.

(33) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2000, and incorporated herein by reference.

(34) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2005, and incorporated herein by reference.

(35) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2011, and incorporated herein by reference

(36) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2012, and incorporated herein by reference     

(37) Filed as an exhibit to Triangle Pharmaceuticals, Inc.'s Quarterly Report on Form 10-Q/A filed on November 3, 1999, and incorporated herein by reference.

(38) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2005, and incorporated herein by reference.

(39) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 2005, and incorporated herein by reference.

(40) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2011, and incorporated herein by reference.

(41) Filed as an exhibit to Myogen, Inc.'s Registration Statement on Form S-1 (No. 333-108301), as amended, originally filed on August 28, 2003, and incorporated herein by reference.

(42) Filed as an exhibit to Myogen, Inc.'s Quarterly Report on Form 10-Q filed on May 9, 2006, and incorporated herein by reference.

(43) Filed as an exhibit to CV Therapeutics, Inc.'s Registration Statement on Form S-3 (No. 333-59318), as amended, originally filed on April 20, 2001, and incorporated herein by reference.

(44) Filed as an exhibit to CV Therapeutics, Inc.'s Quarterly Report on Form 10-Q for the quarter ended June 30, 2006, and incorporated herein by reference.

(45) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2009, and incorporated herein by reference.

(46) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2003, and incorporated herein by reference.

(47) Filed as an exhibit to Registrant's Current Report on Form 8-K filed on August 7, 2007, and incorporated herein by reference.

(48) Filed as an exhibit to Registrant's Quarterly Report on Form 10-Q for the quarter ended September 30, 2012, and incorporated herein by reference.

(49) Filed as an exhibit to Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2012, and incorporated herein by reference.

√ The Agreement and Plan of Merger (the Merger Agreement) contains representations and warranties of Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc. made solely to each other as of specific dates. Those representations and warranties were made solely for purposes of the Merger Agreement and may be subject to important qualifications and limitations agreed to by Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc. Moreover, some of those representations and warranties may not be accurate or complete as of any specified date, may be subject to a standard of materiality provided for in the Merger Agreement and have been used for the purpose of allocating risk among Registrant, Apex Merger Sub, Inc. and CV Therapeutics, Inc. rather than establishing matters as facts.

† The Agreement and Plan of Merger (the Pharmasset Merger Agreement) contains representations and warranties of Registrant, Merger Sub and Pharmasset, Inc. made solely to each other as of specific dates. Those representations and warranties were made solely for purposes of the Pharmasset Merger Agreement and may be subject to important

70

qualifications and limitations agreed to by Registrant, Merger Sub and Pharmasset, Inc. Moreover, some of those representations and warranties may not be accurate or complete as of any specified date, may be subject to a standard of materiality provided for in the Pharmasset Merger Agreement and have been used for the purpose of allocating risk among Registrant, Merger Sub and Pharmasset, Inc. rather than establishing matters as facts.

* Management contract or compensatory plan or arrangement.

** This certification accompanies the Form 10-Q to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of Registrant under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing.

*** XBRL information is filed herewith.

+ Certain confidential portions of this Exhibit were omitted by means of marking such portions with an asterisk (the Mark). This Exhibit has been filed separately with the Secretary of the SEC without the Mark pursuant to Registrant's Application Requesting Confidential Treatment under Rule 24b-2 under the Securities Exchange Act of 1934, as amended.

71

EX-10.49

Exhibit 10.49

TSR PERFORMANCE GOAL

GILEAD SCIENCES, INC.

PERFORMANCE SHARE AWARD AGREEMENT

RECITALS

A.    The Corporation has implemented the Plan for the purpose of providing incentives to attract, retain and motivate eligible Employees, Directors and Consultants to continue their service relationship with the Corporation.

B.    Participant is to render valuable services to the Corporation (or a Related Entity), and this Agreement is executed pursuant to, and is intended to carry out the purposes of, the Plan in connection with the Corporation's issuance of shares of Common Stock to Participant thereunder.

C.    All capitalized terms in this Agreement shall have the meaning assigned to them herein or in the attached Appendix A.

NOW, THEREFORE, it is hereby agreed as follows:

1.Grant of Performance Shares. The Corporation hereby awards to Participant, as of the Award Date indicated below, an award (the “Award”) of Performance Shares under the Corporation's 2004 Equity Incentive Plan, as amended (the “Plan”). Each Performance Share which vests pursuant to the terms of this Agreement shall provide Participant with the right to receive one or more shares of Common Stock on the designated issuance date for those shares. The number of Performance Shares subject to this Award, the applicable performance-vesting and service-vesting requirements for those Performance Shares, the date or dates on which the shares of Common Stock that vest hereunder shall become issuable and the remaining terms and conditions governing the Award, including the applicable vesting acceleration provisions, shall be as set forth in this Agreement.

AWARD SUMMARY

Participant	[FIRST NAME MIDDLE NAME LAST NAME]
Award Date:	[GRANT DATE]
Designated Number of Performance Shares:	The actual number of shares of Common Stock that may become issuable pursuant to the Performance Shares awarded under this Agreement shall be determined in accordance with the applicable performance-vesting and service-vesting provisions of this Agreement. For purposes of the applicable calculations to be made under those vesting provisions, the total designated number of Performance Shares to be utilized is [SHARES] shares (the “Performance Shares”).

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Vesting Schedule:

Vesting Requirements. The Performance Shares shall be subject to the performance-vesting requirements set forth in attached Schedule I and the service-vesting requirements set forth in Paragraph 3 of this Agreement. Change in Control Vesting. The Performance Shares and the underlying shares of Common Stock may also vest on an accelerated basis in accordance with the applicable provisions of Paragraph 5 of this Agreement should a Change in Control occur after the start but prior to the completion of the Performance Period applicable to the Performance Shares.

Issuance Date:

The shares of Common Stock which actually vest and become issuable pursuant to the Performance Shares subject to this Award shall be issued in accordance with the provisions of this Agreement applicable to the particular circumstances under which such vesting occurs.

2.Limited Transferability. Prior to the actual issuance of the shares of Common Stock which vest hereunder, Participant may not transfer any interest in the Performance Shares subject to this Award or the underlying shares of Common Stock or pledge or otherwise hedge the sale of those Performance Shares or underlying shares, including (without limitation) any short sale or any acquisition or disposition of any put or call option or other instrument tied to the value of the underlying shares of Common Stock. However, any shares of Common Stock which vest hereunder but otherwise remain unissued at the time of Participant's death may be transferred pursuant to the provisions of Participant's will or the laws of inheritance or to Participant's designated beneficiary or beneficiaries of this Award. Participant may also direct the Corporation to record the ownership of any shares of Common Stock which in fact vest and become issuable hereunder in the name of a revocable living trust established for the exclusive benefit of Participant or Participant and his or her spouse. Participant may make such a beneficiary designation or ownership directive at any time by completing the Corporation's Universal Beneficiary Designation form and filing the completed form with the Plan Administrator or its designee.

3.Continuous Service Vesting Requirement.The number of shares of Common Stock in which Participant may actually vest on the basis of the number of Performance-Qualified Shares certified by the Administrator in accordance with the performance-vesting provisions of attached Schedule I shall be tied to his or her completion of the following Continuous Service vesting requirements:

(a)If Participant remains in Continuous Service through the date following the completion of the Performance Period on which the Administrator certifies the attained level of the TSR Performance Goal for such Performance Period, Participant shall vest in the maximum number of Performance-Qualified Shares based on the actual level at which the TSR Performance Goal is attained and certified for the Performance Period.

(b)If Participant's Continuous Service terminates prior to the completion of the Performance Period (or after the completion of the Performance Period but before the date the Administrator certifies the attained level of the TSR Performance Goal) by reason of death or Permanent Disability, then Participant shall, following the completion of the Performance Period, vest in that number of shares of Common Stock (if any) determined by multiplying the maximum number of Performance-Qualified Shares in which Participant could vest, based on the actual level at which the TSR Performance Goal is attained and certified for the Performance Period, by a fraction, the numerator of which is the number of months of Continuous Service actually completed by Participant in the Performance Period (rounded to the closest whole month), and the denominator of which is the number of months (rounded to the closest whole number) constituting the entire Performance Period.

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(c)If Participant's Continuous Service terminates by reason of his or her Retirement at any time after the completion of the first twelve (12) months of the Performance Period but prior to the completion of the entire Performance Period (or after the completion of the Performance Period but before the date the Administrator certifies the attained level of the TSR Performance Goal for the Performance Period), then Participant shall, following the completion of the Performance Period, vest in that number of shares of Common Stock (if any) determined by multiplying the maximum number of Performance-Qualified Shares in which Participant could vest, based on the actual level at which the TSR Performance Goal is attained and certified for the Performance Period, by a fraction, the numerator of which is the number of months of Continuous Service actually completed by Participant in such Performance Period prior to his or her Retirement (rounded to the closest whole month), and the denominator of which is the number of months (rounded to the closest whole number) constituting the entire Performance Period.

(d)If (i) Participant's Continuous Service terminates by reason of an involuntary termination other than for Cause, or his or her resignation due to Constructive Termination, at any time after the completion of the Performance Period but before the date the Administrator certifies the attained level of the TSR Performance Goal for that Performance Period and (ii) such termination of Continuous Service also occurs during a period while there is in effect a definitive executed agreement for the Change in Control transaction, then Participant shall vest in the maximum number of Performance-Qualified Shares in which Participant could vest, based on the actual level at which the TSR Performance Goal is attained and certified for the Performance Period, had Participant remained in Continuous Service through such certification date.

(e)If Participant's Continuous Service ceases for any other reason (including, without limitation, any deemed cessation of Continuous Service under Paragraph 9) prior to the completion of the Performance Period or prior to the date on which the Administrator certifies the attained level of the TSR Performance Goal for the Performance Period, then Participant shall not vest in any of the Performance-Qualified Shares, and all of Participant's right, title and interest to the shares of Common Stock subject to this Award shall immediately terminate; provided, however, that should a Change in Control occur prior to the completion of the Performance Period, then the provisions of Paragraph 5 shall govern the vesting of the Performance Shares subject to this Award.

4.Stockholder Rights and Dividend Equivalents

(a)The holder of this Award shall not have any stockholder rights, including voting, dividend or liquidation rights, with respect to the shares of Common Stock subject to the Award until Participant becomes the record holder of those shares upon their actual issuance following the Corporation's collection of the applicable Withholding Taxes. Notwithstanding the foregoing, should any dividend or other distribution, whether regular or extraordinary and whether payable in cash, securities (other than Common Stock) or other property, be declared and paid on the outstanding Common Stock while one or more Performance Shares remain subject to this Award (i.e., the underlying shares of Common Stock are not otherwise issued and outstanding for purposes of entitlement to the dividend or distribution), then a special book account shall be established for Participant and credited with a phantom dividend equivalent to the actual dividend or distribution that would have been paid on the maximum number of shares of Common Stock that can qualify as Performance-Qualified Shares under this Award, had that number of shares been issued and outstanding and entitled to that dividend or distribution. As one or more shares of Common Stock subsequently vest hereunder upon the satisfaction of the applicable vesting requirements for those shares, the phantom dividend equivalents credited to those particular shares in the book account shall vest, and those vested dividend equivalents shall be distributed to Participant (in the same form the actual dividend or distribution was paid to the holders of the Common Stock entitled to that dividend or distribution or in such other form as the Administrator deems appropriate under the circumstances) concurrently with the issuance of those vested shares. However, such distribution shall be subject to the Corporation's collection of the

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Withholding Taxes applicable to that distribution. To the extent any phantom dividend equivalents are to be distributed in shares of Common Stock, the following conversion process will be in effect.  For each such dividend or distribution that is to be converted into shares of Common Stock, the aggregate dollar value of the cash, securities or other property that would have been paid as an actual dividend or distribution on the shares of Common Stock subject to this Award had they been actually issued and outstanding shares at the time of such dividend or distribution will be divided by the Fair Market Value per share of Common Stock measured as of the date on which such dividend or distribution was paid on the outstanding Common Stock, with any fractional share of Common Stock rounded down to the next whole share of Common Stock.  The Administrator shall have the sole discretion to determine the dollar value of any such dividend or distribution paid other than in the form of cash, and its determination shall be controlling.  

(b)To the extent the maximum number of shares of Common Stock that can qualify as Performance-Qualified Shares under this Award is not in fact earned by reason of the level at which the Performance Goal is actually attained, then the phantom dividend equivalents credited to those unearned shares shall be cancelled, and Participant shall cease to have any right or entitlement to receive any distributions or other amounts with respect to those cancelled dividend equivalents.

(c)Should Participant cease Continuous Service without vesting in one or more of the shares of Common Stock subject to this Award (including any shares which do not otherwise vest at that time after taking into account any applicable vesting acceleration provisions set forth in this Agreement), then the phantom dividend equivalents credited to those unvested shares shall be cancelled, and Participant shall thereupon cease to have any further right or entitlement to those cancelled amounts.

5.Change in Control. The following provisions shall apply only to the extent a Change in Control is consummated prior to the completion of the Performance Period and shall have no force or effect if the effective date of the Change in Control occurs after the completion date of the Performance Period:

(a)Should (i) the Change in Control occur within the first twelve (12) months of the Performance Period and (ii) Participant remain in Continuous Service through the effective date of that Change in Control, then Participant shall immediately vest in that number of shares of Common Stock equal to the designated number of Performance Shares subject to this Award, without any measurement of Performance Goal attainment to date.

(b)Should (i) the Change in Control occur at any time on or after the completion of the first twelve (12) months of the Performance Period but prior to the completion of the entire Performance Period and (ii) Participant remain in Continuous Service through the effective date of that Change in Control, then Participant shall immediately vest in that number of shares of Common Stock equal to the greater of (i) the designated number of Performance Shares subject to this Award or (ii) the number of Performance-Qualified Shares determined by multiplying (A) the designated number of Performance Shares subject to this Award by (B) the applicable percentage (determined in accordance with the payout slope set forth in attached Schedule I) for the level at which the TSR Performance Goal is attained over an abbreviated Performance Period ending with the close of the Corporation's fiscal quarter coincident with or immediately preceding the effective date of the Change in Control.

(c)The foregoing provisions of this Paragraph 5 shall also apply should Participant's Continuous Service terminate, by reason of an involuntary termination other than for Cause or his or her resignation due to Constructive Termination, at any time during the period beginning with the execution date of the definitive agreement for the Change in Control transaction and ending with the earlier of (i) the effective date of that Change in Control or (ii) the termination of the definitive agreement without

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the consummation of the Change in Control; provided, however, that in no event shall Participant become entitled to any shares of Common Stock pursuant to this Paragraph 5 if the Change in Control is not in fact consummated.

(d)Should Participant cease Continuous Service during the Performance Period by reason of death or Permanent Disability and a Change in Control subsequently occur prior to the completion of that Performance Period, then Participant shall, at the time of such Change in Control, vest in a pro-rated number of shares of Common Stock calculated by multiplying (i) the number of Performance Shares or Performance-Qualified Shares determined in accordance with the applicable provisions of subparagraphs (a) and (b) of this Paragraph 5 by (ii) a fraction, the numerator of which is the number of months of Continuous Service actually completed by Participant in the Performance Period (rounded to the closest whole month), and the denominator of which is the number of months (rounded to the closest whole number) comprising the portion of such Performance Period ending with the earlier of (i) the effective date of the Change in Control or (ii) the last day of the abbreviated Performance Period (if any) taken into account under clause (ii) of Paragraph 5(b).

(e)Should Participant cease Continuous Service by reason of his or her Retirement at any time after the completion of the first twelve (12) months of the Performance Period but prior to the completion of the entire Performance Period and a Change in Control subsequently occur prior to the completion of that Performance Period, then Participant shall, at the time of such Change in Control, vest in a pro-rated number of shares of Common Stock calculated by multiplying (i) the number of Performance Shares or Performance-Qualified Shares determined in accordance with the provisions of subparagraph (b) of this Paragraph 5 by (ii) a fraction, the numerator of which is the number of months of Continuous Service actually completed by Participant in such Performance Period prior to his or her Retirement (rounded to the closest whole month), and the denominator of which is the number of months (rounded to the closest whole number) comprising the portion of such Performance Period ending with the earlier of (i) the effective date of the Change in Control or (ii) the last day of the abbreviated Performance Period (if any) taken into account under clause (ii) of Paragraph 5(b).

(f)The number of shares of Common Stock in which Participant vests on the basis of the Performance Shares or Performance-Qualified Shares determined in accordance with the foregoing provisions of this Paragraph 5 shall be converted into the right to receive for each such share the same consideration per share of Common Stock payable to the other stockholders of the Corporation in consummation of the Change in Control, and such consideration shall be distributed to Participant on the tenth (10th) business day following the effective date of that Change in Control, unless a later issuance date is in effect for those shares pursuant to any deferral election made by Participant pursuant to Paragraph 8. Each issuance or distribution made under this Paragraph 5(f) shall be subject to the Corporation's collection of the applicable Withholding Taxes.

(g)Except for the actual number of shares of Common Stock in which Participant vests in accordance with this Paragraph 5, Participant shall cease to have any further right or entitlement to any additional shares of Common Stock under this Agreement following the effective date of the Change in Control.

(h)This Agreement shall not in any way affect the right of the Corporation to adjust, reclassify, reorganize or otherwise change its capital or business structure or to merge, consolidate, dissolve, liquidate or sell or transfer all or any part of its business or assets.

6.Adjustment in Shares. Should any change be made to the Common Stock by reason of any stock split, stock dividend, recapitalization, combination of shares, exchange of shares, spin-off

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transaction, extraordinary dividend or distribution or other change affecting the outstanding Common Stock as a class without the Corporation's receipt of consideration, or should the value of the outstanding shares of Common Stock be substantially reduced as a result of a spin-off transaction or an extraordinary dividend or distribution, or should there occur any merger, consolidation or other reorganization, then equitable adjustments shall be made by the Administrator to the total number and/or class of securities issuable pursuant to this Award in order to reflect such change. In making such equitable adjustments, the Administrator shall take into account any amounts credited to Participant's book account under Paragraph 3(a) in connection with the transaction, and the determination of the Administrator shall be final, binding and conclusive. In the event of any Change in Control transaction, the provisions of Paragraph 5 shall be controlling.

7.Issuance or Distribution of Vested Shares or Other Amounts.

(a)Except as otherwise provided in Paragraph 5 or Paragraph 8, the shares of Common Stock in which Participant vests pursuant to the performance-vesting provisions of attached Schedule I and the Continuous Service vesting provisions of this Agreement shall be issued in accordance with the following provision:

-    The issuance of such shares of Common Stock shall be effected during the period beginning on the first business day of February of the calendar year in which the Performance Period ends and ending no later than March 15 of that calendar year.

(b)The Corporation shall, on the applicable issuance date, issue to or on behalf of Participant a certificate in electronic form for the shares of Common Stock in which Participant vests pursuant to the performance-vesting provisions of attached Schedule I and the Continuous Service vesting provisions of this Agreement shall concurrently distribute to Participant any phantom dividend equivalents with respect to those shares. In lieu of such electronic delivery of the shares, Participant may request actual stock certificates for those shares.

(c)Except as otherwise provided in Paragraph 5, no shares of Common Stock shall be issued prior to the completion of the Performance Period. No fractional shares of Common Stock shall be issued pursuant to this Award, and any fractional share resulting from any calculation made in accordance with the terms of this Agreement shall be rounded down to the next whole share.

(d)Regardless of any action the Corporation and/or the Employer take with respect to any or all Withholding Taxes related to Participant's participation in the Plan and legally applicable to Participant, Participant acknowledges that the ultimate liability for all Withholding Taxes is and remains Participant's responsibility and may exceed the amount actually withheld by the Corporation or the Employer. Participant further acknowledges that the Corporation and/or the Employer (i) make no representations or undertakings regarding the treatment of any Withholding Taxes in connection with any aspect of the Award, including the grant, vesting or settlement of the Award, the issuance of shares of Common Stock or other property in settlement of the Award, the subsequent sale of the shares of Common Stock acquired pursuant to such issuance and the receipt of any dividends and/or phantom dividend equivalents and (ii) do not commit to, and are under no obligation to, structure the terms of the grant or any aspect of the Award to reduce or eliminate Participant's liability for Withholding Taxes or achieve any particular tax result. Further, if Participant has become subject to Withholding Taxes in more than one jurisdiction between the Award Date and the date of any relevant taxable or tax withholding event (as applicable), Participant acknowledges that the Corporation and/or the Employer (or former employer, as applicable) may be required to withhold or account for Withholding Taxes in more than one jurisdiction.

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(e)The Corporation shall collect, and Participant hereby authorizes the Corporation to collect, the Withholding Taxes with respect to the shares of Common Stock issued under this Agreement (including shares of Common Stock issued in settlement of phantom dividend equivalents) through an automatic share withholding procedure pursuant to which the Corporation will withhold, immediately as the shares of Common Stock are issued under the Award, a portion of those shares with a Fair Market Value (measured as of the issuance date) equal to the amount of such Withholding Taxes (the “Share Withholding Method”). Notwithstanding the foregoing, the Share Withholding Method shall not be utilized if (i) such method is not permissible or advisable under local law or (ii) the Corporation otherwise decides no longer to utilize such method and provides Participant with notice to such effect.

(f)If the Share Withholding Method is to be utilized for the collection of Withholding Taxes, then the Corporation shall withhold the number of otherwise issuable shares of Common Stock necessary to satisfy the applicable Withholding Taxes based on the applicable minimum statutory rate or other applicable withholding rate. If the obligation for Withholding Taxes is satisfied by using the Share Withholding Method, then Participant will, for tax purposes, be deemed to have been issued the full number of shares of Common Stock subject to the vested Award, notwithstanding that a number of shares of Common Stock are withheld solely for the purpose of paying the applicable Withholding Taxes.

(g)The Corporation shall have sole discretion to determine whether or not the Share Withholding Method shall be utilized for the collection of the applicable Withholding Taxes. Participant shall be notified (in writing or through the Corporation's electronic mail system) in the event the Corporation no longer intends to utilize the Share Withholding Method. Should any shares of Common Stock become issuable under the Award (including shares of Common Stock issued in settlement of phantom dividend equivalents) at a time when the Share Withholding Method is not being utilized by the Corporation, then the Withholding Taxes shall be collected from Participant through a sale-to-cover transaction authorized by Participant, pursuant to which an immediate open-market sale of a portion of the shares of Common Stock issued to Participant will be effected, for and on behalf of Participant, by the Corporation's designated broker to cover the Withholding Tax liability estimated by the Corporation to be applicable to such issuance. Participant shall, promptly upon request from the Corporation, execute (whether manually or through electronic acceptance) an appropriate sales authorization (in form and substance reasonably satisfactory to the Corporation) that authorizes and directs the broker to effect such open-market, sale-to-cover transactions and remit the sale proceeds, net of brokerage fees and other applicable charges, to the Corporation in satisfaction of the applicable Withholding Taxes. However, no sale-to-cover transaction shall be effected unless (i) such a sale is at the time permissible under the Corporation's insider trading policies governing the sale of Common Stock and (ii) the transaction is not otherwise deemed to constitute a prohibited loan under Section 402 of the Sarbanes-Oxley Act of 2002.

(h)If the Corporation determines that such sale-to-cover transaction is not permissible or advisable at the time or if Participant otherwise fails to effect a timely sales authorization as required by this Agreement, then the Corporation may, in its sole discretion, elect either to defer the issuance of the shares of Common Stock until such sale-to-cover transaction can be effected in accordance with Participant's executed sale directive or to collect the applicable Withholding Taxes through a wire transfer of funds from Participant to the Corporation in the amount of such Withholding Taxes or by withholding such amount from other wages payable to Participant. In no event shall any shares of Common Stock be issued in the absence of an arrangement reasonably satisfactory to the Corporation for the satisfaction of the applicable Withholding Taxes, and any such arrangement must be in compliance with any applicable requirements of Code Section 409A.

(i)The Corporation shall collect the Withholding Taxes with respect to the phantom dividend equivalents distributed in a form other than shares of Common Stock by withholding a

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portion of that distribution equal to the amount of the applicable Withholding Taxes, with the cash portion of the distribution to be the first portion so withheld, or through such other tax withholding arrangement as the Corporation deems appropriate

(j)Notwithstanding the foregoing provisions of Paragraphs 7(d) through 7(h), the employee portion of the federal, state and local employment taxes required to be withheld by the Corporation in connection with the vesting of the shares of Common Stock or any other amounts hereunder (the “Employment Taxes”) shall in all events be collected from Participant no later than the last business day of the calendar year in which those shares or other amounts vest hereunder. Accordingly, to the extent the applicable issuance date for one or more vested shares of Common Stock or the distribution date for such other amounts is to occur in a year subsequent to the calendar year in which those shares or other amounts vest, Participant shall, on or before the last business day of the calendar year in which such shares or other amounts vest, deliver to the Corporation a check payable to its order (or a wire transfer of funds to the Corporation) in the dollar amount equal to the Employment Taxes required to be withheld with respect to those shares or other amounts. The provisions of this Paragraph 7(j) shall be applicable only to the extent necessary to comply with the applicable tax withholding requirements of Code Section 3121(v).

(k)Except as otherwise provided in Paragraph 5 or this Paragraph 7, the settlement of all Performance Shares or Performance-Qualified Shares which vest under the Award shall be made solely in shares of Common Stock.

8.Special Deferral Election. Provided Participant is a U.S. tax resident and subject to Participant's satisfaction of any applicable Withholding Tax obligations under Paragraph 7 and any other eligibility requirements established by the Administrator for a deferral election hereunder, Participant may elect to defer the issuance date of any shares of Common Stock which may become issuable to Participant pursuant to the terms of this Agreement, by submitting to the Corporation on a timely basis a deferral election in the form provided for such purpose. Such deferral election must be submitted to the Corporation prior to the last six (6) months of the Performance Period (including any abbreviated Performance Period) applicable to the shares for which the deferral election is made, and any deferral election submitted within that six (6)-month period or after the performance-based compensation subject to that election has become ascertainable shall have no force and effect. The deferral election must specify one or more deferred issuance dates or events that qualify as permissible distribution events under Code Section 409A and the Treasury Regulations thereunder. In submitting such deferral election, Participant must represent that he or she understands the effect of such deferral under relevant federal, state and local income and employment tax laws, including (without limitation) the fact that Social Security, Medicare and other taxes may be due upon the vesting of the shares of Common Stock notwithstanding the deferral election. In no event may such a deferral election be made after Participant's cessation of Continuous Service, and no deferral election shall have any force or effect unless such election complies with all applicable requirements of Code Section 409A and the Treasury Regulations thereunder.

9.Leaves of Absence. For purposes of applying the various Continuous Service vesting provisions of this Agreement, Participant shall be deemed to cease Continuous Service on the commencement date of any leave of absence and not to remain in Continuous Service status during the period of that leave, except to the extent otherwise required under employment laws in the jurisdiction where Participant is employed or pursuant to the following policy:

-    Participant shall be deemed to remain in Continuous Service status during (i) the first three (3) months of an approved personal leave of absence or (ii) the first seven (7) months of any bona fide leave of absence (other than an approved personal leave)

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and shall be deemed to cease Continuous Service upon the expiration of the applicable three (3)-month or seven (7)-month period.

-    In no event, however, shall Participant be deemed, for vesting purposes hereunder, to remain in Continuous Service beyond the earlier of (i) the expiration date of that leave of absence, unless Participant returns to active Continuous Service or Employee status on or before that date, or (ii) the date Participant's Continuous Service or Employee status actually terminates by reason of his or her voluntary or involuntary termination or by reason of his or her death or disability.

10.Compliance with Laws and Regulations. The issuance of shares of Common Stock pursuant to the Award shall be subject to compliance by the Corporation and Participant with all Applicable Laws relating thereto.

11.Notices. Any notice required to be given or delivered to the Corporation under the terms of this Agreement shall be in writing and addressed to the Corporation at its principal corporate offices. Any notice required to be given or delivered to Participant shall be in writing and addressed to Participant at the most current address then indicated for Participant on the Corporation's employee records or shall be delivered electronically to Participant through the Corporation's electronic mail system or through an on-line brokerage firm authorized by the Corporation to effect sales of the Common Stock issued hereunder. All notices shall be deemed effective upon personal delivery or delivery through the Corporation's electronic mail system or upon deposit in the U.S. mail, postage prepaid and properly addressed to the party to be notified.

12.Successors and Assigns. Except to the extent otherwise provided in this Agreement, the provisions of this Agreement shall inure to the benefit of, and be binding upon, the Corporation and its successors and assigns and Participant, Participant's assigns, the legal representatives, heirs and legatees of Participant's estate and any beneficiaries of the Award designated by Participant.

13.Code Section 409A

(a)It is the intention of the parties that the provisions of this Agreement shall, to the maximum extent permissible, comply with the requirements of the short-term deferral exception to Section 409A of the Code and Treasury Regulations Section 1.409A-1(b)(4) with respect to one or more shares of Common Stock underlying this Award. Accordingly, to the extent there is any ambiguity as to whether one or more provisions of this Agreement would otherwise contravene the requirements or limitations of Code Section 409A applicable to such short-term deferral exception, then those provisions, as they apply to such shares of Common Stock, shall be interpreted and applied in a manner that does not result in a violation of the requirements or limitations of Code Section 409A and the Treasury Regulations thereunder that apply to such exception.

(b)However, to the extent this Agreement should be deemed to create a deferred compensation arrangement subject to the requirements of Code Section 409A with respect to one or more shares of Common Stock underlying this Award, whether by reason of any deferral election made pursuant to Paragraph 8 above or the pro-rata service-vesting provisions of this Agreement, then the following provisions shall apply with respect to those shares, notwithstanding anything to the contrary set forth herein:

-    None of those shares of Common Stock or other amounts which become issuable or distributable with respect to those shares by reason of Participant's cessation of Continuous Service shall actually be issued or distributed to Participant until the date of

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Participant's Separation from Service or as soon thereafter as administratively practicable, but in no event later than the later of (i) the close of the calendar year in which such Separation from Service occurs or (ii) the fifteenth day of the third calendar month following the date of such Separation from Service.

-    None of those shares of Common Stock or other amounts which become issuable or distributable with respect to those shares by reason of Participant's cessation of Continuous Service shall actually be issued or distributed to Participant prior to the earlier of (i) the first day of the seventh (7th) month following the date of Participant's Separation from Service or (ii) the date of Participant's death, if Participant is deemed at the time of such Separation from Service to be a specified employee under Section 1.409A-1(i) of the Treasury Regulations issued under Code Section 409A, as determined by the Administrator in accordance with consistent and uniform standards applied to all other Code Section 409A arrangements of the Corporation, and such delayed commencement is otherwise required in order to avoid a prohibited distribution under Code Section 409A(a)(2). The deferred shares of Common Stock or other distributable amount shall be issued or distributed in a lump sum on the first day of the seventh (7th) month following the date of Participant's Separation from Service or, if earlier, the first day of the month immediately following the date the Corporation receives proof of Participant's death.

-    No amounts that vest and become payable under Paragraph 5 of this Agreement with respect to those shares of Common Stock by reason of a Change in Control shall be distributed to Participant at the time of such Change in Control, unless that transaction also constitutes a Qualifying Change in Control. In the absence of such a Qualifying Change in Control, the distribution shall not be made until the date on which the shares of Common Stock to which those amounts pertain would have become issuable in accordance with the provisions of Paragraph 7(a) of this Agreement.

-    If Participant has made a deferral election under Paragraph 8 of this Agreement with respect to any shares of Common Stock underlying this Award, no amounts that vest and become payable under Paragraph 5 with respect to those shares by reason of a Change in Control shall be distributed to Participant at the time of that Change in Control unless (i) the transaction also constitutes a Qualifying Change in Control and (ii) such deferral election provides for a distribution upon such an event. In the absence of such a Qualifying Change in Control or distribution election tied thereto, the distribution shall not be made until the date on which the shares of Common Stock to which those amounts pertain would have become issuable in accordance with Participant's deferral election under Paragraph 8 of this Agreement.

14.Construction. This Agreement and the Award evidenced hereby are made and granted pursuant to the Plan and are in all respects limited by and subject to the terms of the Plan. In the event of any conflict between the provisions of this Agreement and the terms of the Plan, the terms of the Plan shall be controlling. All decisions of the Administrator with respect to any question or issue arising under the Plan or this Agreement shall be conclusive and binding on all persons having an interest in the Award.

15.Governing Law/Venue. The interpretation, performance and enforcement of this Agreement shall be governed by the laws of the State of Delaware without resort to that State's conflict-of-laws rules. For purposes of any action, lawsuit or other proceedings brought to enforce this Agreement or otherwise relating to or arising from this Agreement, the parties hereby submit to and consent to the sole and exclusive jurisdiction of the courts of San Mateo County, California, or the federal courts for the United

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States for the Northern District of California, and no other courts, where this grant is made and/or to be performed.

16.Employment at Will. Nothing in this Agreement or in the Plan shall confer upon Participant any right to remain in Continuous Service for any period of specific duration or interfere with or otherwise restrict in any way the rights of the Corporation (or any Related Entity employing or retaining Participant) or of Participant, which rights are hereby expressly reserved by each, to terminate Participant's Continuous Service at any time for any reason, with or without Cause.

17.Severability. The provisions of this Agreement are severable and if any one or more provisions are determined to be illegal or otherwise unenforceable, in whole or in part, the remaining provisions shall nevertheless be binding and enforceable.

18.Waiver. Participant acknowledges that a waiver by the Corporation of breach of any provision of this Agreement shall not operate or be construed as a waiver of any other provision of this Agreement, or of any subsequent breach of this Agreement.

19.ElectronicDeliveryandAcceptance. The Corporation may, in its sole discretion, decide to deliver any documents related to current or future participation in the Plan by electronic means. Participant hereby consents to receive such documents by electronic delivery and agrees to participate in the Plan through an on-line or electronic system established and maintained by the Corporation or a third party designated by the Corporation.

20.Plan Prospectus. The official prospectus for the Plan is available on the Corporation's intranet at: http://gnet/ HR/stocks_new.asp. Participant may also obtain a printed copy of the prospectus by contacting Stock Plan Services at stockplanservices@gilead.com.

21.Participant Acceptance. Participant must accept the terms and conditions of this Agreement either electronically through the electronic acceptance procedure established by the Corporation or through a written acceptance delivered to the Corporation in a form satisfactory to the Corporation. In no event shall any shares of Common Stock be issued (or other securities or property distributed) under this Agreement in the absence of such acceptance.

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IN WITNESS WHEREOF, Gilead Sciences, Inc. has caused this Agreement to be executed on its behalf by its duly-authorized officer on the day and year first indicated above.

GILEAD SCIENCES, INC.

By:

Title:

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APPENDIX A

DEFINITIONS

The following definitions shall be in effect under the Agreement:

A.Administrator shall mean the Compensation Committee of the Board acting in its capacity as administrator of the Plan.

B.Agreement shall mean this Performance Share Award Agreement.

C.Applicable Lawsshall mean the legal requirements related to the Plan and the Award under applicable provisions of the federal securities laws, state corporate and securities laws, the Code, the rules of any applicable Stock Exchange on which the Common Stock is listed for trading, and the rules of any non-U.S. jurisdiction applicable to Awards granted to residents therein.

D.Award shall mean the award of Performance Shares made to Participant pursuant to the terms of this Agreement.

E.Award Date shall mean the date the Performance Shares are awarded to Participant pursuant to the Agreement and shall be the date indicated in Paragraph 1 of the Agreement.

F.Board shall mean the Corporation's Board of Directors.

G.Causeshall have the meaning assigned to such term in Section 11(c) of the Plan.

H.Change in Control shall mean a change in ownership or control of the Corporation effected through the consummation of any of the following transactions:

(i)a merger, consolidation or other reorganization approved by the Corporation's stockholders, unless securities representing more than fifty percent (50%) of the total combined voting power of the voting securities of the successor corporation are immediately thereafter beneficially owned, directly or indirectly and in substantially the same proportion, by the persons who beneficially owned the Corporation's outstanding voting securities immediately prior to such transaction;

(ii)a sale, transfer or other disposition of all or substantially all of the Corporation's assets;

(iii)the closing of any transaction or series of related transactions pursuant to which any person or any group of persons comprising a “group” within the meaning of Rule 13d-5(b)(1) of the 1934 Act (other than the Corporation or a person that, prior to such transaction or series of related transactions, directly or indirectly controls, is controlled by or is under common control with, the Corporation) becomes directly or indirectly (whether as a result of a single acquisition or by reason of one or more acquisitions within the twelve (12)-month period ending with the most recent acquisition) the beneficial owner (within the meaning of Rule 13d-3 of the 1934 Act) of securities possessing (or convertible into or exercisable for securities possessing) more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities (as measured in terms of the power

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to vote with respect to the election of Board members) outstanding immediately after the consummation of such transaction or series of related transactions, whether such transaction involves a direct issuance from the Corporation or the acquisition of outstanding securities held by one or more of the Corporation's existing stockholders; or

(iv)a change in the composition of the Board over a period of twelve (12) consecutive months or less such that a majority of the Board members ceases, by reason of one or more contested elections for Board membership, to be comprised of individuals who either (A) have been Board members continuously since the beginning of such period or (B) have been elected or nominated for election as Board members during such period by at least a majority of the Board members described in clause (A) who were still in office at the time the Board approved such election or nomination.

In no event, however, shall a Change in Control be deemed to occur upon a merger, consolidation or other reorganization effected primarily to change the State of the Corporation's incorporation or to create a holding company structure pursuant to which the Corporation becomes a wholly-owned subsidiary of an entity whose outstanding voting securities immediately after its formation are beneficially owned, directly or indirectly and in substantially the same proportion, by the persons who beneficially owned the Corporation's outstanding voting securities immediately prior to the formation of such entity. Should such holding company structure or other Parent entity be established for the Corporation, then subparagraph (iv) shall be applied solely to the board of directors of that holding company or Parent entity.

I.    Code shall mean the Internal Revenue Code of 1986, as amended.

J.    Common Stock shall mean shares of the Corporation's common stock.

K.    Constructive Termination shall have the meaning assigned to such term in Section 11(d) of the Plan.

L.    Consultant shall mean any person, including an advisor, who is compensated by the Corporation or any Related Entity for services performed as a non-employee consultant; provided, however, that the term “Consultant” shall not include non-employee Directors serving in their capacity as Board members. The term “Consultant” shall include a member of the board of directors of a Related Entity.

Continuous Service shall mean the performance of services for the Corporation or a Related Entity (whether now existing or subsequently established) by a person in the capacity of an Employee, Director or Consultant. For purposes of this Agreement, Participant shall be deemed to cease Continuous Service immediately upon the occurrence of either of the following events: (i) Participant no longer performs services in any of the foregoing capacities for the Corporation or any Related Entity or (ii) the entity for which Participant is performing such services ceases to remain a Related Entity of the Corporation, even though Participant may subsequently continue to perform services for that entity. The Administrator shall have the exclusive discretion to determine when Participant ceases Continuous Service for purposes of the Award.

M.    Corporation shall mean Gilead Sciences, Inc., a Delaware corporation, and any successor corporation to all or substantially all of the assets or voting stock of Gilead Sciences, Inc. which shall by appropriate action adopt the Plan.

N.    Director shall mean a member of the Board.

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O.    Employee shall mean an individual who is in the employ of the Corporation (or any Related Entity), subject to the control and direction of the employer entity as to both the work to be performed and the manner and method of performance.

P.    Employer shall mean the Corporation or any Related Entity employing Participant.

Q.    Fair Market Valueper share of Common Stock on any relevant date shall be the closing price per share of Common Stock (or the closing bid, if no sales were reported) on that date, as quoted on the Stock Exchange that is at the time serving as the primary trading market for the Common Stock; provided, however, that if there is no reported closing price or closing bid for that date, then the closing price or closing bid, as applicable, for the last trading date on which such closing price or closing bid was quoted shall be determinative of such Fair Market Value. The applicable quoted price shall be as reported in The Wall Street Journal or such other source as the Administrator deems reliable.

R.    1934 Act shall mean the Securities Exchange Act of 1934, as amended from time to time.

S.    Participant shall mean the person to whom the Award is made pursuant to the Agreement.

T.    Parent shall mean any corporation (other than the Corporation) in an unbroken chain of corporations ending with the Corporation, provided each corporation in the unbroken chain (other than the Corporation) owns, at the time of the determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain.

U.    Performance Goal shall mean the total shareholder return performance goal specified on attached Schedule I (the “TSR Performance Goal”) that must be attained in order to satisfy the performance-vesting requirement for the shares of Common Stock subject to this Award.

V.    Performance Period shall mean the period specified on attached Schedule I over which the attainment of the TSR Performance Goal is to be measured.

W.    Performance-Qualified Shares shall mean the maximum number of Shares in which Participant can vest based on the level at which the Performance Goal for the Performance Period is attained and shall be calculated in accordance with the provisions of attached Schedule I. In no event shall the number of such Performance-Qualified Shares exceed two hundred percent (200%) of the designated number of Performance Shares set forth in the Performance Shares section of Paragraph 1 of this Agreement. Each Performance-Qualified Share that vests pursuant to the terms of the Award shall entitle Participant to receive one share of Common Stock.

X.    Performance Shares shall mean the number of phantom shares of Common Stock awarded under this Agreement that shall be applied to the calculation of the maximum number of Performance-Qualified Shares (if any) based on the level at which the Performance Goal is in fact attained over the applicable Performance Period.

Y.    Permanent Disability shall mean the inability of Participant to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment expected to result in death or to be of continuous duration of twelve (12) months or more.

Z.    Plan shall mean the Corporation's 2004 Equity Incentive Plan, as amended.

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AA.    Qualifying Change in Control shall mean a change in control of ownership of the Corporation effected by one or more of the following transactions:

(i)a merger or consolidation in which the Corporation is not the surviving entity and in which one person or a group of related persons (other than the Corporation or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation) acquires ownership of securities possessing more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities or constituting more than fifty percent (50%) of the total fair market value of the Corporation's outstanding securities;

(ii)the sale, transfer or other disposition of all or substantially all of the assets of the Corporation in complete liquidation or dissolution of the Corporation;

(iii)any reverse merger in which the Corporation is the surviving entity but in which one person or a group of related persons (other than the Corporation or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation) acquires ownership of securities possessing more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities or constituting more than fifty percent (50%) of the total fair market value of the Corporation's outstanding securities;

(iv)the acquisition, directly or indirectly, by any person or related group of persons (other than the Corporation or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation) of beneficial ownership of securities possessing more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities or constituting more than fifty percent (50%) of the total fair market value of the Corporation's outstanding securities pursuant to a tender or exchange offer made directly to the Corporation's stockholders; or

(v)a change in the composition of the Board over a period of twelve (12) consecutive months or less such that a majority of the Board members ceases, by reason of one or more contested elections for Board membership, to be comprised of individuals who either (A) have been Board members continuously since the beginning of such period or (B) have been elected or nominated for election as Board members during such period by at least a majority of the Board members described in clause (A) who were still in office at the time the Board approved such election or nomination.

The foregoing definition of Qualifying Change in Control shall in all instances be applied and interpreted in such manner that the applicable Qualifying Change in Control transaction that serves as an issuance event for the shares of Common Stock subject to this Award (or distribution event for any amounts relating to those shares) that vest upon the occurrence of a Change in Control and are otherwise at the time subject to the issuance or distribution restrictions of Code Section 409A will also qualify as: (i) a change in the ownership of the Corporation, as determined in accordance with Section 1.409A-3(i)(5)(v) of the Treasury Regulations, (ii) a change in the effective control of the Corporation, as determined in accordance with Section 1.409A-3(i)(5)(vi) of the Treasury Regulations, or (iii) a change in the ownership of a substantial portion of the assets of the Corporation, as determined in accordance with Section 1.409A-3(i)(5)(vii) of the Treasury Regulations.

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BB.    Related Entity shall mean (i) any Parent or Subsidiary of the Corporation and (ii) any corporation in an unbroken chain of corporations beginning with the Corporation and ending with the corporation in the chain for which Participant provides services as an Employee, Director or Consultant, provided each corporation in such chain owns securities representing at least fifty percent (50%) of the total outstanding voting power of the outstanding securities of another corporation or entity in such chain.

CC.    Retirement shall mean Participant's cessation of Employee status on or after the date on which his or her combined age and years of Continuous Service equal or exceed seventy (70) years.

DD.    Separation from Service shall mean Participant's cessation of Employee status by reason of his or her death, retirement or termination of employment. Participant shall be deemed to have terminated employment for such purpose at such time as the level of his or her bona fide services to be performed as an Employee (or as a consultant or independent contractor) permanently decreases to a level that is not more than twenty percent (20%) of the average level of services he or she rendered as an Employee during the immediately preceding thirty-six (36) months (or such shorter period for which he or she may have rendered such services). Solely for purposes of determining when a Separation from Service occurs, Participant will be deemed to continue in “Employee” status for so long as he or she remains in the employ of one or more members of the Employer Group, subject to the control and direction of the employer entity as to both the work to be performed and the manner and method of performance. “Employer Group” means the Corporation and any Parent or Subsidiary and any other corporation or business controlled by, controlling or under common control with, the Corporation, as determined in accordance with Sections 414(b) and (c) of the Code and the Treasury Regulations thereunder, except that in applying Sections 1563(1), (2) and (3) of the Code for purposes of determining the controlled group of corporations under Section 414(b), the phrase “at least 50 percent” shall be used instead of “at least 80 percent” each place the latter phrase appears in such sections and in applying Section 1.414(c)-2 of the Treasury Regulations for purposes of determining trades or businesses that are under common control for purposes of Section 414(c), the phrase “at least 50 percent” shall be used instead of “at least 80 percent” each place the latter phrase appears in Section 1.414(c)-2 of the Treasury Regulations. Any such determination as to Separation from Service, however, shall be made in accordance with the applicable standards of the Treasury Regulations issued under Section 409A of the Code.

EE.    Stock Exchange shall mean the American Stock Exchange, the Nasdaq Global or Global Select Market or the New York Stock Exchange.

FF.    Subsidiary shall mean any corporation (other than the Corporation) in an unbroken chain of corporations beginning with the Corporation, provided each corporation (other than the last corporation) in the unbroken chain owns, at the time of the determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain.

GG.    Withholding Taxes shall mean the federal, state and local income taxes and the employee portion of the federal, state and local employment taxes required to be withheld by the Corporation in connection with the vesting and issuance of the shares of Common Stock which vest under of the Award, any phantom dividend equivalents distributed with respect to those shares and any other amounts distributable in replacement or substitution of such shares.

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SCHEDULE I

PERFORMANCE GOAL AND PERFORMANCE PERIOD

PERFORMANCE PERIOD

The measurement period for the Performance Shares shall be the three (3)-year period beginning February 1, 2013 and ending January 31, 2016 (the “Performance Period”).

PERFORMANCE GOAL FOR PERFORMANCE VESTING

Performance Goal - Total Shareholder Return: The performance-vesting requirement for the Performance Shares subject to this Award shall be tied to the percentile level at which the total shareholder return (including stock price appreciation and reinvestment of any cash dividends or other stockholder distributions) to the Corporation's stockholders over the Performance Period stands in relation to the total shareholder return realized for that period by the companies comprising the following three subsets of the S&P Healthcare Index: Biotechnology, Pharmaceuticals and Health Care Equipment (collectively the “S&P Healthcare Sub-Index”).

For such purpose, the total shareholder return (“TSR”) shall be determined pursuant to the following formula:

TSR = (Ending Stock Price* - Beginning Stock Price**) + Reinvested Dividends***                     Beginning Stock Price**

* Ending Stock Price is the average daily closing price per share of the Common Stock calculated for the last sixty (60) consecutive trading days within the Performance Period.

** Beginning Stock Price is the average daily closing price per share of the Common Stock calculated for the first sixty (60) consecutive trading days within the Performance Period.

*** Reinvested Dividends shall be calculated by multiplying (i) the aggregate number of shares (including fractional shares) that could have been purchased during the Performance Period had each cash dividend paid on a single share during that period been immediately reinvested in additional shares (or fractional shares) at the closing selling price per share of the Common Stock on the applicable dividend payment date by (ii) the average daily closing price per share calculated for the last sixty (60) consecutive trading days within the Performance Period.

Each of the foregoing amounts shall be equitably adjusted for stock splits, stock dividends, recapitalizations and other similar events affecting the shares in question without the issuer's receipt of consideration.

For each company in the S&P Healthcare Sub-Index, the TSR with respect to its common stock shall be calculated in the same manner as for the Common Stock.

Should a Change in Control occur during the Performance Period, then the attained level of the Performance Goal shall be determined in accordance with the applicable Change in Control provisions of Paragraph 5 of this Agreement.

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Performance-Qualified Shares: Within thirty-five (35) days after the completion of the Performance Period, the Administrator shall determine and certify the actual level at which the TSR Performance Goal is attained. The actual number of Performance-Qualified Shares that results from such certification (the “Performance-Qualified Shares”) may range from 0% to 200% of the number of Performance Shares subject to this Award, with the actual percentage to be determined on the basis of the percentile level at which the Administrator certifies that the TSR Performance Goal has been attained in relation to the total shareholder return realized for that period by the companies comprising the S&P Healthcare Sub-Index; provided, however, that (i) the maximum number of shares of Common Stock that may qualify as Performance-Qualified Shares may not exceed 200% of the number of Performance Shares subject to this Award in accordance with Paragraph 1 of this Agreement and (ii) in no event shall the number of shares of Common Stock that may qualify as Performance-Qualified Shares pursuant to the Relative TSR Payout Slope below exceed 100% of the number of Performance Shares subject to this Award if the Corporation's absolute TSR for the Performance Period is negative.

Payout Slope for Determining Number of Performance-Qualified Shares Based on Attained Levels of TSR Performance Goal: The number of shares of Common Stock that may qualify as Performance-Qualified Shares on the basis of the certified percentile level of TSR Performance Goal attainment shall be calculated by multiplying the number of Performance Shares subject to this Award in accordance with Paragraph 1 of this Agreement by the applicable percentage determined in accordance with the following payout slope for the TSR Performance Goal (with appropriate straight-line interpolation for any attained percentile level within two designated percentile levels in such slope):

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EX-10.50

Exhibit 10.50

REVENUE PERFORMANCE GOAL

GILEAD SCIENCES, INC.

PERFORMANCE SHARE AWARD AGREEMENT

RECITALS

A.    The Corporation has implemented the Plan for the purpose of providing incentives to attract, retain and motivate eligible Employees, Directors and Consultants to continue their service relationship with the Corporation.

B.    Participant is to render valuable services to the Corporation (or a Related Entity), and this Agreement is executed pursuant to, and is intended to carry out the purposes of, the Plan in connection with the Corporation's issuance of shares of Common Stock to Participant thereunder.

C.    All capitalized terms in this Agreement shall have the meaning assigned to them herein or in the attached Appendix A.

NOW, THEREFORE, it is hereby agreed as follows:

1.Grant of Performance Shares. The Corporation hereby awards to Participant, as of the Award Date indicated below, an award (the “Award”) of Performance Shares under the Corporation's 2004 Equity Incentive Plan, as amended (the “Plan”). Each Performance Share which vests pursuant to the terms of this Agreement shall provide Participant with the right to receive one or more shares of Common Stock on the designated issuance date for those shares. The number of Performance Shares subject to this Award. the applicable performance-vesting and service-vesting requirements for each separate Tranche of those Performance Shares, the date or dates on which the shares of Common Stock that vest hereunder shall become issuable and the remaining terms and conditions governing the Award, including the applicable vesting acceleration provisions, shall be as set forth in this Agreement.

AWARD SUMMARY

Participant	[FIRST NAME MIDDLE NAME LAST NAME]
Award Date:	[GRANT DATE]
Designated Number of Performance Shares:	The actual number of shares of Common Stock that may become issuable pursuant to the Performance Shares awarded under this Agreement shall be determined in accordance with the performance-vesting and service-vesting provisions of attached Schedule I. For purposes of the applicable calculations under Schedule I, the total designated number of Performance Shares to be utilized is [SHARES] shares (the” Performance Shares”).
	The Performance Shares shall be divided into three separate Tranches, and one third of the total number of Performance Shares shall be allocated to each such Tranche.

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Vesting Schedule:

Normal Vesting. Each Tranche of Performance Shares shall be subject to the performance-vesting and service-vesting requirements set forth for that particular Tranche in attached Schedule I. Change in Control Vesting. The shares of Common Stock underlying each Tranche of Performance Shares may also vest on an accelerated basis in accordance with the applicable provisions of Paragraph 4 of this Agreement should a Change in Control occur after the start but prior to the completion of the Performance Period or Service Period applicable to that particular Tranche.

Issuance Date:

The shares of Common Stock which actually vest and become issuable pursuant to each Tranche of Performance Shares shall be issued in accordance with the provisions of this Agreement applicable to the particular circumstances under which such vesting occurs.

2.Limited Transferability. Prior to the actual issuance of the shares of Common Stock which vest hereunder, Participant may not transfer any interest in the Performance Shares subject to this Award or the underlying shares of Common Stock or pledge or otherwise hedge the sale of those Performance Shares or underlying shares, including (without limitation) any short sale or any acquisition or disposition of any put or call option or other instrument tied to the value of the underlying shares of Common Stock. However, any shares of Common Stock which vest hereunder but otherwise remain unissued at the time of Participant's death may be transferred pursuant to the provisions of Participant's will or the laws of inheritance or to Participant's designated beneficiary or beneficiaries of this Award. Participant may also direct the Corporation to record the ownership of any shares of Common Stock which in fact vest and become issuable hereunder in the name of a revocable living trust established for the exclusive benefit of Participant or Participant and his or her spouse. Participant may make such a beneficiary designation or ownership directive at any time by completing the Corporation's Universal Beneficiary Designation form and filing the completed form with the Plan Administrator or its designee.

3.Stockholder Rights and Dividend Equivalents

(a)The holder of this Award shall not have any stockholder rights, including voting, dividend or liquidation rights, with respect to the shares of Common Stock subject to the Award until Participant becomes the record holder of those shares upon their actual issuance following the Corporation's collection of the applicable Withholding Taxes. Notwithstanding the foregoing, should any dividend or other distribution, whether regular or extraordinary and whether payable in cash, securities (other than Common Stock) or other property, be declared and paid on the outstanding Common Stock while one or more Performance Shares remain subject to this Award (i.e., the underlying shares of Common Stock are not otherwise issued and outstanding for purposes of entitlement to the dividend or distribution), then a special book account shall be established for Participant and credited with a phantom dividend equivalent to the actual dividend or distribution that would have been paid on the maximum number of shares of Common Stock that can qualify as Performance-Qualified Shares under this Award, had that number of shares been issued and outstanding and entitled to that dividend or distribution. As one or more shares of Common Stock subsequently vest hereunder upon the satisfaction of the applicable vesting requirements for those shares, the phantom dividend equivalents credited to those particular shares in the book account shall vest, and those vested dividend equivalents shall be distributed to Participant (in the same form the actual dividend or distribution was paid to the holders of the Common Stock entitled to that dividend or distribution or in such other form as the Administrator deems appropriate under the circumstances) concurrently with the issuance of those vested shares. However, such distribution shall be subject to the Corporation's collection of the Withholding Taxes applicable to that distribution. To the extent any phantom dividend equivalents are to be distributed in shares of Common Stock, the following conversion process will be in effect.  For each such

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dividend or distribution that is to be converted into shares of Common Stock, the aggregate dollar value of the cash, securities or other property that would have been paid as an actual dividend or distribution on the shares of Common Stock subject to this Award had they been actually issued and outstanding shares at the time of such dividend or distribution will be divided by the Fair Market Value per share of Common Stock measured as of the date on which such dividend or distribution was paid on the outstanding Common Stock, with any fractional share of Common Stock rounded down to the next whole share of Common Stock.  The Administrator shall have the sole discretion to determine the dollar value of any such dividend or distribution paid other than in the form of cash, and its determination shall be controlling.  

(b)To the extent the maximum number of shares of Common Stock that can qualify as Performance-Qualified Shares under any Tranche of this Award is not in fact earned by reason of the level at which the Performance Goal applicable to that Tranche is actually attained, then the phantom dividend equivalents credited to those unearned shares shall be cancelled, and Participant shall cease to have any right or entitlement to receive any distributions or other amounts with respect to those cancelled dividend equivalents.

(c)Should Participant cease Continuous Service without vesting in one or more of the shares of Common Stock subject to this Award (including any shares which do not otherwise vest at that time after taking into account any applicable vesting acceleration provisions set forth in this Agreement and the attached Schedule I), then the phantom dividend equivalents credited to those unvested shares shall be cancelled, and Participant shall thereupon cease to have any further right or entitlement to those cancelled amounts.

4.Change in Control. The following provisions shall apply only to the extent a Change in Control is consummated prior to the completion of the one or more separate Service Periods that are in effect at the time of such Change in Control with respect to the individual Tranches into which the Performance Shares are divided in accordance with the provisions of Paragraph 1 of this Agreement and attached Schedule I:

(a)Should (i) the Change in Control occur during a Performance Period that is in effect at the time with respect to a particular Tranche of Performance Shares but prior to the completion of that Performance Period and (ii) Participant remain in Continuous Service through the effective date of that Change in Control, then Participant shall immediately vest in that number of shares of Common Stock equal to the designated number of Performance Shares allocated to that particular Tranche in accordance with Paragraph 1 of this Agreement and the provisions of attached Schedule I, without any measurement of Performance Goal attainment to date with respect to that particular Tranche. To the extent a Performance Period for a particular Tranche of Performance Shares has not commenced prior to the effective date of the Change in Control, the Performance Shares allocated to that Tranche in accordance with Paragraph 1 of this Agreement and the provisions of attached Schedule I shall be cancelled, and Participant shall not have any further right or entitlement to receive any shares of Common Stock with respect to those cancelled Performance Shares.

(b)Should (i) the Change in Control occur at any time on or after the completion of the Performance Period applicable to a particular Tranche of Performance Shares but prior to the completion of the Service Period specified for that Tranche in attached Schedule I and (ii) Participant remain in Continuous Service through the effective date of that Change in Control, then Participant shall immediately vest in the number of shares of Common Stock equal to the number of Performance-Qualified Shares (if any) at the time subject to that Tranche by reason of the level at which the Revenue Performance Goal for that Tranche was in fact attained for the Performance Period applicable to that Tranche.

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(c)Subparagraphs (a) and (b) of this Paragraph 4 shall also apply should Participant's Continuous Service terminate, by reason of an involuntary termination other than for Cause or his or her resignation due to Constructive Termination, at any time during the period beginning with the execution date of the definitive agreement for the Change in Control transaction and ending with the earlier of (i) the effective date of that Change in Control or (ii) the termination of the definitive agreement without the consummation of the Change in Control; provided, however, that in no event shall Participant become entitled to any shares of Common Stock pursuant to this Paragraph 4 if the Change in Control is not in fact consummated.

(d)Should Participant cease Continuous Service by reason of Retirement, death or Permanent Disability during one or more Service Periods that are, pursuant to the provisions of attached Schedule I, in effect at that time with respect to one or more Tranches of Performance Shares and a Change in Control subsequently occur prior to the completion of each such applicable Service Period, then Participant shall, at the time of such Change in Control, vest in a pro-rated number of shares of Common Stock calculated by multiplying (i) the number of Performance Shares or Performance-Qualified Shares (if any) determined for each such Tranche in accordance with the applicable provisions of subparagraphs (a) and (b) of this Paragraph 4 by (ii) a fraction, the numerator of which is the number of months of Continuous Service actually completed by Participant in the applicable Service Period for such Tranche (rounded to the closest whole month), and the denominator of which is the number of months (rounded to the closest whole number) comprising the portion of that Service Period ending with the effective date of the Change in Control.

(e)The number of shares of Common Stock in which Participant vests on the basis of the Performance Shares or Performance-Qualified Shares determined in accordance with the foregoing provisions of this Paragraph 4 shall be converted into the right to receive for each such share the same consideration per share of Common Stock payable to the other stockholders of the Corporation in consummation of the Change in Control, and such consideration shall be distributed to Participant on the earlier of (i) the tenth (10th) business day following the effective date of the Change in Control, provided such Change in Control also constitutes a Qualifying Change in Control, or (ii) the date those shares would have been issued to Participant in accordance with Paragraph 6 in the absence of such Change in Control, unless a later issuance date is in effect for those shares pursuant to any deferral election made by Participant pursuant to Paragraph 7. Each issuance or distribution made under this Paragraph 4(e) shall be subject to the Corporation's collection of the applicable Withholding Taxes.

(f)Except for the actual number of shares of Common Stock in which Participant vests in accordance with this Paragraph 4, Participant shall cease to have any further right or entitlement to any additional shares of Common Stock under this Agreement following the effective date of the Change in Control.

5.Adjustment in Shares. Should any change be made to the Common Stock by reason of any stock split, stock dividend, recapitalization, combination of shares, exchange of shares, spin-off transaction, extraordinary dividend or distribution or other change affecting the outstanding Common Stock as a class without the Corporation's receipt of consideration, or should the value of the outstanding shares of Common Stock be substantially reduced as a result of a spin-off transaction or an extraordinary dividend or distribution, or should there occur any merger, consolidation or other reorganization, then equitable adjustments shall be made by the Administrator to the total number and/or class of securities issuable pursuant to this Award in order to reflect such change. In making such equitable adjustments, the Administrator shall take into account any amounts credited to Participant's book account under Paragraph 3(a) in connection with the transaction, and the determination of the Administrator shall be final, binding and conclusive. In the event of any Change in Control transaction, the provisions of Paragraph 4 shall be controlling.

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6.Issuance or Distribution of Vested Shares or Other Amounts.

(a)Except as otherwise provided in Paragraph 4 or Paragraph 7, the shares of Common Stock in which Participant vests pursuant to the performance-vesting and Continuous Service vesting provisions of attached Schedule I shall be issued in accordance with the following provisions:

-    The shares of Common Stock underlying each particular Tranche of Performance Shares shall be effected during the period beginning with the first business day of the calendar year immediately succeeding the end of the Service Period specified for that Tranche in attached Schedule I and ending no later than March 15 of that calendar year.

(b)The Corporation shall, on the applicable issuance date, issue to or on behalf of Participant a certificate in electronic form for the shares of Common Stock in which Participant vests pursuant to the performance-vesting and Continuous Service vesting provisions of attached Schedule I and shall concurrently distribute to Participant any phantom dividend equivalents with respect to those Shares. In lieu of such electronic delivery of the shares, Participant may request actual stock certificates for those shares.

(c)Except as otherwise provided in Paragraph 4, no shares of Common Stock shall be issued prior to the completion of the Service Period applicable to those shares. No fractional shares of Common Stock shall be issued pursuant to this Award, and any fractional share resulting from any calculation made in accordance with the terms of this Agreement shall be rounded down to the next whole share.

(d)Regardless of any action the Corporation and/or the Employer take with respect to any or all Withholding Taxes related to Participant's participation in the Plan and legally applicable to Participant, Participant acknowledges that the ultimate liability for all Withholding Taxes is and remains Participant's responsibility and may exceed the amount actually withheld by the Corporation or the Employer. Participant further acknowledges that the Corporation and/or the Employer (i) make no representations or undertakings regarding the treatment of any Withholding Taxes in connection with any aspect of the Award, including the grant, vesting or settlement of the Award, the issuance of shares of Common Stock or other property in settlement of the Award, the subsequent sale of the shares of Common Stock acquired pursuant to such issuance and the receipt of any dividends and/or phantom dividend equivalents and (ii) do not commit to, and are under no obligation to, structure the terms of the grant or any aspect of the Award to reduce or eliminate Participant's liability for Withholding Taxes or achieve any particular tax result. Further, if Participant has become subject to Withholding Taxes in more than one jurisdiction between the Award Date and the date of any relevant taxable or tax withholding event (as applicable), Participant acknowledges that the Corporation and/or the Employer (or former employer, as applicable) may be required to withhold or account for Withholding Taxes in more than one jurisdiction.

(e)The Corporation shall collect, and Participant hereby authorizes the Corporation to collect, the Withholding Taxes with respect to the shares of Common Stock issued under this Agreement (including shares of Common Stock issued in settlement of phantom dividend equivalents) through an automatic share withholding procedure pursuant to which the Corporation will withhold, immediately as the shares of Common Stock are issued under the Award, a portion of those shares with a Fair Market Value (measured as of the issuance date) equal to the amount of such Withholding Taxes (the “Share Withholding Method”). Notwithstanding the foregoing, the Share Withholding Method shall not be utilized if (i) such method is not permissible or advisable under local law or (ii) the Corporation otherwise decides no longer to utilize such method and provides Participant with notice to such effect.

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(f)If the Share Withholding Method is to be utilized for the collection of Withholding Taxes, then the Corporation shall withhold the number of otherwise issuable shares of Common Stock necessary to satisfy the applicable Withholding Taxes based on the applicable minimum statutory rate or other applicable withholding rate. If the obligation for Withholding Taxes is satisfied by using the Share Withholding Method, then Participant will, for tax purposes, be deemed to have been issued the full number of shares of Common Stock subject to the vested Award, notwithstanding that a number of shares of Common Stock are withheld solely for the purpose of paying the applicable Withholding Taxes.

(g)The Corporation shall have sole discretion to determine whether or not the Share Withholding Method shall be utilized for the collection of the applicable Withholding Taxes. Participant shall be notified (in writing or through the Corporation's electronic mail system) in the event the Corporation no longer intends to utilize the Share Withholding Method. Should any shares of Common Stock become issuable under the Award (including shares of Common Stock issued in settlement of phantom dividend equivalents) at a time when the Share Withholding Method is not being utilized by the Corporation, then the Withholding Taxes shall be collected from Participant through a sale-to-cover transaction authorized by Participant, pursuant to which an immediate open-market sale of a portion of the shares of Common Stock issued to Participant will be effected, for and on behalf of Participant, by the Corporation's designated broker to cover the Withholding Tax liability estimated by the Corporation to be applicable to such issuance. Participant shall, promptly upon request from the Corporation, execute (whether manually or through electronic acceptance) an appropriate sales authorization (in form and substance reasonably satisfactory to the Corporation) that authorizes and directs the broker to effect such open-market, sale-to-cover transactions and remit the sale proceeds, net of brokerage fees and other applicable charges, to the Corporation in satisfaction of the applicable Withholding Taxes. However, no sale-to-cover transaction shall be effected unless (i) such a sale is at the time permissible under the Corporation's insider trading policies governing the sale of Common Stock and (ii) the transaction is not otherwise deemed to constitute a prohibited loan under Section 402 of the Sarbanes-Oxley Act of 2002.

(h)If the Corporation determines that such sale-to-cover transaction is not permissible or advisable at the time or if Participant otherwise fails to effect a timely sales authorization as required by this Agreement, then the Corporation may, in its sole discretion, elect either to defer the issuance of the shares of Common Stock until such sale-to-cover transaction can be effected in accordance with Participant's executed sale directive or to collect the applicable Withholding Taxes through a wire transfer of funds from Participant to the Corporation in the amount of such Withholding Taxes or by withholding such amount from other wages payable to Participant. In no event shall any shares of Common Stock be issued in the absence of an arrangement reasonably satisfactory to the Corporation for the satisfaction of the applicable Withholding Taxes, and any such arrangement must be in compliance with any applicable requirements of Code Section 409A.

(i)The Corporation shall collect the Withholding Taxes with respect to the phantom dividend equivalents distributed in a form other than shares of Common Stock by withholding a portion of that distribution equal to the amount of the applicable Withholding Taxes, with the cash portion of the distribution to be the first portion so withheld, or through such other tax withholding arrangement as the Corporation deems appropriate

(j)Notwithstanding the foregoing provisions of Paragraphs 6(d) through 6(h), the employee portion of the federal, state and local employment taxes required to be withheld by the Corporation in connection with the vesting of the shares of Common Stock or any other amounts hereunder (the “Employment Taxes”) shall in all events be collected from Participant no later than the last business day of the calendar year in which those shares or other amounts vest hereunder. Accordingly, to the extent the applicable issuance date for one or more vested shares of Common Stock or the distribution date for such

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other amounts is to occur in a year subsequent to the calendar year in which those shares or other amounts vest, Participant shall, on or before the last business day of the calendar year in which such shares or other amounts vest, deliver to the Corporation a check payable to its order (or a wire transfer of funds to the Corporation) in the dollar amount equal to the Employment Taxes required to be withheld with respect to those shares or other amounts. The provisions of this Paragraph 6(j) shall be applicable only to the extent necessary to comply with the applicable tax withholding requirements of Code Section 3121(v).

(k)Except as otherwise provided in Paragraph 4 or this Paragraph 6, the settlement of all Performance Shares or Performance-Qualified Shares which vest under the Award shall be made solely in shares of Common Stock.

7.Special Deferral Election. Provided Participant is a U.S. tax resident and subject to Participant's satisfaction of any applicable Withholding Tax obligations under Paragraph 6 and any other eligibility requirements established by the Administrator for a deferral election hereunder, Participant may elect to defer the issuance date of any shares of Common Stock which may become issuable to Participant pursuant to the terms of this Agreement, by submitting to the Corporation on a timely basis a deferral election in the form provided for such purpose. Such deferral election must be submitted to the Corporation prior to the last six (6) months of the Performance Period (including any abbreviated Performance Period) applicable to the shares for which the deferral election is made, and any deferral election submitted within that six (6)-month period or after the performance-based compensation subject to that election has become ascertainable shall have no force and effect. The deferral election must specify one or more deferred issuance dates or events that qualify as permissible distribution events under Code Section 409A and the Treasury Regulations thereunder. In submitting such deferral election, Participant must represent that he or she understands the effect of such deferral under relevant federal, state and local income and employment tax laws, including (without limitation) the fact that Social Security, Medicare and other taxes may be due upon the vesting of the shares of Common Stock notwithstanding the deferral election. In no event may such a deferral election be made after Participant's cessation of Continuous Service, and no deferral election shall have any force or effect unless such election complies with all applicable requirements of Code Section 409A and the Treasury Regulations thereunder.

8.Leaves of Absence. For purposes of applying the various Continuous Service vesting provisions of this Agreement, Participant shall be deemed to cease Continuous Service on the commencement date of any leave of absence and not to remain in Continuous Service status during the period of that leave, except to the extent otherwise required under employment laws in the jurisdiction where Participant is employed or pursuant to the following policy:

-    Participant shall be deemed to remain in Continuous Service status during (i) the first three (3) months of an approved personal leave of absence or (ii) the first seven (7) months of any bona fide leave of absence (other than an approved personal leave) and shall be deemed to cease Continuous Service upon the expiration of the applicable three (3)-month or seven (7)-month period.

-    In no event, however, shall Participant be deemed, for vesting purposes hereunder, to remain in Continuous Service beyond the earlier of (i) the expiration date of that leave of absence, unless Participant returns to active Continuous Service or Employee status on or before that date, or (ii) the date Participant's Continuous Service or Employee status actually terminates by reason of his or her voluntary or involuntary termination or by reason of his or her death or disability.

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9.Compliance with Laws and Regulations. The issuance of shares of Common Stock pursuant to the Award shall be subject to compliance by the Corporation and Participant with all Applicable Laws relating thereto.

10.Notices. Any notice required to be given or delivered to the Corporation under the terms of this Agreement shall be in writing and addressed to the Corporation at its principal corporate offices. Any notice required to be given or delivered to Participant shall be in writing and addressed to Participant at the most current address then indicated for Participant on the Corporation's employee records or shall be delivered electronically to Participant through the Corporation's electronic mail system or through an on-line brokerage firm authorized by the Corporation to effect sales of the Common Stock issued hereunder. All notices shall be deemed effective upon personal delivery or delivery through the Corporation's electronic mail system or upon deposit in the U.S. mail, postage prepaid and properly addressed to the party to be notified.

11.Successors and Assigns. Except to the extent otherwise provided in this Agreement, the provisions of this Agreement shall inure to the benefit of, and be binding upon, the Corporation and its successors and assigns and Participant, Participant's assigns, the legal representatives, heirs and legatees of Participant's estate and any beneficiaries of the Award designated by Participant.

12.Code Section 409A

(a)It is the intention of the parties that the provisions of this Agreement shall, to the maximum extent permissible, comply with the requirements of the short-term deferral exception to Section 409A of the Code and Treasury Regulations Section 1.409A-1(b)(4) with respect to each Tranche of Performance Shares under this Award. Accordingly, to the extent there is any ambiguity as to whether one or more provisions of this Agreement would otherwise contravene the requirements or limitations of Code Section 409A applicable to such short-term deferral exception, then those provisions, as they apply to each Tranche, shall be interpreted and applied in a manner that does not result in a violation of the requirements or limitations of Code Section 409A and the Treasury Regulations thereunder that apply to such exception.

(b)However, to the extent this Agreement should be deemed to create a deferred compensation arrangement subject to the requirements of Code Section 409A with respect to one or more Tranches of the Performance Shares, whether by reason of any deferral election made pursuant to Paragraph 7 above or the pro-rata service-vesting provisions of this Agreement, then the following provisions shall apply with respect to any such Tranche, notwithstanding anything to the contrary set forth herein:

-    No shares of Common Stock or other amounts which become issuable or distributable with respect to such Tranche by reason of Participant's cessation of Continuous Service shall actually be issued or distributed to Participant until the date of Participant's Separation from Service or as soon thereafter as administratively practicable, but in no event later than the later of (i) the close of the calendar year in which such Separation from Service occurs or (ii) the fifteenth day of the third calendar month following the date of such Separation from Service.

-    No shares of Common Stock or other amounts which become issuable or distributable with respect to such Tranche by reason of Participant's cessation of Continuous Service shall actually be issued or distributed to Participant prior to the earlier of (i) the first day of the seventh (7th) month following the date of Participant's Separation from Service or (ii) the date of Participant's death, if Participant is deemed at the time of such Separation from Service to be a specified employee under Section 1.409A-1(i) of the Treasury Regulations

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issued under Code Section 409A, as determined by the Administrator in accordance with consistent and uniform standards applied to all other Code Section 409A arrangements of the Corporation, and such delayed commencement is otherwise required in order to avoid a prohibited distribution under Code Section 409A(a)(2). The deferred shares of Common Stock or other distributable amount shall be issued or distributed in a lump sum on the first day of the seventh (7th) month following the date of Participant's Separation from Service or, if earlier, the first day of the month immediately following the date the Corporation receives proof of Participant's death.

-    No amounts that vest and become payable under Paragraph 4 of this Agreement with respect to that Tranche by reason of a Change in Control shall be distributed to Participant at the time of such Change in Control, unless that transaction also constitutes a Qualifying Change in Control. In the absence of such a Qualifying Change in Control, the distribution shall not be made until the date on which the shares to which those amounts pertain would have become issuable in accordance with the provisions of Paragraph 6(a) of this Agreement.

-    If Participant has made a deferral election under Paragraph 7 of this Agreement with respect to any Tranche of Performance Shares under this Award, no amounts that vest and become payable under Paragraph 4 with respect to that particular Tranche by reason of a Change in Control shall be distributed to Participant at the time of that Change in Control unless (i) the transaction also constitutes a Qualifying Change in Control and (ii) such deferral election provides for a distribution upon such an event. In the absence of such a Qualifying Change in Control or distribution election tied thereto, the distribution shall not be made until the date on which the shares of Common Stock to which those amounts pertain would have become issuable in accordance with Participant's deferral election under Paragraph 7 of this Agreement.

-     The shares of Common Stock that are issuable pursuant to each Tranche of Performance Shares in accordance with the provisions of this Agreement and attached Schedule I shall be deemed a separate payment for purposes of Code Section 409A.

13.Construction. This Agreement and the Award evidenced hereby are made and granted pursuant to the Plan and are in all respects limited by and subject to the terms of the Plan. In the event of any conflict between the provisions of this Agreement and the terms of the Plan, the terms of the Plan shall be controlling. All decisions of the Administrator with respect to any question or issue arising under the Plan or this Agreement shall be conclusive and binding on all persons having an interest in the Award.

14.Governing Law/Venue. The interpretation, performance and enforcement of this Agreement shall be governed by the laws of the State of Delaware without resort to that State's conflict-of-laws rules. For purposes of any action, lawsuit or other proceedings brought to enforce this Agreement or otherwise relating to or arising from this Agreement, the parties hereby submit to and consent to the sole and exclusive jurisdiction of the courts of San Mateo County, California, or the federal courts for the United States for the Northern District of California, and no other courts, where this grant is made and/or to be performed.

15.Employment at Will. Nothing in this Agreement or in the Plan shall confer upon Participant any right to remain in Continuous Service for any period of specific duration or interfere with or otherwise restrict in any way the rights of the Corporation (or any Related Entity employing or retaining

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Participant) or of Participant, which rights are hereby expressly reserved by each, to terminate Participant's Continuous Service at any time for any reason, with or without Cause.

16.Plan Prospectus. The official prospectus for the Plan is available on the Corporation's intranet at: http://gnet/ HR/stocks_new.asp. Participant may also obtain a printed copy of the prospectus by contacting Stock Plan Services at stockplanservices@gilead.com.

17.ElectronicDeliveryandAcceptance. The Corporation may, in its sole discretion, decide to deliver any documents related to current or future participation in the Plan by electronic means. Participant hereby consents to receive such documents by electronic delivery and agrees to participate in the Plan through an on-line or electronic system established and maintained by the Corporation or a third party designated by the Corporation.

18.Severability. The provisions of this Agreement are severable and if any one or more provisions are determined to be illegal or otherwise unenforceable, in whole or in part, the remaining provisions shall nevertheless be binding and enforceable.

19.Waiver. Participant acknowledges that a waiver by the Corporation of breach of any provision of this Agreement shall not operate or be construed as a waiver of any other provision of this Agreement, or of any subsequent breach of this Agreement.

20.Participant Acceptance. Participant must accept the terms and conditions of this Agreement either electronically through the electronic acceptance procedure established by the Corporation or through a written acceptance delivered to the Corporation in a form satisfactory to the Corporation. In no event shall any shares of Common Stock be issued (or other securities or property distributed) under this Agreement in the absence of such acceptance.

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IN WITNESS WHEREOF, Gilead Sciences, Inc. has caused this Agreement to be executed on its behalf by its duly-authorized officer on the day and year first indicated above.

GILEAD SCIENCES, INC.

By:

Title:

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APPENDIX A

DEFINITIONS

The following definitions shall be in effect under the Agreement:

A.Administrator shall mean the Compensation Committee of the Board acting in its capacity as administrator of the Plan.

B.Agreement shall mean this Performance Share Award Agreement.

C.Applicable Laws shall mean the legal requirements related to the Plan and the Award under applicable provisions of the federal securities laws, state corporate and securities laws, the Code, the rules of any applicable Stock Exchange on which the Common Stock is listed for trading, and the rules of any non-U.S. jurisdiction applicable to Awards granted to residents therein.

D.Award shall mean the award of Performance Shares made to Participant pursuant to the terms of this Agreement.

E.Award Date shall mean the date the Performance Shares are awarded to Participant pursuant to the Agreement and shall be the date indicated in Paragraph 1 of the Agreement.

F.Board shall mean the Corporation's Board of Directors.

G.Cause shall have the meaning assigned to such term in Section 11(c) of the Plan.

H.Change in Control shall mean a change in ownership or control of the Corporation effected through the consummation of any of the following transactions:

(i)a merger, consolidation or other reorganization approved by the Corporation's stockholders, unless securities representing more than fifty percent (50%) of the total combined voting power of the voting securities of the successor corporation are immediately thereafter beneficially owned, directly or indirectly and in substantially the same proportion, by the persons who beneficially owned the Corporation's outstanding voting securities immediately prior to such transaction;

(ii)a sale, transfer or other disposition of all or substantially all of the Corporation's assets;

(iii)the closing of any transaction or series of related transactions pursuant to which any person or any group of persons comprising a “group” within the meaning of Rule 13d-5(b)(1) of the 1934 Act (other than the Corporation or a person that, prior to such transaction or series of related transactions, directly or indirectly controls, is controlled by or is under common control with, the Corporation) becomes directly or indirectly (whether as a result of a single acquisition or by reason of one or more acquisitions within the twelve (12)-month period ending with the most recent acquisition) the beneficial owner (within the meaning of Rule 13d-3 of the 1934 Act) of securities possessing (or convertible into or exercisable for securities possessing) more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities (as measured in terms of the power to vote with respect to the election of Board members) outstanding immediately after the

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consummation of such transaction or series of related transactions, whether such transaction involves a direct issuance from the Corporation or the acquisition of outstanding securities held by one or more of the Corporation's existing stockholders; or

(iv)a change in the composition of the Board over a period of twelve (12) consecutive months or less such that a majority of the Board members ceases, by reason of one or more contested elections for Board membership, to be comprised of individuals who either (A) have been Board members continuously since the beginning of such period or (B) have been elected or nominated for election as Board members during such period by at least a majority of the Board members described in clause (A) who were still in office at the time the Board approved such election or nomination.

In no event, however, shall a Change in Control be deemed to occur upon a merger, consolidation or other reorganization effected primarily to change the State of the Corporation's incorporation or to create a holding company structure pursuant to which the Corporation becomes a wholly-owned subsidiary of an entity whose outstanding voting securities immediately after its formation are beneficially owned, directly or indirectly and in substantially the same proportion, by the persons who beneficially owned the Corporation's outstanding voting securities immediately prior to the formation of such entity. Should such holding company structure or other Parent entity be established for the Corporation, then subparagraph (iv) shall be applied solely to the board of directors of that holding company or Parent entity.

I.    Code shall mean the Internal Revenue Code of 1986, as amended.

J.    Common Stock shall mean shares of the Corporation's common stock.

K.    Constructive Termination shall have the meaning assigned to such term in Section 11(d) of the Plan.

L.    Consultant shall mean any person, including an advisor, who is compensated by the Corporation or any Related Entity for services performed as a non-employee consultant; provided, however, that the term “Consultant” shall not include non-employee Directors serving in their capacity as Board members. The term “Consultant” shall include a member of the board of directors of a Related Entity.

M.    Continuous Service shall mean the performance of services for the Corporation or a Related Entity (whether now existing or subsequently established) by a person in the capacity of an Employee, Director or Consultant. For purposes of this Agreement, Participant shall be deemed to cease Continuous Service immediately upon the occurrence of either of the following events: (i) Participant no longer performs services in any of the foregoing capacities for the Corporation or any Related Entity or (ii) the entity for which Participant is performing such services ceases to remain a Related Entity of the Corporation, even though Participant may subsequently continue to perform services for that entity. The Administrator shall have the exclusive discretion to determine when Participant ceases Continuous Service for purposes of the Award.

N.    Corporation shall mean Gilead Sciences, Inc., a Delaware corporation, and any successor corporation to all or substantially all of the assets or voting stock of Gilead Sciences, Inc. which shall by appropriate action adopt the Plan.

O.    Director shall mean a member of the Board.

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P.    Employee shall mean an individual who is in the employ of the Corporation (or any Related Entity), subject to the control and direction of the employer entity as to both the work to be performed and the manner and method of performance.

Q.    Employer shall mean the Corporation or any Related Entity employing Participant.

R.    Fair Market Valueper share of Common Stock on any relevant date shall be the closing price per share of Common Stock (or the closing bid, if no sales were reported) on that date, as quoted on the Stock Exchange that is at the time serving as the primary trading market for the Common Stock; provided, however, that if there is no reported closing price or closing bid for that date, then the closing price or closing bid, as applicable, for the last trading date on which such closing price or closing bid was quoted shall be determinative of such Fair Market Value. The applicable quoted price shall be as reported in The Wall Street Journal or such other source as the Administrator deems reliable.

S.    1934 Act shall mean the Securities Exchange Act of 1934, as amended from time to time.

T.    Participant shall mean the person to whom the Award is made pursuant to the Agreement.

U.    Parent shall mean any corporation (other than the Corporation) in an unbroken chain of corporations ending with the Corporation, provided each corporation in the unbroken chain (other than the Corporation) owns, at the time of the determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain.

V.    Performance Goal shall, with respect to each separate Tranche of Performance Shares, mean the net product revenue performance goal established or to be established for that Tranche at one or more designated levels of attainment in accordance with the provisions of attached Schedule I (the “Revenue Performance Goal”) that must be subsequently attained in order to satisfy the performance-vesting requirement for the shares of Common Stock allocated to that particular Tranche.

W.    Performance Period shall mean the one-year period specified on attached Schedule I for each separate Tranche of Performance Shares over which the attainment of the Revenue Performance Goal applicable to that particular Tranche is to be measured.

X.    Performance-Qualified Shares shall, with respect to each separate Tranche of Performance Shares, mean the maximum number of shares of Common Stock in which Participant can vest based on the level at which the Performance Goal applicable to that particular Tranche is in fact attained and shall be calculated in accordance with the provisions of attached Schedule I. Each Performance-Qualified Share that vests pursuant to the terms of the Award shall entitle Participant to receive one share of Common Stock.

Y.    Performance Shares shall mean the number of phantom shares of Common Stock that shall be applied to the calculation of the maximum number of Performance-Qualified Shares (if any) based on the level at which the Performance Goal for each Tranche of Performance Shares is in fact attained over the applicable Performance Period for that Tranche.

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Z.    Permanent Disability shall mean the inability of Participant to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment expected to result in death or to be of continuous duration of twelve (12) months or more.

AA.    Plan shall mean the Corporation's 2004 Equity Incentive Plan, as amended.

BB.    Qualifying Change in Control shall mean a change in control of ownership of the Corporation effected by one or more of the following transactions:

(i)a merger or consolidation in which the Corporation is not the surviving entity and in which one person or a group of related persons (other than the Corporation or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation) acquires ownership of securities possessing more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities or constituting more than fifty percent (50%) of the total fair market value of the Corporation's outstanding securities;

(ii)the sale, transfer or other disposition of all or substantially all of the assets of the Corporation in complete liquidation or dissolution of the Corporation;

(iii)any reverse merger in which the Corporation is the surviving entity but in which one person or a group of related persons (other than the Corporation or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation) acquires ownership of securities possessing more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities or constituting more than fifty percent (50%) of the total fair market value of the Corporation's outstanding securities;

(iv)the acquisition, directly or indirectly, by any person or related group of persons (other than the Corporation or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation) of beneficial ownership of securities possessing more than fifty percent (50%) of the total combined voting power of the Corporation's outstanding securities or constituting more than fifty percent (50%) of the total fair market value of the Corporation's outstanding securities pursuant to a tender or exchange offer made directly to the Corporation's stockholders; or

(v)a change in the composition of the Board over a period of twelve (12) consecutive months or less such that a majority of the Board members ceases, by reason of one or more contested elections for Board membership, to be comprised of individuals who either (A) have been Board members continuously since the beginning of such period or (B) have been elected or nominated for election as Board members during such period by at least a majority of the Board members described in clause (A) who were still in office at the time the Board approved such election or nomination.

The foregoing definition of Qualifying Change in Control shall in all instances be applied and interpreted in such manner that the applicable Qualifying Change in Control transaction that serves as an issuance event for the shares of Common Stock subject to this Award (or distribution event for any amounts relating to those shares) that vest upon the occurrence of a Change in Control and are otherwise at the time subject to the issuance or distribution restrictions of Code Section 409A will also qualify as: (i) a change in the ownership of the Corporation, as determined in accordance with Section 1.409A-3(i)(5)(v) of the Treasury

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Regulations, (ii) a change in the effective control of the Corporation, as determined in accordance with Section 1.409A-3(i)(5)(vi) of the Treasury Regulations, or (iii) a change in the ownership of a substantial portion of the assets of the Corporation, as determined in accordance with Section 1.409A-3(i)(5)(vii) of the Treasury Regulations.

CC.    Related Entity shall mean (i) any Parent or Subsidiary of the Corporation and (ii) any corporation in an unbroken chain of corporations beginning with the Corporation and ending with the corporation in the chain for which Participant provides services as an Employee, Director or Consultant, provided each corporation in such chain owns securities representing at least fifty percent (50%) of the total outstanding voting power of the outstanding securities of another corporation or entity in such chain.

DD.    Retirement shall mean Participant's cessation of Employee status on or after the date on which his or her combined age and years of Continuous Service equal or exceed seventy (70) years.

EE.    Separation from Service shall mean Participant's cessation of Employee status by reason of his or her death, retirement or termination of employment. Participant shall be deemed to have terminated employment for such purpose at such time as the level of his or her bona fide services to be performed as an Employee (or as a consultant or independent contractor) permanently decreases to a level that is not more than twenty percent (20%) of the average level of services he or she rendered as an Employee during the immediately preceding thirty-six (36) months (or such shorter period for which he or she may have rendered such services). Solely for purposes of determining when a Separation from Service occurs, Participant will be deemed to continue in “Employee” status for so long as he or she remains in the employ of one or more members of the Employer Group, subject to the control and direction of the employer entity as to both the work to be performed and the manner and method of performance. “Employer Group” means the Corporation and any Parent or Subsidiary and any other corporation or business controlled by, controlling or under common control with, the Corporation, as determined in accordance with Sections 414(b) and (c) of the Code and the Treasury Regulations thereunder, except that in applying Sections 1563(1), (2) and (3) of the Code for purposes of determining the controlled group of corporations under Section 414(b), the phrase “at least 50 percent” shall be used instead of “at least 80 percent” each place the latter phrase appears in such sections and in applying Section 1.414(c)-2 of the Treasury Regulations for purposes of determining trades or businesses that are under common control for purposes of Section 414(c), the phrase “at least 50 percent” shall be used instead of “at least 80 percent” each place the latter phrase appears in Section 1.414(c)-2 of the Treasury Regulations. Any such determination as to Separation from Service, however, shall be made in accordance with the applicable standards of the Treasury Regulations issued under Section 409A of the Code.

FF.    Service Period shall, with respect to each Tranche of Performance Shares, mean the applicable service period specified for that particular Tranche in attached Schedule I over which the Continuous Service vesting requirement in effect for that Tranche is to be measured.

GG.    Stock Exchange shall mean the American Stock Exchange, the Nasdaq Global or Global Select Market or the New York Stock Exchange.

HH.    Subsidiary shall mean any corporation (other than the Corporation) in an unbroken chain of corporations beginning with the Corporation, provided each corporation (other than the last corporation) in the unbroken chain owns, at the time of the determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain.

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II.    Tranche shall mean the three separate tranches (Tranche One, Tranche Two andTranche Three) into which the Performance Shares subject to this Award are divided in accordance with the provisions of Paragraph 1 of this Agreement and attached Schedule I.

JJ.    Withholding Taxes shall mean the federal, state and local income taxes and the employee portion of the federal, state and local employment taxes required to be withheld by the Corporation in connection with the vesting and issuance of the shares of Common Stock which vest under of the Award, any phantom dividend equivalents distributed with respect to those shares and any other amounts distributable in replacement or substitution of such shares.

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SCHEDULE I

PERFORMANCE GOALS AND PERFORMANCE PERIODS FOR THE THREE TRANCHES OF PERFORMANCE SHARES

ESTABLISHMENT OF SEPARATE TRANCHES

The number of Performance Shares subject to the Award has, in accordance with Paragraph 1 of this Agreement, been divided into three (3) separate Tranches: Tranche One, Tranche Two and Tranche Three. Each such separate Tranche shall cover one-third of the number of Performance Shares subject to this Award and shall have its own separate Performance Period and Service Period.

PERFORMANCE PERIOD FOR TRANCHE ONE

The measurement period for the Performance Goal for the Performance Shares allocated to Tranche One shall be the one-year period coincident with the Corporation's 2013 calendar fiscal year (the “Tranche One Performance Period”).

SERVICE PERIOD FOR TRANCHE ONE

The applicable Service Period to which the Performance Goal for Tranche One relates shall be the three (3)-year period beginning January 1, 2013 and ending December 31, 2015.

PERFORMANCE GOAL FOR PERFORMANCE VESTING FOR TRANCHE ONE

Performance Goal for Tranche One: The performance-vesting requirement for the Performance Shares allocated to Tranche One shall be tied to the Corporation's recognition of net product revenue for the Tranche One Performance Period in a dollar amount ranging from $9.6 Billion at twenty percent (20%) threshold level attainment to $10 Billion at target level attainment and to $10.2 Billion at maximum level attainment, with the net product revenue goal at any other point within such range to be in the dollar amount determined on a straight-line interpolated basis pursuant to the 2013 Fiscal Year Revenue Goal/Revenue Payout Slope set forth below. For purposes of determining whether such Revenue Performance Goal is attained, the actual level of net product revenue recognized by the Corporation for the Tranche One Performance Period shall be the net product revenue of the Corporation and its consolidated subsidiaries that is reported on a consolidated basis in the Corporation's audited consolidated financial statements for the calendar fiscal year coincident with the Tranche One Performance Period, adjusted, however, to factor out the effect of any changes in applicable accounting principles that occur after the start of such period.

Performance-Qualified Shares: Within sixty-five (65) days after the completion of the Tranche One Performance Period, the Administrator shall determine and certify the actual dollar amount of net product revenue recognized by the Corporation on a consolidated basis for the Tranche One Performance Period. The actual number of Performance-Qualified Shares that results from such certification (the “Tranche One Performance-Qualified Shares”) may range from 0% to 200% of the number of Performance Shares allocated to Tranche One in accordance with Paragraph 1 of this Agreement, with the actual percentage to be determined on the basis of the dollar amount of net product revenue that the Administrator certifies has in fact been recognized for the Tranche One Performance Period, as measured and reported on a consolidated basis with the Corporation's subsidiaries in accordance with the Corporation's audited consolidated financial statements for the Corporation's calendar fiscal year coincident with the Tranche One Performance Period; provided, however, that the maximum number of the shares of Common Stock that may qualify as Tranche One Performance-Qualified Shares may not exceed 200% of the number of Performance Shares allocated to Tranche One in accordance with Paragraph 1 of this Agreement.

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Payout Slope for Determining Number of Performance-Qualified Shares Based on Attained Level of Tranche One Performance Goal: The number of shares of Common Stock that may qualify as Tranche One Performance-Qualified Shares on the basis of the certified dollar amount of net product revenue recognized by the Corporation on a consolidated basis for the Tranche One Performance Period shall be calculated by multiplying the number of Performance Shares allocated to Tranche One in accordance with Paragraph 1 of this Agreement by the applicable percentage determined in accordance with the following revenue goal/payout slope for the Tranche One Performance Goal (with appropriate straight-line interpolation for any attained level within two otherwise designated levels in such slope):

PERFORMANCE PERIOD FOR TRANCHE TWO

The measurement period for the Performance Goal for the Performance Shares allocated to Tranche Two shall be the one-year period coincident with the Corporation's 2014 calendar fiscal year (the “Tranche Two Performance Period”).

SERVICE PERIOD FOR TRANCHE TWO

The applicable Service Period to which the Revenue Performance Goal for Tranche Two relates shall be the two (2)-year period beginning January 1, 2014 and ending December 31, 2015.

PERFORMANCE GOAL FOR PERFORMANCE VESTING FOR TRANCHE TWO

Performance Goal for Tranche Two: The performance-vesting requirement for the Performance Shares allocated to Tranche Two shall be tied to the Corporation's recognition of net product revenue for the Tranche Two Performance Period in the dollar amounts (at threshold, target and maximum levels, with appropriate straight-line interpolation between any two such designated levels) to be set by the Administrator no later than ninety (90) days after the start of that performance period, with the actual level of Revenue Performance Goal attainment for the Tranche Two Performance Period to be as measured and reported on a consolidated basis with the Corporation's subsidiaries in the Corporation's audited consolidated financial statements for the calendar fiscal year coincident with the Tranche Two Performance Period, adjusted, however, to factor out the effect of any changes in applicable accounting principles that occur after the start of such performance period. Promptly following the Administrator's establishment of the applicable Revenue Performance Goal for the Tranche Two Performance Period, Participant shall be provided with written notice of the applicable revenue goal levels and payout slope approved by the Administrator with respect to that goal.

Performance-Qualified Shares: Within sixty-five (65) days after the completion of the Tranche Two Performance Period, the Administrator shall determine and certify the actual dollar amount of net product revenue recognized by the Corporation on a consolidated basis for the Tranche Two Performance Period. The actual number of Performance-Qualified Shares that results from such certification (the “Tranche Two Performance-Qualified Shares”) may range from 0% to 200% of the number of Performance Shares allocated to Tranche Two in accordance with Paragraph 1 of this Agreement, with the actual percentage to be determined on the basis of the dollar amount of net product revenue that the Administrator certifies has in fact been recognized for the Tranche Two Performance Period, as measured and reported on a consolidated basis with the Corporation's subsidiaries in accordance with the Corporation's audited consolidated financial statements for the Corporation's calendar fiscal year coincident with the Tranche Two Performance Period; provided, however, that the maximum number of the shares of Common Stock that may qualify as Tranche Two

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Performance-Qualified Shares may not exceed 200% of the number of Performance Shares allocated to Tranche Two in accordance with Paragraph 1 of this Agreement.

Payout Slope for Determining Number of Performance-Qualified Shares Based on Attained Level of Tranche Two Performance Goal: The number of shares of Common Stock that may qualify as Tranche Two Performance-Qualified Shares on the basis of the certified dollar amount of net product revenue recognized by the Corporation on a consolidated basis for the Tranche Two Performance Period shall be calculated by multiplying the number of Performance Shares allocated to Tranche Two in accordance with Paragraph 1 of this Agreement by the applicable percentage determined in accordance with the payout slope (with appropriate straight-line interpolation for any attained level within two otherwise designated levels in such slope) approved by the Administrator at the same time it establishes the applicable Revenue Performance Goal for the Tranche Two Performance Period. 

PERFORMANCE PERIOD FOR TRANCHE THREE

The measurement period for the Performance Goal for the Performance Shares allocated to Tranche Three shall be the one-year period coincident with the Corporation's 2015 calendar fiscal year (the “Tranche Three Performance Period”).

SERVICE PERIOD FOR TRANCHE THREE

The applicable Service Period to which the Revenue Performance Goal for Tranche Three relates shall be the one (1)-year period beginning January 1, 2015 and ending December 31, 2015.

PERFORMANCE GOAL FOR PERFORMANCE VESTING FOR TRANCHE THREE

Performance Goal for Tranche Three: The performance-vesting requirement for the Performance Shares allocated to Tranche Three shall be tied to the Corporation's recognition of net product revenue for the Tranche Three Performance Period in the dollar amounts (at threshold, target and maximum levels, with appropriate straight-line interpolation between any two such designated levels) to be set by the Administrator no later than ninety (90) days after the start of that performance period, with the actual level of Revenue Performance Goal attainment for the Tranche Three Performance Period to be as measured and reported on a consolidated basis with the Corporation's subsidiaries in the Corporation's audited consolidated financial statements for the calendar fiscal year coincident with the Tranche Three Performance Period, adjusted, however, to factor out the effect of any changes in applicable accounting principles that occur after the start of such performance period. Promptly following the Administrator's establishment of the applicable Revenue Performance Goal for the Tranche Three Performance Period, Participant shall be provided with written notice of that goal and the applicable payout slope approved by the Administrator with respect to that goal.

Performance-Qualified Shares: Within sixty-five (65) days after the completion of the Tranche Three Performance Period, the Administrator shall determine and certify the actual dollar amount of net product revenue recognized by the Corporation on a consolidated basis for the Tranche Three Performance Period. The actual number of Performance-Qualified Shares that results from such certification (the “Tranche Three Performance-Qualified Shares”) may range from 0% to 200% of the number of Performance Shares allocated to Tranche Three in accordance with Paragraph 1 of this Agreement, with the actual percentage to be determined on the basis of the dollar amount of net product revenue that the Administrator certifies has in fact been recognized for the Tranche Three Performance Period, as measured on a consolidated basis with the Corporation's subsidiaries in accordance with the Corporation's audited consolidated financial statements for the Corporation's calendar fiscal year coincident with the Tranche Three Performance Period; provided, however, that the maximum number of the shares of Common Stock that may qualify as Tranche Three

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Performance-Qualified Shares may not exceed 200% of the number of Performance Shares allocated to Tranche Three in accordance with Paragraph 1 of this Agreement.

Payout Slope for Determining Number of Performance-Qualified Shares Based on Attained Level of Tranche Three Performance Goal: The number of shares of Common Stock that may qualify as Tranche Three Performance-Qualified Shares on the basis of the certified dollar amount of net product revenue recognized by the Corporation on a consolidated basis for the Tranche Three Performance Period shall be calculated by multiplying the number of Performance Shares allocated to Tranche Three in accordance with Paragraph 1 of this Agreement by the applicable percentage determined in accordance with the payout slope (with appropriate straight-line interpolation for any attained level within two otherwise designated levels in such slope) approved by the Administrator at the same time it establishes the applicable Revenue Performance Goal for the Tranche Three Performance Period.

CONTINUOUS SERVICE VESTING REQUIREMENT FOR PERFORMANCE-QUALIFIED SHARES

The number of shares of Common Stock in which Participant may actually vest on the basis of the number of Performance-Qualified Shares certified by the Administrator for each separate Tranche of Performance Shares in accordance with the foregoing provisions shall be tied to his or her completion of the following Continuous Service vesting requirement applicable to each such Tranche:

-    If Participant remains in Continuous Service through the last day of the applicable Service Period specified above for that Tranche, then Participant shall vest in one hundred percent (100%) of the Performance-Qualified Shares certified by the Administrator for that Tranche.

-    If Participant's Continuous Service terminates prior to the last day of the applicable Service Period specified above for that Tranche by reason of Retirement, death or Permanent Disability, then Participant shall, following the completion of the applicable Service Period for that Tranche, vest in that number of shares of Common Stock (if any) determined by multiplying the maximum number of Performance-Qualified Shares in which Participant could vest under that particular Tranche, based on the actual level at which the Revenue Performance Goal for that Tranche is attained and certified, by a fraction the numerator of which is the number of months of Continuous Service actually completed by Participant in the applicable Service Period for that Tranche (rounded to the closest whole month) and the denominator of which is the number of months (rounded to the closest whole number) constituting the Service Period specified above for that Tranche.

-    If Participant's Continuous Service ceases for any other reason (including, without limitation, any deemed cessation of Continuous Service under Paragraph 8 of this Agreement) prior to the completion of the applicable Service Period specified above for that Tranche, then Participant shall not vest in any of the Performance-Qualified Shares covered by that Tranche, and all of Participant's right, title and interest to the shares of Common Stock underlying that Tranche shall immediately terminate; provided, however, that should a Change in Control occur prior to the completion of the applicable Service Period for that Tranche, then the provisions of Paragraph 4 of the Agreement shall govern the vesting of the Performance Shares (if any) allocated to that Tranche.

-    Notwithstanding anything to the contrary in the foregoing provisions of this Continuous Service section, should Participant's Continuous Service cease for any

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reason prior to the start of the Service Period specified above for any particular Tranche of Performance Shares, then Participant shall not vest in any of the Performance Shares allocated to that Tranche, and all of Participant's right, title and interest to the shares of Common Stock underlying that Tranche shall immediately terminate.

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EX-10.95

Exhibit 10.95

AMENDED AND RESTATED SECOND AMENDMENT TO THE

LICENSE AND COLLABORATION AGREEMENT

This Amended and Restated Second Amendment to the License and Collaboration Agreement (this “Amended and Restated Second Amendment”) is made as of February 7, 2013 (the “Restated Second Amendment Effective Date”), by and among Gilead Sciences, Inc., a corporation organized and existing under the laws of the State of Delaware and having its principal place of business at 333 Lakeside Drive, Foster City, California 94404 (“Gilead Parent”), Gilead Sciences Limited, a corporation existing under the laws of Ireland and wholly-owned subsidiary of Gilead Parent having its principal place of business at IDA Business & Technology Park, Carrigtohill, Co. Cork, Ireland (“Gilead Sub” and, collectively with Gilead Parent, “Gilead”) and Janssen R&D Ireland, a company organized and existing under the laws of Ireland, having its principal place of business at Eastgate Village, Eastgate, Little Island, County Cork, Ireland (“Janssen”). Each of Gilead and Janssen is sometimes referred to individually herein as a “Party” and collectively as the “Parties.”

WHEREAS, Gilead and Janssen previously entered into that certain License and Collaboration Agreement, dated as of July 16, 2009 (as amended from time to time, the “Agreement”);

WHEREAS, Gilead and Janssen previously entered into that certain First Amendment to the Agreement, dated as of September 14, 2010 (the “First Amendment”);

WHEREAS, Gilead and Janssen previously entered into that certain original Second Amendment to the Agreement (the “Original Second Amendment”), dated as of July 1, 2011 (the “Second Amendment Effective Date”);

WHEREAS, Janssen was formerly Tibotec Pharmaceuticals and has now changed its name to Janssen R&D Ireland and wishes to reflect this change in entity name; and

WHEREAS, Gilead and Janssen desire to amend and restate the Original Second Amendment to modify certain approaches to the sale of Combination Product in certain additional countries, reallocate the Parties' responsibilities with respect to certain countries and modify certain payment and distribution terms in such countries as between the Parties.

WHEREAS, Gilead and Janssen further desire to amend and restate the Original Second Amendment to clarify the Parties' responsibilities with respect to the [*].

NOW THEREFORE, in consideration of the premises and the mutual covenants set forth herein and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties agree to amend the Agreement as follows:

SECTION 1.Additional Definitions. The following new definitions shall be inserted into the Agreement:

13.1“Branded Region B/C Combination Product” shall mean any Territory Combination Product that is Manufactured by or on behalf of Gilead or its Affiliates (or by or on behalf of Janssen or its Affiliates pursuant to Section 8.5) in accordance with the Branded Region B/C Combination Product specifications set forth in Annex Z (including the tablet color and shape set forth therein) which specifications describe a product intended by the Parties to be sold or otherwise Distributed (or Manufactured for sale or other Distribution) exclusively in Region B or Region C.

13.2“Branded Region B/C Combination Product Trade Dress” shall have the meaning set forth in Section 6.8.

13.3“Early Period” shall have the meaning set forth in Section 10.6(a)(ii).

13.4“Existing Region” shall mean the Territory excluding Region A, Region B and Region C.

13.5“Expanded Existing Region” shall mean the Existing Region, including Russia, Mexico and Argentina.

13.6“Final TCP Invoice” shall mean an invoice or credit note issued to Janssen or its designated Affiliate in accordance with this Agreement at the end of the applicable Calendar Year for Triggering Sales of Territory Combination Product with respect to the Janssen Countries as set forth in Annex BB.

13.7“Final TMC278 Invoice” shall mean the invoice or credit note issued to Gilead or its designated Affiliate in accordance with this Agreement at the end of the applicable Calendar Year for the Regional TMC278 Annual True-Up with respect to the Gilead Countries as set forth in Annex N.

13.8“Generic Exception” shall have the meaning set forth in Section 17.2(a).

13.9“Generic Manufacturing Agreement” shall mean any agreement between Janssen or a Janssen Affiliate and a Gilead Licensee pursuant to which Janssen or its Affiliates grants such Gilead Licensee the right under intellectual property Controlled by Janssen and its Affiliates to Manufacture or commercialize Generic Region C Combination Product.

13.10“Generic Region C Combination Product” shall mean any generic Combination Product. For clarity, Generic Region C Combination Product does not constitute Territory Combination Product.

13.11“Gilead Licensee” shall mean, at a given time, any Third Party that is a party to an agreement with Gilead or any of its Affiliates under which Gilead or such Affiliate has granted to such Third Party rights to Manufacture and sell TDF, FTC or both (as API or in the form of a generic product) in the Field in Region C.

13.12“Gilead Region C Know-How” shall mean any and all Gilead Know-How necessary to make the Generic Region C Combination Product from TDF, FTC and TMC278.

13.13“Interim TCP Invoice” shall mean the invoice for Territory Combination Product issued to Janssen or its designated Affiliate in accordance with this Agreement that is calculated based on the TCP Interim Supply Price with respect to the Janssen Countries as set forth in Annex BB.

13.14“Janssen Licensee” shall mean, at a given time, any Third Party that is a party to an agreement with Janssen or any of its Affiliates under which Janssen or such Affiliate has granted to such Third Party rights to Manufacture and sell 27.5 mg TMC278 in combination with 300 mg TDF and 200 mg FTC in the Field in Region C.

13.15 “Joint Region C Know-How” shall mean any and all Joint Know-How necessary to make the Generic Region C Combination Product from TDF, FTC and TMC278.

13.16“LicensedGeneric Manufacturer” shall have the meaning set forth in Section 6.12(a).

13.17“Limited Region A” shall mean Region A, excluding Russia, Mexico and Argentina.

13.18“Major Market Combination Product” shall mean any Territory Combination Product that is manufactured by Gilead in accordance with the Major Market Combination Product specifications set forth in Annex Z which specifications describe a product intended by the Parties to be sold or otherwise Distributed (or Manufactured for sale or other Distribution) in the Territory outside of Region B or Region C, which shall, for the avoidance of doubt, exclude any Region B/C Combination Product.

13.19“Major Market Trade Dress” shall mean the tablet color, embossing and printing on the tablet, and the label, packaging and package insert for the Major Market Combination Product, in each case that has been approved by the applicable Regulatory Authorities, from time-to-time.

13.20“Region A” shall mean those countries designated in Annex AA as Region A countries.

13.21“Region B” shall mean those countries designated in Annex AA as Region B countries.

13.22“Region B/C CMO” shall have the meaning set forth in Section 8.5.

13.23“Region B/C Combination Product” shall mean Generic Region C Combination Product and Branded Region B/C Combination Product.

13.24“Region C” shall mean those countries designated in Annex AA as Region C countries.

13.25“Revaluation TCP Invoice” shall mean the invoice or credit note for revaluation of Interim TCP Invoices in accordance with Annex DD.

13.26“TCP Invoice” shall mean an Interim TCP Invoice, Revaluation TCP Invoice or a Final TCP Invoice, as applicable.

13.27“Third Party Component Distributor” shall mean a Third Party distributor that (a) purchases Truvada (or Viread and Emtriva in countries where Truvada is not sold) or the TMC278 Product, as applicable, from a Party or its Affiliates for distribution in a country in the Territory and (b) has the right to conduct the marketing, promotion, distribution, selling and other activities for the commercialization of such product.

SECTION 2.Combination Product and Gilead and Janssen Countries Definition.

2.1.Section 1.44 of the Agreement is hereby replaced in its entirety as follows: “Combination Product” shall mean the fixed-dose co-formulated product in oral dosage form containing, as its only APIs per single daily dose, 300 mg TDF, 200 mg FTC and 27.5 mg TMC 278, intended for adult and adolescent use, and once-daily administration. The “adolescent” population shall be determined by industry standards (generally, age twelve (12) years to adult or equivalent weight ranges), clinical data and Approvals by the Regulatory Authorities. Notwithstanding the foregoing, in no event shall the failure to secure Approval for an adolescent indication cause such product to fall outside of this definition.

2.2.Section 1.100 of the Agreement is hereby replaced in its entirety as follows: “Gilead Countries” shall mean all countries in the Territory, other than any Janssen Countries, as set forth in Annex AA.

2.3.Section 1.236 of the Agreement is hereby replaced in its entirety as follows: “Janssen Countries” shall mean those countries indicated as Janssen Countries in Annex AA.

2.4.Section 1.250 of the Agreement is hereby replaced in its entirety as follows; “TMC278 Product” shall mean that certain pharmaceutical product in oral form containing 27.5 mg TMC278 (which is equivalent

to 25 mg of rilpivirine) as its only active ingredient that was under development by Tibotec as of the Effective Date.

SECTION 3.27.5 mg of TMC278 and Associated Calculations.

3.1.Sections 1.63 and 17.2(a) are hereby amended by replacing the word “25 mg” where it appears in each such Section with the word “27.5 mg”.

3.2.Annex J is hereby amended by replacing the word “25 mg” where it appears in such Annex with the word “27.5 mg”.

3.3.Annex P is hereby amended by replacing all references to [*].

SECTION 4.Region Definition. Section 1.202 of the Agreement is hereby replaced in its entirety as follows:

“Region” shall mean, as applicable, the Existing Region, Expanded Existing Region, Limited Region A, Region A, Region B, Region C or Japan, or any combination of the foregoing, defined subdivision of the foregoing or defined grouping of subdivisions of the foregoing, as the case may be; provided, however, that Region as used in Sections 19.5(d), 19.5(e), 19.6(d) and 19.6(e) shall mean either (a) the United States and Canada, or (b) all countries in the Territory other than the United States and Canada, as the case may be.

SECTION 5.Selling Party Definition. Section 1.214 of the Agreement is hereby replaced in its entirety as follows:

“Selling Party” shall mean (a) Janssen in the case of the Janssen Countries and (b) Gilead in the case of the Gilead Countries.

SECTION 6.Specified Percentage Definition. Section 1.219 of the Agreement is hereby replaced in its entirety as follows:

“Specified Percentage” shall mean (a) in the case of all countries in the Territory other than the countries in [*], subject to adjustment, on a country-by-country basis, pursuant to Section 11.6, and (b) in the case of countries in [*].

SECTION 7.Territory Definition. Section 1.227 of the Agreement is hereby replaced in its entirety as follows:

“Territory” shall mean all countries of the world.

SECTION 8.Territory Combination Product Definition. Section 1.228 of the Agreement is hereby replaced in its entirety as follows:

“Territory Combination Product” shall mean any Combination Product sold or otherwise distributed (or Manufactured for sale or other distribution) pursuant to this Agreement or any Ancillary Agreement, excluding, for the avoidance of doubt, any Generic Region C Combination Product.

SECTION 9.Janssen Distributor Agreement Definition. Section 1.237 of the Agreement is hereby replaced in its entirety as follows:

“Janssen Distributor Agreement” shall mean, as applicable, Annex Z or any agreements entered into by Gilead and Janssen, or their respective Affiliates which the Parties agree supersede Annex Z with respect to

country(ies) in which Janssen is the Selling Party and pursuant to which Gilead sells the Territory Combination Product to Janssen, in bulk or bottled form, for Distribution in one or more Janssen Countries.

SECTION 10.Access Agreement Removal.

Section 1.4 of the Agreement is hereby deleted in its entirety.

SECTION 11.Change from Tibotec to Janssen.

All references and uses of the term “Tibotec” in the Agreement, whether alone or as part of the name of another defined term, are hereby replaced with the term “Janssen”.

SECTION 12.Other Combination Product Clinical Trials. Section 3.2(b)(iii) of the Agreement is hereby amended by deleting the text “or Japan” from the Section.

SECTION 13.Regulatory Matters

13.1Registration Plan Creation. Section 4.2(a) of the Agreement is hereby amended by inserting the following sentence at the end of such Section: Within sixty (60) days after the Second Amendment Effective Date, the Parties shall update the Registration Plan to cover the countries in Region A, Region B and Region C in which a Party or its applicable Affiliate or Third Party Distributor intends to launch the Branded Region B/C Combination Product.

13.2MA Holder. Section 4.4(a) of the Agreement is hereby amended and replaced in its entirety with the following: MA Holder. With respect to each country in the Territory, unless otherwise agreed to in writing by the Parties or prohibited by Applicable Law, Gilead, or its designated Affiliate or Third Party Distributor, shall hold the marketing authorization with respect to the Combination Product with respect to such country. Notwithstanding the foregoing, the Parties have agreed that Janssen, or its designated Affiliate or Third Party Distributor, will hold the marketing authorization with respect to the Combination Product in the countries set forth in the letter agreement entered into by the Parties, a copy of which is attached as Annex EE. In those countries in which the Parties have agreed in writing that Janssen, or its designated Affiliate or Third Party Distributor, will hold the marketing authorization with respect to the Combination Product, as well as in those countries in which Janssen as the Selling Party, or its designated Affiliate or Third Party Distributor, is required by Applicable Law to hold the marketing authorization, Janssen, or its designated Affiliate or Third Party Distributor shall hold the marketing authorization. [*].

SECTION 14.Product Information; Medical Affairs and Medical Communications.

14.1.Section 5.1(a) of the Agreement is hereby amended by inserting the words “and Section 6.3(b)” following the words “Section 5” in the first sentence.

14.2.Section 5.1(b) of the agreement is hereby amended by inserting the words “Subject to Section 6.3(b),” at the beginning of the first sentence.

SECTION 15.Distribution Rights and Related Matters. Section 6.1 of the Agreement is hereby replaced in its entirety as follows:

6.1    Janssen Distribution Rights and Related Matters.

(a)General Restrictions on Distribution of Territory Combination Products.

(i)Major Market Combination Product. Each Party and its Affiliates (A) may and shall only sell, offer for sale, or assist Third Parties in selling Major Market Combination Product in Region A for end use in the Field and in countries in Region A in which such Party is the Selling Party, and (B) shall not sell and shall prohibit its distributors and their respective wholesalers and distributors (if any are permitted pursuant to this Agreement) from selling Major Market Combination Product in Region B or Region C or from assisting any Third Party in doing so.

(ii)Branded Region B/C Combination Products. Each Party and its Affiliates (A) may and shall only sell, offer for sale, or assist Third Parties in selling Branded Region B/C Combination Product in Region B or Region C for end use in the Field and in countries in Region B or Region C in which such Party is the Selling Party, and (B) shall not sell and shall prohibit its distributors and their respective wholesalers and distributors (if any are permitted pursuant to this Agreement) from selling a Branded Region B/C Combination Product outside of Region B or Region C or from assisting any Third Party in doing so.

(iii)Generic Region C Combination Products. Each Party and its Affiliates (A) shall only sell, offer for sale, or assist Third Parties in selling Generic Region C Combination Product in Region C for end use in the Field, and (B) shall not sell and shall prohibit its distributors and their respective wholesalers and distributors (if any are permitted pursuant to this Agreement) from selling a Generic Region C Combination Product outside of Region C or from assisting any Third Party in doing so.

(b)Notification of Generic Sale for Region C. It is anticipated that Janssen (or its Affiliates or Third Party Distributors) may initially Distribute Branded Region B/C Combination Product in Region C where Janssen is the Selling Party. If at any time Janssen or any of its Affiliates or Third Party Distributors determines that it desires to sell Generic Region C Combination Product in a Janssen Country in Region C, Janssen shall promptly provide advance notice to Gilead of such election and specify in which Janssen Countries in Region C it intends to sell Generic Region C Combination Product.

(c)Non-Region B/C Combination Product. Neither Party nor any of its Affiliates shall be permitted to Distribute any Combination Product in Region C other than Region B/C Combination Product.

(d)Gilead Third Party Distributor Purchases in Region C. Nothing in this Agreement shall prevent Gilead's Third Party Distributors in Region C from purchasing Generic Region C Combination Product from a Licensed Generic Manufacturer and selling such Generic Region C Combination Product in those Region C countries where Gilead is the Selling Party.

SECTION 16.Specific Commercialization Obligations. Section 6.2(b)(iii) is amended by inserting the following sentence at the end of the Section: “Notwithstanding anything contained herein to the contrary, the Parties may from time to time mutually agree in writing on adjustments to the number of Details set forth in Annex F.”

SECTION 17.Detailing Election. Section 6.3(a) of the Agreement is hereby amended by replacing the word “Territory” in the first sentence with “Expanded Existing Region”.

SECTION 18.Other Promotion by Parties. Section 6.3(b) of the Agreement is hereby replaced in its entirety as follows:

(b)    Responses to Unsolicited Questions and Related Matters.

(i)For any country in the Existing Region, Janssen and its Affiliates may not market or promote (other than Detail) the Territory Combination Product, but may in connection with their activities relating to the TMC278 Product respond to unsolicited questions that they receive with respect to the Territory Combination Product. Gilead may elect to provide Janssen with an approved slide deck or other background materials for use in responding to such questions. In the event that Gilead does elect to provide such materials, Janssen and its Affiliates shall respond to any unsolicited questions that they receive with respect to the Territory Combination Product in a manner consistent with such materials (unless Janssen or its applicable Affiliate believes in good faith that such materials are inconsistent with Applicable Law or its corporate policies).

(ii)For any country in Region A, the non-Selling Party with respect to such country may respond to unsolicited questions solely in accordance with Applicable Law and based solely upon the Product Label and Insert for the Territory Combination Product in such country in Region A and any approved materials the Selling Party provides to the non-Selling Party for responding to such questions in such country, which approved materials may be withdrawn from use by the Selling Party at any time.

(iii)For any country in Region B or Region C, the non-Selling Party with respect to such country and its Affiliates shall not respond to any unsolicited question that they receive with respect to the Territory Combination Product and shall use reasonable efforts to refer any such unsolicited questions to the Selling Party for such country.

SECTION 19.Detailing of the TMC278 Product. Section 6.4 of the Agreement is hereby amended by inserting the phrase “, excluding any countries in Region A, Region B or Region C,” following the word “Territory” in the first sentence.

SECTION 20.Branded Region B/C Combination Product Trade Dress. Section 6.8 of the Agreement is hereby amended by:

20.1.Changing all references to “Combination Product” in such Section to “Territory Combination Product”; and

20.2.Inserting the following at the end of such Section: “All Branded Region B/C Combination Products shall have a different tablet color and tablet design and packaging than the Major Market Combination Product. Without limitation of the foregoing provisions of this Section 6.8, Gilead shall designate such tablet color and design and shall design the packaging for the Branded Region B/C Combination Product, which packaging (and only such packaging) shall be used by Janssen and its Affiliates and Third Party Distributors (the “Branded Region B/C Combination Product Trade Dress”); provided, however, that Janssen shall modify such packaging as required to comply with local Applicable Law and shall translate such packaging to the local language as necessary. Janssen shall notify Gilead and obtain Gilead's prior written approval of any such packaging modifications with respect to the Branded Region B/C Combination Product.”

SECTION 21.Licensed of Joint Technology to Generic Manufacturers. Section 6.12 of the Agreement is hereby inserted as follows:

6.12    Generic Region C Combination Product Licensed Manufacturers.

(a)Subject to the terms of this Agreement, notwithstanding Section 14.1(d) of this Agreement, Janssen shall have the right to license the Gilead Licensees under Janssen's interest in the Joint Technology and any intellectual property and other rights in and to TMC278 owned or otherwise

Controlled by Janssen and its Affiliates, in each case, to Manufacture and otherwise Exploit Generic Region C Combination Products solely in Region C (or any countries therein) (each Gilead Licensee so licensed by Janssen, a “LicensedGeneric Manufacturer”). For clarity, Janssen and its Affiliates are not themselves licensed by Gilead to Exploit TDF or FTC (other than in the Territory Combination Product) and therefore shall not have the right to grant any licenses under Gilead's intellectual property with respect to TDF or FTC.

(b)Each Party (i) represents and warrants that as of the Second Amendment Effective Date it has provided the other Party with a list of Janssen Licensees or Gilead Licensees, as applicable, that is complete and accurate as of the Second Amendment Effective Date and each Party shall, from time to time, provide the other Party a written update of such list to reflect any modifications to its Janssen Licensees or Gilead Licensees, as the case may be and (ii) from time to time, as requested by the other Party, shall provide a true and correct copy of [*] of this Agreement. Notwithstanding anything to the contrary hereunder or in any Ancillary Agreement, neither Gilead nor Janssen shall be liable for, nor be obligated to indemnify, hold harmless or defend the other Party or any of its Indemnified Persons with respect to any act or omission of any Gilead Licensee or Janssen Licensee, respectively, and any Losses or Proceedings arising therefrom provided that such Party has complied with its obligations hereunder with respect to such Gilead Licensee or Janssen Licensee.

SECTION 22.Trademark and Patent Lists for Region A, B and C. Section 6.13 of the Agreement is hereby inserted as follows:

6.13    Updated Trademark and Patent Lists. For the countries in Region A, Region B and Region C, at reasonable intervals, the Selling Party may request from the non-Selling Party updates to Annexes A and B to include the Patents and Trademarks covered thereby for such countries, in which case the non-Selling Party shall provide such update for its applicable Patents and Trademarks within a reasonable time following such request.

SECTION 23.Technology Transfer; Generic Licensees. Section 6.14 of the Agreement is hereby inserted as follows:

6.14    Technology Transfer Package. Upon the written request of Janssen, Gilead shall prepare a written technology transfer package of Gilead Region C Know-How and Joint Region C Know-How available to Gilead (the “Generic Technology Transfer Package”). If Janssen notifies Gilead of any [*].

SECTION 24.Modified Pricing. Section 7.7 of the Agreement is hereby inserted as follows:

7.7    Limited Region A, Region B and Region C Modified Pricing. Notwithstanding anything in this Agreement to the contrary, the pricing and discounting provisions for Limited Region A, Region B and Region C shall be governed by the provisions set forth in Annex Y (and not the other provisions of this Section 7 unless expressly provided for in Annex Y).

SECTION 25.Territory Combination Product Supply to Janssen. Section 8.2 of the Agreement is hereby replaced in its entirety and Section 8.5 is added as follows:

8.2    Territory Combination Product Supply to Janssen. The supply of Territory Combination Product to Janssen for Distribution in the Janssen Countries and the Distribution of such Territory Combination Product by Janssen shall be governed by the terms of this Agreement, including those set forth in Annex Z. The terms set forth in Annex Z shall constitute the Janssen Distribution Agreement for purposes of this Agreement.

8.5    [*].

SECTION 26.Retained Rights. Section 9.5 of the Agreement is hereby amended by inserting the following two (2) sentences at the end of such Section “Notwithstanding anything contained in this Section 9.5, none of the licenses granted under this Agreement apply to Generic Region C Combination Product. Notwithstanding any exclusivity or co-exclusivity granted in this Section 9, but subject to the terms of this Agreement, each Party and its Affiliates retains all rights under any intellectual property owned or Controlled by such Party or its Affiliates (other than Controlled as a result of the licenses granted in this Section 9), including its interest in the Joint Technology, to exercise its rights under such Party's Generic Exception.”

SECTION 27.Section 10.4 and Annex J. A new Section 10.4(e) of the Agreement is hereby inserted as follows:

(e)    Notwithstanding anything else in this Section 10.4 or Annex J, the provisions of this Section 10.4 and Annex J do not apply to any [*].

SECTION 28.Expired and Returned Product. Section 10.6 of the Agreement is hereby replaced in its entirety with the following:

10.6    Expired and Returned Product.

(a)Gilead Countries.

(i)If Gilead (or its applicable Affiliate) is unable to sell any quantities of Territory Combination Product packaged and labeled for countries in the Territory in which Gilead is the Selling Party in its reasonable discretion on account of product expiry (or short remaining shelf-life, as applicable), or such Combination Product is otherwise returned by a Customer (and such Customer is entitled to a credit in connection with such return pursuant to Gilead's (or its Affiliate's) applicable standard return policy (published and in effect immediately prior to such return)) to Gilead (or its applicable Affiliate), and cannot be resold (any such Combination Product that cannot be so sold or is so returned and cannot be resold, “Gilead Expired/Short-Dated Product”), then (A) Gilead shall destroy such Combination Product (which destruction shall be in accordance with Applicable Law), (B) within ten (10) Business Days following the end of each calendar month, Gilead shall notify Janssen of the quantity, if any, of Gilead Expired/Short-Dated Product designated, during such calendar month, for destruction (pursuant to Gilead's standard operating procedures), and (C) with respect to any Gilead Expired/Short-Dated Product, (1) notwithstanding anything in this Agreement or any Ancillary Agreement, the Manufacturing Fees that were incurred for any Gilead Expired/Short-Dated Product shall be borne, [*].

(ii)Notwithstanding anything preceding in Section 10.6(a)(i), during the period of time when Major Market Combination Product or Branded Region B/C Combination Product has [*]. The Parties shall coordinate in good faith to determine the timing and mechanics for effecting the foregoing adjustments and payments.

(b)Janssen Countries. Subject to Section 2.2 of the Janssen Distributor Agreement and Annex Z, Section 10.6(a)(i) shall apply to (i) Janssen as the Selling Party, mutatis mutandis, and (ii) any Territory Combination Product that was Delivered (as defined in Annex Z) to Janssen under the Janssen Distributor Agreement, which Territory Combination Product Janssen is [*].

SECTION 29.Taxes. Section 10.11 of the Agreement is hereby replaced in its entirety with the following:

10.11    Tax.

(a)Subject to Section 10.11(b), each Party shall be responsible for any and all sales, use, excise, value added, goods and services and similar taxes and charges imposed with respect to any payments to such Party by the other Party pursuant to this Section 10, and each Party shall be responsible for any taxes (including any such taxes imposed by way of withholding) in the nature of income or franchise taxes or based on or measured by gross or net income imposed with respect to its income. Subject to Section 10.11(b), each Party shall pay to the proper taxing authority any and all withholding taxes or similar charges imposed by any governmental unit that are required to be withheld from any amounts due to the other Party pursuant to this Section 10, and proof of payment of such taxes or charges shall be secured and sent to such other Party as evidence of such payment. All amounts withheld and paid by a Party pursuant to the immediately preceding sentence with respect to taxes for which the other Party is responsible pursuant to the first sentence of this Section 10.11 shall be paid for the account of such other Party and deducted from the amounts due from the paying Party to such other Party pursuant to this Section 10.

(b)If Janssen [*].

SECTION 30.Establishment/Adjustment of the Supply Prices. Section 11.5 of the Agreement is hereby replaced in its entirety with the following:

11.5    Establishment/Adjustment of the Supply Prices in the Janssen Countries and Gilead Countries.

(a)TMC278. Subject to the other terms and conditions of this Agreement, the TMC278 Supply Agreement shall provide that, with respect to any quantity of Supplied TMC278 ultimately used in Combination Product sold in the Territory, Janssen shall issue, and Gilead shall pay, a Pre-Conversion Invoice and, solely in the case of the Gilead Countries if there is a Triggering Sale, a Post-Conversion Invoice in accordance with the terms and procedures set forth on Annexes M and N such that Gilead pays to Janssen (i) the Pre-Conversion Supply Price and the Post-Conversion Supply Price for such Supplied TMC278 in the case of the Gilead Countries and (ii) in all other cases, [*]. On a monthly basis, no later than the tenth (10th) Business Day after the end of each month, Gilead shall calculate the Post-Conversion Supply Price for such Supplied TMC278 corresponding to Combination Product for which Triggering Sales occurred in Gilead Countries in such month in accordance with Annex N, and shall provide such Post-Conversion Supply Price to Janssen. All Pre-Conversion Supply Prices and Post-Conversion Supply Prices shall be calculated in U.S. Dollars. For the avoidance of doubt, to the extent the TMC278 Supply Agreement is inconsistent with Annex M and Annex N of this Agreement, as amended, the terms of Annex M and Annex N shall supersede the terms of the TMC278 Supply Agreement (including, for clarity, the limitation in Annex M and Annex N that [*].

(b)Territory Combination Product. The issuance of invoices and payment terms for Territory Combination Product sold by Gilead to Janssen or its Affiliates shall be determined according to the provisions set forth in Annex BB.

SECTION 31.Payment Terms for Region A, Region B and Region C. Section 11.6 of the Agreement is hereby amended by inserting the following sentence at the end of the Section: “The provisions of this Section 11.6 shall not apply to any of the countries in Region A, Region B or Region C.”

SECTION 32.Payment Term and Related Matters. Section 11.7(d) of the Agreement is hereby amended be inserting “Solely with respect to the Expanded Existing Region and any Triggering Sales occurring therein,” at the beginning of the first sentence of the section.

SECTION 33.Payment Terms for Region A, Region B and Region C. Section 11.7(e) of the Agreement is hereby replaced in its entirety with the following:

11.7(e)        Notwithstanding anything else in this Section 11.7, the payment terms for (i) Supplied TMC278 ultimately used in Combination Product sold in Region A, Region B and Region C are set forth in Annex M which, in the case of such Supplied TMC278, shall apply in lieu of the provisions in this Section 11.7 and (ii) Territory Combination Product sold to Janssen are set forth in Annex BB.

SECTION 34.A new Section 11.10 is added to the Agreement as follows:

11.10        Certain Shared Fees. The Parties agree that [*].

SECTION 35.Financial Records and Audit.

35.1.Section 12.1 of the Agreement is hereby replaced in its entirety with the following:

12.1    Financial Records. Each Party shall, and shall cause its applicable Affiliates, Third Party Distributors and any third party distributors of Truvada or the TMC278 Product, as applicable, to, keep complete and accurate books and records pertaining to information provided to the other Party pursuant to Section 7.4(a), 11.5 or 11.9 (or required to determine that the DCPs provided by such Party comply with the terms of this Agreement). Each Party shall keep, and shall cause its applicable Affiliates to keep, complete and accurate books and records pertaining to the determination of the Manufacturing Fees, the determination of any API Replacement Cost and any other amounts that one Party (or its Affiliates) may owe to the other Party (or its Affiliates) hereunder or under any Ancillary Agreement. Each Party shall, and shall cause its applicable Affiliates, Third Party Distributors and third party distributors of Truvada or the TMC278 Product, as applicable, to, keep such books and records for the longer of (a) five (5) years after the Calendar Quarter in which the applicable sales occurred or such costs and expenses were invoiced, (b) the expiration of the applicable statute of limitations for tax purposes (or any expiration thereof) or (c) such longer period as may be required by Applicable Law.

35.2.Sections 12.2(b) and (c) of the Agreement are hereby replaced in their entirety with the following:

(b)    Mutually Agreed Audits. Unless otherwise agreed by the Parties in writing, the Parties shall engage an Independent Accounting Expert to confirm, for each Calendar Year during the term of this Agreement, the accuracy of (i) any calculation by the Discount Committee, (ii) any pricing or discounting information provided to the Discount Committee or to either Party by the other Party pursuant to Section 7.4 or Annex R, (iii) any information of a Party or its Affiliates that is required to determine that the DCPs provided by such Party comply with the terms of this Agreement (including, for any Calendar Quarter up to and including the [*], (iv) the calculation of the TCP Final Supply Price for Major Market Combination Product Delivered for the Janssen Countries [*] and (v) the calculation of the Regional TMC278 Annual True-Up and the Post-Conversion Supply Price for Territory Combination Product with respect to the [*]; provided, however, that the foregoing shall not permit either Party to audit any Third Party Component Distributor, such audit being permitted solely as and to the extent provided in Section 12.2(c). The Parties shall mutually agree in writing on the desired scope of such audit. The Independent Accounting Expert shall conduct such other audits as mutually determined by the Parties in writing to confirm the accuracy of any financial data provided by or on behalf of either Party pursuant to Section 11.9.

(c)    Party Initiated Audits. Without limitation of Section 12.2(b), upon the request of either Party (the “Initiating Party”), the Independent Accounting Expert shall audit the other Party (the “Audited Party”) and its applicable Affiliates to examine (subject to Section 12.2(d)) the books and records maintained by

such Person pursuant to Section 12.1 to verify (i) any amounts reimbursable by the auditing Party hereunder or under any Ancillary Agreement, (ii) the determination of any API Replacement Cost, (iii) in the case of Gilead as the Audited Party, the Manufacturing Fees, (iv) any calculations required to be made pursuant to this Agreement, (v) any information or reports of such other Party provided pursuant to this Agreement, (vi) any information subject to the annual audit contemplated in Section 12.2(b), including the accuracy of such information from time to time with respect to one or more Customers, (vii) the accuracy of any information provided by or on behalf of any Party pursuant to Section 11.9 to the other Party to the extent that such information is used in any calculation hereunder with respect to the portion of costs and expenses borne, or revenue obtained, by the Initiating Party or any of its Affiliates hereunder or under any Ancillary Agreement and (viii) not more than one (1) time per Calendar Year and solely with respect to [*] is used in the calculations set forth in the Annexes hereto during the audited period. The Initiating Party shall conduct an audit the scope of which is commensurate with the underlying matters being audited as itemized in this Section 12.2(c) clauses (i) - (viii); provided, however, that any audits under clause (viii) shall be conducted solely by the Party that is party to the applicable agreement with such Third Party Component Distributor and in accordance with terms and conditions of such agreement using the Independent Audit Expert or other mutually acceptable certified or chartered accountant (in each case as permitted by the terms and conditions of such agreement) and the other Party shall only have the right to review the results of such audit generated by the contracting Party and such Independent Audit Expert or accountant to the extent such audit results may be revealed pursuant to the applicable Third Party Component Distributor agreement; provided, further, that this Section 12.2(c) shall not confer rights to any Party that exceed those rights set forth in the applicable agreement with such Third Party Component Distributor.

SECTION 36.Consequences of Inaccurate DCPs and Component Prices. Section 12.2(e) of the Agreement is hereby replaced in its entirety with the following:

(e)    Consequences of Inaccurate DCPs and Component Prices.

(i)    NOTWITHSTANDING ANYTHING HEREIN TO THE CONTRARY, IN THE CASE OF THE EXPANDED EXISTING REGION (A) NEITHER PARTY SHALL HAVE ANY LIABILITY TO THE OTHER PARTY FOR DAMAGES AND (B) NO ADJUSTMENTS SHALL BE MADE PURSUANT TO SECTION 12.2(i), IN EITHER CASEDUE TO THE PROVISION OF INACCURATE PRICING OR DISCOUNT INFORMATION TO THE DISCOUNT COMMITTEE (OR, FOR ANY CALENDAR QUARTER UP TO AND INCLUDING THE [*]), EXCEPT TO THE EXTENT THAT SUCH BREACH OR LACK OF COMPLIANCE AROSE FROM THE GROSS NEGLIGENCE OR INTENTIONAL MISCONDUCT OF SUCH PARTY OR ITS AFFILIATES.

(ii)    NOTWITHSTANDING ANYTHING HEREIN TO THE CONTRARY, IN THE CASE OF LIMITED REGION A, REGION B AND REGION C (A) THE SELLING PARTY SHALL HAVE NO LIABILITY TO THE NON-SELLING PARTY FOR DAMAGES AND (B) [*].

SECTION 37.Adjustments. Section 12.2(i) of the Agreement is hereby replaced in its entirety with the following:

(i)    Adjustments.

(i)The following shall apply to the Expanded Existing Region: Except as otherwise provided in Section 12.2(e), in the event that the Independent Accounting Expert determines, pursuant to this Section 12.2, that any Party provided any inaccurate information, the Parties shall coordinate to recalculate any amounts due hereunder or under any Ancillary Agreement based on the corrected data, as

provided by the Independent Accounting Expert, and to make any payments that may be required to ensure that costs and expenses and revenues are shared in accordance with such recalculations (and the other applicable terms of this Agreement or such Ancillary Agreement); provided, however, that if either Party provided inaccurate pricing or discount information to the Discount Committee (or, for any Calendar Quarter up to and including the [*] due to its or any of its Affiliates' gross negligence or intentional misconduct, and such inaccurate information (or non-compliant DCP) resulted in a higher selling price for the Combination Product than would have been permitted hereunder had the proper information (or DCP) been provided, then with respect to any Triggering Sales of Combination Product that were sold at a higher price that reflected such inaccurate price information of such Party (or non-compliant DCP), the Parties' respective revenue shares shall be adjusted as follows: the Selling Party shall determine, for the Units of Combination Product sold in such Triggering Sales (the “At-Issue Units”), (a) [*]. Other than the foregoing reapportionment, no other adjustments are intended to be made to account for, or as a result of, the Corrected Revenue Share (e.g., no adjustments to the Actual Percentages).

(ii)The following shall apply to the Limited Region A, Region B and Region C: Except as otherwise provided in Section 12.2(e), in the event that it is determined, pursuant to this Section 12.2, that any Party provided any inaccurate information, the Parties shall coordinate to recalculate any amounts due hereunder or under any Ancillary Agreement based on the corrected data, as has been determined pursuant to this Section 12.2, and to make any payments that may be required to ensure that costs and expenses and revenues are shared in accordance with such recalculations (and the other applicable terms of this Agreement or such Ancillary Agreement)

SECTION 38.Trademark Registration Costs. Section 14.6(c)(i) of the Agreement is hereby replaced in its entirety with the following:

14.6(c)(i)    Registration. Subject to the licenses granted in Section 9.4(c), the Parties agree that, as between Gilead and Janssen and their respective Affiliates, Gilead (or its designee) shall own all right, title and interest in and to the Combination Product Trademarks. Gilead (or its designee) shall have the sole right, at its sole expense, to search, clear, file, register, prosecute and maintain the Combination Product Trademarks anywhere in the world in the name of Gilead (or its designee); provided, however, that [*].

SECTION 39.Additional Representations, Warranties and Covenants.

39.1.Section 17.1(l) of the Agreement is hereby replaced in its entirety as follows:

(a)Cooperation with In-License Agreement Compliance. Such Party, at the request of the other Party, will reasonably cooperate with such other Party, including by complying with Annex W, to enable the other Party (or any of its Affiliates) to comply with such other Party's obligations under any agreement between such other Party or its Affiliate, on the one hand, and a Third Party, on the other hand, pursuant to which such other Party or such Affiliate obtained from such Third Party a license or similar grant of rights with respect to any of (i) in the case of Gilead as the other Party, the Gilead Patents, and (ii) in the case of Tibotec as the other Party, the Tibotec Patents (each such agreement, an “In-License Agreement”). Each Party acknowledges that if the failure by a Party to provide such reasonable cooperation to the other Party results in a breach of such agreement, such failure to cooperate may give rise to a termination right by the Third Party that is party to the In-License Agreement.

39.2.Section 17.2(a) of the Agreement is hereby amended by:

(a)Deleting from the Section the following text “; provided, that this sentence shall not apply to Japan or any of the countries in the Access Territory from and after [*] or for such longer period as

Gilead is negotiating in good faith with Janssen to enter into an agreement with respect to the Commercialization of the Combination Product in Japan or such Access Territory country, as the case may be”; and

(b)Inserting in place of the deleted text the following text “; provided, however, that Janssen and its Affiliates shall not be precluded by the foregoing from granting licenses or other rights under their intellectual property to allow any generic manufacturer to Exploit, solely in and for sale in one or more countries in Region C, Combination Product; provided that the agreement between such generic manufacturer and Janssen or its applicable Affiliate granting such rights complies with Sections 17.2(d) and (e) (the right to grant such licenses to generic manufacturers described in this Section 17.2(a) and the analogous right of Gilead under Section 17.3(c) are collectively, the 'Generic Exception').”

39.3.A new Section 17.2(d) of the Agreement is hereby inserted as follows:

Requirements for Janssen Licensees. For (x) each Janssen Licensee that enters into an agreement with Janssen following the Second Amendment Effective Date, Janssen shall ensure such agreement includes, by way of a covenant or a condition on or limitation in the scope of the rights or licenses granted, each of the following provisions (or substantially similar or more restrictive provisions) and (y) each current Janssen Licensee, [*]:

(i)All Generic Region C Combination Product manufactured by the Janssen Licensees shall only be manufactured in facilities located in Region C or, at Janssen's discretion, a subset of countries contained within Region C.

(ii)The Janssen Licensee shall not sell and shall prohibit its Affiliates, distributors and their respective wholesalers and distributors from selling any Generic Region C Combination Product outside of Region C or from assisting any Third Party in doing so.

(iii)The Janssen Licensee shall use a trade dress for the Generic Region C Combination Product that has a tablet color, embossing and printing on the tablet and packaging that is sufficiently different than both the Major Market Trade Dress and the Branded Region B/C Trade Dress so that there will be no likelihood of confusion. Janssen shall review and approve exemplars of each Generic Region C Combination Product to be Manufactured by the Janssen Licensees to ensure compliance with this subsection.

39.4.A new Section 17.2(e) of the Agreement is hereby inserted as follows:

Janssen shall as soon as reasonably possible, and [*].

SECTION 40. Additional Representations, Warranties and Covenants of Gilead.

40.1.Section 17.3(c) of the Agreement is hereby amended by:

(a)Deleting from the Section the following text “; provided, that this sentence shall not apply to Japan or any of the countries in the Access Territory from and after [*] or for such longer period as Gilead is negotiating in good faith with Janssen to enter into an agreement with respect to the Commercialization of the Combination Product in Japan or such Access Territory country, as the case may be”; and

(b)Inserting in place of the deleted text the following text “; provided, however, that Gilead and its Affiliates shall not be precluded by the foregoing from granting licenses or other rights under their

intellectual property to allow any generic manufacturer to Exploit, solely in and for sale in one or more countries in Region C, Combination Product or Derivative Combination Product, provided that the agreement between such generic manufacturer and Gilead or its applicable Affiliate granting such rights complies with Sections 17.3(d) and (e).

40.2.A new Section 17.3(d) of the Agreement is hereby inserted as follows:

Requirements for Gilead Licensees.  For (x) each Gilead Licensee that enters into an agreement with Gilead following the Second Amendment Effective Date, Gilead shall ensure such agreement includes, by way of a covenant or a condition on or limitation in the scope of the rights or licenses granted, each of the following provisions (or substantially similar or more restrictive provisions) and (y) each current Gilead Licensee, [*]:

(i)All Generic Region C Combination Product manufactured by the Gilead Licensees shall only be manufactured in facilities located in Region C or, at Gilead's discretion, a subset of countries contained within Region C.

(ii)The Gilead Licensee shall not sell and shall prohibit its Affiliates, distributors and their respective wholesalers and distributors from selling any Generic Region C Combination Product outside of Region C or from assisting any Third Party in doing so. 

(iii)The Gilead Licensee shall use a trade dress for the Generic Region C Combination Product that has a tablet color, embossing and printing on the tablet and packaging that is sufficiently different than both the Major Market Trade Dress and the Branded Region B/C Trade Dress so that there will be no likelihood of confusion.  Gilead shall review and approve exemplars of each Generic Region C Combination Product to be Manufactured by the Gilead Licensees to ensure compliance with this subsection.

40.3.A new Section 17.3(e) of the Agreement is hereby inserted as follows:

17.3(e)        Gilead shall as soon as reasonably possible, and [*].

SECTION 41.Consequences of Termination.

Section 19.6(d)(vi) is hereby amended by inserting “, Annex Y” following the words “Section 7”.

SECTION 42.Survival. Section 19.7(b) of the Agreement is hereby amended and replaced in its entirety with the following:

19.7(b)    Without limiting anything contained in Section 19.6, in the event of any termination of this Agreement for any reason, this Section 19.7 and Sections 1, 2.4, 3.4, 3.6 , 4.5, 6.1(a)(i), 6.1(a)(ii), 7 (to the extent relating to the calculation of the Parties' respective share of revenue from the sale of the Territory Combination Product that contains Supplied TMC278 shipped to Gilead (or its Affiliate) in the Expanded Existing Region during the term of this Agreement), 7.2(a) through (c) (to the extent relating to preventing the unauthorized use and disclosure of a Party's Territory Pricing Information), 7.4(c), 7.4(g), 8 (to the extent relating to payment by Gilead to Janssen for TMC278 API shipped to Gilead (or its Affiliate) during the term of this Agreement), 9.1(a)(iii), 9.1(b)(ii), 9.3(c) (to the extent relating to 9.1(a)(iii) and 9.1(b)(ii)), 9.4(d), 9.5 (only the first sentence and the last two sentences),10.2, 10.3 (solely with respect to any adjustments to the payment obligations that have accrued prior to the effective date of termination), 10.5 through 10.11, 10.12 (solely with respect to any royalties payable with respect to Territory Combination Product sold by the Selling Party or its Affiliates during the period in which Janssen is

supplying Supplied TMC278 under the TMC278 Supply Agreement), 11.1, 11.5 through 11.7 (to the extent relating to payment by Gilead to Janssen for TMC278 API shipped to Gilead (or its Affiliate) or relating to payment by Janssen to Gilead for Territory Combination Product Delivered to Janssen (or its Affiliate), in each case during the term of this Agreement) during the term of this Agreement), 11.8 (solely for purposes of a final yield adjustment), 11.9 (solely for the purposes of final calculations under this Agreement, 11.10 (solely for the purposes of final calculations under this Agreement), 12, 13 (to the extent the matters described therein are reasonably likely to affect the Territory Combination Product), 14.1, 14.3, 14.4(d) and (f), 14.5 (other than the last sentence of 14.5), 14.6(a) through (c)(i), 15, 16.3 (solely as the matters prohibited therein relate to this Agreement), 17 (solely with respect to the representations and not with respect to any covenants set forth therein), 17.4, 18, 19.6, 20.1 through 20.15 and the Annexes to the extent applicable to the other surviving terms of this Agreement, shall survive such termination (with respect to the terminated Region, if applicable). For the avoidance of doubt, the survival of certain terms of Annex Z are set forth in Annez Z.

SECTION 43.Annexes I, L, M, N, Q, R, W, and Y. Each of Annexes I, L, M, N, Q, R, W, and Y are hereby replaced in their entirety with the attached Exhibits I, L, M, N, Q, R, W, and Y, respectively.

SECTION 44.Annex Y: Region A, Region C and Region B Alternate Pricing and Discount Rules. Annex Y of the Agreement is hereby inserted with the attached Exhibit Y.

SECTION 45.Annex Z: Territory Combination Product Supply to Janssen. Annex Z of the Agreement is hereby inserted with the attached Exhibit Z.

SECTION 46.Annex AA: Selling Party and Regions. Annex AA of the Agreement is hereby inserted with the attached Exhibit AA.

SECTION 47.Annex BB: Invoices and Payment Terms for Janssen Countries. Annex BB of the Agreement is hereby inserted with the attached Exhibit BB.

SECTION 48.Annex CC: Exchange Rates and Currency Conversion True-Up Principles. Annex CC of the Agreement is hereby inserted with the attached Exhibit CC.

SECTION 49.Annex DD: Calendar Year End Revaluation TCP Invoices. Annex DD of the Agreement is hereby inserted with the attached Exhibit DD.

SECTION 50.Annex EE: Letter Agreement Regarding Marketing Authorization for Combination Product. Annex EE of the Agreement is hereby inserted with the attached Exhibit EE.

SECTION 51.Definitions. All capitalized terms used, but not defined, in this Amended and Restated Second Amendment shall have their respective meanings set forth in the Agreement.

SECTION 52.Construction. The principles set forth in Section 20.12 of the Agreement shall apply to this Amended and Restated Second Amendment.

SECTION 53.Effective Date; Incorporation of Terms; Continuing Effect. This Amended and Restated Second Amendment shall be deemed effective for all purposes as of the Second Amendment Effective Date. The amendment set forth in this Amended and Restated Second Amendment shall be deemed to be incorporated in, and made a part of, the Agreement, and the Agreement, the First Amendment and this Amended and Restated Second Amendment shall be read, taken and construed as one and the same agreement (including with respect to the provisions set forth in Section 20 (Miscellaneous) of the Agreement which shall, as applicable, be deemed to apply to this Amended and Restated Second

Amendment (including with respect to the governing law). Except as otherwise expressly amended by this Amended and Restated Second Amendment, the Agreement shall remain in full force and effect in accordance with its terms and conditions.

SECTION 54.Counterparts. This Amended and Restated Second Amendment may be executed in any number of counterparts, each of which shall be deemed to be an original, and all of which, taken together, shall constitute one and the same instrument.

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IN WITNESS WHEREOF, the parties, intending to be bound, have caused this Amended and Restated Second Amendment to be executed on their behalf by their duly authorized agent as of the day and year first above written.

JANSSEN R&D IRELAND
By:	/s/ Margaret Dunlea Name: Margaret Dunlea Title: Managing Director           Janssen R&D Ireland

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Signature Page to Amended and Restated Second Amendment

GILEAD SCIENCES, INC.
By:	/s/ John F. Milligan Name: John F. Milligan, Ph.D. Title: President and Chief Operating Officer
GILEAD SCIENCES LIMITED
By:	/s/ John F. Milligan Name: John F. Milligan, Ph.D. Title: Director

Signature Page to Amended and Restated Second Amendment

I. Annex I: Calculation of Actual Percentages

II. Annex L: Annual Adjustments to Account for Actual Yield

III. Annex M: Payment Terms for TMC278 Invoices

IV. Annex N: Post-Conversion Supply Price

V. Annex Q: Additional Financial Reporting

VI. Annex R: Discount Rules and Related Matters

VII. Annex W: In-License Agreement Compliance

VIII. Annex Y: Limited Region A, Region B and Region C Pricing and Discounts

IX. Annex Z: Territory Combination Product Supply to Janssen

X. Annex AA: Selling Party and Country List for Region A, Region B and Region C

XI. Annex BB: Invoice and Payment Terms for Territory Combination Product in Janssen Countries

XII. Annex CC: Exchange Rates and Currency Conversion True-Up Principles

XIII. Annex DD: Calendar Year End Invoice Adjustment for Janssen Countries

XIV. Annex EE: Letter Agreement Regarding Marketing Authorization for Combination Product.

I. Annex I: Calculation of Actual Percentages

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”).

For each Calendar Year, (a) an actual percentage for each Party shall be established for the Territory as a whole (each an “Actual Percentage”) in accordance with this Annex I and (b) an actual percentage for each Party shall be established on a Regional basis (as described below) in accordance with this Annex I (each a “Regional Actual Percentage”).

For each Calendar Year, up to and including the Calendar Year prior to the Calendar Year in which the first Launch of the Territory Combination Product in the Territory occurs, the Actual Percentage of Gilead shall equal the Working Percentage of Gilead for such Calendar Year and the Actual Percentage of Janssen shall equal the Working Percentage of Janssen for such Calendar Year and for such period each Regional Actual Percentage of each Party shall equal the Actual Percentage of such Party.

For each Calendar Year from and after the Calendar Year in which the first Launch of the Combination Product in the Territory occurs:

A. Territory-Wide Percentages.

For a given Calendar Year, the Actual Percentage of Janssen shall [*]. The Actual Percentage of Gilead shall equal one hundred percent (100%) less the Actual Percentage of Janssen for such Calendar Year, i.e.:

100% - Actual Percentage of Janssen for such Calendar Year

The Actual Percentages shall be calculated by Gilead and notified to Janssen no later than January 31st of such Calendar Year.

B. Regional Percentages

B.1. Expanded Existing Region

The Regional Actual Percentage of Janssen for the Expanded Existing Region shall equal [*]:

[*]

[*]

The Regional Actual Percentage of Gilead for the Expanded Existing Region shall equal one hundred percent (100%) less the Regional Actual Percentage of Janssen for such Region for such Calendar Year, i.e.:

100% - Regional Actual Percentage of Janssen for such Calendar Year

Such Regional Actual Percentages shall be calculated by Gilead and notified to Janssen no later than January 31st of such Calendar Year.

B.2. Limited Region A, Region B and Region C.

For each of the Limited Region A, Region B and Region C, the Regional Actual Percentage [*].

An example of the calculation of the Actual Percentages and Regional Actual Percentages as described above, provided for illustrative purposes only, is set forth below.

[*]

II. Annex L: Annual Adjustments to Account for Actual Yield

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”).

1. At the end of each Calendar Year, Gilead shall determine [*], Gilead shall use reasonable efforts to provide such determinations to Janssen by February 15 after the end of the applicable Calendar Year and shall provide such determinations no later than March 1 after the end of such Calendar Year.

2. For each Calendar Year, no later than thirty (30) days after the applicable notification is provided pursuant to Paragraph 1 of this Annex L, (a) [*].

3. For clarification, there shall be [*].

An example of the calculation of the Quantity Differential and associated Calendar Year-end balance sheet adjustments pursuant to paragraph 2 above (as if it were a single Region), provided for illustrative purposes only, is attached below.

[*]

III. Annex M: Payment Terms for TMC278 Invoices

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”). The payment terms for each of the Regions, for the applicable Party are as follow:

A. Gilead Countries in the Expanded Existing Region

For the avoidance of doubt, references to the Region in this Section A are deemed to mean the Gilead Countries in the Expanded Existing Region.

A.1. Determination of the Annual Forecast Payment Term

No later than November 15th of each Calendar Year (in conjunction with the establishment of the Pre-Conversion Supply Price), Gilead shall propose, for the upcoming Calendar Year with respect to the Gilead Countries of the Region a payment term for the payment of TMC278 Invoices (the “Annual Forecast Payment Term”) in the Region. Gilead shall provide Janssen with a basis for its proposed payment term, which shall reflect [*].

In the event that agreement on the Annual Forecast Payment Term for the Gilead Countries in the Region cannot be reached by the Parties for a given Calendar Year by the commencement of such Calendar Year, the Annual Forecast Payment Term for such Calendar Year shall be [*] (the “Annual Default Payment Term”). Gilead shall calculate and promptly notify Janssen of the Annual Default Payment Term for the Region.

The Default Payment Terms and the TPD Default Payment Terms shall be determined as follows for the Region:

1) On a country-by-country basis, for each Gilead Country [*] (each a “Default Payment Term”). Gilead shall promptly notify Janssen of the Default Payment Term for each applicable country, once calculated.

2) On a country-by-country basis, for each Gilead Country [*] (each a “TPD Default Payment Term”).

A.2. Deviation from Annual Forecast Payment Term.

On a quarterly basis for the Region, Gilead shall calculate and report to Janssen [*]

A.3. Payment Terms

a) TMC278 Invoices.

For any Triggering Sales of Territory Combination Product that occur in a given calendar month in the Region, any corresponding (as determined below) TMC278 Invoices (or portions thereof) shall be due [*]

B. Limited Region A Gilead Countries

[*]

An example of the calculation of the payment term with respect to the Gilead Countries in Limited Region A is included below:

[*]

C. Region B and Region C Gilead Countries

The term “Region” as used in this Section C shall refer to the Gilead Countries in both Region B and Region C collectively. [*].

D. Region A, Region B and Region C Janssen Countries

For a given month, for any (a) Triggering Sales with respect to Territory Combination Product sold under an Interim TCP Invoice for Region A Janssen Countries; or (b) Delivery (as defined in Annex Z) of Territory Combination Product to Janssen for Region B or Region C Janssen Countries under an Interim TCP Invoice, Gilead shall establish due dates for the Pre-Conversion Invoices corresponding to such Interim TCP Invoice [*].

IV.    Annex N: Post-Conversion Supply Price

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”). The Post-Conversion Supply Price for the applicable Region and Selling Party shall be as follows:

A. The Gilead Countries in the Expanded Existing Region

For purposes of this Section A, Region shall mean the Gilead Countries in the Expanded Existing Region. The Post-Conversion Supply Price [*]

An example of the calculation of the Post-Conversion Supply Price and the Additional Supply Price, provided for illustrative purposes only, is set forth below.

[*]

An example of the revenue share report for the United States provided for illustrative purposes only, is set forth below.

[*]

B. Janssen Countries

For the avoidance of doubt, [*]

C. Gilead Countries in Limited Region A, Region B and Region C

The term “Region” as used in this Section C shall refer to (i) the Gilead Countries in Limited Region A and (ii) the Gilead Countries in both Region B and Region C collectively. For the avoidance of doubt, [*]

C.1. Post-Conversion Supply Price

The Post-Conversion Supply Price for a given Calendar Year (per kilogram of Supplied TMC278) with respect to the applicable Region shall equal:

[*]

An example of the calculation of the Post-Conversion Supply Price based on certain estimates with respect to TMC278 in the Gilead Countries in the Limited Region A is included below.

[*]

C.2. Regional TMC278 Annual True-Up

The following Regional TMC278 Annual True-Up shall be calculated [*]

An example of the calculation of Regional Actual Net Selling Price and the Regional TMC278 Annual True-Up in the Limited Region A is included below.

[*]

V.    Annex Q: Additional Financial Reporting

Capitalized terms used in this Annex and not defined herein shall have the meaning set forth in the agreement to which this Annex is attached (the “Agreement”). Section references used in this Annex shall refer to Sections in the Agreement except as otherwise provided.

I. Review of Calculations. Without limitation of a Party's audit rights under Sections 12.2(b) and (c) of the Agreement, each Party may review any calculation provided by the other Party under this Annex Q with respect to the Limited Region A, Region B and Region C. If the reviewing Party disagrees with the other Party's calculations, the reviewing Party shall promptly notify the other Party and the Parties' respective finance representatives shall confer to discuss such disagreement. If they are unable to resolve such dispute within ten (10) Business Days, to the extent such dispute regards the calculation itself (rather than a dispute regarding an interpretation of the Agreement (including this Annex or any other Annexes) or those matters covered by Section 12.2(b) or (c)), then the reviewing Party may refer such dispute to an Independent Accounting Expert. The determination of such Independent Accounting Expert shall be deemed binding upon the Parties absent an agreement to the contrary. For clarity, any dispute regarding the interpretation of the Agreement (including this Annex or any other Annexes) shall be subject to the dispute resolution provisions set forth in the Agreement. For the avoidance of doubt, this provision is intended to apply only to review of the calculations performed pursuant to this Annex Q, and shall not entitle either Party to audit the underlying information utilized in such calculations, which audit right is exclusively provided pursuant to Section 12.2(b) and (c) of the Agreement.

II. Expanded Existing Region. This Section II applies only with respect to the Expanded Existing Region. The Parties shall exchange information as follows:

Each Party shall provide the other Party with the following information at the times set forth below. Reporting pursuant to Section II of this Annex Q shall be on a country-by-country basis and, where appropriate in light of the calculations to be made under the Agreement or any Ancillary Agreements, in the aggregate for all countries reported by the applicable Party in the Expanded Existing Region. Furthermore, to the extent applicable to the reporting contemplated in Section II of this Annex Q, the Parties shall coordinate in good faith to establish categories into which the reporting Party may group Customers based on discounts and other factors deemed relevant by the Parties (“Customer Groups”) in order to limit the level of administrative burden to the Selling Party, and such Customer Groups may change from time to time as the result of changes in Customers' respective discounts or changes in such other factors. Once agreed by the Parties, such Customer Groups may be used by Gilead for purposes of determining the Post-Conversion Supply Price pursuant to Annex N for the Expanded Existing Region.

A.[*]

VI.    Annex R: Discount Rules and Related Matters

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”). “Representative” shall mean, with respect to a Party, either the Business Representative or the Attorney Representative of such Party.

[*]

VII.    Annex W: In-License Agreement Compliance

[*]

* The entity, Tibotec Pharmaceuticals, was formerly Tibotec Pharmaceuticals Limited.

VIII.    Annex Y: Limited Region A, Region B and Region C Pricing and Discounts

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”).

A. Generally.

The provisions set forth in this Annex Y shall apply to the pricing of Territory Combination Product sold by the Selling Party or any of its applicable Affiliates to any Third Party, including a Third Party Distributor, in any country outside the Expanded Existing Region. For clarity, the Discount Committee described in Section 7 of the Agreements shall not govern the pricing activities under this Annex Y.

B. Pricing Principles Outside the Expanded Existing Region.

1. The Selling Party shall have discretion as to the price that it offers to sell the Territory Combination Product unless otherwise specifically provided in this Annex Y. Except as otherwise agreed by the Parties in writing, with respect to any Price Approval Country, the Selling Party shall be responsible for managing the negotiation with the applicable authority(ies) in each such country in the Territory to obtain and maintain pricing approval.

2. Upon request of one Party, the other Party shall make available to such requesting Party, solely to the extent allowed by Applicable Law, such information Controlled by such other Party and its Affiliates as is required in order to obtain pricing and reimbursement approvals for the Territory Combination Product.

3. The following shall apply to Price Approval Countries in Limited Region A or Region B. If, following the Launch of the Territory Combination Product in a given Price Approval Country, [*]

4. As between the Parties (and their respective Affiliates), the Selling Party (and its Affiliates) (or its Third Party Distributor) shall have sole responsibility for conducting pricing and discounting negotiations (and all other contracting matters) with respect to the Territory Combination Product with Customers in the applicable country in the Territory in accordance with this Annex Y.

5. Gilead and Janssen shall each retain sole discretion with respect to price-setting and discounts for its respective Single Agent Products and Double Agent Product. Notwithstanding the foregoing, [*]

C. Disputes.

In the event that interpretation or application of this Annex Y is necessary to implement the provisions of this Annex Y, the Alliance Managers shall discuss the matter and attempt to resolve the matter by consensus.

To the extent any of the above procedures is not permitted by Applicable Law, the Parties shall promptly agree on alternative procedures to replace such procedures.

IX.    Annex Z: Territory Combination Product Supply to Janssen

[See Separate Document]

X.    Annex AA: Selling Party and Country List for Region A, Region B and Region C

This list shall automatically include any country that is derived from the territory of a country listed below (for example, the independent country of Southern Sudan from Sudan).

Region A
Country	Selling Party
Albania	Gilead
Argentina	Janssen
Bahrain	Janssen
Bosnia-Herzegovina	Gilead
Chile	Gilead
Colombia	Gilead
Costa Rica	Gilead
Hong Kong	Janssen
Israel	Janssen
Japan	Janssen
Kosovo	Gilead
Kuwait	Janssen
Lebanon	Janssen
Macau	Janssen
Malaysia	Janssen
Mexico	Janssen
Montenegro	Gilead
Oman	Janssen
Qatar	Janssen
Russia	Janssen
Saudi Arabia	Janssen
Serbia	Gilead
Singapore	Janssen
South Korea	Janssen
Taiwan	Janssen
United Arab Emirates	Janssen
Uruguay	Gilead
Venezuela	Gilead

Region B
Country	Selling Party
Algeria	Janssen
Azerbaijan	Janssen
Belarus	Janssen
Cayman Islands	Gilead
Curacao	Gilead
China (Mainland)	Janssen
Egypt	Janssen
Iran	Janssen
Iraq	Janssen
Jordan	Janssen
Libya	Janssen
Morocco	Janssen
Panama	Gilead
Paraguay	Gilead
Peru	Gilead
Philippines	Janssen
Sint Maarten	Gilead
Tunisia	Janssen
Ukraine	Janssen

Region C
Country	Selling Party
Afghanistan	Janssen
Angola	Janssen
Anguilla	Gilead
Antigua and Barbuda	Gilead
Armenia	Janssen
Aruba	Gilead
Bahamas	Gilead
Bangladesh	Janssen
Barbados	Gilead
Belize	Gilead
Benin	Janssen
Bhutan	Janssen
Bolivia	Gilead
Botswana	Janssen
British Virgin Islands	Gilead
Burkina Faso	Janssen
Burundi	Janssen
Cambodia	Janssen
Cameroon	Janssen
Cape Verde	Janssen
Central African Republic	Janssen
Chad	Janssen
Comoros	Janssen
Congo	Janssen
Congo, Dem. Rep. of the	Janssen
Cote d'Ivoire	Janssen
Cuba	Gilead
Djibouti	Janssen
Dominica	Gilead
Dominican Republic	Gilead
Ecuador	Gilead
El Salvador	Gilead
Equatorial Guinea	Janssen
Eritrea	Janssen
Ethiopia	Janssen
Fiji	Janssen
Gabon	Janssen
Gambia	Janssen
Georgia	Janssen
Ghana	Janssen
Grenada	Gilead
Guatemala	Gilead
Guinea	Janssen
Guinea-Bissau	Janssen
Guyana	Gilead
Haiti	Gilead
Honduras	Gilead

India	Janssen
Indonesia	Janssen
Jamaica	Gilead
Kazakhstan	Janssen
Kenya	Janssen
Kiribati	Janssen
Korea, Dem. People's Rep of	Janssen
Kyrgyzstan	Janssen
Lao, People's Dem. Rep.	Janssen
Lesotho	Janssen
Liberia	Janssen
Madagascar	Janssen
Malawi	Janssen
Maldives	Janssen
Mali	Janssen
Mauritania	Janssen
Mauritius	Janssen
Moldova, Rep. of	Janssen
Mongolia	Janssen
Montserrat	Gilead
Mozambique	Janssen
Myanmar	Janssen
Namibia	Janssen
Nauru	Janssen
Nepal	Janssen
Nicaragua	Gilead
Niger	Janssen
Nigeria	Janssen
Pakistan	Janssen
Palau	Janssen
Papua New Guinea	Janssen
Rwanda	Janssen
Saint Kitts and Nevis	Gilead
Saint Lucia	Gilead
Saint Vincent and the Grenadines	Gilead
Samoa	Janssen
Sao Tome and Principe	Janssen
Senegal	Janssen
Seychelles	Janssen
Sierra Leone	Janssen
Solomon Islands	Janssen
Somalia	Janssen
South Africa	Janssen
South Sudan	Janssen
Sri Lanka	Janssen
Sudan	Janssen
Suriname	Gilead
Swaziland	Janssen
Syria	Janssen
Tajikistan	Janssen

Tanzania, U. Rep. of	Janssen
Thailand	Janssen
Timor-Leste	Janssen
Togo	Janssen
Tonga	Janssen
Trinidad and Tobago	Gilead
Turkmenistan	Janssen
Turks and Caicos	Gilead
Tuvalu	Janssen
Uganda	Janssen
Uzbekistan	Janssen
Vanuatu	Janssen
Vietnam	Janssen
Yemen	Janssen
Zambia	Janssen
Zimbabwe	Janssen

XI. Annex BB: Invoice and Payment Terms for Territory Combination Product in Janssen Countries

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”).

Gilead shall issue to Janssen an Interim TCP Invoice upon shipment of Territory Combination Product pursuant to the Janssen Distributor Agreement. Each such Interim TCP Invoice shall state the invoiced amount and quantity of Territory Combination Product covered by such invoice. Janssen shall pay each such Interim TCP Invoice in accordance with the payment terms and calculations set forth in this Annex BB of the Agreement.

[*]

A. Janssen Country Combination Product Invoicing

All TCP Invoices shall be issued and paid in U.S. Dollars on the date set forth below.

A.1. Invoicing and Payment in Region A Janssen Countries

For purposes of this section the Janssen Countries in Region A are collectively the “Region” for purposes of this Section A.1, such that there shall be a single Average Janssen Region Payment Term for all of the Janssen Countries in Region A.

[*]

An example of the calculation of the payment term with respect to the Janssen Countries in Region A is included below.

[*]

[*]

A. Janssen Country Combination Product Interim Supply Price

[*]

An example of the calculation of the TCP Interim Supply Price with respect to Territory Combination Product in Region A Janssen Countries (excluding [*]) is included below.

[*]

B.1. Region B and Region C Janssen Countries

During a Calendar Year, Gilead shall supply each Unit of Branded Region B/C Combination Product to Janssen or its designated Affiliate at the TCP Interim Supply Price calculated for the Region B and Region C Janssen Countries (collectively, the Janssen Countries of Region B and Region C shall constitute a “Region” for purposes of this Section B.2) during such Calendar Year.

[*]

[*]

C. Janssen Country Combination Product Annual True-Up

C.1. Region A Janssen Countries Excluding [*]

Within ninety (90) days following the end of each Calendar Year, Gilead shall provide Janssen with a Final TCP Invoice with respect to each Interim TCP Invoice (or portion thereof) for the Janssen Countries in Region A (excluding [*]) (collectively, the “Region” for purposes of this Section C.1). [*]

An example of the calculation of the TCP Annual True-Up is included below.

[*]

C.2. Region B and Region C Janssen Countries

The following TCP Annual True-Up calculations shall be calculated collectively for the Janssen Countries of Region B and Region C (which are collectively the “Region” for purposes of this Section C.2) such that there shall be a single TCP Annual True-Up for Region B and Region C.

Within ninety (90) days following the end of each Calendar Year, Gilead shall provide Janssen with a Final TCP Invoice with respect to each Interim TCP Invoice (or portion thereof) for the Region. [*]

XII.    Annex CC: Exchange Rates and Currency Conversion True-Up Principles

Capitalized terms not defined in this Annex shall have the meanings set forth in the agreement to which this Annex is attached (the “Agreement”).

A. Estimated Net Selling Price and TCP Interim Supply Price Currency Conversions

With respect to the calculation of the TMC278 Post-Conversion Supply Price in Annex N with respect to the Limited Region A, Region B and Region C and the TCP Interim Supply Price in Annex BB with respect to the Janssen Countries and the calculations associated therewith, the conversion of currency values used in such calculations with respect to a country from the local currency into U.S. Dollars shall be calculated utilizing the applicable Intra-Year Conversion Rate for such country during such Calendar Year.

“Intra-Year Conversion Rate” shall mean, with respect to a Calendar Year and a country, the daily exchange rate between the applicable country's currency and U.S. Dollars reported by the Bloomberg Professional service application on the last Business Day during the month of October in the previous Calendar Year.

B. Regional TMC278 Annual True-Up and TCP Annual True-Up

Notwithstanding Section 10.9 of the Agreement and except as otherwise specified in Annex BB Section C.1 with regard to the DCP and Combination Product Actual Net Selling Price values in Argentina, Mexico and Russia, with respect to the calculation of the Regional TMC278 Annual True-Up in Annex N and the TCP Annual True-Up in Annex BB, the conversion of currency values used in such calculations with respect to a country from the local currency into U.S. Dollars shall be calculated utilizing the applicable Final Year Conversion Rate for such country for such Calendar Year with respect to which the Regional TMC278 Annual True-Up and TCP Annual True-Up, as applicable, is being calculated.

“Final Year Conversion Rate” shall mean, with respect to a Calendar Year and a country, the weighted average of the applicable country's Monthly Average Exchange Rate for each of the months in such Calendar Year, weighted by the corresponding Actual Unit Sales, as applicable, with respect to such country for such calendar month.

“Monthly Average Exchange Rate” shall mean, with respect to a country and a calendar month, the actual average daily exchange rate for such month for converting the applicable country's currency into U.S. Dollars, as such rate is reported in Bloomberg Professional service application.

“Actual Unit Sales” shall mean, with respect to a country and a calendar month, the actual number of Units of Territory Combination Product for which a Triggering Sale by Gilead and its Affiliates or Janssen and its Affiliates, as applicable, has occurred in such country for such calendar month.

An example of the calculation of the Final Year Conversion Rate for the TCP Annual True-Up in the Janssen Countries is included below.

[*]

XIII.    Annex DD: Calendar Year End Invoice Adjustment for Janssen Countries

For purposes of this Annex DD, “Region” shall be deemed to mean each of (a) Region A (excluding [*]), (b) Region B and Region C collectively (such that there shall be one calculation for all Janssen Countries in Region B and Region C) and (c) [*]

An example of the calculation of the Revaluation TCP Invoice with respect to the Janssen Countries is included below.

[*]

XIV. Annex EE: Letter Agreement Regarding Marketing Authorization for Combination Product.

February 7, 2013

John F. Milligan, Ph.D.

President and Chief Operating Officer

Gilead Sciences, Inc.

333 Lakeside Drive

Foster City, CA  94404

Re: Marketing Authorization Holder for Combination Product

Dear Dr. Milligan,

Janssen R&D Ireland (formerly known as Tibotec Pharmaceuticals), Gilead Sciences Limited, and Gilead Sciences, Inc. entered into a License and Collaboration Agreement, dated as of July 16, 2009 (as amended, the “Agreement”) relating to the development and commercialization of the Combination Product in the Field. (Capitalized terms used, but not defined, in this letter shall have their respective means set forth in the Agreement.)

In accordance with Section 4.4(a) of the Agreement, Gilead, or its designated Affiliate or Third Party Distributor, shall hold the marketing authorization with respect to the Combination Product with respect to each country in the Territory, unless otherwise agreed to in writing by the Parties or prohibited by Applicable Law.

The Parties hereby agree that Janssen, or its designated Affiliate or Third Party Distributor, will hold the marketing authorization with respect to the Combination Product in the countries listed in Attachment 1 attached hereto. For clarity, the Parties agree that Janssen is the Selling Party for the Combination Product in Russia and China (Mainland), but Gilead, or its designated Affiliate or Third Party Distributor, shall hold the marketing authorization with respect thereto in Russia and the Import Drug License (IDL) with respect thereto in China (Mainland).

This letter shall be subject in all respects to the terms and conditions of the Agreement. In the event of any conflict between the provisions of this letter and the provisions of the Agreement, the provisions of the Agreement shall control except with respect to the identification of the MA Holder, paragraph 3 of this letter shall control.

If you are in agreement with the principles set forth in this letter, please sign and return the enclosed copy to my attention.

Gilead Sciences Inc.

/s/ John F. Milligan_________

(Signature)

By: John F. Milligan, Ph.D.

Title: President and Chief Operating Officer

Date: ___________________

Janssen R&D Ireland

/s/ Margaret Dunlea_________

(Signature)

By: Margaret Dunlea

Title: Managing Director, Janssen R&D Ireland

Date: ___________________

Attachment 1

Region A

Country

Argentina

Bahrain

Hong Kong

Israel

Japan

Kuwait

Lebanon

Macau

Malaysia

Mexico

Oman

Qatar

Saudi Arabia

Singapore

South Korea

Taiwan

United Arab Emirates

Region B

Country

Algeria

Azerbaijan

Belarus

Egypt

Iran

Iraq

Jordan

Libya

Morocco

Philippines

Tunisia

Ukraine

Region C

Country

Afghanistan

Angola

Armenia

Bangladesh

Benin

Bhutan

Botswana

Burkina Faso

Burundi

Cambodia

Cameroon

Cape Verde

Central African Republic

Chad

Comoros

Congo

Congo, Dem. Rep. of the

Cote d'lvoire

Djibouti

Equatorial Guinea

Eritrea

Ethiopia

Fiji

Gabon

Gambia

Georgia

Ghana

Guinea

Guinea-Bissau

India

Indonesia

Kazakhstan

Kenya

Kiribati

Korea, Denim. People's Rep. of

Kyrgyzstan

Lao, People's Dem. Rep.

Lesotho

Liberia

Madagascar

Malawi

Maldives

Mali

Mauritania

Mauritius

Moldova, Rep. of

Mongolia

Mozambique

Myanmar

Namibia

Nauru

Nepal

Niger

Nigeria

Pakistan

Palau

Papua New Guinea

Rwanda

Samoa

Sao Tome and Principe

Senegal

Seychelles

Sierra Leone

Solomon Islands

Somalia

South Africa

South Sudan

Sri Lanka

Sudan

Swaziland

Syria

Tajikistan

Tanzania, U. Rep. of

Thailand

Timor-Leste

Togo

Tonga

Turkmenistan

Tuvalu

Uganda

Uzbekistan

Vanuatu

Vietnam

Yemen

Zambia

Zimbabwe

[*] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended

Annex Z: Territory Combination Product Supply to Tibotec

(this “Tibotec Distributor Agreement” or “TDA”)

Provision

Term

1 Defined Terms

Capitalized terms used and not defined in this TDA have the respective meanings assigned to them in the Collaboration Agreement. For clarity, this TDA shall be deemed part of the Collaboration Agreement. Unless otherwise indicated, all section cross-references in this TDA are to the Sections of this TDA and not the Collaboration Agreement. “Contract Manufacturer” or “CMO” shall mean any Third Party contract manufacturer with which (a) Gilead or its Affiliates contracts for the Manufacture of Territory Combination Product to fulfill its obligations hereunder, or (b) Tibotec or its Affiliates contracts for the labeling, packaging, handling or storage of Territory Combination Product. “Gilead Manufacturer” shall mean a Person that Manufactures Territory Combination Product supplied hereunder by or on behalf of Gilead and its Affiliates, whether it be Gilead, an Affiliate of Gilead or a Contract Manufacturer of Gilead (or an Affiliate of Gilead). “Supply Committee” shall have the meaning set forth in the TMC278 Supply Agreement. “Territory Combination Product Specifications” shall mean the specifications for Major Market Combination Product and Branded Region B/C Combination Product, as applicable, in each case as provided by Gilead to Tibotec promptly following NDA approval in the United States, as amended from time to time in accordance with this TDA. “Tibotec Packager” shall mean a Person that packages or labels Territory Combination Product supplied hereunder by or on behalf of Tibotec and its Affiliates, whether it be Tibotec, an Affiliate of Tibotec or a Contract Manufacturer of Tibotec (or an Affiliate of Tibotec).

2 Supply of Territory Combination Product; Minimum Shelf Life 2.1     Generally. Subject to the terms and conditions of the Collaboration Agreement, during the term of this TDA, Gilead shall sell to Tibotec, and Tibotec shall purchase exclusively from Gilead, pursuant to Firm Orders properly submitted to Gilead hereunder, all of Tibotec's requirements of Territory Combination Product in unlabeled bottles of Major Market Combination Product or Branded Region B/C Combination Product, as applicable, for use solely as permitted under the Collaboration Agreement. The Supply Committee shall determine the commencement date for Manufacture and sale to Tibotec under this TDA of Branded Region B/C Combination Product, including any required Manufacture of validation batches required by Applicable Law; provided that the Parties understand and agree that Gilead shall require [*] 2.1 Minimum Shelf Life. 2.2.1     [*] 2.2.2   [*] and for clarity Section 10.6(b) of the Collaboration Agreement shall apply.

3 Forecasts and Orders 3.1 Generally. On or before the first day of each month (the “Forecast Date”) during the term of this TDA, commencing as of the date specified in Section 3.2 or 3.3 of this TDA as applicable, Tibotec shall submit to Gilead, a forecast of the quantity of Major Market Combination Product and Branded Region B/C Combination Product that Tibotec expects to order [*] following the applicable Forecast Date (each, a “Forecast”). Each forecast shall be prepared in good faith consultation with Gilead. In addition, Tibotec shall, prior to the end of each Calendar Year during the Term, provide Gilead with Tibotec's good faith estimate of its annual requirements for Major Market Combination Product and Branded Region B/C Combination Product for [*] following the Calendar Year in which such estimate is given; provided, however, that, in the case of [*] 3.2 Major Market Combination Product. Commencing [*] before the anticipated Launch in the first (1st) Tibotec Country where Tibotec will be selling the Major Market Combination Product, Tibotec shall submit to Gilead a Forecast of the quantity of Major Market Combination Product that Tibotec expects to order for [*] following the applicable Forecast Date. The quantity of the Major Market Combination Product set forth in a given Forecast for [*] shall be binding. Except as provided in the foregoing sentence, Forecasts shall be considered non-binding. 3.3 Branded Region B/C Combination Product.  Commencing [*] before the anticipated Launch in the first Tibotec Country where Tibotec will be selling the Branded Region B/C Combination Product, Tibotec shall submit to Gilead a Forecast of the quantity of Branded Region B/C Combination Product that Tibotec expects to order for [*] following the applicable Forecast Date. Branded Region B/C Combination Product set forth in a given Forecast for [*] shall be binding. Except as provided in the foregoing sentence, Forecasts shall be considered non-binding. 3.4 Orders and Non-Binding Period. 3.4.1 Firm Orders. Tibotec shall notify Gilead, in the form of a purchase order or other form agreed by the Parties (each a “Firm Order”), of the Units of each of Major Market Combination Product and Branded Region B/C Combination Product to be Delivered to satisfy Tibotec's requirements at least [*] prior to the date on which such Territory Combination Product is to be Delivered. Each Firm Order shall (a) be consistent with the quantity set forth in the applicable binding portion of the Forecast; (b) be denominated in Units, unless otherwise mutually agreed by the Parties and (c) specify the Delivery date and any reasonable delivery instructions set forth in the Firm Order. Each Firm Order for Branded Region B/C Combination Product shall be [*]and, provided, further, that Tibotec acknowledges and agrees that production yield rates for Branded Region B/C Combination Product may inherently vary and that as a result Delivered lot sizes may inherently vary from the estimated lot size and the Parties' obligations as to such inherent variation are detailed in Section 6.1.2 of this TDA. 3.4.2 Non-Binding Forecasts [*] and by Supply Committee Determination. Notwithstanding Section 3.4.1, any Forecasts provided by Tibotec for [*] shall be deemed non-binding and the quantities of such Combination Product to be Delivered to Tibotec and timing of any such deliveries shall be determined by the Supply Committee and such determination of quantities and timing by the Supply Committee shall be binding on both Parties. 3.5 Russia. Tibotec shall place separate forecasts and Firm Orders for Major Market Combination Product that will be Distributed in Russia in accordance with Section 3.2 and 3.4. 3.6 Japan. Tibotec shall place separate forecasts and Firm Orders for Major Market Combination Product that will be Distributed in Japan in accordance with Section 3.2 and 3.4; provided, however, that such forecasts shall be [*] 3.7 Acceptance of Firm Orders. Within [*] of initial receipt of a Firm Order from Tibotec, Gilead shall notify Tibotec whether it accepts or rejects such Firm Order. Gilead shall accept any such Firm Order from Tibotec to the extent that such Firm Order complies with the requirements above. 3.8 Supply Committee. The roles and responsibilities of the Supply Committee shall include the supply of Major Market Combination Product and Branded Region B/C Combination Product, including issues related to supply for Japan and Russia and those responsibilities that are set forth in Section 2.2(c) of the TMC278 Supply Agreement but as applied to the Territory Combination Product rather than TMC278. 3.9 Distribution Limitation. Tibotec shall not Distribute (a) in Russia or Japan any Territory Combination Product ordered and Delivered for a country other than Russia or Japan, respectively, or (b) outside of Russia or Japan any Territory Combination Product ordered and Delivered for Russia or Japan, respectively.

4 Deviations from Firm Orders

4.1   [*] notify Tibotec of the quantities of Major Market Combination Product or Branded Region B/C Combination Product, as applicable, that Gilead expects to be able to Deliver by the delivery date specified in the applicable Firm Order. 4.2 Reduced Order Quantity. In the event that Tibotec places a Firm Order that is less than the binding Forecast for such period, [*]

5 Non-Conforming Product

5.1 Notice of Nonconformity. Tibotec shall notify Gilead in writing of any claim that any Territory Combination Product supplied under this TDA is not in conformance with the warranties set forth herein (“Nonconforming”) [*]  Tibotec shall promptly provide Gilead with a sample of such Nonconforming Territory Combination Product, if available, and all relevant reports, data, and laboratory test results indicating that such Territory Combination Product is Nonconforming. Tibotec shall [*]  If Gilead and Tibotec disagree as to whether Units of Territory Combination Product are Nonconforming, Gilead and Tibotec shall designate an independent testing laboratory reasonably acceptable to both Parties to make a determination, which determination shall be binding on the Parties, absent manifest error. Gilead shall [*] 5.2   [*] Nonconforming Territory Combination Product. If the independent testing laboratory (as set forth above) determines that the Territory Combination Product was Nonconforming or the Parties agree that the Territory Combination Product was Nonconforming, then [*] 5.3 Destruction of Nonconforming Territory Combination Product. Tibotec shall arrange for the destruction, return or other disposal, at Gilead's election, of any Nonconforming Territory Combination Product in compliance with Gilead's instructions and Applicable Law. [*]

6 Territory Combination Product Shortage; Failure to Supply	6.1 Inadequate Delivered Quantity of Territory Combination Product. 6.1.1 Tibotec shall notify Gilead in writing of any failure to Deliver Major Market Combination Product or a shortage in quantity in any shipment of Major Market Combination Product (as compared with the amount specified for Delivery in the applicable Firm Order given by Tibotec (as set forth above)) [*] days after Delivery (or scheduled Delivery) thereof. In the event Gilead disagrees with any claim of shortage by Tibotec, each Party shall designate a representative to be present at the inventorying of the at-issue Major Market Combination Product, the results of which shall be binding on the Parties, absent manifest error (and Gilead shall invoice Tibotec solely based on such binding inventory). Gilead shall use its Commercially Reasonable Efforts to promptly Deliver any shortage amount (as agreed upon by the Parties or determined by the inventory) of Major Market Combination Product as promptly as possible. [*] 6.1.2 For Firm Orders of Branded Region B/C Combination Product, Gilead's obligation to Deliver shall be deemed fulfilled if Gilead delivers [*] 6.2 Shortage of Territory Combination Product. If Gilead is unable to supply the full quantities of Territory Combination Product set forth in the Firm Orders from Tibotec and its Affiliates together with the amounts of Territory Combination Product needed by Gilead and its Affiliates, then Gilead shall allocate the available supply of Territory Combination Product [*] 6.3   Notification and Cure. If Gilead fails to supply Territory Combination Product for which it has received a Firm Order in accordance with this TDA, [*] then the matter shall be referred to the Executives for resolution pursuant to Section 2.4 of the Collaboration Agreement; provided that subsection 2.4(b) thereof shall not apply to such resolution. 6.4 Other Remedies. Subject to the express limitations set forth herein, the remedies set forth in this Section 6 for a material breach by Gilead shall be in addition to any other remedies Tibotec may have under this TDA, the Collaboration Agreement, or at law.
7 Territory Combination Product Packaging by Gilead	7.1   Labeling. Gilead shall supply Tibotec with Units of unlabeled bottles of Territory Combination Product. 7.2 Packaging. Each shipment shall be packed, sealed, and shipped in accordance with Gilead's customary packaging practices and GMP.
8 Packaging, Labeling and Storage Technology Transfer; Packaging and Labeling Requirements	8.1 Gilead shall assist Tibotec in establishing proper procedures with respect to packaging, labeling and storage of Territory Combination Product. 8.2 Gilead shall provide Tibotec with the core secondary packaging and packaging insert artwork with respect to the Territory Combination Product (“Core Materials” ) for use by Tibotec in packaging and labeling Territory Combination Product. Tibotec shall use the Core Materials to package and label the Territory Combination Product, but shall modify the Core Materials as required by Applicable Law and shall provide any necessary translations. Gilead shall have the right, but not the obligation, to review and approve in advance the Core Materials, as so modified, for any country for which Tibotec is the Selling Party.

9 Territory Combination Product Delivery

9.1 Delivery shall be [*] 9.2 The shipment shall be labeled with a traceable batch number. The bill of lading shall list the gross weight and net weight of the shipment. Concurrent with each shipment of Territory Combination Product, Gilead shall provide Tibotec with an electronic copy of the certificate of analysis confirming that such batch meets the applicable Specifications. In addition, upon delivery to Tibotec's carrier, Gilead shall provide Tibotec with notice that the shipment has been delivered, including the quantity of Territory Combination Product delivered. If Tibotec requests, Gilead shall provide a written certificate of compliance for a batch or batches of Territory Combination Product delivered to Tibotec.

10 Safety Stock

10.1 Safety Stocks. [*]

11 Quality Control 11.1 Warranty on Territory Combination Product. Gilead represents and warrants that, at the time of Delivery, the Territory Combination Product supplied hereunder, other than as a result of any defect or condition of the Supplied TMC278 included therein, including any breach of any warranty with respect to the Supplied TMC278 made by Tibotec in the TMC278 Supply Agreement (a) shall have been Manufactured in accordance with GMP and Applicable Law, and (b) shall conform to the Territory Combination Product Specifications for Major Market Combination Product or Branded Region B/C Combination Product, as applicable, and the applicable certificate of analysis. 11.2 Changes to Territory Combination Product Specifications.           11.2.1 Changes to Territory Combination Product Specifications that are an Additional Requirement, shall be governed by Section 8.4 of the Collaboration Agreement. All other changes to the Territory Combination Product Specifications for Major Market Combination Product or Branded Region B/C Combination Product shall be subject to the provisions in this TDA. 11.2.2 If Gilead wishes to amend the Territory Combination Product Specifications, Gilead shall provide written notice thereof to the Tibotec. [*]  Prior to delivery of Territory Combination Product to Tibotec pursuant to this TDA and solely to the extent not provided in the Product Specifications, Gilead shall establish and provide to Tibotec the specifications for bottle size and shape with respect to the supplied Territory Combination Product. Any changes to such bottle size and shape specifications shall be treated in accordance with the process for changing the Product Specifications. 11.3 Territory Combination Product Manufacturing-Related Changes. Manufacturing-related changes that are an Additional Requirement shall be governed by Section 8.4 of the Collaboration Agreement. Subject to the requirements above, other manufacturing-related changes with respect to Territory Combination Product, [*]  Any Manufacturing-Related Changes made with respect to Territory Combination Product shall, in each case, comply with GMP and Applicable Law. In the event of any such change, Gilead shall (i) be responsible to ensure that all Territory Combination Product Manufactured under the changed Manufacturing process by or on behalf of Gilead or its Affiliates meets the applicable Territory Combination Product Specifications, and (ii) provide Tibotec in a timely manner with all information reasonably needed to make corresponding amendments to the applicable regulatory filings in the Territory maintained by Tibotec with respect to the Territory Combination Product (including amending Approvals in the Territory), to the extent necessary. 11.4 Quality Agreements. 11.4.1 Between Gilead and its CMOs. During the term of this TDA, Gilead shall have quality agreements in place with each of its Contract Manufacturers that Manufacture Territory Combination Product for supply hereunder. Such quality agreements shall, at a minimum, have terms governing GMP compliance as are customary in the pharmaceutical industry. 11.4.2 Between Gilead and Tibotec. Prior to the shipment of any Territory Combination Product hereunder, the Parties shall enter into an agreement which sets out the policies, procedures, and standards by which the Parties shall coordinate and implement the operational and quality assurance activities and regulatory compliance objectives contemplated under this TDA with respect to the Territory Combination Product and the subsequent labeling, packaging and storage of such Territory Combination Product by Tibotec (the “Quality Agreement”). Any amendment to the Quality Agreement shall require the written agreement of the Parties. 11.4.3 Between Tibotec and its CMOs. During the term of this TDA, Tibotec shall have quality agreements in place with each of its CMOs that package, label or handle Territory Combination Product purchased hereunder. Such quality agreements shall, at a minimum, have terms governing GMP compliance as are customary in the pharmaceutical industry.

12 Combination Product Inspections 12.1 [*] Inspections. During the term of this TDA and no more than [*]  (a) Tibotec and/or its agents may inspect, during regular business hours, [*] to ascertain compliance with GMP, Applicable Law, the Territory Combination Product Specifications and the terms of this TDA in the Manufacture, handling and shipping of Territory Combination Product; and (b) Gilead and/or its agents may inspect, during regular business hours, [*] to ascertain compliance with GMP, Applicable Law, the Territory Combination Product Specifications and the terms of this TDA. Any such inspection of a Contract Manufacturer, a Gilead Manufacturer or a Tibotec Packager shall be coordinated with inspections thereof conducted by or on behalf of the other Party or its Affiliates, and may be conditioned on the execution of a customary confidentiality agreement between the inspecting Party (or its agent) and such Contract Manufacturer, Gilead Manufacturer or Tibotec Packager. As part of any inspection conducted pursuant to this Section, the inspecting Party and/or its agents may inspect, as applicable, [*] (such activities, an “Inspection”). 12.2 “For Cause” Inspection. 12.2.1 Tibotec may conduct an Inspection of the relevant facilities of any Gilead Manufacturer that supplies Territory Combination Product hereunder, if such an Inspection is a reasonable response to a Regulatory Authority audit notice or inquiry regarding any Territory Combination Product, an unresolved deviation in the Manufacture of the Territory Combination Product, or customer complaints or adverse events regarding the Territory Combination Product. Tibotec and Gilead shall coordinate in good faith as to the timing of any Inspection of a Contract Manufacturer conducted pursuant to this Section and Gilead or its designee shall be present at any such Inspection. 12.2.2 Gilead may conduct an Inspection of the relevant facilities of any Tibotec Packager, if such an Inspection is a reasonable response to a Regulatory Authority audit notice or inquiry regarding any Territory Combination Product, an unresolved deviation in the packaging, labeling or storage of the Territory Combination Product, or customer complaints or adverse events regarding the Territory Combination Product. Tibotec and Gilead shall coordinate in good faith as to the timing of any Inspection of a Contract Manufacturer conducted pursuant to this Section and Tibotec or its designee shall be present at any such Inspection. 12.3 Remedial Efforts. Following any Inspection conducted (as described above), the Parties shall meet to discuss the inspecting Party's findings, and [*]

13 Payments 13.1 Territory Combination Product. Subject to the terms and conditions of this TDA and the Collaboration Agreement, for Territory Combination Product Delivered by Gilead to Tibotec hereunder, Gilead shall issue to Tibotec an invoice upon shipment of the Territory Combination Product as provided in Annex BB of the Collaboration Agreement. Each such invoice shall state the quantity of Major Market Combination Product and Branded Region B/C Combination Product covered by such invoice and specify all amounts due in United States Dollars. Subject to the terms and conditions of this TDA and the Collaboration Agreement, Tibotec shall pay each such invoice in accordance with the payment terms set forth in Annex BB of the Collaboration Agreement. 13.2 Expenses. Any expenses and/or losses hereunder which are deemed in this TDA to be included in the Manufacturing Fee shall be calculated and invoiced in accordance with Section 10.2 of the Collaboration Agreement. Unless otherwise agreed by the Parties (including in the preceding sentence and in Section 10 of the Collaboration Agreement), (a) each Party promptly shall invoice the other Party for any amounts due under this TDA and (b) each Party shall pay any valid invoice provided by the other Party pursuant to this TDA within [*] after receipt of such invoice.

14 Tibotec Representations, Warranties and Covenants 14.1 Warranty on Distributed Territory Combination Product. Tibotec represents and warrants that, at the time of distribution or sale of Territory Combination Product supplied hereunder to Third Parties, that such Territory Combination Product shall not be expired or otherwise unfit for sale as a result of Tibotec's packaging, labeling, handling or storage of such Territory Combination Product and such Territory Combination Product shall be in conformance with the Territory Combination Product Specifications and Applicable Law with respect to packaging and labeling. 14.2 Permits. Tibotec shall obtain and maintain, all necessary permits for the packaging, labeling, receipt, storage, handling and distribution of Territory Combination Product at the facility(ies) where Territory Combination Product supplied hereunder is packaged, labeled and/or stored by or on behalf of Tibotec or its Affiliates. 14.3 Manufacturing and Storage Records. Tibotec shall maintain complete and accurate records relating to the receipt, handling, storage, use, packaging, labeling and disposal by or on behalf of Tibotec or its Affiliates of the Territory Combination Product supplied hereunder and standard operating procedures for the foregoing in accordance with Applicable Law and GMP and shall provide a written account of any discrepancies. Gilead shall have the right to review such records upon the reasonable request of Gilead. 14.4 Packaging and Labeling Specifications. Tibotec shall label and package the Territory Combination Product in accordance with GMP and Applicable Law for the country or region in which such Territory Combination Product will be sold, released or distributed. If any Territory Combination Product intended for release, sale or distribution by Tibotec fails to comply with the labeling and packaging requirements in accordance with the Territory Combination Product Specifications or Applicable Law for the country or region in which such Territory Combination Product will be sold, released or distributed, then Tibotec shall not release, sell or distribute such Territory Combination Product. 14.5 Tibotec Packagers. Tibotec shall, or shall cause the Tibotec Packagers to, maintain the facilities, equipment and machinery used in connection with the labeling and packaging of Territory Combination Product in a state of repair and operating efficiency that enables it to meet the applicable Territory Combination Product Specifications. Tibotec shall, or shall cause such Tibotec Packagers to, validate the equipment and the labeling and packaging process and any other appropriate steps performed at such facilities and validate/calibrate all instruments used in testing such equipment and machinery, in each case to the extent used in connection with the labeling or packaging of Territory Combination Product and as required by GMP and Applicable Law. 14.6 Handling and Storage. Tibotec shall at all times handle, store and transport Territory Combination Product in accordance with Applicable Law, GMP and GDP and in a manner and with a level of care consistent with Tibotec's handling, storage and transport of similar pharmaceutical products.

15 Consequences of Termination	15.1 Consequences of Termination. In the event the Collaboration Agreement terminates or upon Tibotec ceasing to Distribute Territory Collaboration Product and/or there ceasing to be any Tibotec Countries, the following provisions shall apply: 15.1.1 Prior Orders. [*] 15.1.2 Territory Combination Product. Upon termination of the Collaboration Agreement by Tibotec for a Material Breach by Gilead, [*]
16 Survival	The following provisions of this TDA shall survive the expiry or termination of the Collaboration Agreement (which expiration or termination shall automatically terminate this TDA): Sections 1, 3.9, 9 (with respect to any Territory Combination Product Delivered following termination of this TDA), 11.1, 11.4.3, 14.3 (to the extent such records are required for a period of three (3) years following termination), 15, 16, 17 and 18. In addition to any other Sections which may survive pursuant to this Section 16, the provisions of Sections 2.2, 3.8, 5 (provided that there shall be no obligation to replace Nonconforming Territory Combination Product), 6 (provided that there shall be no obligation to [*]), 8.2 (solely with respect to Tibotec's packaging and labeling obligations), 13 and 14 shall survive, in each case solely with regard to the Territory Combination Product Delivered by Gilead.
17 Subcontracting	Subject to the terms and conditions of this TDA, Gilead may subcontract the Manufacture of Territory Combination Product to one or more Contract Manufacturers. Gilead shall have the right to select such Contract Manufacturers in its sole discretion. In the event that Gilead delegates any of its obligations under this TDA to a subcontractor, Gilead shall remain primarily (and not secondarily or derivatively) liable for the full and timely performance by such subcontractor of all its obligations under this TDA. Notwithstanding anything to the contrary contained herein, if Gilead engages a subcontractor to fulfill any of Gilead's obligations hereunder, Gilead shall cause such subcontractor to comply with the provisions of this TDA.
18 Incorporation with Collaboration Agreement; Interpretation	This TDA is incorporated into and subject to the terms of the Collaboration Agreement. If there is any inconsistency between the provisions of this TDA and the provisions of the Collaboration Agreement, the provisions of the Collaboration Agreement shall control. If there is any inconsistency between the provisions of this TDA and the Quality Agreement, or any purchase order, confirmation, or other document passing between the Parties relating to supply of Territory Combination Product by Gilead to Tibotec or the subsequent packaging, handling or storage of the Territory Combination Product by Tibotec hereunder, the provisions of this TDA shall control except that the Quality Agreement controls with respect to procedures for verifying compliance with quality requirements.

EX-31.1

Exhibit 31.1

CERTIFICATION

I, John C. Martin, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Gilead Sciences, Inc.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: May 8, 2013

/s/    JOHN C. MARTIN        

John C. Martin, Ph.D.

Chairman and Chief Executive Officer

EX-31.2

Exhibit 31.2

CERTIFICATION

I, Robin L. Washington, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Gilead Sciences, Inc.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: May 8, 2013

/S/    ROBIN L. WASHINGTON      

Robin L. Washington

Senior Vice President and Chief Financial Officer

EX-32.1

Exhibit 32.1

CERTIFICATIONS

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (18 U.S.C. § 1350, as adopted), John C. Martin, Ph.D., the Chairman and Chief Executive Officer of Gilead Sciences, Inc. (the Company), and Robin L. Washington, the Senior Vice President and Chief Financial Officer of the Company, each hereby certifies that, to the best of his or her knowledge:

1. The Company’s Quarterly Report on Form 10-Q for the period ended March 31, 2013, to which this Certification is attached as Exhibit 32 (the Periodic Report), fully complies with the requirements of Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934, as amended; and

2. The information contained in the Periodic Report fairly presents, in all material respects, the financial condition of the Company at the end of the periods covered by the Periodic Report and results of operations of the Company for the periods covered by the Periodic Report.

Dated: May 8, 2013

/s/    JOHN C. MARTIN	/s/    ROBIN L. WASHINGTON
John C. Martin, Ph.D. Chairman and Chief Executive Officer	Robin L. Washington Senior Vice President and Chief Financial Officer

This certification accompanies the Form 10-Q to which it relates, is not deemed filed with the SEC and is not to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing.

XML

Available-for-Sale Securities Summary of Available-for-Sale Securities at Estimated Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Schedule of Available-for-Sale Securities [Line Items]
Estimated Fair Value	$ 2,400,211	$ 2,194,748
US Treasury Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	95,661	81,752
Gross Unrealized Gains	194	151
Gross Unrealized Losses	0	0
Estimated Fair Value	95,855	81,903
Money Market Funds [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	1,633,153	1,416,356
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	1,633,153	1,416,356
US Government Agencies Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	217,680	248,595
Gross Unrealized Gains	358	386
Gross Unrealized Losses	0	(29)
Estimated Fair Value	218,038	248,952
Municipal Debt Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	12,049	12,062
Gross Unrealized Gains	66	33
Gross Unrealized Losses	0	(7)
Estimated Fair Value	12,115	12,088
Corporate Debt Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	353,468	351,309
Gross Unrealized Gains	1,630	1,492
Gross Unrealized Losses	(35)	(84)
Estimated Fair Value	355,063	352,717
Residential Mortgage and Asset-Backed Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	86,034	82,717
Gross Unrealized Gains	96	156
Gross Unrealized Losses	(143)	(141)
Estimated Fair Value	85,987	82,732
Total [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	2,398,045	2,192,791
Gross Unrealized Gains	2,344	2,218
Gross Unrealized Losses	(178)	(261)
Estimated Fair Value	$ 2,400,211	$ 2,194,748

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Intangible Assets and Goodwill Schedule of Finite Lived Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Ranexa [Member]
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	$ 147,552	$ 133,119
Finite-Lived Intangible Assets, Gross Carrying Amount	688,400	688,400
Lexiscan [Member]
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	101,902	95,466
Finite-Lived Intangible Assets, Gross Carrying Amount	262,800	262,800
Other [Member]
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	16,093	15,417
Finite-Lived Intangible Assets, Gross Carrying Amount	42,995	42,995
Total Member
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	265,547	244,002
Finite-Lived Intangible Assets, Gross Carrying Amount	$ 994,195	$ 994,195

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Derivative Financial Instruments Derivative financial instruments Narrative (Details) (USD $) In Billions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional Amount of Foreign Currency Derivatives	$ 3.47	$ 3.39

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Intangible Assets and Goodwill Schedule of Future Amortization Expense (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
2013 (remaining nine months)	$ 64,636
2014	92,441
2015	97,673
2016	107,312
2017	116,137
2018	124,561
Total	$ 602,760

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Derivative Financial Instruments Summary of the effect of foreign currency exchange contracts on consolidated statements of income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Net Gains (Losses) Recognized in OCI (effective portion)	$ 70,860	$ (48,886)
Net Gains Reclassified from Accumulated OCI into Product Sales (effective portion)	462	11,227
Losses Recognized in Other Income (Expense), Net (ineffective portion and amounts excluded from effectiveness testing)	(2,132)	(3,212)
Net Gains (Losses) Recognized in Other Income (Expense), Net	$ 32,620	$ (27,174)

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Summary of Significant Accounting Policies Reconciliation Of The Numerator And Denominator Used In The Calculation Of Basic And Diluted Net Income Per Share (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Sep. 30, 2011
Numerator And Denominator Used In The Calculation Of Basic And Diluted Net Income Per Share [Line Items]
Net Income Attributable to Gilead	$ 722,186	$ 441,956	$ 441,956
Weighted-average shares of common stock outstanding used in the calculation of basic net income per share attributable to Gilead common stockholders (shares)	1,521,372	1,512,572	1,512,572
Stock Options and Equivalents (shares)	36,812		29,746
Warrants Related to the Convertible Notes (shares)	45,479		0
Weighted-average shares of common stock outstanding used in the calculation of diluted net income per share attributable to Gilead common stockholders (shares)	1,665,060	1,554,776	1,554,776
Convertible Senior Notes Due In May 2013 [Member]
Numerator And Denominator Used In The Calculation Of Basic And Diluted Net Income Per Share [Line Items]
Conversion Spread (shares)	10,703		6,846
Convertible Senior Notes Due In May 2014 [Member]
Numerator And Denominator Used In The Calculation Of Basic And Diluted Net Income Per Share [Line Items]
Conversion Spread (shares)	25,554		3,010
Convertible Senior Notes Due In May 2016 [Member]
Numerator And Denominator Used In The Calculation Of Basic And Diluted Net Income Per Share [Line Items]
Conversion Spread (shares)	25,140		2,602

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Intangible Assets and Goodwill Intangible Assets and Goodwill (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Feb. 08, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Fair Value of Acquired Assets and Assumed Liabilities			$ 487.6
Acquired Indefinite-Lived Intangible Asset			362.7
Amortization of Intangible Assets	21.5	15.8
Finite-Lived Intangible Asset, Useful Life	11 years
Goodwill Resulting from the Acquisition of YM			$ 127.2

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Available-for-Sale Securities Available-for-sale securities (Tables)

3 Months Ended

Mar. 31, 2013

Investments, Debt and Equity Securities [Abstract]

Summary of Available-for-Sale Securities at Estimated Fair Value [Table Text Block]

The following table is a summary of available-for-sale debt securities recorded in cash and cash equivalents or marketable securities in our Consolidated Balance Sheets (in thousands):

	March 31, 2013									December 31, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Debt securities:
U.S. treasury securities	$	95,661	$	194	$	—		$	95,855	$	81,752	$	151	$	—		$	81,903
Money market funds	1,633,153		—		—			1,633,153		1,416,356		—		—			1,416,356
U.S. government agencies securities	217,680		358		—			218,038		248,595		386		(29		)	248,952
Municipal debt securities	12,049		66		—			12,115		12,062		33		(7		)	12,088
Corporate debt securities	353,468		1,630		(35		)	355,063		351,309		1,492		(84		)	352,717
Residential mortgage and asset-backed securities	86,034		96		(143		)	85,987		82,717		156		(141		)	82,732
Total	$	2,398,045	$	2,344	$	(178	)	$	2,400,211	$	2,192,791	$	2,218	$	(261	)	$	2,194,748

Summary of the Classification of Available-for-Sale Securities [Table Text Block]

The following table summarizes the classification of the available-for-sale debt securities on our Consolidated Balance Sheets (in thousands):

	March 31, 2013		December 31, 2012
Cash and cash equivalents	$	1,633,153	$	1,416,356
Short-term marketable securities	78,804		58,556
Long-term marketable securities	688,254		719,836
Total	$	2,400,211	$	2,194,748

Summary of Available-for-Sale Securities by Contractual Maturity [Table Text Block]

The following table summarizes our portfolio of available-for-sale debt securities by contractual maturity (in thousands):

	March 31, 2013
	Amortized Cost		Fair Value
Less than one year	$	1,711,889	$	1,711,957
Greater than one year but less than five years	661,969		664,058
Greater than five years but less than ten years	9,437		9,460
Greater than ten years	14,750		14,736
Total	$	2,398,045	$	2,400,211

Summary of Gross Realized Gains (Losses) Related to Sales of Marketable Securities [Table Text Block]

The following table summarizes the gross realized gains and losses related to sales of marketable securities (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Gross realized gains on sales	$	182		$	10,015
Gross realized losses on sales	$	(156	)	$	(40,096	)

Summary of Available-for-Sale Securities in a Continuous Loss Position Deemed not to be Other-than-Temporarily Impaired [Table Text Block]

The following table summarizes our available-for-sale debt securities that were in a continuous unrealized loss position, but were not deemed to be other-than-temporarily impaired (in thousands):

	Less Than 12 Months					12 Months or Greater				Total
	Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value
March 31, 2013
Debt securities:
U.S. government agencies securities	$	—		$	—	$	—	$	—	$	—		$	—
Municipal debt securities	—			—		—		—		—			—
Corporate debt securities	(35		)	47,567		—		—		(35		)	47,567
Residential mortgage and asset-backed securities	(143		)	47,748		—		—		(143		)	47,748
Total	$	(178	)	$	95,315	$	—	$	—	$	(178	)	$	95,315
December 31, 2012
Debt securities:
U.S. government agencies securities	$	(29	)	$	26,306	$	—	$	—	$	(29	)	$	26,306
Municipal debt securities	(7		)	3,993		—		—		(7		)	3,993
Corporate debt securities	(84		)	72,722		—		—		(84		)	72,722
Residential mortgage and asset-backed securities	(141		)	36,415		—		—		(141		)	36,415
Total	$	(261	)	$	139,436	$	—	$	—	$	(261	)	$	139,436

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Inventories Schedule of inventories (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Inventory Disclosure [Abstract]
Raw Materials	$ 693,139	$ 826,545
Work in Process	529,157	358,525
Finished Goods	577,322	559,912
Total	$ 1,799,618	$ 1,744,982

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Available-for-Sale Securities Summary of Gross Realized Gains and Losses Related to Sales of Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Investments, Debt and Equity Securities [Abstract]
Gross Realized Gains on Sales	$ 182	$ 10,015
Gross Realized Losses on Sales	$ (156)	$ (40,096)

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Fair value measurements Contingent Consideration Rollforward (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, December 31, 2012	$ 205,060
Additions from new acquisitions	0
Net changes in valuation	6,024
Balance, March 31, 2013	$ 211,084

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Intangible Assets and Goodwill Schedule of Carrying Amount of Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Goodwill and Intangible Assets Disclosure [Abstract]
Indefinite-Lived Intangible Assets	$ 11,348,900	$ 10,986,200
Finite-Lived Intangible Assets	728,648	750,193
Total Intangible Assets	$ 12,077,548	$ 11,736,393

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Segment information Segment information narrative (Details)	3 Months Ended
	Mar. 31, 2013
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Major Customers Percentage Of Total Revenues Minimum	10.00%

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Stock-Based Compensation Summary of Stock-Based Compensation (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-Based Compensation Expense Included in Total Costs and Expenses	$ 61,767	$ 242,668
Income Tax Effect	(16,387)	(13,064)
Stock-Based Compensation Expense, Net of Tax	45,380	229,604
Cost of Goods Sold [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-Based Compensation Expense Included in Total Costs and Expenses	1,841	2,101
Research and Development Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-Based Compensation Expense Included in Total Costs and Expenses	26,875	118,622
Selling, General and Administrative Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-Based Compensation Expense Included in Total Costs and Expenses	$ 33,051	$ 121,945

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Derivative Financial Instruments Table of Offsetting Derivative Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Derivative Assets [Abstract]
Derivatives - Gross Amounts of Recognized Assets	$ 43,182	$ 14,823
Derivatives - Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Derivatives - Amount of Assets Presented in the Consolidated Balance Sheet	43,182	14,823
Derivatives - Gross Amounts Not Offset in the Concolidated Balance Sheet - Derivative Financial Instruments	(18,515)	(9,644)
Derivatives - Gross Amounts Not Offset in the Consolidated Balance Sheet - Cash Collateral Received/Pledged	0	0
Derivatives - Net Amount (Legal Offset)	24,667	5,179
Derivative Liabilities [Abstract]
Derivatives - Gross Amount of Recognized Liabilities	(18,671)	(65,248)
Derivatives - Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Derivatives - Amounts of Liabilities Presented in the Consolidated Balance Sheet	(18,671)	(65,248)
Derivatives - Gross Amount Not Offset in the Consolidated Balance Sheet - Derivative Financial Instruments	18,515	9,644
Derivatives - Gross Amount Not Offset in the Consolidated Balance Sheet - Cash Collateral Received/Pledged	0	0
Derivatives - Net Amount (Legal Offset)	$ (156)	$ (55,604)

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Fair value measurements

3 Months Ended

Mar. 31, 2013

Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]

Fair Value Disclosures [Text Block]

FAIR VALUE MEASUREMENTS

We determine the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:

• Level 1 inputs which include quoted prices in active markets for identical assets or liabilities;

• Level 2 inputs which include observable inputs other than Level 1 inputs, such as quoted prices for similar assets or liabilities; quoted prices for identical or similar assets or liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability. For our marketable securities, we review trading activity and pricing as of the measurement date. When sufficient quoted pricing for identical securities is not available, we use market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data; and

• Level 3 inputs which include unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the underlying asset or liability. Level 3 assets and liabilities include those whose fair value measurements are determined using pricing models, discounted cash flow methodologies or similar valuation techniques and significant management judgment or estimation.

Our financial instruments consist principally of cash and cash equivalents, marketable securities, accounts receivable, foreign currency exchange forward and option contracts, accounts payable and short-term and long-term debt. Cash and cash equivalents, marketable securities and foreign currency exchange contracts that hedge accounts receivable and forecasted sales are reported at their respective fair values on our Consolidated Balance Sheets. Short-term and long-term debt are reported at their amortized cost on our Consolidated Balance Sheets. The remaining financial instruments are reported on our Consolidated Balances Sheets at amounts that approximate current fair values.

The fair values of our Convertible Notes and senior unsecured notes were determined using Level 2 inputs based on their quoted market values. The following table summarizes the carrying values and fair values of the Convertible Notes and senior unsecured notes (in thousands):

		March 31, 2013				December 31, 2012
Type of Borrowing	Description	Carrying Value		Fair Value		Carrying Value		Fair Value
Convertible Senior	May 2013 Notes	$	342,759	$	825,330	$	419,433	$	815,297
Convertible Senior	May 2014 Notes	1,211,072		2,696,870		1,210,213		2,040,363
Convertible Senior	May 2016 Notes	1,156,632		2,704,726		1,157,692		2,110,938
Senior Unsecured	April 2021 Notes	993,138		1,133,650		992,923		1,146,990
Senior Unsecured	December 2014 Notes	749,473		771,398		749,394		772,650
Senior Unsecured	December 2016 Notes	699,152		749,784		699,095		748,902
Senior Unsecured	December 2021 Notes	1,247,501		1,405,125		1,247,428		1,420,725
Senior Unsecured	December 2041 Notes	997,828		1,208,000		997,810		1,252,090

The following table summarizes, for assets or liabilities recorded at fair value, the respective fair value and the classification by level of input within the fair value hierarchy defined above (in thousands):

	March 31, 2013								December 31, 2012
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Assets:
Debt securities:
U.S. treasury securities	$	95,855	$	—	$	—	$	95,855	$	81,903	$	—	$	—	$	81,903
Money market funds	1,633,153		—		—		1,633,153		1,416,355		—		—		1,416,355
U.S. government agencies securities	—		218,038		—		218,038		—		248,952		—		248,952
Municipal debt securities	—		12,115		—		12,115		—		12,088		—		12,088
Corporate debt securities	—		355,063		—		355,063		—		352,718		—		352,718
Residential mortgage and asset-backed securities	—		85,987		—		85,987		—		82,732		—		82,732
Total debt securities	1,729,008		671,203		—		2,400,211		1,498,258		696,490		—		2,194,748
Derivatives	—		43,182		—		43,182		—		14,823		—		14,823
	$	1,729,008	$	714,385	$	—	$	2,443,393	$	1,498,258	$	711,313	$	—	$	2,209,571
Liabilities:
Contingent consideration	$	—	$	—	$	211,084	$	211,084	$	—	$	—	$	205,060	$	205,060
Derivatives	—		18,671		—		18,671		—		65,248		—		65,248
	$	—	$	18,671	$	211,084	$	229,755	$	—	$	65,248	$	205,060	$	270,308

Level 2 Inputs

We estimate the fair values of our government related debt, corporate debt, residential mortgage and asset-backed securities by taking into consideration valuations obtained from third-party pricing services. The pricing services utilize industry standard valuation models, including both income- and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities; issuer credit spreads; benchmark securities; prepayment/default projections based on historical data; and other observable inputs.

Substantially all of our foreign currency derivatives contracts have maturities primarily over an 18 month time horizon and all are with counterparties that have a minimum credit rating of A- or equivalent by Standard & Poor's, Moody's Investors Service, Inc. or Fitch, Inc. We estimate the fair values of these contracts by taking into consideration valuations obtained from a third-party valuation service that utilizes an income-based industry standard valuation model for which all significant inputs are observable, either directly or indirectly. These inputs include foreign currency rates, London Interbank Offered Rates (LIBOR) and swap rates. These inputs, where applicable, are at commonly quoted intervals.

Level 3 Inputs

For the three months ended March 31, 2013, we held no assets measured using Level 3 inputs. For the three months ended March 31, 2012, assets measured at fair value using Level 3 inputs were comprised of auction rate securities and Greek bonds within our available-for-sale investment portfolio. Our policy is to recognize transfers into or out of Level 3 classification as of the actual date of the event or change in circumstances that caused the transfer.

Auction Rate Securities

As of March 31, 2013, we did not hold any auction rate securities. During the third quarter of 2012, we sold our remaining portfolio of auction rate securities and as a result of the sale, we received total proceeds of $37.3 million which resulted in a $3.8 million loss that was recognized in other income (expense), net on our Consolidated Statement of Income.

The underlying assets of our auction rate securities consisted of student loans. Although auction rate securities would typically be measured using Level 2 inputs, the failure of auctions and the lack of market activity and liquidity experienced since the beginning of 2008 required that these securities be measured using Level 3 inputs. The fair value of our auction rate securities was determined using a discounted cash flow model that considered projected cash flows for the issuing trusts, underlying collateral and expected yields. Projected cash flows were estimated based on the underlying loan principal, bonds outstanding and payout formulas. The weighted-average life over which the cash flows were projected considered the collateral composition of the securities and related historical and projected prepayments.

Greek Government Bonds

As of March 31, 2013, we did not hold any Greek government bonds. During the first quarter of 2012, the Greek government restructured its sovereign debt which impacted all holders of Greek bonds. As a result, we recorded a $40.1 million loss related to the debt restructuring as part of other income (expense), net on our Consolidated Statement of Income and exchanged the Greek government-issued bonds for new securities, which we liquidated during the first quarter of 2012. We estimated the fair value of the Greek zero-coupon bonds using Level 3 inputs due to the then current lack of market activity and liquidity. The discount rates used in our fair value model for these bonds were based on credit default swap rates.

Contingent Consideration Liabilities

In connection with certain acquisitions, we may be required to pay future consideration that is contingent upon the achievement of specified development, regulatory approval or sales-based milestone events. We estimate the fair value of the contingent consideration liabilities on the acquisition date and each reporting period thereafter using a probability-weighted income approach, which reflects the probability and timing of future payments. This fair value measurement is based on significant Level 3 inputs such as the anticipated timelines and probability of achieving development, regulatory approval or sales-based milestone events and projected revenues. The resulting probability-weighted cash flows are discounted using credit-risk adjusted interest rates.

Each reporting period thereafter, we revalue these obligations by performing a review of the assumptions listed above and record increases or decreases in the fair value of these contingent consideration obligations in research and development (R&D) expenses within our Consolidated Statements of Income until such time that the related product candidate receives marketing approval. In the absence of any significant changes in key assumptions, the quarterly determination of fair values of these contingent consideration obligations would primarily reflect the passage of time.

Significant judgment is employed in determining Level 3 inputs and fair value measurements as of the acquisition date and for each subsequent period. Updates to assumptions could have a significant impact on our results of operations in any given period and actual results may differ from estimates. For example, significant increases in the probability of achieving a milestone or projected revenues would result in a significantly higher fair value measurement while significant decreases in the estimated probability of achieving a milestone or projected revenues would result in a significantly lower fair value measurement. Significant increases in the discount rate or in the anticipated timelines would result in a significantly lower fair value measurement while significant decreases in the discount rate or anticipated timelines would result in a significantly higher fair value measurement.

The potential contingent consideration payments required upon achievement of development or regulatory approval-based milestones related to our CGI Pharmaceuticals, Inc. and Calistoga Pharmaceuticals, Inc. acquisitions range from no payment if none of the milestones are achieved to an estimated maximum of $254.0 million (undiscounted), of which we had accrued $163.9 million as of March 31, 2013 and $159.3 million as of December 31, 2012. The remainder of the contingent consideration liabilities accrual as of March 31, 2013 and December 31, 2012 relates to potential future payments resulting from the acquisition of Arresto Biosciences, Inc. for royalty obligations on future sales once specified sales-based milestones are achieved.

The following table provides a rollforward of our contingent consideration liabilities, which are recorded as part of other long-term obligations in our Consolidated Balance Sheets (in thousands):

Balance at December 31, 2012	$	205,060
Additions from new acquisitions	—
Net changes in valuation	6,024
Balance at March 31, 2013	$	211,084

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Stock-Based Compensation Stock-Based Compensation (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated Stock-Based Compensation Expense	$ 100.1
Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated Stock-Based Compensation Expense	$ 93.8

XML

Available-for-Sale Securities Summary of Available-for-Sale Securities in a Continuous Unrealized Loss Position Deemed not to be Other-than-Temporarily Impaired (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Schedule of Available-for-Sale Securities [Line Items]
Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	$ (178)	$ (261)
Continuous Unrealized Loss Position, Less than 12 Months, Estimated Fair Value	95,315	139,436
Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses	0	0
Continuous Unrealized Loss Position, 12 Months or Greater, Estimated Fair Value	0	0
Continuous Unrealized Loss Position, Gross Unrealized Losses	(178)	(261)
Continuous Unrealized Loss Position, Estimated Fair Value	95,315	139,436
US Government Agencies Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	0	(29)
Continuous Unrealized Loss Position, Less than 12 Months, Estimated Fair Value	0	26,306
Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses	0	0
Continuous Unrealized Loss Position, 12 Months or Greater, Estimated Fair Value	0	0
Continuous Unrealized Loss Position, Gross Unrealized Losses	0	(29)
Continuous Unrealized Loss Position, Estimated Fair Value	0	26,306
Municipal Debt Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	0	(7)
Continuous Unrealized Loss Position, Less than 12 Months, Estimated Fair Value	0	3,993
Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses	0	0
Continuous Unrealized Loss Position, 12 Months or Greater, Estimated Fair Value	0	0
Continuous Unrealized Loss Position, Gross Unrealized Losses	0	(7)
Continuous Unrealized Loss Position, Estimated Fair Value	0	3,993
Corporate Debt Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(35)	(84)
Continuous Unrealized Loss Position, Less than 12 Months, Estimated Fair Value	47,567	72,722
Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses	0	0
Continuous Unrealized Loss Position, 12 Months or Greater, Estimated Fair Value	0	0
Continuous Unrealized Loss Position, Gross Unrealized Losses	(35)	(84)
Continuous Unrealized Loss Position, Estimated Fair Value	47,567	72,722
Residential Mortgage and Asset-Backed Securities [Member]
Schedule of Available-for-Sale Securities [Line Items]
Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(143)	(141)
Continuous Unrealized Loss Position, Less than 12 Months, Estimated Fair Value	47,748	36,415
Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses	0	0
Continuous Unrealized Loss Position, 12 Months or Greater, Estimated Fair Value	0	0
Continuous Unrealized Loss Position, Gross Unrealized Losses	(143)	(141)
Continuous Unrealized Loss Position, Estimated Fair Value	$ 47,748	$ 36,415

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Long-Term Obligations Long-Term Obligations (Tables)

3 Months Ended

Mar. 31, 2013

Long-term Debt, Unclassified [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

The following table summarizes the carrying amount of our borrowings under various financing arrangements (in thousands):

Type of Borrowing	Description	Issue Date	Due Date	Interest Rate	March 31, 2013		December 31, 2012
Convertible Senior	May 2013 Notes	April 2006	May 2013	0.625%	$	342,759	$	419,433
Convertible Senior	May 2014 Notes	July 2010	May 2014	1.00%	1,211,072		1,210,213
Convertible Senior	May 2016 Notes	July 2010	May 2016	1.625%	1,156,632		1,157,692
Senior Unsecured	April 2021 Notes	March 2011	April 2021	4.50%	993,138		992,923
Senior Unsecured	December 2014 Notes	December 2011	December 2014	2.40%	749,473		749,394
Senior Unsecured	December 2016 Notes	December 2011	December 2016	3.05%	699,152		699,095
Senior Unsecured	December 2021 Notes	December 2011	December 2021	4.40%	1,247,501		1,247,428
Senior Unsecured	December 2041 Notes	December 2011	December 2041	5.65%	997,828		997,810
Credit Facility	Five-Year Revolver	January 2012	January 2017	Variable	600,000		750,000
Total debt, net					$	7,997,555	$	8,223,988
Less current portion					942,759		1,169,433
Total long-term debt, net					$	7,054,796	$	7,054,555

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Intangible Assets and Goodwill Intangible Assets and Goodwill (Tables)

3 Months Ended

Mar. 31, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite Lived and Indefinite Lived Intangible Assets [Table Text Block]

The following table summarizes the carrying amount of our intangible assets (in thousands):

	March 31, 2013		December 31, 2012
Indefinite-lived intangible assets	$	11,348,900	$	10,986,200
Finite-lived intangible assets	728,648		750,193
Total intangible assets	$	12,077,548	$	11,736,393

Schedule of Indefinite-Lived Intangible Assets [Table Text Block]

The following table summarizes our indefinite-lived intangible assets (in thousands):

	March 31, 2013		December 31, 2012
Indefinite-lived intangible asset - Sofosbuvir	$	10,720,000	$	10,720,000
Indefinite-lived intangible asset - Momelotinib (formerly CYT387)	362,700		—
Indefinite-lived intangible assets - Other	266,200		266,200
Total	$	11,348,900	$	10,986,200

Schedule of Finite-Lived Intangible Assets [Table Text Block]

The following table summarizes our finite-lived intangible assets (in thousands):

	March 31, 2013				December 31, 2012
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Intangible asset - Ranexa	$	688,400	$	147,552	$	688,400	$	133,119
Intangible asset - Lexiscan	262,800		101,902		262,800		95,466
Other	42,995		16,093		42,995		15,417
Total	$	994,195	$	265,547	$	994,195	$	244,002

Estimated Future Amortization Expense [Table Text Block]

As of March 31, 2013, the estimated future amortization expense associated with our intangible assets for the remaining nine months of 2013 and each of the five succeeding fiscal years is as follows (in thousands):

Fiscal Year	Amount
2013 (remaining nine months)	$	64,636
2014	92,441
2015	97,673
2016	107,312
2017	116,137
2018	124,561
Total	$	602,760

Schedule of Goodwill [Table Text Block]

The following table summarizes the changes in the carrying amount of goodwill (in thousands):

Balance at December 31, 2012	$	1,060,919
Goodwill resulting from the acquisition of YM	127,238
Balance at March 31, 2013	$	1,188,157

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Intangible Assets and Goodwill Goodwill Rollforward (Details) (USD $) In Thousands, unless otherwise specified			3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 YM Biosciences [Member]
Goodwill [Roll Forward]
Balance at December 31, 2012	$ 1,188,157	$ 1,060,919
Goodwill Resulting from the Acquisition of YM			127,238
Balance at March 31, 2013	$ 1,188,157	$ 1,060,919

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Available-for-Sale Securities Available-for-Sale Securities Narrative (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investments, Debt and Equity Securities [Abstract]
Cash and Cash Equivalents not Including Available-for-Sale Securities	$ 230.8	$ 387.3
Available-for-Sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions (securities)	37	47

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Stock-Based Compensation Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2013

Share-based Compensation [Abstract]

Schedule of Stock-Based Compensation Expenses Included in Consolidated Statement of Income [Text Block]

The following table summarizes the stock-based compensation expense included in our Consolidated Statements of Income (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Cost of goods sold	$	1,841		$	2,101
Research and development expenses	26,875			118,622
Selling, general and administrative expenses	33,051			121,945
Stock-based compensation expense included in total costs and expenses	61,767			242,668
Income tax effect	(16,387		)	(13,064		)
Stock-based compensation expense, net of tax	$	45,380		$	229,604

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Stockholders' Equity Table of Changes in Accumulated Comprehensive Income by Component (Tables)

3 Months Ended

Mar. 31, 2013

Stockholders' Equity Attributable to Parent [Abstract]

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

The following table summarizes the changes in accumulated OCI by component, net of tax (in thousands):

	Foreign Currency Items			Unrealized Gains and Losses on Available-for-Sale Securities			Unrealized Gains and Losses on Cash Flow Hedges			Total
Balance at December 31, 2012	$	30,084		$	(24,002	)	$	(51,697	)	$	(45,615	)
Other comprehensive income (loss) before reclassifications	(8,956		)	1,785			74,060			66,889
Amounts reclassified from accumulated other comprehensive income	—			(17		)	(451		)	(468		)
Net current period other comprehensive income (loss)	(8,956		)	1,768			73,609			66,421
Balance at March 31, 2013	$	21,128		$	(22,234	)	$	21,912		$	20,806

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Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2013

Accounting Policies [Abstract]

Summary of Significant Accounting Policies [Text Block]

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The accompanying unaudited Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles for interim financial information. The financial statements include all adjustments (consisting only of normal recurring adjustments) that the management of Gilead Sciences, Inc. (Gilead, we or us) believes are necessary for a fair presentation of the periods presented. These interim financial results are not necessarily indicative of results expected for the full fiscal year or for any subsequent interim period.

The accompanying Consolidated Financial Statements include the accounts of Gilead, our wholly-owned subsidiaries and our joint ventures with Bristol-Myers Squibb Company (BMS), for which we are the primary beneficiary. We record a noncontrolling interest in our Consolidated Financial Statements to reflect BMS’s interest in the joint ventures. All intercompany transactions have been eliminated. The Consolidated Financial Statements include the results of companies acquired by us from the date of each acquisition for the applicable reporting periods.

The accompanying Consolidated Financial Statements and related financial information should be read in conjunction with the audited Consolidated Financial Statements and the related notes thereto for the year ended December 31, 2012, included in our Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (SEC).

On January 25, 2013, we completed a two-for-one stock split in the form of a stock dividend to stockholders of record as of January 7, 2013, as declared on December 10, 2012. Accordingly, all share and per share amounts for all periods presented in these Consolidated Financial Statements and notes have been adjusted retroactively to reflect this stock split.

Significant Accounting Policies, Estimates and Judgments

The preparation of these Consolidated Financial Statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures. On an ongoing basis, management evaluates its significant accounting policies or estimates. We base our estimates on historical experience and on various market specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ significantly from these estimates.

Net Income Per Share Attributable to Gilead Common Stockholders

Basic net income per share attributable to Gilead common stockholders is calculated based on the weighted-average number of shares of our common stock outstanding during the period. Diluted net income per share attributable to Gilead common stockholders is calculated based on the weighted-average number of shares of our common stock outstanding and other dilutive securities outstanding during the period. The potential dilutive shares of our common stock resulting from the assumed exercise of outstanding stock options, performance shares and the assumed exercise of warrants relating to the convertible senior notes due in May 2013 (May 2013 Notes), May 2014 (May 2014 Notes) and May 2016 (May 2016 Notes) (collectively, the Convertible Notes) are determined under the treasury stock method.

Because the principal amount of the Convertible Notes will be settled in cash, only the conversion spread relating to the Convertible Notes is included in our calculation of diluted net income per share attributable to Gilead common stockholders. Our common stock resulting from the assumed settlement of the conversion spread of the Convertible Notes has a dilutive effect when the average market price of our common stock during the period exceeds the conversion price of $19.05 for the May 2013 Notes, $22.54 for the May 2014 Notes and $22.71 for the May 2016 Notes.

During the three months ended March 31, 2013 and 2012, the average market price of our common stock exceeded the conversion prices of the Convertible Notes and the dilutive effects are included in the accompanying table. During the three months ended March 31, 2013, a portion of the Convertible Notes were converted and as a result, we have only considered their impact for the period they were outstanding.

Warrants relating to the Convertible Notes have a dilutive effect when the average market price of our common stock during the period exceeds the warrants’ exercise price of $26.95 for the May 2013 Notes, $28.38 for the May 2014 Notes and $30.05 for the May 2016 Notes. During the three months ended March 31, 2013, the average market price of our common stock exceeded the warrants' exercise prices relating to the Convertible Notes and the dilutive effect is included in the accompanying table. During the three months ended March 31, 2012, the average market price of our common stock did not exceed the warrants’ exercise prices relating to any of the Convertible Notes; therefore, these warrants did not have a dilutive effect on our net income per share for that period.

Stock options to purchase approximately 1.3 million and 21.8 million weighted-average shares of our common stock were outstanding during the three months ended March 31, 2013 and 2012, respectively, but were not included in the computation of diluted net income per share attributable to Gilead common stockholders because their effect was antidilutive.

The following table is a reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share attributable to Gilead common stockholders (in thousands):

	Three Months Ended
	March 31,
	2013		2012
Numerator:
Net income attributable to Gilead	$	722,186	$	441,956
Denominator:
Weighted-average shares of common stock outstanding used in the calculation of basic net income per share attributable to Gilead common stockholders	1,521,372		1,512,572
Effect of dilutive securities:
Stock options and equivalents	36,812		29,746
Conversion spread related to the May 2013 Notes	10,703		6,846
Conversion spread related to the May 2014 Notes	25,554		3,010
Conversion spread related to the May 2016 Notes	25,140		2,602
Warrants related to the Convertible Notes	45,479		—
Weighted-average shares of common stock outstanding used in the calculation of diluted net income per share attributable to Gilead common stockholders	1,665,060		1,554,776

Concentrations of Risk

We are subject to credit risk from our portfolio of cash equivalents and marketable securities. Under our investment policy, we limit amounts invested in such securities by credit rating, maturity, industry group, investment type and issuer, except for securities issued by the U.S. government. We are not exposed to any significant concentrations of credit risk from these financial instruments. The goals of our investment policy, in order of priority, are as follows: safety and preservation of principal and diversification of risk; liquidity of investments sufficient to meet cash flow requirements; and a competitive after-tax rate of return.

We are also subject to credit risk from our accounts receivable related to our product sales. The majority of our trade accounts receivable arises from product sales in the United States and Europe.

As of March 31, 2013, our accounts receivable in Southern Europe, specifically Greece, Italy, Portugal and Spain, totaled approximately $849.6 million, of which $348.5 million were greater than 120 days past due and $114.1 million were greater than 365 days past due. To date, we have not experienced significant losses with respect to the collection of our accounts receivable. We believe that our allowance for doubtful accounts was adequate at March 31, 2013.

Recent Accounting Pronouncements

In January 2013, the Financial Accounting Standards Board (FASB) issued an update to clarify the scope of disclosures for offsetting assets and liabilities. The update was effective for us beginning in the first quarter of 2013 and was applied retrospectively for all comparative periods presented. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

In February 2013, the FASB issued a new standard to improve the reporting of reclassification adjustments out of accumulated other comprehensive income (OCI). The update requires disclosure of amounts reclassified out of accumulated OCI by component. In addition, if the amount reclassified is required to be reclassified to net income in its entirety in the same reporting period, an entity is required to present significant amounts reclassified out of accumulated OCI by the respective line items of net income. The updated standard was effective for us beginning in the first quarter of 2013. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

In February 2013, the FASB also issued an update to the existing standard for liabilities. The update provides guidance for the recognition, measurement and disclosure of obligations resulting from joint and several liability arrangements. For obligations for which the total amount is fixed at the reporting date, an entity will be required to measure those obligations as the sum of the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. Such entities will also be required to disclose the nature, amount and other significant information about the obligations. This guidance will become effective for us beginning in the first quarter of 2014. We are evaluating the financial statement impact of this guidance. Currently, we do not expect that adopting this update will have a material impact on our Consolidated Financial Statements.

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Segment information Segment information (Tables)

3 Months Ended

Mar. 31, 2013

Segment Reporting [Abstract]

Product Sales by Product [Abstract]

Product sales consist of the following (in thousands):

	Three Months Ended
	March 31,
	2013		2012
Antiviral products:
Atripla	$	877,073	$	887,596
Truvada	700,242		758,263
Viread	210,332		191,693
Complera/Eviplera	148,189		52,180
Stribild	92,148		—
Hepsera	26,423		29,297
Emtriva	6,671		6,777
Total antiviral products	2,061,078		1,925,806
Letairis	118,107		87,288
Ranexa	96,286		83,201
AmBisome	85,275		84,764
Other products	32,822		27,283
Total product sales	$	2,393,568	$	2,208,342

Schedule of Revenue by Major Customers [Table Text Block]

The following table summarizes revenues from each of our customers who individually accounted for 10% or more of our total revenues (as a percentage of total revenues):

	Three Months Ended
	March 31,
	2013		2012
Cardinal Health, Inc.	19	%	20	%
McKesson Corp.	14	%	16	%
AmerisourceBergen Corp.	11	%	11	%

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Available-for-Sale Securities Summary of the Classification of Available-for-Sale Securities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investments, Debt and Equity Securities [Abstract]
Cash And Cash Equivalents	$ 1,633,153	$ 1,416,356
Short-Term Marketable Securities	78,804	58,556
Long-Term Marketable Securities	688,254	719,836
Total	$ 2,400,211	$ 2,194,748

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Intangible Assets and Goodwill Schedule of Indefinite Lived Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 11,348,900	$ 10,986,200
Sofosbuvir [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	10,720,000	10,720,000
CYT387 [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	362,700	0
Other [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 266,200	$ 266,200

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Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Assets [Abstract]
Cash and Cash Equivalents	$ 1,863,972	$ 1,803,694
Short-Term Marketable Securities	78,804	58,556
Accounts Receivable, net	1,945,189	1,751,388
Inventories	1,799,618	1,744,982
Deferred Tax Assets	211,938	262,641
Prepaid Taxes	411,117	348,420
Prepaid Expenses	134,711	102,364
Other Current Assets	217,748	84,302
Total Current Assets	6,663,097	6,156,347
Property, Plant and Equipment, Net	1,125,794	1,100,259
Long-Term Portion of Prepaid Royalties	179,207	175,790
Long-Term Deferred Tax Assets	139,663	131,107
Long-term Marketable Securities	688,254	719,836
Intangible Assets, Net	12,077,548	11,736,393
Goodwill	1,188,157	1,060,919
Other Long-Term Assets	149,948	159,187
Total Assets	22,211,668	21,239,838
Liabilities and Stockholders' Equity [Abstract]
Accounts Payable	1,356,372	1,327,339
Accrued Government Rebates	875,751	745,148
Accrued Compensation and Employee Benefits	152,663	236,716
Income Taxes Payable	19,240	13,403
Other Accrued Liabilities	819,009	674,762
Deferred Revenues	124,369	103,162
Current Portion of Long-Term Debt and Other Obligations, net	942,811	1,169,490
Total Current Liabilities	4,290,215	4,270,020
Long-Term Deferred Revenues	32,204	20,532
Long-Term Debt, net	7,054,796	7,054,555
Long-Term Income Taxes Payable	110,250	115,822
Long-term Deferred Tax Liabilities	118,403	10,190
Other Long-Term Obligations	213,327	217,850
Stockholders' Equity [Abstract]
Preferred Stock, Par Value $0.001 Per Share; 5,000 Shares Authorized; None Outstanding	0	0
Common Stock, Par Value $0.001 Per Share; 2,800,000 Shares Authorized; 1,524,383 and 1,519,163 Shares Issued and Outstanding	760	760
Additional Paid-in Capital	5,829,126	5,649,850
Accumulated Other Comprehensive Income (Loss)	20,806	(45,615)
Retained Earnings	4,301,539	3,704,744
Total Gilead Stockholders' Equity	10,152,231	9,309,739
Noncontrolling Interest	240,242	241,130
Total Stockholders' Equity	10,392,473	9,550,869
Total Liabilities and Stockholders' Equity	$ 22,211,668	$ 21,239,838

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Derivative Financial Instruments Summary of Information about the Fair Values of Derivative Instruments on Consolidated Balance Sheets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Derivative Asset Fair Value	$ 43,182	$ 14,823
Derivative Liability, Fair Value	18,671	65,248
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset Fair Value	42,745	14,698
Derivative Liability, Fair Value	18,021	65,227
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset Fair Value	437	125
Derivative Liability, Fair Value	650	21
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset Fair Value	33,048	14,556
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value	17,915	54,597
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Long-Term Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset Fair Value	9,697	142
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] | Other Long-Term Obligations [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value	106	10,630
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset Fair Value	437	125
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value	$ 650	$ 21

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Consolidated Statements of Comprehensive Income Consolidated Statements of Comprehensive Income Paranthetical (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Available-for-sale Securities [Abstract]
Net Unrealized Gains (Losses), Tax Impact	$ (1,016)	$ 266
Reclassification Adjustments, Tax Impact	(9)	(519)
Cash Flow Hedges [Abstract]
Net Unrealized Gains (Losses), Tax Impact	(1,849)	1,802
Reclassification Adjustments, Tax Impact	$ (11)	$ (400)

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Long-Term Obligations Schedule of Carrying Amounts of Senior Notes (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Total Debt, Net	$ 7,997,555	$ 8,223,988
Less Current Portion	942,759	1,169,433
Total Long-Term Debt, Net	7,054,796	7,054,555
Convertible Senior Notes Due In May 2013 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	0.625%
Convertible Senior Notes	342,759	419,433
Convertible Senior Notes Due In May 2014 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.00%
Convertible Senior Notes	1,211,072	1,210,213
Convertible Senior Notes Due In May 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.625%
Convertible Senior Notes	1,156,632	1,157,692
Senior Unsecured Notes Due In April 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Senior Unsecured Notes	993,138	992,923
Senior Unsecured Notes Due In December 2014 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.40%
Senior Unsecured Notes	749,473	749,394
Senior Unsecured Notes Due In December 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.05%
Senior Unsecured Notes	699,152	699,095
Senior Unsecured Notes Due In December 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.40%
Senior Unsecured Notes	1,247,501	1,247,428
Senior Unsecured Notes Due In December 2041 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.65%
Senior Unsecured Notes	997,828	997,810
Credit Facility Due In January 2017 [Member]
Debt Instrument [Line Items]
Credit Facility, Amount Outstanding	$ 600,000	$ 750,000

XML

Fair value measurements Fair Value and Carrying Value of Debt (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Convertible Senior Notes Due In May 2013 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Convertible Senior Notes, Carrying Value	$ 342,759	$ 419,433
Debt Instruments, Fair Value	825,330	815,297
Convertible Senior Notes Due In May 2014 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Convertible Senior Notes, Carrying Value	1,211,072	1,210,213
Debt Instruments, Fair Value	2,696,870	2,040,363
Convertible Senior Notes Due In May 2016 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Convertible Senior Notes, Carrying Value	1,156,632	1,157,692
Debt Instruments, Fair Value	2,704,726	2,110,938
Senior Unsecured Notes Due In April 2021 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Debt Instruments, Fair Value	1,133,650	1,146,990
Senior Unsecured Notes, Carrying Value	993,138	992,923
Senior Unsecured Notes Due In December 2014 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Debt Instruments, Fair Value	771,398	772,650
Senior Unsecured Notes, Carrying Value	749,473	749,394
Senior Unsecured Notes Due In December 2016 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Debt Instruments, Fair Value	749,784	748,902
Senior Unsecured Notes, Carrying Value	699,152	699,095
Senior Unsecured Notes Due In December 2021 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Debt Instruments, Fair Value	1,405,125	1,420,725
Senior Unsecured Notes, Carrying Value	1,247,501	1,247,428
Senior Unsecured Notes Due In December 2041 [Member]
Fair Value and Carrying Value of Debt [Line Items]
Debt Instruments, Fair Value	1,208,000	1,252,090
Senior Unsecured Notes, Carrying Value	$ 997,828	$ 997,810

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Segment information Segment reporting information, revenue for reportable segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Information [Line Items]
Product Sales	$ 2,393,568	$ 2,208,342
Atripla [Member]
Segment Reporting Information [Line Items]
Product Sales	877,073	887,596
Truvada [Member]
Segment Reporting Information [Line Items]
Product Sales	700,242	758,263
Viread [Member]
Segment Reporting Information [Line Items]
Product Sales	210,332	191,693
Complera/Eviplera [Member]
Segment Reporting Information [Line Items]
Product Sales	148,189	52,180
Stribild [Member]
Segment Reporting Information [Line Items]
Product Sales	92,148	0
Hepsera [Member]
Segment Reporting Information [Line Items]
Product Sales	26,423	29,297
Emtriva [Member]
Segment Reporting Information [Line Items]
Product Sales	6,671	6,777
Total Antiviral Products [Member]
Segment Reporting Information [Line Items]
Product Sales	2,061,078	1,925,806
Letairis [Member]
Segment Reporting Information [Line Items]
Product Sales	118,107	87,288
Ranexa [Member]
Segment Reporting Information [Line Items]
Product Sales	96,286	83,201
Ambisome [Member]
Segment Reporting Information [Line Items]
Product Sales	85,275	84,764
Other Products [Member]
Segment Reporting Information [Line Items]
Product Sales	$ 32,822	$ 27,283

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Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2013

Accounting Policies [Abstract]

Basis of Presentation [Text Block]

Basis of Presentation

The accompanying unaudited Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles for interim financial information. The financial statements include all adjustments (consisting only of normal recurring adjustments) that the management of Gilead Sciences, Inc. (Gilead, we or us) believes are necessary for a fair presentation of the periods presented. These interim financial results are not necessarily indicative of results expected for the full fiscal year or for any subsequent interim period.

The accompanying Consolidated Financial Statements include the accounts of Gilead, our wholly-owned subsidiaries and our joint ventures with Bristol-Myers Squibb Company (BMS), for which we are the primary beneficiary. We record a noncontrolling interest in our Consolidated Financial Statements to reflect BMS’s interest in the joint ventures. All intercompany transactions have been eliminated. The Consolidated Financial Statements include the results of companies acquired by us from the date of each acquisition for the applicable reporting periods.

The accompanying Consolidated Financial Statements and related financial information should be read in conjunction with the audited Consolidated Financial Statements and the related notes thereto for the year ended December 31, 2012, included in our Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (SEC).

On January 25, 2013, we completed a two-for-one stock split in the form of a stock dividend to stockholders of record as of January 7, 2013, as declared on December 10, 2012. Accordingly, all share and per share amounts for all periods presented in these Consolidated Financial Statements and notes have been adjusted retroactively to reflect this stock split.

Significant Accounting Policies, Estimates and Judgments [Policy Text Block]

Significant Accounting Policies, Estimates and Judgments

The preparation of these Consolidated Financial Statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures. On an ongoing basis, management evaluates its significant accounting policies or estimates. We base our estimates on historical experience and on various market specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ significantly from these estimates.

Net Income Per Share Attributable to Gilead Common Stockholders [Policy Text Block]

Net Income Per Share Attributable to Gilead Common Stockholders

Basic net income per share attributable to Gilead common stockholders is calculated based on the weighted-average number of shares of our common stock outstanding during the period. Diluted net income per share attributable to Gilead common stockholders is calculated based on the weighted-average number of shares of our common stock outstanding and other dilutive securities outstanding during the period. The potential dilutive shares of our common stock resulting from the assumed exercise of outstanding stock options, performance shares and the assumed exercise of warrants relating to the convertible senior notes due in May 2013 (May 2013 Notes), May 2014 (May 2014 Notes) and May 2016 (May 2016 Notes) (collectively, the Convertible Notes) are determined under the treasury stock method.

Because the principal amount of the Convertible Notes will be settled in cash, only the conversion spread relating to the Convertible Notes is included in our calculation of diluted net income per share attributable to Gilead common stockholders. Our common stock resulting from the assumed settlement of the conversion spread of the Convertible Notes has a dilutive effect when the average market price of our common stock during the period exceeds the conversion price of $19.05 for the May 2013 Notes, $22.54 for the May 2014 Notes and $22.71 for the May 2016 Notes.

During the three months ended March 31, 2013 and 2012, the average market price of our common stock exceeded the conversion prices of the Convertible Notes and the dilutive effects are included in the accompanying table. During the three months ended March 31, 2013, a portion of the Convertible Notes were converted and as a result, we have only considered their impact for the period they were outstanding.

Warrants relating to the Convertible Notes have a dilutive effect when the average market price of our common stock during the period exceeds the warrants’ exercise price of $26.95 for the May 2013 Notes, $28.38 for the May 2014 Notes and $30.05 for the May 2016 Notes. During the three months ended March 31, 2013, the average market price of our common stock exceeded the warrants' exercise prices relating to the Convertible Notes and the dilutive effect is included in the accompanying table. During the three months ended March 31, 2012, the average market price of our common stock did not exceed the warrants’ exercise prices relating to any of the Convertible Notes; therefore, these warrants did not have a dilutive effect on our net income per share for that period.

Stock options to purchase approximately 1.3 million and 21.8 million weighted-average shares of our common stock were outstanding during the three months ended March 31, 2013 and 2012, respectively, but were not included in the computation of diluted net income per share attributable to Gilead common stockholders because their effect was antidilutive.

The following table is a reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share attributable to Gilead common stockholders (in thousands):

	Three Months Ended
	March 31,
	2013		2012
Numerator:
Net income attributable to Gilead	$	722,186	$	441,956
Denominator:
Weighted-average shares of common stock outstanding used in the calculation of basic net income per share attributable to Gilead common stockholders	1,521,372		1,512,572
Effect of dilutive securities:
Stock options and equivalents	36,812		29,746
Conversion spread related to the May 2013 Notes	10,703		6,846
Conversion spread related to the May 2014 Notes	25,554		3,010
Conversion spread related to the May 2016 Notes	25,140		2,602
Warrants related to the Convertible Notes	45,479		—
Weighted-average shares of common stock outstanding used in the calculation of diluted net income per share attributable to Gilead common stockholders	1,665,060		1,554,776

Concentrations of Risk [Text Block]

Concentrations of Risk

We are subject to credit risk from our portfolio of cash equivalents and marketable securities. Under our investment policy, we limit amounts invested in such securities by credit rating, maturity, industry group, investment type and issuer, except for securities issued by the U.S. government. We are not exposed to any significant concentrations of credit risk from these financial instruments. The goals of our investment policy, in order of priority, are as follows: safety and preservation of principal and diversification of risk; liquidity of investments sufficient to meet cash flow requirements; and a competitive after-tax rate of return.

We are also subject to credit risk from our accounts receivable related to our product sales. The majority of our trade accounts receivable arises from product sales in the United States and Europe.

As of March 31, 2013, our accounts receivable in Southern Europe, specifically Greece, Italy, Portugal and Spain, totaled approximately $849.6 million, of which $348.5 million were greater than 120 days past due and $114.1 million were greater than 365 days past due. To date, we have not experienced significant losses with respect to the collection of our accounts receivable. We believe that our allowance for doubtful accounts was adequate at March 31, 2013.

Recent Accounting Pronouncement [Policy Text Block]

Recent Accounting Pronouncements

In January 2013, the Financial Accounting Standards Board (FASB) issued an update to clarify the scope of disclosures for offsetting assets and liabilities. The update was effective for us beginning in the first quarter of 2013 and was applied retrospectively for all comparative periods presented. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

In February 2013, the FASB issued a new standard to improve the reporting of reclassification adjustments out of accumulated other comprehensive income (OCI). The update requires disclosure of amounts reclassified out of accumulated OCI by component. In addition, if the amount reclassified is required to be reclassified to net income in its entirety in the same reporting period, an entity is required to present significant amounts reclassified out of accumulated OCI by the respective line items of net income. The updated standard was effective for us beginning in the first quarter of 2013. The adoption of this guidance did not have a material impact on our Consolidated Financial Statements.

In February 2013, the FASB also issued an update to the existing standard for liabilities. The update provides guidance for the recognition, measurement and disclosure of obligations resulting from joint and several liability arrangements. For obligations for which the total amount is fixed at the reporting date, an entity will be required to measure those obligations as the sum of the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. Such entities will also be required to disclose the nature, amount and other significant information about the obligations. This guidance will become effective for us beginning in the first quarter of 2014. We are evaluating the financial statement impact of this guidance. Currently, we do not expect that adopting this update will have a material impact on our Consolidated Financial Statements.

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Fair value measurements Fair value measurements (Summary of assets and liabilities recorded at fair value) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	$ 2,400,211	$ 2,194,748
Derivatives, assets	43,182	14,823
Fair value, total	2,443,393	2,209,571
Contingent consideration	211,084	205,060
Derivatives, liabilities	18,671	65,248
Fair value, total	229,755	270,308
US Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	95,855	81,903
Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	1,633,153	1,416,355
U.S. government agencies securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	218,038	248,952
Municipal Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	12,115	12,088
Corporate Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	355,063	352,718
Residential Mortgage and Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	85,987	82,732
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	1,729,008	1,498,258
Derivatives, assets	0	0
Fair value, total	1,729,008	1,498,258
Contingent consideration	0	0
Derivatives, liabilities	0	0
Fair value, total	0	0
Level 1 [Member] | US Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	95,855	81,903
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	1,633,153	1,416,355
Level 1 [Member] | U.S. government agencies securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 1 [Member] | Municipal Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 1 [Member] | Corporate Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 1 [Member] | Residential Mortgage and Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	671,203	696,490
Derivatives, assets	43,182	14,823
Fair value, total	714,385	711,313
Contingent consideration	0	0
Derivatives, liabilities	18,671	65,248
Fair value, total	18,671	65,248
Level 2 [Member] | US Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 2 [Member] | Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 2 [Member] | U.S. government agencies securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	218,038	248,952
Level 2 [Member] | Municipal Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	12,115	12,088
Level 2 [Member] | Corporate Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	355,063	352,718
Level 2 [Member] | Residential Mortgage and Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	85,987	82,732
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Derivatives, assets	0	0
Fair value, total	0	0
Contingent consideration	211,084	205,060
Derivatives, liabilities	0	0
Fair value, total	211,084	205,060
Level 3 [Member] | US Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 3 [Member] | Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 3 [Member] | U.S. government agencies securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 3 [Member] | Municipal Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 3 [Member] | Corporate Debt Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	0	0
Level 3 [Member] | Residential Mortgage and Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated Fair Value	$ 0	$ 0

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Fair value measurements Fair value measurements (Tables)

3 Months Ended

Mar. 31, 2013

Fair Value Disclosures [Abstract]

Fair Values and Carrying Values of Debt [Table Text Block]

The following table summarizes the carrying values and fair values of the Convertible Notes and senior unsecured notes (in thousands):

		March 31, 2013				December 31, 2012
Type of Borrowing	Description	Carrying Value		Fair Value		Carrying Value		Fair Value
Convertible Senior	May 2013 Notes	$	342,759	$	825,330	$	419,433	$	815,297
Convertible Senior	May 2014 Notes	1,211,072		2,696,870		1,210,213		2,040,363
Convertible Senior	May 2016 Notes	1,156,632		2,704,726		1,157,692		2,110,938
Senior Unsecured	April 2021 Notes	993,138		1,133,650		992,923		1,146,990
Senior Unsecured	December 2014 Notes	749,473		771,398		749,394		772,650
Senior Unsecured	December 2016 Notes	699,152		749,784		699,095		748,902
Senior Unsecured	December 2021 Notes	1,247,501		1,405,125		1,247,428		1,420,725
Senior Unsecured	December 2041 Notes	997,828		1,208,000		997,810		1,252,090

Schedule of fair value, assets and liabilities measured on recurring basis [Table Text Block]

The following table summarizes, for assets or liabilities recorded at fair value, the respective fair value and the classification by level of input within the fair value hierarchy defined above (in thousands):

	March 31, 2013								December 31, 2012
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Assets:
Debt securities:
U.S. treasury securities	$	95,855	$	—	$	—	$	95,855	$	81,903	$	—	$	—	$	81,903
Money market funds	1,633,153		—		—		1,633,153		1,416,355		—		—		1,416,355
U.S. government agencies securities	—		218,038		—		218,038		—		248,952		—		248,952
Municipal debt securities	—		12,115		—		12,115		—		12,088		—		12,088
Corporate debt securities	—		355,063		—		355,063		—		352,718		—		352,718
Residential mortgage and asset-backed securities	—		85,987		—		85,987		—		82,732		—		82,732
Total debt securities	1,729,008		671,203		—		2,400,211		1,498,258		696,490		—		2,194,748
Derivatives	—		43,182		—		43,182		—		14,823		—		14,823
	$	1,729,008	$	714,385	$	—	$	2,443,393	$	1,498,258	$	711,313	$	—	$	2,209,571
Liabilities:
Contingent consideration	$	—	$	—	$	211,084	$	211,084	$	—	$	—	$	205,060	$	205,060
Derivatives	—		18,671		—		18,671		—		65,248		—		65,248
	$	—	$	18,671	$	211,084	$	229,755	$	—	$	65,248	$	205,060	$	270,308

Fair value, liabilities measured on recurring basis, unobservable input reconciliation [Table Text Block]

The following table provides a rollforward of our contingent consideration liabilities, which are recorded as part of other long-term obligations in our Consolidated Balance Sheets (in thousands):

Balance at December 31, 2012	$	205,060
Additions from new acquisitions	—
Net changes in valuation	6,024
Balance at March 31, 2013	$	211,084

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Income Taxes Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Effective Income Tax Rate, Continuing Operations	23.70%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	35.00%
Unrecognized Tax Benefits, Decreases Resulting from Prior Period Tax Positions	$ 18

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Statement of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating Activities [Abstract]
Net Income	$ 717,710	$ 437,531
Adjustments to Reconcile Net Income to Cash Provided by Operating Activities [Abstract]
Depreciation Expense	23,973	19,710
Amortization Expense	50,353	46,457
Stock-Based Compensation Expense	61,767	48,731
Excess Tax Benefits from Stock-Based Compensation	(40,746)	(23,304)
Tax Benefits from Employee Stock Plans	38,905	18,153
Deferred Income Taxes	39,301	51,385
Other	8,262	13,767
Changes in Operating Assets and Liabilities [Abstract]
Accounts Receivable, net	(231,781)	(196,531)
Inventories	(57,109)	(26,833)
Prepaid Expense and Other Assets	(187,304)	(75,176)
Accounts Payable	30,792	107,652
Income Taxes Payable	12,056	(99,151)
Accrued Liabilities	173,042	110,402
Deferred Revenues	32,880	20,176
Net Cash Provided by Operating Activities	672,101	452,969
Investing Activities [Abstract]
Purchases of Marketable Securities	(62,604)	0
Proceeds from Sales of Marketable Securities	65,985	56,719
Proceeds from Maturities of Marketable Securities	6,862	0
Purchases of Other Investments	0	(25,000)
Acquisitions, Net of Cash Acquired	(378,645)	(10,751,636)
Capital Expenditures	(38,854)	(23,199)
Net Cash Used in Investing Activities	(407,256)	(10,743,116)
Financing Activities [Abstract]
Proceeds from Debt Financing, Net of Issuance Costs	0	2,144,733
Proceeds from Convertible Note Hedges	100,771	0
Proceeds from Issuances of Common Stock	86,049	132,530
Repurchases of Common Stock	(82,239)	(20,770)
Repayments of Debt Financing	(347,896)	(350,000)
Repayments of Other Long-Term Obligations	(20)	(612)
Excess Tax Benefits from Stock-Based Compensation	40,746	23,304
Contributions From (Distributions to) Noncontrolling Interest	3,588	(73,595)
Net Cash Provided by (Used in) Financing Activities	(199,001)	1,855,590
Effect of Exchange Rate Changes on Cash	(5,566)	2,722
Net Change in Cash and Cash Equivalents	60,278	(8,431,835)
Cash and Cash Equivalents at beginning of period	1,803,694	9,883,777
Cash and Cash Equivalents at end of period	$ 1,863,972	$ 1,451,942

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Consolidated Balance Sheets Paranthetical (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Preferred Stock, Par Value (usd per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	5,000	5,000
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par Value (usd per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized	2,800,000	2,800,000
Common Stock, Shares Issued	1,524,383	1,519,163
Common Stock, Shares Outstanding	1,524,383	1,519,163

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Commitment and Contingencies

3 Months Ended

Mar. 31, 2013

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies Disclosure [Text Block]

COMMITMENTS AND CONTINGENCIES

Legal Proceedings

Department of Justice Investigation

In June 2011, we received a subpoena from the U.S. Attorney's Office for the Northern District of California requesting documents related to the manufacture, and related quality and distribution practices, of Atripla, Emtriva, Hepsera, Letairis, Truvada, Viread and Complera. We have been cooperating and will continue to cooperate with this governmental inquiry. An estimate of a possible loss or range of losses cannot be determined.

Litigation with Generic Manufacturers

As part of the approval process of some of our products, the U.S. Food and Drug Administration (FDA) granted a New Chemical Entity (NCE) exclusivity period during which other manufacturers' applications for approval of generic versions of our product will not be granted. Generic manufacturers may challenge the patents protecting products that have been granted exclusivity one year prior to the end of the exclusivity period. Generic manufacturers have sought and may continue to seek FDA approval for a similar or identical drug through an abbreviated new drug application (ANDA), the application form typically used by manufacturers seeking approval of a generic drug.

We received notices that generic manufacturers have submitted ANDAs to manufacture a generic version of Atripla, Truvada, Viread, Hepsera, Ranexa and Tamiflu in the United States and Atripla, Truvada and Viread in Canada. We expect to begin trial with some of the generic manufacturers in 2013. In February 2013, Gilead and Teva reached an agreement in principle to settle the ongoing patent litigation concerning the four patents that protect tenofovir disoproxil fumarate in our Viread, Truvada and Atripla products. Under the agreement, Teva will be allowed to launch a generic version of Viread on December 15, 2017. The settlement agreement was recently filed with the Federal Trade Commission (FTC) and Department of Justice (DOJ) and will be final after 45 days if the FTC and DOJ do not object. As a result of the recent invalidation of the patents protecting entecavir and due to declining sales of Hepsera in the United States, in March 2013, we granted Sigmapharm Labs (Sigmapharm) a Covenant Not to Sue if it launches a generic version of Hepsera prior to the expiration of our patents and then filed a motion to dismiss all claims in the lawsuit related to the Hepsera patents. Once Sigmapharm obtains FDA approval of its product, it may launch its generic product. The trial related to ten of the patents associated with Ranexa is scheduled to begin in April 2013. This trial related to three of the patents associated with Truvada in Canada is currently scheduled for hearing in September 2013. The trial related to the two patents protecting emtricitabine patent in our Atripla is scheduled to begin in October 2013.

We cannot predict the ultimate outcome of these actions, and we may spend significant resources enforcing and defending these patents. If we are unsuccessful in these lawsuits, some or all of our original claims in the patents may be narrowed or invalidated and the patent protection for Atripla, Truvada, Viread Ranexa and Tamiflu in the United States and Atripla, Truvada and Viread in Canada could be substantially shortened. Further, if all of the patents covering one or more products are invalidated, the FDA or Canadian Ministry of Health could approve the requests to manufacture a generic version of such products in the United States or Canada, respectively, prior to the expiration date of those patents. The sale of generic versions of these products earlier than their patent expiration would have a significant negative effect on our revenues and results of operations.

Other Matters

We are a party to various legal actions that arose in the ordinary course of our business. We do not believe that any of these legal actions will have a material adverse impact on our consolidated business, financial position or results of operations.

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Document and Entity Information Document	3 Months Ended
	Mar. 31, 2013	Apr. 26, 2013
Document And Entity Information [Abstract]
Entity Registrant Name	Gilead Sciences Inc
Entity Central Index Key	0000882095
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q1
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Amendment Flag	false
Entity Common Stock, Shares Outstanding		1,525,355,825
Entity Current Reporting Status	Yes

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Stock-Based Compensation

3 Months Ended

Mar. 31, 2013

Share-based Compensation [Abstract]

Stock-Based Compensation Disclosure [Text Block]

STOCK-BASED COMPENSATION

The following table summarizes the stock-based compensation expense included in our Consolidated Statements of Income (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Cost of goods sold	$	1,841		$	2,101
Research and development expenses	26,875			118,622
Selling, general and administrative expenses	33,051			121,945
Stock-based compensation expense included in total costs and expenses	61,767			242,668
Income tax effect	(16,387		)	(13,064		)
Stock-based compensation expense, net of tax	$	45,380		$	229,604

Total stock-based compensation for the three months ended March 31, 2012 included $100.1 million and $93.8 million in R&D and selling, general and administrative expenses, respectively, related to the acceleration of unvested stock options in connection with the acquisition of Pharmasset, which closed during the first quarter of 2012.

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Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenues [Abstract]
Product Sales	$ 2,393,568	$ 2,208,342
Royalty Revenues	134,407	71,105
Contract and Other Revenues	3,660	3,002
Total Revenues	2,531,635	2,282,449
Costs and Expenses [Abstract]
Cost of Goods Sold	634,448	580,931
Research and Development	497,632	458,211
Selling, General and Administrative	374,296	443,121
Total Costs and Expenses	1,506,376	1,482,263
Income from Operations	1,025,259	800,186
Interest Expense	(81,787)	(97,270)
Other Income (Expense), net	(3,324)	(34,085)
Income Before Provision for Income Taxes	940,148	668,831
Provision for Income Taxes	222,438	231,300
Net Income	717,710	437,531
Net Loss Attributable to Noncontrolling Interest	4,476	4,425
Net Income Attributable to Gilead	$ 722,186	$ 441,956
Net Income Per Share Attributable to Gilead Common Stockholders - Basic (usd per share)	$ 0.47	$ 0.29
Shares Used in Per Share Calculation-Basic (shares)	1,521,372	1,512,572
Net Income Per Share Attributable to Gilead Common Stockholders - Diluted (usd per share)	$ 0.43	$ 0.28
Shares Used in Per Share Calculation - Diluted (shares)	1,665,060	1,554,776

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Acquisition

3 Months Ended

Mar. 31, 2013

Business Combinations [Abstract]

Business Combination Disclosure [Text Block]

ACQUISITION

YM BioSciences Inc.

We completed the acquisition of YM BioSciences Inc. (YM) for total consideration transferred of $487.6 million on February 8, 2013, at which time YM became a wholly-owned subsidiary of Gilead. YM was a drug development company primarily focused on advancing momelotinib (formally known as CYT387), an orally administered, once-daily candidate for hematologic cancers.

Currently, the purchase accounting is preliminary as management is in the process of reviewing the forecasts that support the valuation. We expect to finalize the purchase accounting during the second quarter of 2013. The preliminary fair values of acquired assets and assumed liabilities include primarily, in-process research and development (IPR&D) of $362.7 million, goodwill of $127.2 million, deferred tax liabilities of $108.8 million and cash acquired of $108.9 million. Pro forma results of operations for the acquisition of YM have not been presented because this acquisition is not material to our consolidated results of operations. See Note 7, Intangible Assets and Goodwill for a description of the IPR&D acquired.

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Derivative Financial Instruments

3 Months Ended

Mar. 31, 2013

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative Financial Instruments

DERIVATIVE FINANCIAL INSTRUMENTS

We operate in foreign countries, which exposes us to market risk associated with foreign currency exchange rate fluctuations between the U.S. dollar and various foreign currencies, the most significant of which is the Euro. In order to manage this risk, we may hedge a portion of our foreign currency exposures related to outstanding monetary assets and liabilities as well as forecasted product sales using foreign currency exchange forward or option contracts. In general, the market risk related to these contracts is offset by corresponding gains and losses on the hedged transactions. The credit risk associated with these contracts is driven by changes in interest and currency exchange rates and, as a result, varies over time. By working only with major banks and closely monitoring current market conditions, we limit the risk that counterparties to these contracts may be unable to perform. We also limit our risk of loss by entering into contracts that permit net settlement at maturity. Therefore, our overall risk of loss in the event of a counterparty default is limited to the amount of any unrecognized gains on outstanding contracts (i.e., those contracts that have a positive fair value) at the date of default. We do not enter into derivative contracts for trading purposes, nor do we hedge our net investment in any of our foreign subsidiaries.

We hedge our exposure to foreign currency exchange rate fluctuations for certain monetary assets and liabilities of our foreign subsidiaries that are denominated in a non-functional currency. The derivative instruments we use to hedge this exposure are not designated as hedges, and as a result, changes in their fair value are recorded in other income (expense), net on our Consolidated Statements of Income.

We hedge our exposure to foreign currency exchange rate fluctuations for forecasted product sales that are denominated in a non-functional currency. The derivative instruments we use to hedge this exposure are designated as cash flow hedges and have maturity dates of 18 months or less. Upon executing a hedging contract and quarterly thereafter, we assess prospective hedge effectiveness using a regression analysis which calculates the change in cash flow as a result of the hedge instrument. On a monthly basis, we assess retrospective hedge effectiveness using a dollar offset approach. We exclude time value from our effectiveness testing and recognize changes in the time value of the hedge in other income (expense), net. The effective component of our hedge is recorded as an unrealized gain or loss on the hedging instrument in accumulated OCI within stockholders' equity. When the hedged forecasted transaction occurs, the hedge is de-designated and the unrealized gains or losses are reclassified into product sales. The majority of gains and losses related to the hedged forecasted transactions reported in accumulated OCI at March 31, 2013 will be reclassified to product sales within 12 months. The cash flow effects of our derivatives contracts for the three months ended March 31, 2013 and 2012 are included within net cash provided by operating activities in the Consolidated Statements of Cash Flows.

We had notional amounts on foreign currency exchange contracts outstanding of $3.47 billion and $3.39 billion at March 31, 2013 and December 31, 2012, respectively.

While all of our derivative contracts allow us the right to offset assets or liabilities, we have presented amounts on a gross basis. Under the International Swap Dealers Association, Inc. master agreements with the respective counterparties of the foreign currency exchange contracts, subject to applicable requirements, we are allowed to net settle transactions of the same currency with a single net amount payable by one party to the other. The following table summarizes the location and fair values of derivative instruments on our Consolidated Balance Sheets (in thousands):

	March 31, 2013
	Asset Derivatives			Liability Derivatives
	Classification	Fair Value		Classification	Fair Value
Derivatives designated as hedges:
Foreign currency exchange contracts	Other current assets	$	33,048	Other accrued liabilities	$	17,915
Foreign currency exchange contracts	Other long-term assets	9,697		Other long-term obligations	106
Total derivatives designated as hedges		42,745			18,021
Derivatives not designated as hedges:
Foreign currency exchange contracts	Other current assets	437		Other accrued liabilities	650
Total derivatives not designated as hedges		437			650
Total derivatives		$	43,182		$	18,671

	December 31, 2012
	Asset Derivatives			Liability Derivatives
	Classification	Fair Value		Classification	Fair Value
Derivatives designated as hedges:
Foreign currency exchange contracts	Other current assets	$	14,556	Other accrued liabilities	$	54,597
Foreign currency exchange contracts	Other long-term assets	142		Other long-term obligations	10,630
Total derivatives designated as hedges		14,698			65,227
Derivatives not designated as hedges:
Foreign currency exchange contracts	Other current assets	125		Other accrued liabilities	21
Total derivatives not designated as hedges		125			21
Total derivatives		$	14,823		$	65,248

The following table summarizes the effect of our foreign currency exchange contracts on our Consolidated Statements of Income (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Derivatives designated as hedges:
Net gains (losses) recognized in OCI (effective portion)	$	70,860		$	(48,886	)
Net gains reclassified from accumulated OCI into product sales (effective portion)	$	462		$	11,227
Losses recognized in other income (expense), net (ineffective portion and amounts excluded from effectiveness testing)	$	(2,132	)	$	(3,212	)
Derivatives not designated as hedges:
Net gains (losses) recognized in other income (expense), net	$	32,620		$	(27,174	)

There were no material amounts recorded in other income (expense), net, for the three months ended March 31, 2013 and 2012 as a result of the discontinuance of cash flow hedges.

As of March 31, 2013 and December 31, 2012, we held one type of financial instrument, derivative contracts related to foreign currency exchange contracts. The following table summarizes the potential effect of offsetting derivatives by type of financial instrument on our Consolidated Balance Sheets (in thousands):

March 31, 2013
Offsetting of Derivative Assets/Liabilities
									Gross Amounts Not Offset in the Consolidated Balance Sheet
Description	Gross Amounts of Recognized Assets/Liabilities			Gross Amounts Offset in the Consolidated Balance Sheet		Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheet			Derivative Financial Instruments			Cash Collateral Received/Pledged		Net Amount (Legal Offset)
Derivative assets	$	43,182		$	—	$	43,182		$	(18,515	)	$	—	$	24,667
Derivative liabilities	(18,671		)	—		(18,671		)	18,515			—		(156		)

December 31, 2012
Offsetting of Derivative Assets/Liabilities
									Gross Amounts Not Offset in the Consolidated Balance Sheet
Description	Gross Amounts of Recognized Assets/Liabilities			Gross Amounts Offset in the Consolidated Balance Sheet		Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheet			Derivative Financial Instruments			Cash Collateral Received/Pledged		Net Amount (Legal Offset)
Derivative assets	$	14,823		$	—	$	14,823		$	(9,644	)	$	—	$	5,179
Derivative liabilities	(65,248		)	—		(65,248		)	9,644			—		(55,604		)

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Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2013

Accounting Policies [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

The following table is a reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share attributable to Gilead common stockholders (in thousands):

	Three Months Ended
	March 31,
	2013		2012
Numerator:
Net income attributable to Gilead	$	722,186	$	441,956
Denominator:
Weighted-average shares of common stock outstanding used in the calculation of basic net income per share attributable to Gilead common stockholders	1,521,372		1,512,572
Effect of dilutive securities:
Stock options and equivalents	36,812		29,746
Conversion spread related to the May 2013 Notes	10,703		6,846
Conversion spread related to the May 2014 Notes	25,554		3,010
Conversion spread related to the May 2016 Notes	25,140		2,602
Warrants related to the Convertible Notes	45,479		—
Weighted-average shares of common stock outstanding used in the calculation of diluted net income per share attributable to Gilead common stockholders	1,665,060		1,554,776

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Stockholders' Equity

3 Months Ended

Mar. 31, 2013

Stockholders' Equity Attributable to Parent [Abstract]

Stockholders' Equity Note Disclosure [Text Block]

STOCKHOLDERS’ EQUITY

Stock Repurchase Program

During the three months ended March 31, 2013, we repurchased a total of $82.2 million or 2.1 million shares of common stock under our January 2011, three-year, $5.00 billion stock repurchase program.

Accumulated Other Comprehensive Income

The following table summarizes the changes in accumulated OCI by component, net of tax (in thousands):

	Foreign Currency Items			Unrealized Gains and Losses on Available-for-Sale Securities			Unrealized Gains and Losses on Cash Flow Hedges			Total
Balance at December 31, 2012	$	30,084		$	(24,002	)	$	(51,697	)	$	(45,615	)
Other comprehensive income (loss) before reclassifications	(8,956		)	1,785			74,060			66,889
Amounts reclassified from accumulated other comprehensive income	—			(17		)	(451		)	(468		)
Net current period other comprehensive income (loss)	(8,956		)	1,768			73,609			66,421
Balance at March 31, 2013	$	21,128		$	(22,234	)	$	21,912		$	20,806

For the three months ended March 31, 2013, amounts reclassified from accumulated OCI were not significant. Amounts reclassified for gains (losses) on cash flow hedges were recorded as part of product sales on our Consolidated Statements of Income. Amounts reclassified for unrealized gains (losses) on available-for-sale securities were recorded as part of other income (expense), net on our Consolidated Statements of Income.

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Collaborative Arrangements

3 Months Ended

Mar. 31, 2013

Collaborative Arrangements [Abstract]

Collaborative Arrangement Disclosure [Text Block]

COLLABORATIVE ARRANGEMENTS

From time to time, as a result of entering into strategic collaborations, we may hold investments in non-public companies. We review our interests in investee companies for consolidation and/or appropriate disclosure based on applicable guidance. For variable interest entities (VIEs), we may be required to consolidate an entity if the contractual terms of the arrangement essentially provide us with control over the entity, even if we do not have a majority voting interest. We assess whether we are the primary beneficiary of a VIE based on our power to direct the activities of the VIE that most significantly impact the VIE's economic performance and our obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE. As of March 31, 2013, we determined that certain of our investee companies are VIEs; however, other than with respect to our joint ventures with BMS, we are not the primary beneficiary and therefore do not consolidate these investees.

Bristol-Myers Squibb Company

North America

In 2004, we entered into a collaboration arrangement with BMS in the United States to develop and commercialize a single tablet regimen containing our Truvada and BMS's Sustiva (efavirenz). This combination was approved for use in the United States in 2006 and is sold under the brand name Atripla. We and BMS structured this collaboration as a joint venture that operates as a limited liability company named Bristol-Myers Squibb & Gilead Sciences, LLC, which we consolidate. Under the terms of the collaboration we and BMS granted royalty free sublicenses to the joint venture for the use of our respective company owned technologies and, in return, were granted a license by the joint venture to use any intellectual property that results from the collaboration. In 2006, we and BMS amended the joint venture's collaboration agreement to allow the joint venture to sell Atripla into Canada. The economic interests of the joint venture held by us and BMS (including share of revenues and out-of-pocket expenses) is based on the portion of the net selling price of Atripla attributable to efavirenz and Truvada. Since the net selling price for Truvada may change over time relative to the net selling price of efavirenz, both our and BMS's respective economic interests in the joint venture may vary annually.

We and BMS shared marketing and sales efforts. Since the second quarter of 2011, except for a limited number of activities that will be jointly managed, the parties no longer coordinate detailing and promotional activities in the United States, and the parties have begun to reduce their joint promotional efforts since we launched Complera in August 2011 and Stribild in August 2012. The parties will continue to collaborate on activities such as manufacturing, regulatory, compliance and pharmacovigilance. The daily operations of the joint venture are governed by four primary joint committees formed by both BMS and Gilead. We are responsible for accounting, financial reporting, tax reporting, manufacturing and product distribution for the joint venture. Both parties provide their respective bulk active pharmaceutical ingredients to the joint venture at their approximate market values. The agreement will continue until terminated by the mutual agreement of the parties. In addition, either party may terminate the other party's participation in the collaboration within 30 days after the launch of at least one generic version of such other party's single agent products (or the double agent products). The non-terminating party then has the right to continue to sell Atripla, but will be obligated to pay the terminating party certain royalties for a three-year period following the effective date of the termination.

As of March 31, 2013 and December 31, 2012, the joint venture held efavirenz active pharmaceutical ingredient which it purchased from BMS at BMS's estimated net selling price of efavirenz in the U.S. market. These amounts are included in inventories on our Consolidated Balance Sheets. As of March 31, 2013, total assets held by the joint venture were $2.24 billion and consisted primarily of cash and cash equivalents of $147.7 million, accounts receivable of $291.7 million and inventories of $1.74 billion; total liabilities were $1.61 billion and consisted primarily of accounts payable of $569.9 million and other accrued expenses of $367.3 million. As of December 31, 2012, total assets held by the joint venture were $1.95 billion and consisted primarily of cash and cash equivalents of $191.1 million, accounts receivable of $223.7 million and inventories of $1.54 billion; total liabilities were $1.32 billion and consisted primarily of accounts payable of $501.7 million and other accrued expenses of $291.5 million. These asset and liability amounts do not reflect the impact of intercompany eliminations that are included in our Consolidated Balance Sheets. Although we consolidate the joint venture, the legal structure of the joint venture limits the recourse that its creditors will have over our general credit or assets. Similarly, the assets held in the joint venture can be used only to settle obligations of the joint venture.

Europe

In 2007, Gilead Sciences Limited, our wholly-owned subsidiary in Ireland, and BMS entered into a collaboration agreement with BMS which sets forth the terms and conditions under which we and BMS will commercialize and distribute Atripla in the European Union, Iceland, Liechtenstein, Norway and Switzerland (collectively, the European Territory). The parties formed a limited liability company which we consolidate, to manufacture Atripla for distribution in the European Territory using efavirenz that it purchases from BMS at BMS's estimated net selling price of efavirenz in the European Territory. We are responsible for manufacturing, product distribution, inventory management and warehousing. Through our local subsidiaries, we have primary responsibility for order fulfillment, collection of receivables, customer relations and handling of sales returns in all the territories where we and BMS promote Atripla. In general, the parties share revenues and out-of-pocket expenses in proportion to the net selling prices of the components of Atripla, Truvada and efavirenz.

Starting in 2012, except for a limited number of activities that will be jointly managed, the parties no longer coordinate detailing and promotional activities in the region. We are responsible for accounting, financial reporting and tax reporting for the collaboration. As of March 31, 2013 and December 31, 2012, efavirenz purchased from BMS at BMS's estimated net selling price of efavirenz in the European Territory is included in inventories on our Consolidated Balance Sheets.

The parties also formed a limited liability company to hold the marketing authorization for Atripla in Europe. We have primary responsibility for regulatory activities. In the major market countries, both parties have agreed to independently continue to use commercially reasonable efforts to promote Atripla.

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Long-Term Obligations Long-Term Obligations (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Long-term Debt, Unclassified [Abstract]
Debt Principal Repayment, Conversion	$ 97,100,000
Debt Repayment, Conversion Spread	100,800,000
Proceeds from Convertible Note Hedges	100,771,000	0
Repayment of Credit Facility	$ 150,000,000

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Inventories

3 Months Ended

Mar. 31, 2013

Inventory Disclosure [Abstract]

Inventories

INVENTORIES

Inventories are summarized as follows (in thousands):

	March 31, 2013		December 31, 2012
Raw materials	$	693,139	$	826,545
Work in process	529,157		358,525
Finished goods	577,322		559,912
Total	$	1,799,618	$	1,744,982

As of March 31, 2013 and December 31, 2012, the joint ventures formed by Gilead and BMS (See Note 8), which are included in our Consolidated Financial Statements, held $1.27 billion and $1.26 billion in inventory, respectively, of efavirenz active pharmaceutical ingredient which was purchased from BMS at BMS's estimated net selling price of efavirenz.

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Intangible Assets and Goodwill

3 Months Ended

Mar. 31, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets Disclosure [Text Block]

INTANGIBLE ASSETS AND GOODWILL

Intangible Assets

The following table summarizes the carrying amount of our intangible assets (in thousands):

	March 31, 2013		December 31, 2012
Indefinite-lived intangible assets	$	11,348,900	$	10,986,200
Finite-lived intangible assets	728,648		750,193
Total intangible assets	$	12,077,548	$	11,736,393

Indefinite-Lived Intangible Assets

Our indefinite-lived intangible assets consisted primarily of the purchased IPR&D from our acquisition of Pharmasset, Inc. (Pharmasset) in January 2012. We completed our acquisition of YM in February 2013. Of the total $487.6 million preliminary fair value of acquired assets and assumed liabilities, we attributed approximately $362.7 million to IPR&D related to momelotinib on our Consolidated Balance Sheet. The following table summarizes our indefinite-lived intangible assets (in thousands):

	March 31, 2013		December 31, 2012
Indefinite-lived intangible asset - Sofosbuvir	$	10,720,000	$	10,720,000
Indefinite-lived intangible asset - Momelotinib (formerly CYT387)	362,700		—
Indefinite-lived intangible assets - Other	266,200		266,200
Total	$	11,348,900	$	10,986,200

Finite-Lived Intangible Assets

The following table summarizes our finite-lived intangible assets (in thousands):

	March 31, 2013				December 31, 2012
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Intangible asset - Ranexa	$	688,400	$	147,552	$	688,400	$	133,119
Intangible asset - Lexiscan	262,800		101,902		262,800		95,466
Other	42,995		16,093		42,995		15,417
Total	$	994,195	$	265,547	$	994,195	$	244,002

Amortization expense related to finite-lived intangible assets included in cost of goods sold in our Consolidated Statement of Income totaled $21.5 million and $15.8 million for the three months ended March 31, 2013 and 2012, respectively. The weighted-average amortization period for these intangible assets is approximately 11 years. As of March 31, 2013, the estimated future amortization expense associated with our intangible assets for the remaining nine months of 2013 and each of the five succeeding fiscal years is as follows (in thousands):

Fiscal Year	Amount
2013 (remaining nine months)	$	64,636
2014	92,441
2015	97,673
2016	107,312
2017	116,137
2018	124,561
Total	$	602,760

Goodwill

Upon completing the acquisition of YM in February 2013, we preliminarily attributed $127.2 million to goodwill on our Consolidated Balance Sheet. The following table summarizes the changes in the carrying amount of goodwill (in thousands):

Balance at December 31, 2012	$	1,060,919
Goodwill resulting from the acquisition of YM	127,238
Balance at March 31, 2013	$	1,188,157

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Long-Term Obligations

3 Months Ended

Mar. 31, 2013

Long-term Debt, Unclassified [Abstract]

Long-Term Obligations [Text Block]

LONG-TERM OBLIGATIONS

Financing Arrangements

The following table summarizes the carrying amount of our borrowings under various financing arrangements (in thousands):

Type of Borrowing	Description	Issue Date	Due Date	Interest Rate	March 31, 2013		December 31, 2012
Convertible Senior	May 2013 Notes	April 2006	May 2013	0.625%	$	342,759	$	419,433
Convertible Senior	May 2014 Notes	July 2010	May 2014	1.00%	1,211,072		1,210,213
Convertible Senior	May 2016 Notes	July 2010	May 2016	1.625%	1,156,632		1,157,692
Senior Unsecured	April 2021 Notes	March 2011	April 2021	4.50%	993,138		992,923
Senior Unsecured	December 2014 Notes	December 2011	December 2014	2.40%	749,473		749,394
Senior Unsecured	December 2016 Notes	December 2011	December 2016	3.05%	699,152		699,095
Senior Unsecured	December 2021 Notes	December 2011	December 2021	4.40%	1,247,501		1,247,428
Senior Unsecured	December 2041 Notes	December 2011	December 2041	5.65%	997,828		997,810
Credit Facility	Five-Year Revolver	January 2012	January 2017	Variable	600,000		750,000
Total debt, net					$	7,997,555	$	8,223,988
Less current portion					942,759		1,169,433
Total long-term debt, net					$	7,054,796	$	7,054,555

Convertible Senior Notes

During the three months ended March 31, 2013, a portion of the Convertible Notes was converted and we repaid $97.1 million of the principal balance. We also paid $100.8 million in cash related to the conversion spread of the notes, which represents the conversion value in excess of the principal amount, and received $100.8 million in cash from our convertible note hedges related to these notes.

Credit Facility

During the first quarter of 2013, we repaid $150.0 million under the Five-Year Revolving Credit Agreement. The Five-Year Revolving Credit Agreement bears interest at either (i) the Eurodollar Rate plus the Applicable Margin or (ii) the Base Rate plus the Applicable Margin, each as defined in the credit agreement. We may reduce the commitments and may prepay the loan in whole or in part at any time without premium or penalty. We are required to comply with certain covenants under the credit agreement and notes indentures and as of March 31, 2013, we were in compliance with all such covenants.

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Stockholders' Equity Stockholders' Equity Narrative (Details) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Stockholders' Equity Attributable to Parent [Abstract]
Stock Repurchased and Retired During Period, Value	$ 82,200,000
Stock Repurchased and Retired During Period, Shares	2.1
Stock Repurchase Program, Authorized Amount	$ 5,000,000,000

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Segment information Schedule of revenue by major customers (Details)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cardinal Health, Inc. [Member]
Revenue, Major Customer [Line Items]
Percentage of Revenues	19.00%	20.00%
McKesson Corp. [Member]
Revenue, Major Customer [Line Items]
Percentage of Revenues	14.00%	16.00%
AmerisourceBergen Corp. [Member]
Revenue, Major Customer [Line Items]
Percentage of Revenues	11.00%	11.00%

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Stockholders' Equity Schedule of Accumulated Comprehensive Income (loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ (45,615)
Other Comprehensive Income (Loss) Before Reclassifications	66,889
Amounts Reclassified From Accumulated Other Comprehensive Income	(468)
Net Current Period Other Comprehensive Income (Loss)	66,421	(24,609)
Ending Balance	20,806
Foreign Curency Items [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	30,084
Other Comprehensive Income (Loss) Before Reclassifications	(8,956)
Amounts Reclassified From Accumulated Other Comprehensive Income	0
Net Current Period Other Comprehensive Income (Loss)	(8,956)
Ending Balance	21,128
Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(24,002)
Other Comprehensive Income (Loss) Before Reclassifications	1,785
Amounts Reclassified From Accumulated Other Comprehensive Income	(17)
Net Current Period Other Comprehensive Income (Loss)	1,768
Ending Balance	(22,234)
Unrealized Gains and Losses on Cash Flow Hedges [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(51,697)
Other Comprehensive Income (Loss) Before Reclassifications	74,060
Amounts Reclassified From Accumulated Other Comprehensive Income	(451)
Net Current Period Other Comprehensive Income (Loss)	73,609
Ending Balance	$ 21,912

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Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Summary Of Significant Accounting Policies [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1.3	21.8
Total Southern European Accounts Receivable	$ 849.6
Total Southern European Accounts Receivable Greater Than 120 Days Past Due	348.5
Total Southern European Accounts Receivable Greater Than 365 Days Past Due	$ 114.1
Convertible Senior Notes Due In May 2013 [Member]
Summary Of Significant Accounting Policies [Line Items]
Debt Instrument, Convertible, Conversion Price (usd per share)	$ 19.05
Class of Warrant or Right, Exercise Price of Warrants or Rights (usd per share)	26.95
Convertible Senior Notes Due In May 2014 [Member]
Summary Of Significant Accounting Policies [Line Items]
Debt Instrument, Convertible, Conversion Price (usd per share)	$ 22.54
Class of Warrant or Right, Exercise Price of Warrants or Rights (usd per share)	28.38
Convertible Senior Notes Due In May 2016 [Member]
Summary Of Significant Accounting Policies [Line Items]
Debt Instrument, Convertible, Conversion Price (usd per share)	$ 22.71
Class of Warrant or Right, Exercise Price of Warrants or Rights (usd per share)	30.05

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Inventories Inventories (Narrative) (Details) (USD $) In Billions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Inventory Disclosure [Abstract]
Portion of Inventory Related to Efavirenz	$ 1.27	$ 1.26

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Income Taxes

3 Months Ended

Mar. 31, 2013

Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]

Income Tax Disclosure [Text Block]

INCOME TAXES

Our income tax rate of 23.7% for the three months ended March 31, 2013 differed from the U.S. federal statutory rate of 35% due primarily to the retroactive extension of the 2012 federal research tax credit in January 2013 and certain operating earnings from non-U.S. subsidiaries that are considered indefinitely reinvested, partially offset by state taxes and our portion of the non-deductible pharmaceutical excise tax. We do not provide for U.S. income taxes on undistributed earnings of our foreign operations that are intended to be permanently reinvested.

In January 2013, the U.S. Congress passed the American Taxpayer Relief Act of 2012 which retroactively reinstated the federal research tax credit for 2012 and 2013. As a result, our income tax provision for the first quarter of 2013 included a discrete tax benefit related to the federal research tax credit for 2012.

We file federal, state and foreign income tax returns in many jurisdictions in the United States and abroad. For federal income tax purposes, the statute of limitations is open for 2008 and onwards. For certain acquired entities, the statute of limitations is open for all years from inception due to our utilization of their net operating losses and credits carried over from prior years. For California income tax purposes, the statute of limitations is open for 2008 and onwards.

Our income tax returns are audited by federal, state and foreign tax authorities. We are currently under examination by the Internal Revenue Service (IRS) for the 2008 and 2009 tax years and by various state and foreign jurisdictions. There are differing interpretations of tax laws and regulations, and as a result, significant disputes may arise with these tax authorities involving issues of the timing and amount of deductions and allocations of income among various tax jurisdictions. We periodically evaluate our exposures associated with our tax filing positions.

As of March 31, 2013, we believe that it is reasonably possible that our unrecognized tax benefits will decrease by approximately$18 million in the next 12 months as we expect to have clarification from the IRS and other tax authorities regarding some of our uncertain tax positions. With respect to the remaining unrecognized tax benefits, we are currently unable to make a reasonable estimate as to the period of cash settlement, if any, with the respective tax authorities.

We record liabilities related to uncertain tax positions in accordance with the income tax guidance which clarifies the accounting for uncertainty in income taxes recognized in an enterprise’s financial statements by prescribing a minimum recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. We do not believe any of our uncertain tax positions will have a material adverse effect on our Consolidated Financial Statements, although an adverse resolution of one or more of these uncertain tax positions in any period could have a material impact on the results of operations for that period.

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Derivative Financial Instruments Derivative Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2013

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Fair Values of Derivative Instruments on Consolidated Balance Sheets

The following table summarizes the location and fair values of derivative instruments on our Consolidated Balance Sheets (in thousands):

	March 31, 2013
	Asset Derivatives			Liability Derivatives
	Classification	Fair Value		Classification	Fair Value
Derivatives designated as hedges:
Foreign currency exchange contracts	Other current assets	$	33,048	Other accrued liabilities	$	17,915
Foreign currency exchange contracts	Other long-term assets	9,697		Other long-term obligations	106
Total derivatives designated as hedges		42,745			18,021
Derivatives not designated as hedges:
Foreign currency exchange contracts	Other current assets	437		Other accrued liabilities	650
Total derivatives not designated as hedges		437			650
Total derivatives		$	43,182		$	18,671

	December 31, 2012
	Asset Derivatives			Liability Derivatives
	Classification	Fair Value		Classification	Fair Value
Derivatives designated as hedges:
Foreign currency exchange contracts	Other current assets	$	14,556	Other accrued liabilities	$	54,597
Foreign currency exchange contracts	Other long-term assets	142		Other long-term obligations	10,630
Total derivatives designated as hedges		14,698			65,227
Derivatives not designated as hedges:
Foreign currency exchange contracts	Other current assets	125		Other accrued liabilities	21
Total derivatives not designated as hedges		125			21
Total derivatives		$	14,823		$	65,248

Summary of the Effect of Foreign Currency Exchange Contracts on Consolidated Statements of Income

The following table summarizes the effect of our foreign currency exchange contracts on our Consolidated Statements of Income (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Derivatives designated as hedges:
Net gains (losses) recognized in OCI (effective portion)	$	70,860		$	(48,886	)
Net gains reclassified from accumulated OCI into product sales (effective portion)	$	462		$	11,227
Losses recognized in other income (expense), net (ineffective portion and amounts excluded from effectiveness testing)	$	(2,132	)	$	(3,212	)
Derivatives not designated as hedges:
Net gains (losses) recognized in other income (expense), net	$	32,620		$	(27,174	)

Derivatives Netting Tabular Disclosure [Table Text Block]

The following table summarizes the potential effect of offsetting derivatives by type of financial instrument on our Consolidated Balance Sheets (in thousands):

March 31, 2013
Offsetting of Derivative Assets/Liabilities
									Gross Amounts Not Offset in the Consolidated Balance Sheet
Description	Gross Amounts of Recognized Assets/Liabilities			Gross Amounts Offset in the Consolidated Balance Sheet		Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheet			Derivative Financial Instruments			Cash Collateral Received/Pledged		Net Amount (Legal Offset)
Derivative assets	$	43,182		$	—	$	43,182		$	(18,515	)	$	—	$	24,667
Derivative liabilities	(18,671		)	—		(18,671		)	18,515			—		(156		)

December 31, 2012
Offsetting of Derivative Assets/Liabilities
									Gross Amounts Not Offset in the Consolidated Balance Sheet
Description	Gross Amounts of Recognized Assets/Liabilities			Gross Amounts Offset in the Consolidated Balance Sheet		Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheet			Derivative Financial Instruments			Cash Collateral Received/Pledged		Net Amount (Legal Offset)
Derivative assets	$	14,823		$	—	$	14,823		$	(9,644	)	$	—	$	5,179
Derivative liabilities	(65,248		)	—		(65,248		)	9,644			—		(55,604		)

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Acquisition Acquisitions Narrative (Details) (USD $) In Millions, unless otherwise specified	Feb. 08, 2013
Business Combinations [Abstract]
Fair Value of Acquired Assets and Assumed Liabilities	$ 487.6
Acquired Indefinite-Lived Intangible Asset	362.7
Goodwill	127.2
Deferred Tax Liabilities	108.8
Cash Acquired	$ 108.9

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Available-for-Sale Securities Summary of Available-for-Sale Securities by Contractual Maturity (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investments, Debt and Equity Securities [Abstract]
Less than 1 Year, Amortized Cost	$ 1,711,889
Greater than 1 Year but Less than 5 Years, Amortized Cost	661,969
Greater than 5 Years but Less than 10 Years, Amortized Cost	9,437
Greater than 10 Years, Amortized Cost	14,750
Total Amortized Cost	2,398,045
Less than 1 Year, Fair Value	1,711,957
Greater than 1 Year but Less than 5 Years, Fair Value	664,058
Greater than 5 Years but Less than 10 Years, Fair Value	9,460
Greater than 10 Years, Fair Value	14,736
Estimated Fair Value	$ 2,400,211	$ 2,194,748

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Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net Income	$ 717,710	$ 437,531
Other Comprehensive Income [Abstract]
Net Foreign Currency Translation Gain (Loss), net of tax	(8,956)	4,897
Available-for-sale Securities [Abstract]
Net Unrealized Gain (Loss), Net of Tax Impact of $(1,016) and $266	1,785	(463)
Reclassifications to Net Income, Net of Tax Impact of $(9) and $(519)	(17)	30,600
Net Change	1,768	30,137
Cash Flow Hedges [Abstract]
Net Unrealized Gain (Loss), Net of Tax Impact of $(1,849), $1,802	74,060	(48,816)
Reclassifications to Net Income, Net of Tax Impact of $(11) and $(400)	(451)	(10,827)
Net Change	73,609	(59,643)
Other Comprehensive Income (Loss)	66,421	(24,609)
Comprehensive Income	784,131	412,922
Comprehensive Loss Attributable to Noncontrolling Interest	4,476	4,425
Comprehensive Income Attributable to Gilead	$ 788,607	$ 417,347

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Available-for-Sale Securities

3 Months Ended

Mar. 31, 2013

Investments, Debt and Equity Securities [Abstract]

Available-for-Sale Securities Disclosure [Text Block]

AVAILABLE-FOR-SALE SECURITIES

The following table is a summary of available-for-sale debt securities recorded in cash and cash equivalents or marketable securities in our Consolidated Balance Sheets (in thousands):

	March 31, 2013									December 31, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Debt securities:
U.S. treasury securities	$	95,661	$	194	$	—		$	95,855	$	81,752	$	151	$	—		$	81,903
Money market funds	1,633,153		—		—			1,633,153		1,416,356		—		—			1,416,356
U.S. government agencies securities	217,680		358		—			218,038		248,595		386		(29		)	248,952
Municipal debt securities	12,049		66		—			12,115		12,062		33		(7		)	12,088
Corporate debt securities	353,468		1,630		(35		)	355,063		351,309		1,492		(84		)	352,717
Residential mortgage and asset-backed securities	86,034		96		(143		)	85,987		82,717		156		(141		)	82,732
Total	$	2,398,045	$	2,344	$	(178	)	$	2,400,211	$	2,192,791	$	2,218	$	(261	)	$	2,194,748

Estimated fair values of available-for-sale securities are generally based on prices obtained from commercial pricing services. The following table summarizes the classification of the available-for-sale debt securities on our Consolidated Balance Sheets (in thousands):

	March 31, 2013		December 31, 2012
Cash and cash equivalents	$	1,633,153	$	1,416,356
Short-term marketable securities	78,804		58,556
Long-term marketable securities	688,254		719,836
Total	$	2,400,211	$	2,194,748

Cash and cash equivalents in the table above exclude cash of $230.8 million and $387.3 million as of March 31, 2013 and December 31, 2012, respectively.

The following table summarizes our portfolio of available-for-sale debt securities by contractual maturity (in thousands):

	March 31, 2013
	Amortized Cost		Fair Value
Less than one year	$	1,711,889	$	1,711,957
Greater than one year but less than five years	661,969		664,058
Greater than five years but less than ten years	9,437		9,460
Greater than ten years	14,750		14,736
Total	$	2,398,045	$	2,400,211

The following table summarizes the gross realized gains and losses related to sales of marketable securities (in thousands):

	Three Months Ended
	March 31,
	2013			2012
Gross realized gains on sales	$	182		$	10,015
Gross realized losses on sales	$	(156	)	$	(40,096	)

The cost of securities sold was determined based on the specific identification method.

The following table summarizes our available-for-sale debt securities that were in a continuous unrealized loss position, but were not deemed to be other-than-temporarily impaired (in thousands):

	Less Than 12 Months					12 Months or Greater				Total
	Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value
March 31, 2013
Debt securities:
U.S. government agencies securities	$	—		$	—	$	—	$	—	$	—		$	—
Municipal debt securities	—			—		—		—		—			—
Corporate debt securities	(35		)	47,567		—		—		(35		)	47,567
Residential mortgage and asset-backed securities	(143		)	47,748		—		—		(143		)	47,748
Total	$	(178	)	$	95,315	$	—	$	—	$	(178	)	$	95,315
December 31, 2012
Debt securities:
U.S. government agencies securities	$	(29	)	$	26,306	$	—	$	—	$	(29	)	$	26,306
Municipal debt securities	(7		)	3,993		—		—		(7		)	3,993
Corporate debt securities	(84		)	72,722		—		—		(84		)	72,722
Residential mortgage and asset-backed securities	(141		)	36,415		—		—		(141		)	36,415
Total	$	(261	)	$	139,436	$	—	$	—	$	(261	)	$	139,436

As of March 31, 2013 and December 31, 2012, we held a total of 37 and 47 securities, respectively, that were in an unrealized loss position. Based on our review of these securities, we believe we had no other-than-temporary impairments on these securities as of March 31, 2013 and December 31, 2012 because we do not intend to sell these securities and it is not more likely than not that we will be required to sell these securities before the recovery of their amortized cost basis.

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Collaborative Arrangements Collaborative Arrangements Narrative (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Variable Interest Entity [Line Items]
Variable Interest Entity, Cash and Cash Equivalents	$ 1,863,972,000	$ 1,803,694,000	$ 1,451,942,000	$ 9,883,777,000
Variable Interest Entity, Inventories	1,799,618,000	1,744,982,000
Variable Interest Entity, Accounts Payable	1,356,372,000	1,327,339,000
Variable Interest Entity, Other Accrued Expenses	819,009,000	674,762,000
Variable Interest Entity, Primary Beneficiary [Member] | Bristol-Myers Squibb Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Carrying Amount, Total Assets	2,240,000,000	1,950,000,000
Variable Interest Entity, Cash and Cash Equivalents	147,700,000	191,100,000
Variable Interest Entity, Accounts Receivables	291,700,000	223,700,000
Variable Interest Entity, Inventories	1,740,000,000	1,540,000,000
Variable Interest Entity, Consolidated, Carrying Amount, Total Liabilities	1,610,000,000	1,320,000,000
Variable Interest Entity, Accounts Payable	569,900,000	501,700,000
Variable Interest Entity, Other Accrued Expenses	$ 367,300,000	$ 291,500,000

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Inventories Inventories (Tables)

3 Months Ended

Mar. 31, 2013

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories are summarized as follows (in thousands):

	March 31, 2013		December 31, 2012
Raw materials	$	693,139	$	826,545
Work in process	529,157		358,525
Finished goods	577,322		559,912
Total	$	1,799,618	$	1,744,982

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Fair value measurements Fair value measurements Narrative (Details) (USD $)	3 Months Ended
	Sep. 30, 2012	Mar. 31, 2012	Mar. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proceeds from sale of auction rate securities	$ 37,300,000
Loss on sale of auction rate securities	3,800,000
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, loss included in earnings		40,100,000
Fair value, measurement with unobservable inputs reconciliations, recurring basis, liability value			211,084,000	205,060,000
CGI and Calistoga [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business combination, contingent consideration arrangements, range of outcomes, value, high			254,000,000
Fair value, measurement with unobservable inputs reconciliations, recurring basis, liability value			$ 163,900,000	$ 159,300,000

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Segment information

3 Months Ended

Mar. 31, 2013

Segment Reporting [Abstract]

Segment Reporting Disclosure [Text Block]

SEGMENT INFORMATION

We operate in one business segment, which primarily focuses on the development and commercialization of human therapeutics for life threatening diseases. All products are included in one segment, because the majority of our products have similar economic and other characteristics, including the nature of the products and production processes, type of customers, distribution methods and regulatory environment.

Product sales consist of the following (in thousands):

	Three Months Ended
	March 31,
	2013		2012
Antiviral products:
Atripla	$	877,073	$	887,596
Truvada	700,242		758,263
Viread	210,332		191,693
Complera/Eviplera	148,189		52,180
Stribild	92,148		—
Hepsera	26,423		29,297
Emtriva	6,671		6,777
Total antiviral products	2,061,078		1,925,806
Letairis	118,107		87,288
Ranexa	96,286		83,201
AmBisome	85,275		84,764
Other products	32,822		27,283
Total product sales	$	2,393,568	$	2,208,342

The following table summarizes revenues from each of our customers who individually accounted for 10% or more of our total revenues (as a percentage of total revenues):

	Three Months Ended
	March 31,
	2013		2012
Cardinal Health, Inc.	19	%	20	%
McKesson Corp.	14	%	16	%
AmerisourceBergen Corp.	11	%	11	%