We are a provider of sequencing- and array-based solutions, serving customers in the research, clinical and applied markets. Our products are used for applications in the life sciences, oncology, reproductive health, agriculture and other emerging segments. Our customers include leading genomic research centers, academic institutions, government laboratories, and hospitals, as well as pharmaceutical, biotechnology, commercial molecular diagnostic laboratories, and consumer genomics companies.

The consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles and include our accounts, our wholly-owned subsidiaries, majority-owned or controlled companies, and variable interest entities for which we are the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to the current period presentation.

We evaluate our ownership, contractual and other interests in entities that are not wholly-owned to determine if these entities are VIEs, and, if so, whether we are the primary beneficiary of the VIE. In determining whether we are the primary beneficiary of a VIE and therefore required to consolidate the VIE, we apply a qualitative approach that determines whether we have both (1) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (2) the obligation to absorb losses of, or the rights to receive benefits from, the VIE that could potentially be significant to that VIE. We continuously perform this assessment, as changes to existing relationships or future transactions may result in the consolidation or deconsolidation of a VIE. See note “3. Investments and Fair Value Measurements” for further details.

The preparation of the consolidated financial statements requires that management make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses, and related disclosures of contingent assets and liabilities. Though the impact of the COVID-19 pandemic to our business and operating results presents additional uncertainty, we continue to use the best information available to inform our critical accounting estimates. Actual results could differ from those estimates.

Our fiscal year is the 52 or 53 weeks ending the Sunday closest to December 31, with quarters of 13 or 14 weeks ending the Sunday closest to March 31, June 30, September 30, and December 31. References to 2020, 2019, and 2018 refer to fiscal years ended January 3, 2021, December 29, 2019, and December 30, 2018, respectively. Fiscal year 2020 was 53 weeks, and fiscal years 2019 and 2018 were both 52 weeks.

We operate in markets that are highly competitive and rapidly changing. Significant technological changes, shifting customer needs, the emergence of competitive products or services with new capabilities, and other factors could negatively impact our operating results. A portion of our customers consist of university and research institutions that management believes are, to some degree, directly or indirectly supported by the United States Government. A significant change in current research funding, particularly with respect to the U.S. National Institutes of Health, could have an adverse impact on future revenues and results of operations.

International sales entail a variety of risks, including currency exchange fluctuations, longer payment cycles, and greater difficulty in accounts receivable collection. We are also subject to general geopolitical risks, such as political, social and economic instability, and changes in diplomatic and trade relations. The risks of international sales are mitigated in part by the extent to which sales are geographically distributed. Shipments to customers outside the United States comprised 49%, 48%, and 47% of total revenue in 2020, 2019, and 2018, respectively. Customers outside the United States represented 56% and 53% of our gross trade accounts receivable balance as of January 3, 2021 and December 29, 2019, respectively.

We are also subject to risks related to our financial instruments, including cash and cash equivalents, investments, and accounts receivable. Most of our cash and cash equivalents as of January 3, 2021 were deposited with U.S. financial institutions, either domestically or with their foreign branches. Our investment policy restricts the amount of credit exposure to any one issuer to 5% of the portfolio or 5% of the total issue size outstanding at the time of purchase and to any one industry sector, as defined by Clearwater Analytics (Industry Sector Report), to 30% of the portfolio at the time of purchase. There is no limit to the percentage of the portfolio that may be maintained in debt securities, U.S. government-sponsored entities, U.S. Treasury securities, and money market funds. Historically, we have not experienced significant credit losses from financial instruments.

We report segment information based on the management approach. This approach designates the internal reporting used by the Chief Operating Decision Maker (CODM) for making decisions and assessing performance as the source of our reportable segments. The CODM allocates resources and assesses the performance of each operating segment using information about its revenue and income (loss) from operations. Management evaluates the performance of our reportable segments based upon income (loss) from operations. We do not allocate expenses between segments.

In May 2020, the SEC issued Final Rule Release No. 33-10786, Amendments to Financial Disclosures about Acquired and Disposed Businesses, which amends the disclosure requirements applicable to acquisitions and dispositions of businesses, including the required pro forma financial information. The amendments are effective for us beginning January 1, 2021, with early compliance permitted. Among other changes, the final amendments revised the investment and income tests used to determine whether a business acquisition is significant and reduced the filing requirements for financial statements and pro forma financial information of a significant acquired business to cover a maximum of two years. We elected to adopt the amendments in 2020 in connection with our pending acquisition of GRAIL, which is further described in note “4. Intangible Assets, Goodwill, and Acquisitions”.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments, which amends the impairment model by requiring entities to use a forward-looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables and available-for-sale debt securities. We adopted the standard on its effective date in the first quarter of 2020 using a modified retrospective approach. The cumulative effect of applying the new credit loss standard was not material and, therefore, did not result in an adjustment to retained earnings. There was no material difference to the consolidated financial statements in 2020 due to the adoption of ASU 2016-13.

In accordance with ASU 2016-13, we no longer evaluate whether our available-for-sale debt securities in an unrealized loss position are other than temporarily impaired. Instead, we assess whether such unrealized loss positions are credit-related. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded in interest income through an allowance account. Unrealized gains and losses that are not credit-related are included in accumulated other comprehensive income (loss). We estimate our allowance for credit losses on our trade receivables as described in our Accounts Receivable policy, below.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which requires lessees to recognize most leases on the balance sheet as lease liabilities with corresponding right-of-use assets and to disclose key information about leasing arrangements. We adopted Topic 842 on its effective date in the first quarter of 2019 using a modified retrospective approach by recognizing a cumulative-effect adjustment to retained earnings as of December 31, 2018. We elected the available package of practical expedients upon adoption, which allowed us to carry forward our historical assessment of whether existing agreements contained a lease and the classification of our existing operating leases.


	December 31, 2018
In millions	Pre-adoption		Adoption Impact		Post-adoption
ASSETS
Prepaid expenses and other current assets	$	78	$	(8)	$	70
Property and equipment, net	1,075		(241)		834
Operating lease right-of-use assets	—		579		579
Deferred tax assets, net	70		6		76
Total assets	$	1,223	$	336	$	1,559
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accrued liabilities	$	513	$	36	$	549

Operating lease liabilities	—		722		722
Long-term debt	1,107		(269)		838
Other long-term liabilities	359		(135)		224
Retained earnings	3,083		(18)		3,065
Total liabilities and stockholders’ equity	$	5,062	$	336	$	5,398

The adoption impact summarized above was primarily due to the recognition of operating lease liabilities with corresponding right-of-use assets based on the present value of our remaining minimum lease payments, and the derecognition of existing fixed assets and financing obligations related to build-to-suit leasing arrangements that, under Topic 840, did not qualify for sale-leaseback accounting. The difference between these amounts, net of deferred tax, was recorded as a cumulative-effect adjustment to retained earnings.

In August 2020, the FASB issued ASU 2020-06, Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity’s Own Equity (Subtopic 815-40). The new standard reduces the number of accounting models for convertible debt instruments, amends the accounting for certain contracts in an

entity’s own equity, and modifies how certain convertible instruments and contracts that may be settled in cash or shares impact the calculation of diluted EPS. The standard is effective for us beginning in the first quarter of 2022, with early adoption permitted in Q1 2021. We do not expect to early adopt the new standard. We are currently evaluating the impact of ASU 2020-06 on the consolidated financial statements.

Our revenue is generated primarily from the sale of products and services. Product revenue primarily consists of sales of instruments and consumables used in genetic analysis. Service and other revenue primarily consists of revenue generated from genotyping and sequencing services, instrument service contracts, and development and licensing agreements.

We recognize revenue when control of our products and services is transferred to our customers in an amount that reflects the consideration we expect to receive from our customers in exchange for those products and services. This process involves identifying the contract with a customer, determining the performance obligations in the contract, determining the contract price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when the performance obligations have been satisfied. Revenue recognition for contracts with multiple deliverables is based on the separate satisfaction of each distinct performance obligation within the contract. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. We consider a performance obligation satisfied once we have transferred control of a good or service to the customer, meaning the customer has the ability to use and obtain the benefit of the good or service. The contract price is allocated to each performance obligation in proportion to its standalone selling price. We determine our best estimate of standalone selling price using average selling prices over a rolling 12-month period coupled with an assessment of current market conditions. If the product or service has no history of sales or if the sales volume is not sufficient, we rely upon prices set by management, adjusted for applicable discounts.

Revenue from product sales is recognized generally upon delivery to the end customer, which is when control of the product is deemed to be transferred. Invoicing typically occurs upon shipment and payment is typically due within 60 days from invoice. In instances where right of payment or transfer of title is contingent upon the customer’s acceptance of the product, revenue is deferred until all acceptance criteria have been met. Revenue from genotyping and sequencing services is recognized when earned, which is generally at the time the genotyping or sequencing analysis data is made available to the customer. Revenue from instrument service contracts is recognized as the services are rendered, typically evenly over the contract term. Revenue from development and licensing agreements generally includes upfront and periodic licensing fees, contract research and development services, or payments for development and regulatory milestones. Revenue for these agreements is recognized when each distinct performance obligation is satisfied.

Basic earnings per share attributable to Illumina stockholders is computed based on the weighted average number of common shares outstanding during the period. Diluted earnings per share attributable to Illumina stockholders is computed based on the sum of the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Up to April 25, 2019, the date of the Helix deconsolidation, per-share losses of Helix were included in the consolidated basic and diluted earnings per share computations based on our share of the entities’ securities.

Potentially dilutive common shares consist of shares issuable under convertible senior notes and equity awards. Convertible senior notes have a dilutive impact when the average market price of our common stock exceeds the applicable conversion price of the respective notes. Potentially dilutive common shares from equity awards are

The fair value of assets and liabilities are based on the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value maximize the use of observable inputs and minimize the use of unobservable inputs. We use a fair value hierarchy with three levels of inputs, of which the first two are considered observable and the last unobservable, to measure fair value:

•Level 2 — Inputs, other than Level 1, that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices 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 assets or liabilities.

We hold debt securities in U.S. government-sponsored entities, corporate debt securities, and U.S. Treasury securities. We have the ability, if necessary, to liquidate any of our short-term debt securities to meet our liquidity needs in the next 12 months. Accordingly, those investments with contractual maturities greater than one year from the date of purchase are classified as short-term investments on the accompanying consolidated balance sheets. We classify short-term debt investments as available-for-sale at the time of purchase and evaluate such classification as of each balance sheet date. All short-term debt investments are recorded at estimated fair value. We evaluate our available-for-sale debt securities in an unrealized loss position to assess whether such unrealized loss positions are credit-related. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded in interest income through an allowance account. Unrealized gains and losses that are not credit-related are included in accumulated other comprehensive income (loss), a component of stockholders’ equity. Realized gains and losses are determined based on the specific identification method and are recorded in interest income in the consolidated statements of income.

We have strategic investments in privately-held companies (non-marketable equity securities) and companies that have completed initial public offerings (marketable equity securities). Our marketable equity securities are measured at fair value. Our non-marketable equity securities without readily determinable market values are initially measured at cost and adjusted to fair value for observable transactions for identical or similar investments of the same issuer or impairment. Equity investments are classified as current or noncurrent based on the nature of the securities and their availability for use in current operations. Unrealized gains and losses for equity investments are recorded in other income, net in the consolidated statements of income.

Trade accounts receivable are recorded at the net invoice value and are not interest-bearing. Receivables are considered past due based on the contractual payment terms. We reserve specific receivables when collectibility is no longer probable. We also reserve a percentage of our trade receivable balance based on collection history and current economic trends that we expect will impact the level of credit losses over the life of our receivables. These reserves are re-evaluated on a regular basis and adjusted, as needed. Once a receivable is deemed to be uncollectible, such balance is charged against the reserve.

Inventory is stated at the lower of cost or net realizable value, on a first-in, first-out basis. Inventory includes raw materials and finished goods that may be used in the research and development process, and such items are expensed as consumed or capitalized as property and equipment and depreciated. Inventory write-downs for slow-moving, excess, and obsolete inventories are estimated based on product life cycles, quality issues, historical experience, and usage forecasts.

Property and equipment are stated at cost, subject to review for impairment, and depreciated over the estimated useful lives of the assets, using the straight-line method. Depreciation of leasehold improvements is recorded over the shorter of the lease term or the estimated useful life of the related assets. Maintenance and repairs are expensed as incurred. When assets are sold, or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and any gain or loss is included in operating expense.

Costs incurred to develop internal-use software during the application development stage are recorded as computer software costs, at cost. Costs incurred in the development of such internal-use software, including external direct costs of materials and services and applicable compensation costs of employees devoted to specific software application development, are capitalized. Cost incurred outside of the application development stage are expensed as incurred.

We lease approximately 2.6 million square feet of office, lab, manufacturing, and distribution facilities under various non-cancellable operating lease agreements (real estate leases). Our real estate leases have remaining lease terms of approximately 1 to 19 years, which represent the non-cancellable periods of the leases and include extension options that we determined are reasonably certain to be exercised. We exclude extension options that are not reasonably certain to be exercised from our lease terms, ranging from approximately 6 months to 20 years. Our lease payments consist primarily of fixed rental payments for the right to use the underlying leased assets over the lease terms as well as payments for common-area-maintenance and administrative services. We often receive customary incentives from our landlords, such as reimbursements for tenant improvements and rent abatement periods, which effectively reduce the total lease payments owed for these leases. Leases are classified as operating or financing at commencement. We do not have any material financing leases.

Operating lease right-of-use assets and liabilities on our consolidated balance sheets represent the present value of our remaining lease payments over the remaining lease terms. We do not allocate lease payments to non-lease components; therefore, fixed payments for common-area-maintenance and administrative services are included in our operating lease right-of-use assets and liabilities. We use our incremental borrowing rate to calculate the present value of our lease payments, as the implicit rates in our leases are not readily determinable. Operating lease costs consist primarily of the fixed lease payments included in our operating lease liabilities and are recorded on a straight-line basis over the lease terms. We sublease certain real estate to third parties and this sublease income is also recorded on a straight-line basis.

Goodwill is reviewed for impairment at least annually during the second quarter, or more frequently if an event occurs indicating the potential for impairment. During the goodwill impairment review, we assess qualitative factors to determine whether it is more likely than not that the fair values of our reporting units are less than the carrying amounts, including goodwill. The qualitative factors include, but are not limited to, macroeconomic conditions, industry and market considerations, and the overall financial performance. If, after assessing the totality of these qualitative factors, we determine that it is not more likely than not that the fair values of our reporting units are less than the carrying amounts, then no additional assessment is deemed necessary. Otherwise, we proceed to compare the estimated fair values of the reporting units with the carrying values, including goodwill. If the carrying amounts of the reporting units exceed the fair values, we record an impairment loss based on the difference. We may also elect to bypass the qualitative assessment in a period and elect to proceed to perform the quantitative goodwill impairment test.

Our identifiable intangible assets are typically comprised of acquired core technologies, licensed technologies, customer relationships, license agreements, and trade names. The cost of identifiable intangible assets with finite lives is generally amortized on a straight-line basis over the assets’ respective estimated useful lives.

We perform regular reviews to determine if any event has occurred that may indicate that intangible assets with finite useful lives and other long-lived assets are potentially impaired. If indicators of impairment exist, an impairment test is performed to assess the recoverability of the affected assets by determining whether the carrying amount of such assets exceeds the undiscounted expected future cash flows. If the affected assets are not recoverable, we estimate the fair value of the assets and record an impairment loss if the carrying value of the assets exceeds the fair value. Factors that may indicate potential impairment include a significant decline in our stock price and market capitalization compared to the net book value, significant changes in the ability of a particular asset to generate positive cash flows for our strategic business objectives, and the pattern of utilization of a particular asset.

We are exposed to foreign exchange rate risks in the normal course of business and use derivative financial instruments to partially offset this exposure. We do not use derivative financial instruments for speculative or trading purposes. All foreign exchange contracts are carried at fair value in other current assets or accrued liabilities on the consolidated balance sheet.

We use foreign exchange forward contracts to manage foreign currency risks related to monetary assets and liabilities denominated in currencies other than the U.S. dollar. These derivative financial instruments have terms of one month or less and are not designated as hedging instruments. Changes in fair value of these derivatives are recognized in other income, net, along with the re-measurement gain or loss on the foreign currency denominated assets or liabilities. As of January 3, 2021, we had foreign exchange forward contracts in place to hedge exposures to monetary assets and liabilities denominated in the euro, Japanese yen, Australian dollar, Canadian dollar, Singapore dollar, Chinese Yuan Renminbi, and British pound. As of January 3, 2021 and December 29, 2019, the total notional amounts of outstanding forward contracts in place for these foreign currency purchases was $405 million and $252 million, respectively.

We also use foreign currency forward contracts to hedge portions of our foreign currency exposure associated with forecasted revenue transactions. These derivative financial instruments have terms of twelve months or less and are designated as cash flow hedges. Changes in fair value of our cash flow hedges are recorded as a component of accumulated other comprehensive income and are reclassified to revenue in the same period the underlying hedged transactions are recorded. We regularly review the effectiveness of our cash flow hedges and consider them to be ineffective if it becomes probable that the forecasted transactions will not occur in the identified period. Changes in fair value of the ineffective portions of our cash flow hedges, if any, will be recognized in other income, net. As of January 3, 2021, we had foreign currency forward contracts in place to hedge exposures associated with forecasted revenue transactions denominated in the euro, Japanese yen, Australian dollar, and Canadian dollar. As of January 3, 2021, the total notional amounts of outstanding cash flow hedge contracts in place for these foreign currency purchases was $305 million. There were no outstanding cash flow hedge contracts in place as of December 29, 2019.

We generally provide a one-year warranty on instruments. Additionally, we provide a warranty on consumables through the expiration date, which generally ranges from six to twelve months after the manufacture date. At the time revenue is recognized, an accrual is established for estimated warranty expenses based on historical experience as well as anticipated product performance. We periodically review the warranty reserve for adequacy and adjust the warranty accrual, if necessary, based on actual experience and estimated costs to be incurred. Warranty expense is recorded as a component of cost of product revenue.

Restricted stock units (RSU) and performance stock units (PSU) are both considered restricted stock. The fair value of restricted stock is determined by the closing market price of our common stock on the date of grant. Share-based compensation expense is recognized based on the fair value on a straight-line basis over the requisite service periods of the awards. PSU represents a right to receive a certain number of shares of common stock based on the achievement of corporate performance goals and continued employment during the vesting period. At each reporting period, we reassess the probability of the achievement of such corporate performance goals and any increase or decrease in share-based compensation expense resulting from an adjustment in the estimated shares to be released is treated as a cumulative catch-up in the period of adjustment.

volatility is determined by equally weighing the historical and implied volatility of our common stock. The historical volatility is generally commensurate with the estimated expected term, adjusted for the impact of unusual fluctuations and other relevant factors. The implied volatility is calculated from the implied market volatility of exchange-traded call options on our common stock. The expected term is based on historical forfeiture experience and the terms and conditions of the ESPP. The expected dividend yield is determined to be 0% given that we have never declared or paid cash dividends on our common stock and do not anticipate paying such cash dividends. The risk-free interest rate is based upon U.S. Treasury securities with remaining terms similar to the expected term of the share-based awards.

The provision for income taxes is computed using the asset and liability method, under which deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities, and for the expected future tax benefit to be derived from tax loss and credit carryforwards. Deferred tax assets and liabilities are determined using the enacted tax rates in effect for the years in which those tax assets are expected to be realized. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in the provision for income taxes in the period that includes the enactment date.

Deferred tax assets are regularly assessed to determine the likelihood they will be recovered from future taxable income. A valuation allowance is established when we believe it is more likely than not the future realization of all or some of a deferred tax asset will not be achieved. In evaluating the ability to recover deferred tax assets within the jurisdiction which they arise, we consider all available positive and negative evidence. Factors reviewed include the cumulative pre-tax book income for the past three years, scheduled reversals of deferred tax liabilities, history of earnings and reliable forecasting, projections of pre-tax book income over the foreseeable future, and the impact of any feasible and prudent tax planning strategies.