Note 2. Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Basis of Presentation

Basis of Presentation. These consolidated financial statements include the accounts of First Solar, Inc. and its subsidiaries and are prepared in accordance with U.S. GAAP. We eliminated all intercompany transactions and balances during consolidation. Certain prior year balances were reclassified to conform to the current year presentation.

Use of Estimates

Use of Estimates. The preparation of consolidated financial statements in conformity with U.S. GAAP requires us to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and the accompanying notes. On an ongoing basis, we evaluate our estimates, including those related to accrued solar module collection and recycling liabilities, product warranties, and government grants. Despite our intention to establish accurate estimates and reasonable assumptions, actual results could differ materially from such estimates and assumptions.

Fair Value Measurements

Fair Value Measurements. We measure certain assets and liabilities at fair value, which is defined as the price that would be received from the sale of an asset or paid to transfer a liability (i.e., an exit price) on the measurement date in an orderly transaction between market participants in the principal or most advantageous market for the asset or liability. Our fair value measurements use the following hierarchy, which prioritizes valuation inputs based on the extent to which the inputs are observable in the market.

•Level 1 – Valuation techniques in which all significant inputs are unadjusted quoted prices from active markets for assets or liabilities that are identical to the assets or liabilities being measured.

•Level 2 – Valuation techniques in which significant inputs include quoted prices from active markets for assets or liabilities that are similar to the assets or liabilities being measured and/or or quoted prices for assets or liabilities that are identical or similar to the assets or liabilities being measured from markets that are not active.

•Level 3 – Valuation techniques in which one or more significant inputs are unobservable. Such inputs reflect our estimate of assumptions that market participants would use to price an asset or liability.

Cash and Cash Equivalents, Restricted Cash and Restricted Cash Equivalents

Cash and Cash Equivalents. We consider highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents with the exception of time deposits and U.S. Treasury securities, which are presented as marketable securities.

Restricted Cash and Restricted Cash Equivalents. Restricted cash and restricted cash equivalents consist of deposits held by various banks to secure certain of our letters of credit, as well as deposits held in custodial accounts to fund the estimated future costs of our solar module collection and recycling obligations. Restricted cash is classified as current or noncurrent based on the nature of the restriction.

Marketable Securities and Restricted Marketable Securities

Marketable Securities and Restricted Marketable Securities. We determine the classification of our marketable securities and restricted marketable securities at the time of purchase and reevaluate such designation at each balance sheet date. As of December 31, 2025 and 2024, all of our marketable securities and restricted marketable securities were classified as available-for-sale. Accordingly, we record them at fair value and account for the net unrealized gains and losses as part of “Accumulated other comprehensive loss” until realized. We record realized gains and losses on the sale of our marketable securities and restricted marketable securities in “Other expense, net” computed using the specific identification method.

We may sell marketable securities prior to their stated maturities after consideration of our liquidity requirements. Accordingly, we view unrestricted securities with maturities beyond 12 months as available to support our current operations and classify such securities as current assets under “Marketable securities” in our consolidated balance sheets. Restricted marketable securities consist of long-term duration marketable securities that we hold in custodial accounts to fund the estimated future costs of our solar module collection and recycling obligations. Accordingly, we classify restricted marketable securities as noncurrent assets under “Restricted marketable securities” in our consolidated balance sheets.

Accounts Receivables Trade

Accounts Receivable Trade. We record trade accounts receivable for our unconditional rights to consideration arising from our performance under contracts with customers. The carrying value of such receivables, net of the allowance for credit losses, represents their estimated net realizable value. Our module sales generally include payment terms between 30 and 90 days following the transfer of control of the products to the customer. In addition, certain module sales agreements require a down payment for a portion of the transaction price upon, or shortly after, entering into the agreement or related purchase order. As a practical expedient, we do not adjust the promised amount of consideration for the effects of a significant financing component when we expect, at contract inception, that the period between our transfer of a promised product to a customer and when the customer pays for that product will be one year or less.

We may sell trade accounts receivable to financial institutions under non-recourse or full recourse factoring arrangements. Under non‑recourse factoring arrangements, which qualify for sale accounting, the transferred receivables are derecognized from the consolidated balance sheets and proceeds are recorded as operating cash flows when control transfers to the financial institution. Any related fees or discounts are recorded in “Selling, general and administrative” expense. Under full‑recourse factoring arrangements, we retain the credit risk associated with the factored receivables and account for the transactions as secured borrowings, with proceeds recorded under “Other current liabilities” and related costs recognized as interest expense.

Allowance for Credit Losses

Allowance for Credit Losses. The allowance for credit losses is a valuation account that is deducted from a financial asset’s amortized cost to present the net amount we expect to collect from such asset. We monitor the estimated credit losses associated with our trade accounts receivable based primarily on our collection history, which we review annually, and the delinquency status of amounts owed to us, which we determine based on the aging of such receivables. We estimate credit losses associated with our marketable securities and restricted marketable securities based on the external credit ratings for such investments and the historical loss rates associated with such credit ratings, which we obtain from third parties. Such methods and estimates are adjusted, as appropriate, for relevant past events, current conditions, and reasonable and supportable forecasts. We recognize write-offs within the allowance for credit losses when cash receipts associated with our financial assets are deemed uncollectible.

Government Grants

Government Grants. We account for government assistance that is not subject to the scope of ASC 740 using a grant accounting model, by analogy to International Accounting Standards 20, Accounting for Government Grants and Disclosure of Government Assistance, and recognize such grants when we have reasonable assurance that we will

comply with the grant’s conditions and that the grant will be received. Government grants whose primary condition is the purchase, construction, or acquisition of a long-lived asset are considered asset-based grants and are recognized as a reduction to such asset’s cost basis, which reduces future depreciation. Other government grants not related to long-lived assets are considered income-based grants and are recognized as a reduction to the related cost of activities that generated the benefit. We recognize grants expected to be received directly from a government entity at their stated value. When we expect to transfer grants to a third party, we recognize the grants at, or adjust their carrying value to, the amount expected to be received from the transaction. Proceeds received from asset-based grants are presented as cash inflows from investing activities on the consolidated statements of cash flows, whereas proceeds received from income-based grants are presented as cash inflows from operating activities.

Inventories - Current and Noncurrent

Inventories – Current and Noncurrent. We report our inventories at the lower of cost or net realizable value. We determine cost on a first-in, first-out basis and include both the costs of acquisition and manufacturing in our inventory costs. These costs include direct materials, direct labor, and indirect manufacturing costs, including depreciation and amortization. Our capitalization of indirect costs is based on the normal utilization of our plants. If our plant utilization is abnormally low, the portion of our indirect manufacturing costs related to the abnormal utilization level is expensed as incurred. Other abnormal manufacturing costs, such as wasted materials or excess yield losses, are also expensed as incurred.

As needed, we may purchase critical raw materials that are used in our core production process in quantities that exceed anticipated consumption within our normal operating cycle, which is 12 months. We classify such raw materials that we do not expect to consume within our normal operating cycle as noncurrent.

We regularly review the cost of inventories, including noncurrent inventories, against their estimated net realizable value and record write-downs if any inventories have costs in excess of their net realizable values. We also regularly evaluate the quantities and values of our inventories, including noncurrent inventories, in light of current market conditions and trends, among other factors, and record write-downs for any quantities in excess of demand or for any obsolescence. This evaluation considers the use of modules for our product warranties, module selling prices, product obsolescence, strategic raw material requirements, and other factors.

Property, Plant and Equipment

Property, Plant and Equipment. We report our property, plant and equipment at cost, less accumulated depreciation. Cost includes the price paid to acquire or construct the assets, required installation costs, interest capitalized during the construction period, and any expenditures that substantially add to the value of or substantially extend the useful life of the assets. We expense repair and maintenance costs at the time we incur them.

We begin depreciation for our property, plant and equipment when the assets are placed in service. We consider such assets to be placed in service when they are both in the location and condition for their intended use. We compute depreciation expense using the straight-line method over the estimated useful lives of assets, as presented in the table below. We depreciate leasehold improvements over the shorter of their estimated useful lives or the remaining term of the lease. The estimated useful life of an asset is reassessed whenever applicable facts and circumstances indicate a change in the asset’s estimated useful life has occurred.

	Useful Lives in Years
Buildings and building improvements	25 – 40
Manufacturing machinery and equipment	5 – 15
Furniture, fixtures, computer hardware, and computer software	3 – 7
Leasehold improvements	up to 15

Asset Impairments

Asset Impairments. We assess long-lived assets classified as “held and used,” including our property, plant and equipment; lease assets; and intangible assets, for impairment whenever events or changes in circumstances arise, including consideration of technological obsolescence, that may indicate that the carrying amount of such assets may not be recoverable. These events and changes in circumstances may include a significant decrease in the market

price of a long-lived asset; a significant adverse change in the extent or manner in which a long-lived asset is being used, or in its physical condition; a significant adverse change in the business climate that could affect the value of a long-lived asset; an accumulation of costs significantly in excess of the amount originally expected for the acquisition or construction of a long-lived asset; a current-period operating or cash flow loss combined with a history of such losses or a projection of future losses associated with the use of a long-lived asset; or a current expectation that, more likely than not, a long-lived asset will be sold or otherwise disposed of significantly before the end of its previously estimated useful life. For purposes of recognition and measurement of an impairment loss, long-lived assets are grouped with other assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities.

When impairment indicators are present, we compare undiscounted future cash flows, including the eventual disposition of the asset group at market value, to the asset group’s carrying value to determine if the asset group is recoverable. If the carrying value of the asset group exceeds the undiscounted future cash flows, we measure any impairment by comparing the fair value of the asset group to its carrying value. Fair value is generally determined by considering (i) internally developed discounted cash flows for the asset group, (ii) third-party valuations, and/or (iii) information available regarding the current market value for such assets. If the fair value of an asset group is determined to be less than its carrying value, an impairment in the amount of the difference is recorded in the period that the impairment indicator occurs. Estimating future cash flows requires significant judgment, and such projections may vary from the cash flows eventually realized.

We consider a long-lived asset to be abandoned after we have ceased use of the asset and we have no intent to use or repurpose it in the future. Abandoned long-lived assets are recorded at their salvage value, if any.

We classify long-lived assets or asset groups we plan to sell as “held for sale” on our consolidated balance sheets only after certain criteria have been met, including: (i) management has the authority and commits to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and the plan to sell the asset have been initiated, (iv) the sale of the asset is probable within 12 months, (v) the asset is being actively marketed at a reasonable sales price relative to its current fair value, and (vi) it is unlikely that the plan to sell will be withdrawn or that significant changes to the plan will be made. We record assets or asset groups held for sale at the lower of their carrying value or fair value less costs to sell. If, due to unanticipated circumstances, such assets or asset groups are not sold in the 12 months after being classified as held for sale, then classification as held for sale would continue as long as the above criteria are still met.

Goodwill

Goodwill. Goodwill represents the excess of the purchase price of acquired businesses over the estimated fair value assigned to the individual assets acquired and liabilities assumed. We do not amortize goodwill, but instead test goodwill for impairment at least annually. We perform impairment tests between the scheduled annual test in the fourth quarter if facts and circumstances indicate that it is more likely than not that the fair value of a reporting unit that has goodwill is less than its carrying value.

We may first make a qualitative assessment of whether it is more likely than not that a reporting unit’s fair value is less than its carrying value to determine whether it is necessary to perform a quantitative goodwill impairment test. Such qualitative impairment test considers various factors, including macroeconomic conditions, industry and market considerations, cost factors, the overall financial performance of a reporting unit, and any other relevant events affecting our company or a reporting unit. If we determine through the qualitative assessment that a reporting unit’s fair value is more likely than not greater than its carrying value, the quantitative impairment test is not required; otherwise, we perform a quantitative impairment test. We may also decide to proceed directly to the quantitative impairment test without considering qualitative factors.

The quantitative impairment test is the comparison of the fair value of a reporting unit with its carrying amount, including goodwill. We define the fair value of a reporting unit as the price that would be received to sell the unit as a whole in an orderly transaction between market participants at the measurement date. Our modules business represents our only reporting unit, and we primarily use an income approach to estimate its fair value. Significant

judgment is required when estimating the fair value of a reporting unit, including the forecasting of future operating results and the selection of discount and expected future growth rates used to determine projected cash flows. If the estimated fair value of a reporting unit exceeds its carrying value, goodwill is not impaired, and no further analysis is required. Conversely, if the carrying value of a reporting unit exceeds its estimated fair value, we record an impairment loss equal to the excess, not to exceed the total amount of goodwill allocated to the reporting unit.

Intangible Assets

Intangible Assets. Intangible assets primarily include acquired technologies, in-process R&D (“IPR&D”) from prior business acquisitions, and our internally-generated intangible assets, substantially all of which are patents on technologies related to our products and production processes. We record an asset for patents after the patent has been issued based on the legal, filing, and other costs incurred to secure it. IPR&D is initially capitalized at fair value as an intangible asset with an indefinite life and periodically assessed for impairment. When the IPR&D project is complete, it is reclassified as a finite-lived intangible asset. We amortize finite-lived intangible assets on a straight-line basis over their estimated useful lives, which generally range from 5 to 20 years.

Supplier Finance Program

Supplier Finance Program. We participate in a supplier finance program. Under such program, certain suppliers may, at their sole discretion, elect to sell one or more of their receivables from us to a financial institution. Our payment obligations to the financial institution are not accelerated and remain subject to the original contractual terms agreed with the supplier; consequently, amounts payable under the program are included in “Accounts payable,” and payments made under the program are reported as operating cash flows. We do not provide guarantees or collateral in connection with these arrangements.

Leases

Leases. Upon commencement of a lease, we recognize a lease liability for the present value of the lease payments not yet paid, discounted using an interest rate that represents our ability to borrow on a collateralized basis over a period that approximates the lease term. We also recognize a lease asset, which represents our right to control the use of the underlying property, plant or equipment, at an amount equal to the lease liability, adjusted for prepayments, initial direct costs, and any incentives received.

We subsequently recognize the cost of operating leases on a straight-line basis over the lease term. Finance lease assets are amortized over the shorter of the estimated useful life of the underlying assets or the lease term, and interest expense on a finance lease liability is recognized using the effective interest method over the lease term. Any variable lease costs, which represent amounts owed to the lessor that are not fixed per the terms of the contract, are recognized in the period in which they are incurred. Any costs included in our lease arrangements that are not directly related to the leased assets, such as maintenance charges, are included as part of the lease costs. Leases with an initial term of one year or less are considered short-term leases and are not recognized as lease assets and liabilities. We recognize the cost of such short-term leases on a straight-line basis over the term of the underlying agreement.

Certain of our leases contain renewal or termination options that are exercisable at our discretion. At the commencement date of a lease, we include in the lease term any periods covered by a renewal option and exclude from the lease term any periods covered by a termination option, to the extent we are reasonably certain to exercise such options. In making this determination, the lease term applied would not exceed the expected economic life of the underlying asset.

Deferred Revenue

Deferred Revenue. When we receive consideration, or such consideration is unconditionally due, from a customer prior to transferring goods to the customer under the terms of a sales contract, we record deferred revenue, which represents a contract liability. Deferred revenue is classified as current or noncurrent based on the expected date that module shipments commence for each sales contract. As a practical expedient, we do not adjust the consideration in a contract for the effects of a significant financing component when we expect, at contract inception, that the period between a customer’s advance payment and our transfer of a promised product or service to the customer will be one year or less. Additionally, we do not adjust the consideration in a contract for the effects of a significant financing component when the consideration is received as a form of performance security.

Product Warranties

Product Warranties. We provide a limited PV solar module warranty covering defects in materials and workmanship under normal use and service conditions for up to 12.5 years. We also typically warrant that modules installed in accordance with agreed-upon specifications will produce at least 98% of their labeled power output rating during the first year, with the warranty coverage reducing by a degradation factor every year thereafter throughout the limited power output warranty period of up to 30 years. Among other potential issues, our solar module warranty also covers the resulting power output loss from cell cracking.

When we recognize revenue for sales of modules, we accrue liabilities for the estimated future costs of meeting our limited warranty obligations. We make and revise these estimates based primarily on the number of solar modules under warranty installed at customer locations, our historical experience with and projections of warranty claims, and our estimated per-module replacement costs. We also monitor our expected future module performance through certain quality and reliability testing and actual performance in certain field installation sites.

The classification of our warranty costs depends on the anticipated mode of settlement, which is either through product replacement or cash. We record warranty expense for anticipated claims we expect to resolve through the repair or replacement of modules as an increase to cost of sales, and those we expect to settle by cash payment as a reduction to revenue.

Accrued Solar Module Collection and Recycling Liability

Accrued Solar Module Collection and Recycling Liability. Historically, we recognized expense at the time of sale for the estimated cost of our future obligations for collecting and recycling solar modules covered by our solar module collection and recycling program. See Note 14. “Commitments and Contingencies” to our consolidated financial statements for further information.

Derivative Instruments

Derivative Instruments. We recognize derivative instruments on our consolidated balance sheets at fair value. On the date that we enter into a derivative contract, we designate the derivative instrument as a fair value hedge, a cash flow hedge, a hedge of a net investment in a foreign operation, or a derivative instrument that will not be accounted for using hedge accounting methods.

We record changes in the fair value of a derivative instrument that is designated and qualifies as a cash flow hedge in “Accumulated other comprehensive loss” until our earnings are affected by the variability of the cash flows from the underlying hedged item. We record any amounts excluded from effectiveness testing in current period earnings in the same income statement line item in which the earnings effect of the hedged item is reported. We report changes in the fair value of derivative instruments that are not designated or do not qualify for hedge accounting in current period earnings. We classify cash flows from derivative instruments on the consolidated statements of cash flows in the same category as the item being hedged or on a basis consistent with the nature of the instrument.

At the inception of a hedge, we formally document all relationships between hedging instruments and the underlying hedged items as well as our risk-management objective and strategy for undertaking the hedge transaction. We also formally assess (both at inception and on an ongoing basis) whether our derivative instruments are highly effective in offsetting changes in the fair value or cash flows of the underlying hedged items and whether those derivatives are expected to remain highly effective in future periods. When we determine that a derivative instrument is not highly effective as a hedge, we discontinue hedge accounting prospectively. When we discontinue hedge accounting and the derivative instrument remains outstanding, we carry the derivative instrument at its fair value on our consolidated balance sheets and recognize subsequent changes in its fair value in current period earnings.

Accumulated Other Comprehensive Income or Loss

Accumulated Other Comprehensive Income or Loss. Our accumulated other comprehensive income or loss includes foreign currency translation adjustments, unrealized gains and losses on available-for-sale debt securities, and unrealized gains and losses on derivative instruments designated and qualifying as cash flow hedges. We record these components of accumulated other comprehensive income or loss net of tax and release such tax effects when the underlying components affect earnings.

Revenue Recognition

Revenue Recognition. We recognize revenue for module sales at a point in time following the transfer of control of the modules to the customer, which typically occurs upon delivery of the modules to the location specified in the terms of the underlying contract. Our customer contracts generally contain provisions that require us to pay the customer liquidated damages if we fail to deliver modules by scheduled dates or if we fail to deliver modules that meet certain U.S. domestic content requirements. We recognize these liquidated damages as a reduction of revenue in the period we transfer control of the modules to the customer. Our customer contracts also generally contain provisions that entitle us to a termination payment if the customer defaults on its contractual obligations and the contract is terminated. We account for such terminations as contract modifications in the period of termination. We recognize revenue for bill-and-hold arrangements at the point in time the customer obtains control of the modules when all of the following criteria have been met: (i) the arrangement is substantive, (ii) the modules are segregated and identified separately as belonging to the customer, (iii) the modules are ready for physical transfer to the customer, and (iv) we do not have the ability to use the modules or direct them to another customer.

Shipping and Handling Costs. We account for shipping and handling activities related to contracts with customers as costs to fulfill our promise to transfer the associated products. Accordingly, we record amounts billed for shipping and handling costs as a component of net sales and classify such costs as a component of cost of sales.

Taxes Collected from Customers and Remitted to Governmental Authorities

Taxes Collected from Customers and Remitted to Governmental Authorities. We exclude from our measurement of transaction prices all taxes assessed by governmental authorities that are both (i) imposed on and concurrent with a specific revenue-producing transaction and (ii) collected from customers. Accordingly, such tax amounts are not included as a component of net sales or cost of sales.

Research and Development

Research and Development. We incur R&D costs during the process of researching and developing new products and enhancing our existing products, technologies, and manufacturing processes. Our R&D costs consist primarily of employee compensation, materials, outside services, and depreciation. We expense these costs as incurred until the resulting product has been completed, tested, and made ready for commercial manufacturing.

Production Start-Up

Production Start-Up. Production start-up expense consists of costs associated with operating a production line before it is qualified for commercial production, including the cost of raw materials for solar modules run through the production line during the qualification phase, employee compensation for individuals supporting production start-up activities, and applicable facility related costs. Production start-up expense also includes costs related to the selection of a new site and implementation costs for manufacturing process improvements to the extent we cannot capitalize these expenditures.

Share-Based Compensation

Share-Based Compensation. We recognize share-based compensation expense for the estimated grant-date fair value of equity awards issued as compensation to employees over the requisite service period, which is generally four or five years. For awards with performance conditions, we recognize share-based compensation expense if it is probable that the performance conditions will be achieved. We account for forfeitures of share-based awards as such forfeitures occur. Accordingly, when an associate’s employment is terminated, all previously unvested awards granted to the associate are forfeited, which results in a benefit to share-based compensation expense in the period of such associate’s termination equal to the cumulative expense recorded through the termination date for the unvested awards. We recognize share-based compensation expense for awards with graded vesting schedules on a straight-line basis over the requisite service periods for each separately vesting portion of the award as if each award was in substance multiple awards.

Foreign Currency Translation

Foreign Currency Translation. The functional currencies of certain of our foreign subsidiaries are their local currencies. Accordingly, we apply period-end exchange rates to translate their assets and liabilities and daily transaction exchange rates to translate their revenues, expenses, gains, and losses into U.S. dollars. We include the associated translation adjustments as a separate component of “Accumulated other comprehensive loss” within stockholders’ equity. The functional currency of our subsidiaries in Malaysia, Singapore, and Vietnam is the U.S. dollar; therefore, we do not translate their financial statements. Gains and losses arising from the

remeasurement of monetary assets and liabilities denominated in currencies other than a subsidiary’s functional currency are included in “Foreign currency loss, net” in the period in which they occur.

Income Taxes

Income Taxes. We use the asset and liability method to account for income taxes whereby we calculate deferred tax assets or liabilities using the enacted tax rates and tax law applicable to when any temporary differences are expected to reverse. We establish valuation allowances, when necessary, to reduce deferred tax assets to the extent it is more likely than not that such deferred tax assets will not be realized. We record taxes due on U.S. inclusions in taxable income related to Global Intangible Low-Taxed Income (“GILTI”) as a current-period expense when incurred. We do not provide deferred taxes related to the U.S. GAAP basis in excess of the outside tax basis in the investment in our foreign subsidiaries to the extent such amounts relate to indefinitely reinvested earnings and profits of such foreign subsidiaries.

Income tax expense includes (i) deferred tax expense, which generally represents the net change in deferred tax assets or liabilities during the year plus any change in valuation allowances, and (ii) current tax expense, which represents the amount of tax currently payable to or receivable from taxing authorities. We only recognize tax benefits related to uncertain tax positions that are more likely than not to be sustained upon examination. For those positions that satisfy such recognition criteria, the amount of tax benefit that we recognize is the largest amount of tax benefit that is more likely than not to be sustained when the uncertain tax position is ultimately settled.

Per Share Data

Per Share Data. Basic net income or loss per share is computed by dividing net income or loss by the weighted-average number of common shares outstanding for the period. Diluted net income per share is computed giving effect to all potentially dilutive common shares, including restricted stock and performance units, unless there is a net loss for the period. We use the treasury stock method to compute diluted net income per share