Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business	Business We are a biopharmaceutical company enabling scientific advancement through supporting the clinical development of high-value medicines. We do this by providing financing, licensing our technologies or both.
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation Our unaudited condensed consolidated financial statements include the financial statements of Ligand and its wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. We have included all adjustments, consisting only of normal recurring adjustments, which we considered necessary for a fair presentation of our financial results. These unaudited condensed consolidated financial statements and accompanying notes should be read together with the audited consolidated financial statements included in our 2025 Annual Report. Interim financial results are not necessarily indicative of the results that may be expected for the full year.
Segment Information	Segment Information The Company has one operating and reportable segment: investing in the clinical development and commercialization of high-value medicines. The Company’s Chief Operating Decision Maker (“CODM”) is Todd Davis, our Chief Executive Officer. The CODM uses net income (loss) as a single segment profit or loss measure to evaluate our single segment performance, and in deciding whether to reinvest into the existing assets, or to new potential opportunities. Our CODM relies on internal management reporting processes that provide information on segment operating income (loss) for making financial decisions and allocating resources. The CODM does not evaluate, manage or measure performance of segments using asset information.
Use of Estimates	Use of Estimates The preparation of the unaudited condensed consolidated financial statements in conformity with GAAP requires the use of estimates and assumptions that affect the amounts reported in the unaudited condensed consolidated financial statements and the accompanying notes. Actual results may differ from those estimates.
Revenue and Income	Revenue and Income Our revenue and income is generated primarily from royalties on sales of products commercialized by our partners, Captisol material sales, income from financial royalty assets, contract revenue for license fees, technical, regulatory and sales-based milestone payments, and income resulting from other royalty transactions. For all revenue transactions, we apply the following five-step model in accordance with ASC 606, Revenue from Contracts with Customers, in order to determine the revenue: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations, including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. Revenue from Intangible Royalty Assets We receive royalty revenue from intangible royalty assets on sales by our partners of products covered by patents that we or our partners own under contractual agreements. We do not have future performance obligations under these license arrangements. We generally satisfy our obligation to grant intellectual property rights on the effective date of the contract. However, we apply the royalty recognition constraint required under the guidance for sales-based royalties which requires a royalty to be recorded no sooner than when the underlying sale occurs. Therefore, royalties on sales of products commercialized by our partners are recognized in the quarter the product is sold. Our partners generally report sales information to us on a one quarter lag. Thus, we estimate the expected royalty proceeds based on an analysis of historical experience and interim data provided by our partners including their publicly announced sales. Differences between actual and estimated royalty revenues, which have not been material, are adjusted in the period in which they become known, typically the following quarter. Income from Financial Royalty Assets We recognize income from financial royalty assets when there is a reasonable expectation about the timing and amount of cash flows expected to be collected. Income is calculated by multiplying the carrying value of the financial royalty asset by the periodic effective interest rate. We account for financial royalty assets related to developmental pipeline or recently commercialized products on a non-accrual basis. Developmental pipeline products are non-commercialized, non-approved products that require FDA or other regulatory approval, and thus have uncertain cash flows. Newly commercialized products typically do not have an established reliable sales pattern, and thus have uncertain cash flows. Captisol Sales Revenue from Captisol sales is recognized when control of Captisol material is transferred or intellectual property license rights are granted to our customers in an amount that reflects the consideration we expect to receive from our customers in exchange for those products or rights. 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. For Captisol material or intellectual property license rights, we consider our performance obligation satisfied once we have transferred control of the product or granted the intellectual property rights, meaning the customer has the ability to use and obtain the benefit of the Captisol material or intellectual property license right. We recognize revenue for satisfied performance obligations only when we determine there are no uncertainties regarding payment terms or transfer of control. Sales tax and other taxes we collect concurrent with revenue-producing activities are excluded from revenue. We have elected to recognize the cost of freight and shipping when control over Captisol material has transferred to the customer as an expense in cost of Captisol. We expense incremental costs of obtaining a contract when incurred if the expected amortization period of the asset that we would have recognized is one year or less or the amount is immaterial. We did not incur any incremental costs of obtaining a contract during the periods reported. Contract Revenue Our contracts with customers often include variable consideration in the form of contingent milestone payments. We include contingent milestone payments in the estimated transaction price when it is probable a significant reversal in the amount of cumulative revenue recognized will not occur. These estimates are based on historical experience, anticipated results and our best judgment at the time. If the contingent milestone payment is based on sales, we apply the royalty recognition constraint and record revenue when the underlying sale has taken place. Significant judgments must be made in determining the transaction price for our sales of intellectual property. Because of the risk that products in development with our partners will not reach development milestones or receive regulatory approval, we generally recognize any contingent payments that would be due to us upon the development milestone or regulatory approval. Some customer contracts are sublicenses which require that we make payments to an upstream licensor related to license fees, milestones and royalties which we receive from customers. In such cases, we evaluate the determination of gross revenue as a principal versus net revenue as an agent reporting based on each individual agreement. Income Operating income includes milestone and royalty income received from other royalty transactions and transactions involving our intellectual property including, R&D funding arrangements, dispositions and the related contingent consideration.
Short-term Investments	Gain (loss) from short-term investments in our condensed consolidated statements of operations includes both realized and unrealized gain (loss) from our short-term investments in corporate equity securities, and realized gain (loss) from available-for-sale debt securities. Our investment policy is capital preservation and we only invest in U.S.-dollar denominated investments.
Accounts Receivable and Allowance for Credit Losses	Accounts Receivable and Allowance for Credit Losses Our accounts receivable arise primarily from sales on credit to customers. We establish an allowance for credit losses to present the net amount of accounts receivable expected to be collected. The allowance is determined by using the loss-rate method, which requires an estimation of loss rates based upon historical loss experience adjusted for factors that are relevant to determining the expected collectability of accounts receivable. Some of these factors include macroeconomic conditions that correlate with historical loss experience, delinquency trends, aging behavior of receivables and credit and liquidity quality indicators for industry groups, customer classes or individual customers.
Inventory	Inventory Inventory, which consists of finished goods (Captisol), is stated at the lower of cost or net realizable value. We determine cost using the specific identification method. We analyze our inventory levels periodically and write down inventory to net realizable value if it has become obsolete, has a cost basis in excess of its expected net realizable value or is in excess of expected requirements.
Financial Royalty Assets, net	Financial Royalty Assets, net Financial royalty assets represent a portfolio of future milestone and royalty payment rights acquired that are passive in nature (i.e., we do not own the intellectual property or have the right to commercialize the underlying products). Although a financial royalty asset does not have the contractual terms typical of a loan (such as contractual principal and interest), we account for financial royalty assets under ASC 310, Receivables. Our financial royalty assets are classified similar to loans receivable and are measured at amortized cost using the prospective effective interest method described in ASC 835-30 Imputation of Interest. The effective interest rate is calculated by forecasting the expected cash flows to be received over the life of the asset relative to the initial invested amount. The effective interest rate is recalculated in each reporting period as the difference between expected cash flows and as actual cash flows are realized and as there are changes to expected future cash flows. The gross carrying value of a financial royalty asset is made up of the opening balance, or net purchase price for a new financial royalty asset, which is increased by accrued interest income (except for assets under the non-accrual method) and decreased by cash receipts in the period to arrive at the ending balance. We evaluate financial royalty assets for recoverability on an individual basis by comparing the effective interest rate at each reporting date to that of the prior period. If the effective interest rate is lower for the current period than the prior period, and if the gross cash flows have declined (expected and collected), we record provision expense for the change in expected cash flows. The provision is measured as the difference between the financial royalty asset’s amortized cost basis and the net present value of the expected future cash flows, calculated using the prior period’s effective interest rate. In a subsequent period, if there is an increase in expected future cash flows, or if actual cash flows are greater than cash flows previously expected, we reduce the previously established cumulative allowance in part or in full. In addition to the above allowance, we recognize an allowance for current expected credit losses under ASC 326, Financial Instruments – Credit Losses on our financial royalty assets. The credit rating, which is primarily based on publicly available data and updated quarterly, is the primary credit quality indicator used to determine the credit loss provision. The carrying value of financial royalty assets is presented net of the cumulative allowances for changes in expected future cash flows and expected credit losses. The initial amount and subsequent revisions in allowances for changes in expected future cash flows and expected credit losses are recorded as part of general and administrative expenses on the condensed consolidated statements of operations. When we are reasonably certain that a part of a financial royalty asset’s net carrying value (or all of it) is not recoverable, we recognize an impairment which is recorded in financial royalty assets impairment on the consolidated statements of operations. To the extent there was an allowance previously recorded for this asset, the amount of such impairment is written off against the allowance at the time that such a determination is made. Any future recoveries from such impairment are recognized when cash is collected in a respective period earnings. The short-term portion of financial royalty assets represents an estimation for current quarter royalty receipts which are normally collected during the subsequent quarter, and, as applicable, also includes royalty receipts from previous periods that have not been collected.
Research and Development Funding Expense	Research and Development Funding Expense We enter into transactions where we agree to fund a portion of the research and development (“R&D”) performed by our partners for products undergoing late-stage clinical trials in exchange for future royalties or milestones if the products are successfully developed and commercialized. In accordance with ASC 730, Research and Development, we account for the funded amounts as R&D expense when we have the ability to obtain the results of the R&D, the transfer of financial risk is genuine and substantive and, at the time of entering into the transaction, it is not yet probable that the product will receive regulatory approval. If these conditions are not met, we may record the funded amounts as a financial royalty asset. We may fund R&D upfront or over time as the underlying products undergo clinical trials. Royalties earned on successfully commercialized products generated from R&D arrangements are recognized as revenue from intangible royalty assets in the same period in which the sale of the commercialized product occurs. Fixed or milestone payments receivable based on the achievement of contractual criteria for products arising out of our R&D arrangements are recognized as contract revenue and other income in the period that the milestone threshold is met.
Derivative Assets	Derivative Assets As of March 31, 2026, all our derivative assets are warrants and options which are not used for risk management purposes. For additional information, see Note 3, Investment Transactions. As a result of our early adoption of ASU 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606) (“ASU 2025-07”), certain assets previously accounted for as derivatives have been qualified for a new derivative scope exception introduced by ASU 2025-07, and are now accounted for as financial royalty assets with January 1, 2025 being the effective date of ASU 2025-07 adoption. Such assets include (1) our rights in future milestone and royalty payments from Agenus partner programs, (2) rights to receive from Primrose Bio 50% of milestone payments on certain contracts previously entered into by Primordial Genetics (“Primrose mRNA”), and (3) Castle Creek Milestone (as defined in Note 3, Investment Transactions). For additional information, see Note 4, Financial Royalty Assets, net. All derivatives are measured at fair value on the condensed consolidated balance sheets.
Equity Method Investments	Equity Method Investments The Company accounts for investments in entities over which it has significant influence (generally defined as ownership interest of 20% or more) using the equity method of accounting. Under this method the investment is initially recorded at cost and subsequently adjusted for the Company’s share of the investee’s earnings or losses and any dividends received, unless the fair value option under ASC 825-10 is elected. Such selection is made on an instrument-by-instrument basis and is irrevocable. Equity method investments the Company elected a fair value option for are measured at fair value with changes in fair value recognized in earnings each reporting period and presented in gain (loss) from change in fair value of equity method investments and other investments in our condensed consolidated statements of operations. The Company elected the fair value option for the equity method investment in Pelthos. The election was made to simplify the accounting and reporting process, as Pelthos is a publicly traded entity with readily available market price. Equity method investments the Company did not elect a fair value option for are evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. Any impairment of equity method investments is presented in gain (loss) from change in fair value of equity method investments and other investments in our condensed consolidated statements of operations. Our equity method investments are reviewed for indicators of impairment at each reporting period and are written down to fair value if there is evidence of a loss in value that is other-than-temporary. The Company did not elect a fair value option for the equity method investment in Primrose Bio. There was no impairment to our equity method investments during the three months ended March 31, 2026 and 2025. The equity method investment in Primrose Bio is adjusted for the Company’s share of the investee’s earnings or losses and any dividends received. Any income or loss from our share of Primrose earnings or losses is presented in other non-operating expense, net in our condensed consolidated statement of operations. The Company does not record our share of the investee’s losses beyond the zero basis. The Company resumes recognition of our share of earnings only after the cumulative unrecognized losses have been recovered. As of December 31, 2024, the equity method investment in Primrose Bio had been written down to zero. We have no outstanding advances, guarantees, or commitment to fund Primrose Bio’s losses. Therefore, our proportionate share of net loss of Primrose Bio for the three months ended March 31, 2026 and 2025 was not recorded. Ligand owned 31.4% and 31.5% of the equity of Primrose Bio as of March 31, 2026 and December 31, 2025, respectively.
Other Investments	Other Investments Other investments represent our investments in equity securities of third parties in which we do not have control or significant influence. Our equity securities investments that do not have a readily determinable or estimable fair value are measured using the measurement alternative in accordance with ASC 321, which is cost less impairment, if any, and adjustments resulting from observable price changes in orderly transactions for the identical or similar investment of the same issuer. The amount of such impairment or adjustment recognized during the period is presented in gain (loss) from change in fair value of equity method investments and other investments in our condensed consolidated statements of operations. Our investment in Pelthos Series A preferred shares is measured at fair value with changes in fair value recognized in gain (loss) from change in fair value of equity method investments and other investments in our condensed consolidated statements of operations. For additional information, see Note 2, Pelthos Transaction.
Share-Based Compensation	Share-Based Compensation Share-based compensation expense for awards to employees and non-employee directors is a non-cash expense and is recognized on a straight-line basis over the vesting period.
Net Income (Loss) Per Share	Net Income (Loss) Per Share Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted average number of common shares outstanding during the period. Diluted net income per share is computed based on the sum of the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Diluted net loss per share is computed based on the sum of the weighted average number of common shares outstanding during the period. Potentially dilutive common shares consist of shares issuable under the 2030 Notes (as defined below), warrants in connection with the 2030 Notes, stock options and restricted stock. The 2030 Notes are considered to be Instrument C where, upon conversion, the Company must satisfy the accreted value of the debt instrument in cash and may choose to satisfy the conversion spread in cash, shares, or a combination of cash and shares. The dilutive effect of Instrument C is limited to the conversion premium, which is reflected in the calculation of diluted earnings per share as if it was a freestanding written call option on the issuer’s shares. The warrants will have a dilutive effect to the extent the market price per share of common stock exceeds the applicable exercise price of the warrants. Potentially dilutive common shares from stock options and restricted stock are determined using the average share price for each period under the treasury stock method. In addition, the following amounts are assumed to be used to repurchase shares: proceeds from exercise of stock options and the average amount of unrecognized compensation expense for the awards.
Foreign Currency Translation	Foreign Currency Translation The Euro is the functional currency of Apeiron and the corresponding financial statements have been translated into U.S. Dollars in accordance with ASC 830-30, Translation of Financial Statements. Assets and liabilities are translated at end-of-period rates while revenues and expenses are translated at average rates in effect during the period in which the activity took place. Equity is translated at historical rates and the resulting cumulative translation adjustments are included as a component of accumulated other comprehensive income (loss).
Accounting Standards Updates, Recently Adopted and Not Yet Adopted	Accounting Standards Not Yet Adopted In November 2024, the FASB issued ASU No. 2024-03, Income Statement—Reporting Comprehensive Income (Subtopic 220-40): Expense Disaggregation Disclosures. This update requires entities to disaggregate operating expenses into specific categories, such as salaries and wages, depreciation, and amortization, to provide enhanced transparency into the nature and function of expenses. ASU 2024-03 is effective for fiscal years beginning after December 15, 2026, with early adoption permitted. ASU 2024-03 may be applied retrospectively or prospectively. We are currently evaluating the new guidance to determine the impact it may have on our condensed consolidated financial statements and related disclosures. We do not believe that any other recently issued, but not yet effective accounting pronouncements, if adopted, would have a material impact on our condensed consolidated financial statements or disclosures.

LIGAND PHARMACEUTICALS INC 10-Q