The tables below present information about our assets and liabilities that are regularly measured and carried at fair value and indicate the level within the fair value hierarchy of the valuation techniques we utilized to determine such fair value:


	Fair Value Measurements on a Recurring Basis
	As of September 30, 2022
(In millions)	Total		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents	$	3,191.8	$	—	$	3,191.8	$	—
Marketable debt securities:
Corporate debt securities	1,219.1		—		1,219.1		—
Government securities	702.0		—		702.0		—
Mortgage and other asset backed securities	174.7		—		174.7		—
Marketable equity securities	896.0		896.0		—		—
Other current assets:
Receivable from Samsung BioLogics(1)	790.8		—		—		790.8
Other assets:
Derivative contracts	195.9		—		195.9		—
Plan assets for deferred compensation	32.2		—		32.2		—
Receivable from Samsung BioLogics(1)	402.8		—		—		402.8
Total	$	7,605.3	$	896.0	$	5,515.7	$	1,193.6
Liabilities:
Derivative contracts	$	22.8	$	—	$	22.8	$	—
Contingent consideration obligations	195.4		—		—		195.4
Total	$	218.2	$	—	$	22.8	$	195.4

(1) Represents the fair value of the current and non-current payments due from Samsung BioLogics as a result of the sale of our 49.9% equity interest in Samsung Bioepis to Samsung BioLogics during the second quarter of 2022, for which we elected the fair value option. For additional information on the sale of our equity interest in Samsung Bioepis, please read Note 2, Dispositions, to these condensed consolidated financial statements.


	Fair Value Measurements on a Recurring Basis
	As of December 31, 2021
(In millions)	Total		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents	$	1,632.2	$	—	$	1,632.2	$	—
Marketable debt securities:
Corporate debt securities	1,108.2		—		1,108.2		—
Government securities	1,192.7		—		1,192.7		—
Mortgage and other asset backed securities	132.2		—		132.2		—
Marketable equity securities	1,048.5		181.7		866.8		—
Derivative contracts	80.9		—		80.9		—
Plan assets for deferred compensation	33.4		—		33.4		—
Total	$	5,228.1	$	181.7	$	5,046.4	$	—
Liabilities:
Derivative contracts	$	10.8	$	—	$	10.8	$	—
Contingent consideration obligations	209.1		—		—		209.1
Total	$	219.9	$	—	$	10.8	$	209.1

The fair value of Level 2 instruments classified as cash equivalents and marketable debt securities was determined through third-party pricing services. As of September 30, 2022, we elected to early adopt ASU 2022-03 on a prospective basis, which resulted in removing the impact of contractual sale restrictions from the fair value measurement of our remaining Sage common stock subject to certain holding period restrictions. As of September 30, 2022, our entire investment in the common stock of Sage was classified as a Level 1 measurement. Prior to the adoption of this standard, the fair value of Level 2 instruments classified as marketable equity securities represented a portion of our investment in the common stock of Sage and was valued using an option pricing valuation model. The initial holding period restriction for a portion of our investment in the common stock of Sage expired during the second quarter of 2022 with the remaining holding period restriction set to expire in the fourth quarter of 2022.

Our investments in the common stock of Sangamo Therapeutics, Inc. (Sangamo) and Denali Therapeutics Inc. (Denali) had holding period restrictions that expired during 2022. As of September 30, 2022, the fair values of our investments in Sangamo and Denali common stock were classified as Level 1 measurements. Prior to the expiration of these holding period restrictions the investments were classified as Level 2 measurements.

For additional information on our investments in Sangamo, Denali and Sage common stock, please read Note 18, Collaborative and Other Relationships, to our consolidated financial statements included in our 2021 Form 10-K.

There have been no material impairments of our assets measured and carried at fair value as of September 30, 2022 and December 31, 2021. There have been no significant changes to our valuation techniques as of September 30, 2022 and December 31, 2021.

For a description of our validation procedures related to prices provided by third-party pricing services and our option pricing valuation model, please read Note 1, Summary of Significant Accounting Policies - Fair Value Measurements, to our consolidated financial statements included in our 2021 Form 10-K.

The following table presents quantitative information, as of the dates indicated, about the valuation techniques and significant unobservable inputs used in the valuation of our level 3 financial assets and liabilities measured at fair value on a recurring basis:

Quantitative Information about Level 3 Fair Value Measurements

Fair Value

Weighted Average

(In millions)

September 30, 2022

December 31, 2021

Valuation Technique

Significant
Unobservable Input(s)

Range

September 30, 2022

December 31, 2021

Liabilities:

Contingent consideration obligations

195.4

209.1

Discounted cash flow

Discount rate

4.50%

4.50

1.30

Expected timing of achievement of development milestones

2023 to 2028

—

The weighted average discount rates were calculated based on the relative fair value of our contingent consideration obligations. In addition, we apply various probabilities of technological and regulatory success to the valuation models to estimate the fair values of our contingent consideration obligations, which ranged from 10.9% to certain probability as of September 30, 2022 and December 31, 2021.

In connection with our acquisitions of Convergence and Biogen International Neuroscience GmbH, we agreed to make additional payments based upon the achievement of certain milestone events. The following table provides a roll forward of the fair values of our contingent consideration obligations, which are classified as Level 3 measurements:


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
(In millions)	2022		2021		2022		2021
Fair value, beginning of period	$	197.5	$	226.3	$	209.1	$	259.8
Changes in fair value	(2.1)		(15.6)		(13.7)		(49.1)

Fair value, end of period	$	195.4	$	210.7	$	195.4	$	210.7

As of September 30, 2022 and December 31, 2021, approximately $195.4 million and $209.1 million, respectively, of the fair value of our total contingent consideration obligations was reflected as a component of other long-term liabilities in our condensed consolidated balance sheets with any remaining balances reflected as a component of accrued expense and other. Changes in the fair values of our contingent consideration obligations are recorded in (gain) loss on fair value remeasurement of contingent consideration in our condensed consolidated statements of income.

For the three and nine months ended September 30, 2022, the changes in the fair value of our contingent consideration obligations were primarily due to increases in the discount rates used to revalue these obligations and delays in the expected timing of the achievement of certain remaining developmental milestones related to our vixotrigine programs.

For the three and nine months ended September 30, 2021, the changes in the fair value of our contingent consideration obligations were primarily due to reductions in the probability of technical and regulatory success and delays in the expected timing of the achievement of certain remaining developmental milestones related to our vixotrigine programs.

Due to the short-term nature of certain financial instruments, the carrying value reflected in our condensed consolidated balance sheets for current accounts receivable, due from anti-CD20 therapeutic programs, other current assets, accounts payable and accrued expense and other, approximates fair value.


	As of September 30, 2022				As of December 31, 2021
(In millions)	Fair Value		Carrying Value		Fair Value		Carrying Value

3.625% Senior Notes due September 15, 2022(1)	$	—	$	—	$	1,020.0	$	999.1
4.050% Senior Notes due September 15, 2025	1,697.8		1,744.3		1,895.2		1,742.9
2.250% Senior Notes due May 1, 2030	1,183.0		1,492.7		1,475.9		1,492.0
5.200% Senior Notes due September 15, 2045	997.2		1,100.2		1,463.0		1,099.9
3.150% Senior Notes due May 1, 2050	965.6		1,473.6		1,457.7		1,473.2
3.250% Senior Notes due February 15, 2051	452.8		468.4		692.9		466.0
Total	$	5,296.4	$	6,279.2	$	8,004.7	$	7,273.1

(1) Our 3.625% Senior Notes due September 15, 2022, were redeemed in full in July 2022. For additional information, please read Note 12, Indebtedness, to these condensed consolidated financial statements.

The fair values of each of our series of Senior Notes were determined through market, observable and corroborated sources. The changes in the fair values of our Senior Notes as of September 30, 2022, compared to December 31, 2021, are related to increases in U.S. treasury yields and wider credit spreads used to value our Senior Notes since December 31, 2021. For additional information related to our Senior Notes, please read Note 12, Indebtedness, to our consolidated financial statements included in our 2021 Form 10-K.