ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES | ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Organization Gilead Sciences, Inc. (including its consolidated subsidiaries, referred to as “Gilead,” the “company,” “we,” “our” or “us”) is a biopharmaceutical company that has pursued and achieved breakthroughs in medicine for more than three decades, with the goal of creating a healthier world for all people. We are committed to advancing innovative medicines to prevent and treat life-threatening diseases, including HIV, viral hepatitis, coronavirus disease 2019 (“COVID-19”) and cancer. We operate in more than 35 countries worldwide, with headquarters in Foster City, California. Our portfolio of marketed products includes AmBisome ® , Atripla ® , Biktarvy ® , Cayston ® , Complera ® , Descovy ® , Descovy for PrEP ® , Emtriva ® , Epclusa ® , Eviplera ® , Genvoya ® , Harvoni ® , Hepcludex ® , Hepsera ® , Jyseleca ® , Letairis ® , Odefsey ® , Sovaldi ® , Stribild ® , Sunlenca ® , Tecartus ® , Trodelvy ® , Truvada ® , Truvada for PrEP ® , Tybost ® , Veklury ® , Vemlidy ® , Viread ® , Vosevi ® , Yescarta ® and Zydelig ® . The approval status of Hepcludex and Jyseleca vary worldwide, and Hepcludex and Jyseleca are not approved in the U.S. We also sell and distribute authorized generic versions of Epclusa and Harvoni in the U.S. through our separate subsidiary, Asegua Therapeutics, LLC. In addition, we sell and distribute certain products through our corporate partners under collaborative agreements. See Note 2. Revenues for a summary of disaggregated revenues by product and geographic region. We have one operating segment which primarily focuses on the discovery, development and commercialization of innovative medicines in areas of unmet medical need. Our Chief Executive Officer, as the chief operating decision-maker (“CODM”), manages and allocates resources to the operations of our company on an entity-wide basis. Managing and allocating resources on an entity-wide basis enables our CODM to assess the overall level of resources available and how to best deploy these resources across functions and research and development (“R&D”) projects based on unmet medical need, scientific data, probability of technical and regulatory successful development, market potential and other considerations, and, as necessary, reallocate resources among our internal R&D portfolio and external opportunities to best support the long-term growth of our business. Summary of Significant Accounting Policies Basis of Presentation The accompanying Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles and include the accounts of Gilead, our wholly-owned subsidiaries and any variable interest entities (“VIEs”) for which we are the primary beneficiary. All intercompany transactions have been eliminated. For any consolidated entities where we own or are exposed to less than 100% of the economics, we record net income or loss attributable to noncontrolling interests in our Consolidated Statements of Income equal to the attributable economic or ownership interest retained in such entities by the respective noncontrolling parties. When we obtain a variable interest in another entity, we assess at the inception of the relationship and upon occurrence of certain significant events whether the entity is a VIE and, if so, whether we are the primary beneficiary of the 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. 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, we evaluate our significant accounting policies and 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. Estimates are assessed each period and updated to reflect current information. Actual results may differ significantly from these estimates. Beginning in the first quarter of 2023, we reclassified changes in income taxes prepaid and receivable from Prepaid expenses and other to combine them with changes in income taxes payable as Income tax assets and liabilities, net within Operating Activities on our Consolidated Statements of Cash Flows. We believe this presentation assists users of the financial statements to better understand cash flow movements. Prior periods have been revised to reflect this change, resulting in a reclassification of $204 million and $3 million from Prepaid expenses and other for the years ended December 31, 2022 and 2021, respectively. Certain amounts and percentages herein may not sum or recalculate due to rounding. Revenue Recognition Product Sales We recognize revenue from product sales when control of the product transfers to the customer, which is generally upon shipment or delivery, or in certain cases, upon the corresponding sales by our customer to a third party. Revenues are recognized net of estimated rebates and chargebacks, patient co-pay assistance, prompt pay discounts, distributor fees, sales return provisions and other related deductions. These deductions to product sales are referred to as gross-to-net deductions and are estimated and recorded in the period in which the related product sales occur. Our payment terms to customers generally range from 30 to 90 days; however, payment terms differ by jurisdiction, by customer and, in some instances, by type of product. Revenues from product sales, net of gross-to-net deductions, are recorded only to the extent a significant reversal in the amount of cumulative revenue recognized is not probable of occurring when the uncertainty associated with gross-to-net deductions is subsequently resolved. Taxes assessed by governmental authorities and collected from customers are excluded from product sales. If we expect, at contract inception, that the period between the transfer of control and corresponding payment from the customer will be one year or less, we do not adjust the amount of consideration for the effects of a financing component. Shipping and handling activities are considered to be fulfillment activities and not a separate performance obligation. Gross-to-Net Deductions Rebates and Chargebacks Rebates and chargebacks are based on contractual arrangements or statutory requirements and include amounts due to payers and healthcare providers under various programs. These amounts may vary by product, payer and individual plans. Providers qualified under certain programs can purchase our products through wholesalers or other distributors at a discount. The wholesalers or distributors then charge the discount back to us. Rebates and chargebacks are estimated primarily based on product sales, including product mix and pricing, historical and estimated payer mix and discount rates, among other inputs, which require significant estimates and judgment. We assess and update our estimates each reporting period to reflect actual claims and other current information. Chargebacks that are payable to our direct customers are generally classified as reductions of Accounts receivable on our Consolidated Balance Sheets. Rebates that are payable to third party payers and healthcare providers are recorded in Accrued rebates on our Consolidated Balance Sheets. Patient Co-Pay Assistance Co-pay assistance represents financial assistance to qualified patients, assisting them with prescription drug co-payments required by insurance. Our accrual for copay is based on an estimate of claims and the cost per claim that we expect to receive associated with inventory that exists in the distribution channel at period end. Cash Discounts We estimate cash discounts based on contractual terms, historical customer payment patterns and our expectations regarding future customer payment patterns. Distributor Fees Under our inventory management agreements with our significant U.S. wholesalers, we pay the wholesalers a fee primarily for compliance with certain contractually-determined covenants such as the maintenance of agreed-upon inventory levels. These distributor fees are based on a contractually-determined fixed percentage of sales. Allowance for Sales Returns Allowances are made for estimated sales returns by our customers and are recorded in the period the related revenue is recognized. We typically permit returns if the product is damaged, defective, or otherwise cannot be used by the customer. In the U.S., we typically permit returns six months prior to and up to one year after the product expiration date. Outside the U.S., returns are only allowed in certain countries on a limited basis. Our estimates of sales returns are based primarily on analysis of our historical product return patterns, industry information reporting the return rates for similar products and contractual agreement terms. We also take into consideration known or expected changes in the marketplace specific to each product. Royalty, Contract and Other Revenues Royalty revenue is recognized in the period in which the obligation is satisfied and the corresponding sales by our corporate partners occur. Contract and other revenues are recognized when the performance obligation is satisfied. Research and Development Expenses Research and development expenses are recorded when incurred and consist primarily of personnel costs including salaries, benefits and stock-based compensation expense, infrastructure, materials and supplies and other support costs, research and clinical studies performed by contract research organizations (“CROs”) and our collaboration partners and other outside services. From time to time, we enter into development and collaboration agreements in which we share expenses with a collaborative partner. We record payments received from our collaborative partners for their share of the development costs as a reduction of Research and development expenses. Clinical study costs are a significant component of Research and development expenses. Most of our clinical studies are performed by third-party CROs. We monitor levels of performance under each significant contract including the extent of patient enrollment and other activities through communications with our CROs. We accrue costs for clinical studies performed by CROs over the service periods specified in the contracts and adjust our estimates, if required, based upon our ongoing review of the level of effort and costs actually incurred by the CROs. All of our material CRO contracts are terminable by us upon written notice and we are generally only liable for actual services completed by the CRO and certain non-cancelable expenses incurred at any point of termination. Payments we make for R&D services prior to the services being rendered are recorded as prepaid assets within Prepaid and other current assets on our Consolidated Balance Sheets and are expensed as the services are provided. Acquired In-Process Research and Development Expenses Acquired in-process research and development expenses are recorded when incurred and reflect costs of externally-developed in-process research and development (“IPR&D”) projects, acquired directly in a transaction other than a business combination, that do not have an alternative future use, including upfront and milestone payments related to various collaborations and the costs of rights to IPR&D projects. Selling, General and Administrative Expenses Selling, general and administrative expenses are recorded when incurred and consist primarily of personnel costs, facilities and overhead costs, and sales, marketing and advertising expenses, as well as other general and administrative costs related to finance, human resources, legal and other administrative activities. Advertising expenses within Selling, general and administrative expenses, including promotional expenses, are recorded when incurred and were $826 million, $778 million and $735 million for the years ended December 31, 2023, 2022 and 2021, respectively. Stock-Based Compensation We provide stock-based compensation in the form of various types of equity-based awards, including restricted stock units (“RSUs”), performance share units (“PSUs”) and stock options, and through our Employee Stock Purchase Plan and the International Employee Stock Purchase Plan (together, as amended, the “ESPP”). Stock-based compensation expense is based on the estimated fair value of the award on the grant date, or the first date of the ESPP purchase period, and recognized over the requisite service periods on our Consolidated Statements of Income using the straight-line expense attribution approach, reduced for estimated forfeitures. We estimate forfeitures based on our historical experience. The requisite service period could be shorter than the vesting period if an employee is retirement eligible or if an employee terminates due to death or disability. The estimated fair value of RSUs is based on the closing price of our common stock on the grant date. For PSUs, depending on the terms of the award, fair value on the date of grant is determined based on either the Monte Carlo valuation methodology or the closing stock price on the date of grant. For stock option and ESPP awards, estimated fair value is based on the Black-Scholes option valuation model. Estimated inputs to that model include (i) expected volatility, based on a blend of historical volatility of our common stock price along with implied volatility for traded options on our common stock, (ii) expected term in years, based on the weighted-average period awards are expected to remain outstanding using historical cancellation and exercise data, contractual terms and vesting terms of the award, (iii) risk-free interest rate, based on observed interest rates appropriate for the term of the stock-based awards, and (iv) expected dividend yield, based on our history and expectation of dividend payments. Earnings Per Share Basic earnings per share attributable to Gilead is calculated based on Net income attributable to Gilead on our Consolidated Statements of Income divided by the weighted-average number of shares of our common stock outstanding during the period. Diluted earnings per share attributable to Gilead is calculated based on Net income attributable to Gilead on our Consolidated Statements of Income divided by the weighted-average number of shares of our common stock and other dilutive securities outstanding during the period. The potentially dilutive shares of our common stock resulting from the assumed exercise of outstanding stock options and equivalents are determined under the treasury stock method. Cash and Cash Equivalents We consider highly liquid investments with insignificant interest rate risk and an original maturity of three months or less on the purchase date to be cash equivalents. Marketable Debt Securities All of our marketable debt securities are classified as available-for-sale and recorded at estimated fair values. We determine the appropriate classification of our marketable debt securities at the time of purchase and reevaluate such designation at each balance sheet date. Unrealized gains and losses on available-for-sale debt securities are reported in Accumulated other comprehensive income on our Consolidated Balance Sheets until realized, at which point they are reclassified into Other income (expense), net on our Consolidated Statements of Income. We regularly review our investments for declines in fair value below their amortized cost basis to determine whether the impairment is due to credit-related factors or noncredit-related factors. Our review includes the creditworthiness of the security issuers, the severity of the unrealized losses, whether we have the intent to sell the securities and whether it is more likely than not that we will be required to sell the securities before the recovery of their amortized cost bases. When we determine that a portion of the unrealized loss is due to an expected credit loss, we recognize the loss amount in Other income (expense), net, with a corresponding allowance against the carrying value of the security we hold. The portion of the unrealized loss related to factors other than credit losses is recognized in Accumulated other comprehensive income. Interest and amortization of purchase premiums and discounts are also recorded in Other income (expense), net on our Consolidated Statements of Income. The cost of securities sold is based on the specific identification method. Accounts Receivable Trade accounts receivable are recorded net of allowances for wholesaler chargebacks related to government and other programs, cash discounts for prompt payment and estimated credit losses. Estimates of our allowance for credit losses consider a number of factors, including existing contractual payment terms, individual customer circumstances, historical payment patterns of our customers, a review of the local economic environment and its potential impact on expected future customer payment patterns and government funding and reimbursement practices. Inventories Inventories are recorded at the lower of cost or net realizable value, with cost determined on a first-in, first-out basis. We periodically review our inventories to identify obsolete, slow-moving, excess or otherwise unsaleable items. If obsolete, slow-moving, excess or unsaleable items are observed and there are no alternate uses for the inventory, we record a write-down to net realizable value through a charge to Cost of goods sold on our Consolidated Statements of Income. The determination of net realizable value requires judgment, including consideration of many factors, such as estimates of future product demand, product net selling prices, current and future market conditions and potential product obsolescence, among others. When future commercialization is considered probable and the future economic benefit is expected to be realized, based on management’s judgment, we capitalize pre-launch inventory costs prior to regulatory approval. A number of factors are considered, including the current status in the regulatory approval process, potential impediments to the approval process such as safety or efficacy, anticipated R&D initiatives that could impact the indication in which the compound will be used, viability of commercialization and marketplace trends. Equity Securities Equity securities with readily determinable fair values, including those for which we have elected the fair value option, are recorded at fair market value, and unrealized gains and losses are included in Other income (expense), net on our Consolidated Statements of Income. Equity securities without readily determinable fair values are recorded using the measurement alternative of cost less impairment, if any, adjusted for observable price changes in orderly transactions for identical or similar investments of the same issuer. Any impairments or adjustments are recorded in Other income (expense), net on our Consolidated Statements of Income. For investments in entities over which we have significant influence but do not meet the requirements for consolidation and have not elected the fair value option, we use the equity method of accounting, with our share of the underlying income or loss of such entities reported in Other income (expense), net on our Consolidated Statements of Income. Our investments in equity securities are classified in Prepaid and other current assets or Other long-term assets on our Consolidated Balance Sheets, generally depending on marketability and whether the securities are subject to lock-up provisions. We regularly review our securities for indicators of impairment. Property, Plant and Equipment Property, plant and equipment is stated at cost less accumulated depreciation and amortization. Depreciation and amortization are recognized using the straight-line method. Repairs and maintenance costs are expensed as incurred. Estimated useful lives in years are generally as follows: Description Estimated Useful Life Buildings and improvements Shorter of 35 years or useful life Laboratory and manufacturing equipment 4-10 Office, computer equipment and other 3-15 Leasehold improvements Shorter of useful life or lease term See “Impairment of Long-Lived Assets” for additional information. Leases We determine if an arrangement contains a lease at inception and classify each lease as operating or financing. Right-of-use assets and lease liabilities are recognized at the commencement date based on the present value of the lease payments over the lease term, which is the non-cancelable period stated in the contract adjusted for any options to extend or terminate when it is reasonably certain that we will exercise that option. Right-of-use assets are adjusted for prepaid lease payments, lease incentives and initial direct costs incurred. Operating lease expense for the minimum lease payments is recognized on a straight-line basis over the lease term. We account for lease and nonlease components in our lease agreements as a single lease component in determining lease assets and liabilities. In addition, we do not recognize the right-of-use assets and liabilities for leases with lease terms of one year or less. As most of our operating leases do not provide an implicit interest rate, we generally utilize a collateralized incremental borrowing rate, applied in a portfolio approach when relevant, based on the information available at the commencement date to determine the lease liability. Acquisitions, including Goodwill, Intangible Assets and Contingent Consideration We account for business combinations using the acquisition method of accounting, which generally requires that assets acquired, including IPR&D projects, and liabilities assumed be recorded at their fair values as of the acquisition date on our Consolidated Balance Sheets. Any excess of consideration over the fair value of net assets acquired is recorded as goodwill. The determination of estimated fair value requires us to make significant estimates and assumptions. As a result, we may record adjustments to the fair values of assets acquired and liabilities assumed within the measurement period, which may be up to one year from the acquisition date, with the corresponding offset to goodwill. Transaction costs associated with business combinations are expensed as they are incurred. Intangible assets related to IPR&D projects are considered to be indefinite-lived until the abandonment or completion of the associated R&D efforts, which generally occurs when regulatory approval is obtained. Goodwill and indefinite-lived intangible assets are not amortized and, instead, are tested for impairment annually or more frequently if events or changes in circumstances indicate that it is more likely than not that the assets are impaired. Intangible assets with finite useful lives are amortized over their estimated useful lives, primarily on a straight-line basis, and, are also periodically reviewed for changes in facts or circumstances resulting in a reduction to the estimated useful life of the asset, requiring the acceleration of amortization. See “Impairment of Long-Lived Assets” for additional information. In determining the initial fair value of an intangible asset, or when quantitative analysis is required to determine any impairment, we use a probability-weighted income approach that discounts expected future cash flows to present value using a discount rate that is based on the estimated weighted-average cost of capital for companies with profiles similar to ours and represents the rate that market participants would use to value the intangible assets. These cash flow models require the use of Level 3 fair value measurements and inputs, including estimated revenues, which, for example, include significant inputs such as addressable patient population, treatment duration, projected market share, assessment of the asset’s life cycle, and competitive trends impacting the asset; costs and probability of technical and regulatory success, among other factors. 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 record contingent consideration resulting from a business combination at its fair value on the acquisition date. Each reporting period thereafter, we revalue these obligations and record increases or decreases in their fair value on our Consolidated Statements of Income until such time that the payment is made. Increases or decreases in fair value of the contingent consideration liabilities can result from updates to assumptions such as the expected timing or probability of achieving the specified milestones, changes in projected revenues or changes in discount rates. When we determine net assets acquired do not meet the definition of a business combination under the acquisition method of accounting, the transaction is accounted for as an asset acquisition and, therefore, no goodwill is recorded and contingent consideration generally is not recognized at the acquisition date. In an asset acquisition, upfront payments allocated to IPR&D projects at the acquisition date and subsequent milestone payments are expensed as incurred on our Consolidated Statements of Income unless there is an alternative future use. Impairment of Long-Lived Assets Long-lived assets, including property, plant and equipment and finite-lived intangible assets, are reviewed for impairment whenever facts or circumstances either internally or externally may indicate that the carrying value of an asset may not be recoverable. Should there be an indication of impairment, we test for recoverability by comparing the estimated undiscounted future cash flows expected to result from the use of the asset over its useful life to the carrying amount of the asset or asset group. If the asset or asset group is determined to be impaired, any excess of the carrying value of the asset or asset group over its estimated fair value is recognized as an impairment loss. Derivatives We recognize all derivative instruments as either assets or liabilities at fair value on our Consolidated Balance Sheets. Unrealized changes in the fair value of derivatives designated as part of a hedge transaction are recorded in Accumulated other comprehensive income. For our hedges related to forecasted product sales, the unrealized gains or losses in Accumulated other comprehensive income are reclassified into Product sales on our Consolidated Statements of Income when the respective hedged transactions affect earnings. Changes in the fair value of derivatives that are not part of a hedge transaction are recorded each period in Other income (expense), net on our Consolidated Statements of Income. Using regression analysis, we assess, both at inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are effective in offsetting the changes in cash flows or fair values of the hedged items. If we determine that a forecasted transaction is probable of not occurring, we discontinue hedge accounting for the affected portion of the hedge instrument, and any related unrealized gain or loss on the contract is recognized in Other income (expense), net on our Consolidated Statements of Income. Contingencies We recognize accruals for loss contingencies to the extent that we conclude that a loss is both probable and reasonably estimable. We accrue the best estimate of loss within a range; however, if no estimate in the range is better than any other, then we accrue the minimum amount in the range. If we determine that a material loss is reasonably possible, we disclose the possible loss or range of loss, or that the amount of loss cannot be estimated at this time. Income Taxes Our income tax provision is computed under the liability method. Significant estimates are required in determining our provision for income taxes. Some of these estimates are based on interpretations of applicable tax laws or regulations. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. We record a valuation allowance to reduce our deferred tax assets to the amounts that are more likely than not to be realized. We consider future taxable income, ongoing tax planning strategies and our historical financial performance in assessing the need for a valuation allowance. If we expect to realize deferred tax assets for which we have previously recorded a valuation allowance, we will reduce the valuation allowance in the period in which such determination is first made. We recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained upon examination by tax authorities based on the technical merits of the position. The tax benefit recognized in the Consolidated Financial Statements for a particular tax position is based on the largest benefit that is more likely than not to be realized. The amount of unrecognized tax benefits (“UTB”) is adjusted as appropriate for changes in facts and circumstances, such as significant amendments to existing tax law, new regulations or interpretations by tax authorities, new information obtained during a tax examination or resolution of an examination. We recognize both accrued interest and penalties, where appropriate, related to UTB in Income tax expense on our Consolidated Statements of Income. We have elected to account for the tax on Global Intangible Low-Taxed Income, enacted as part of the Tax Cuts and Jobs Act, as a component of tax expense in the period in which the tax is incurred. Stock Repurchases We use the par value method of accounting for our stock repurchases made under repurchase programs. Under the par value method, we record the par value of the shares repurchased to Common stock and the historical issuance cost over par value of the shares repurchased to Additional paid-in capital. The excess of the cost of the shares repurchased over these two amounts is then recorded to Retained earnings . Foreign Currency Translation and Transactions Our Consolidated Financial Statements are presented in U.S. dollars. The functional currency for most of our foreign subsidiaries is their local currency. Revenues, expenses, gains and losses for non-U.S. dollar functional currency entities are translated into U.S. dollars using average currency exchange rates for the period. Assets and liabilities for such entities are translated using exchange rates that approximate the rate at the balance sheet date. Foreign currency translation adjustments are recorded as a component of Accumulated other comprehensive income on our Consolidated Balance Sheets. Foreign currency transaction gains and losses on transactions not denominated in functional currency are recorded in Other income (expense), net, on our Consolidated Statements of Income. Fair Value Measurements We apply fair value accounting for all financial and non-financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. We define fair value as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities which are required to be recorded at fair value, we consider the principal or most advantageous market in which we would transact and the market-based risk measurements or assumptions that market participants would use in pricing the asset or liability, such as risks inherent in valuation techniques, transfer restrictions and credit risks. We determine the fair value using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows: • Level 1 inputs include quoted prices in active markets for identical assets or liabilities |