lgnd-20251231

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

_____________________________________________________________________________________________

FORM 10-K

_____________________________________________________________________________________________

For the Fiscal Year Ended December 31, 2025

For the transition period from to .

Commission File No. 001-33093

LIGAND PHARMACEUTICALS INCORPORATED

(Exact name of registrant as specified in its charter)

Jupiter

(Address of Principal Executive Offices) (Zip Code)

Registrant’s telephone number, including area code: (858) 550-7500

Securities registered pursuant to Section 12(b) of the Act:

Title of Each Class Trading Symbol Name of Each Exchange on Which Registered

Common Stock, par value $0.001 per share LGND The Nasdaq Global Market

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934. Yes ☐ No ☒

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definition of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Exchange Act Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the Registrant’s voting and non-voting stock held by non-affiliates was approximately $1.6 billion based on the last sales price of the Registrant’s Common Stock on the Nasdaq Global Market of the Nasdaq Stock Market LLC on June 30, 2025. For purposes of this calculation, shares of Common Stock held by directors, officers and 10% stockholders known to the Registrant have been deemed to be owned by affiliates which should not be construed to indicate that any such person possesses the power, direct or indirect, to direct or cause the direction of the management or policies of the Registrant or that such person is controlled by or under common control with the Registrant.

As of February 24, 2026, the Registrant had 19,941,141 shares of Common Stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Proxy Statement for the Registrant’s 2026 Annual Meeting of Stockholders to be filed with the Commission within 120 days of December 31, 2025 are incorporated by reference in Part III of this Annual Report on Form 10-K. With the exception of those portions that are specifically incorporated by reference in this Annual Report on Form 10-K, such Proxy Statement shall not be deemed filed as part of this Report or incorporated by reference herein.

Table of Contents

Part I

Item 1. Business 4

Item 1A. Risk Factors 19

Item 1B. Unresolved Staff Comments 49

Item 1C. Cybersecurity 49

Item 2. Properties 50

Item 3. Legal Proceedings 50

Item 4. Mine Safety Disclosures 51

Part II

Item 6. [Reserved] 52

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 59

Item 8. Consolidated Financial Statements and Supplementary Data 60

Item 9A. Controls and Procedures 108

Item 9B. Other Information 108

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 108

Part III

Item 10. Directors, Executive Officers and Corporate Governance 111

Item 11. Executive Compensation 111

Item 14. Principal Accountant Fees and Services 111

Part IV

Item 15. Exhibits, Financial Statement Schedules 113

GLOSSARY OF TERMS AND ABBREVIATIONS

Abbreviation Definition

Acrotech Acrotech Biopharma Inc.

Adalvo Adalvo Limited

Agenus Agenus Inc., Agenus Royalty Fund, LLC, and/or Agenus Holdings 2024, LLC

Aldeyra Aldeyra Therapeutics, Inc.

Amgen Amgen, Inc.

Arecor Arecor Therapeutics plc.

ASC Accounting Standards Codification

ASU Accounting Standards Update

Baxter Baxter International, Inc.

BendaRx BendaRx Corp.

BeOne Medicines BeOne Medicines I GmbH

BLA Biologics license application

CASI CASI Pharmaceuticals, Inc.

cGMP Current Good Manufacturing Practice

Company Ligand Pharmaceuticals Incorporated, including subsidiaries

COPD Chronic obstructive pulmonary disease

Cormatrix Cormatrix Cardiovascular, Inc.

Corvus Corvus Pharmaceuticals, Inc.

CVR Contingent value right

CyDex CyDex Pharmaceuticals, Inc.

Daiichi Sankyo Daiichi Sankyo Company, Ltd.

DMF Drug Master File

ESG Environmental, Social and Governance

ECM Extracellular matrix

Eisai Eisai Inc.

Elutia Elutia Inc. (f/k/a Aziyo Biologics, Inc.)

EPA Environmental Protection Agency

ESPP Employee Stock Purchase Plan, as amended and restated

EU European Union

Exelixis Exelixis, Inc.

FASB Financial Accounting Standards Board

FDA U.S. Food and Drug Administration

FY 2025 The Company’s fiscal year ended December 31, 2025

FY 2024 The Company’s fiscal year ended December 31, 2024

FY 2023 The Company’s fiscal year ended December 31, 2023

GAAP Generally accepted accounting principles in the United States

GCSF Granulocyte-colony stimulating factor

Gilead Gilead Sciences, Inc.

Hikma Hikma Pharmaceuticals PLC

Hovione Hovione FarmCiencia, S.A.

IND Investigational New Drug

InvIOs InvIOs Holding AG

IRS Internal Revenue Service

IV Intravenous

Jazz Jazz Pharmaceuticals, Inc.

LeonaBio LeonaBio, Inc.

Ligand Ligand Pharmaceuticals Incorporated, including subsidiaries

LTP Liver targeting prodrug

Marinus Marinus Pharmaceuticals, Inc.

Melinta Melinta Therapeutics, Inc.

Merck Merck & Co., Inc.

Metabasis Metabasis Therapeutics, Inc.

NDA New Drug Application

NOLs Net Operating Losses

Novan Novan, Inc. (n/k/a NVN Liquidation, Inc.)

Novartis Novartis AG

Nucorion Nucorion Pharmaceuticals, Inc.

OmniAb OmniAb Operations, Inc. (f/k/a OmniAb, Inc.)

Ono Ono Pharmaceutical Co., Ltd.

Opthea Opthea Limited

Orchestra Orchestra BioMed Holdings, Inc.

Orchestra BioMed Orchestra BioMed Holdings, Inc.

Palvella Palvella Therapeutics, Inc.

PDUFA Prescription Drug User Fee Act

Pfenex Pfenex Inc.

Pfizer Pfizer, Inc.

Phoenix Tissue Phoenix Tissue Repair

Primrose/Primrose Bio Primrose Bio, Inc.

PSU Performance stock unit

R&D Research and Development

Recordati Recordati Industria Chimica e Farmaceutica S.p.A

RSU Restricted stock unit

Sage Sage Therapeutics, Inc.

Sanofi Sanofi SA

SARM Selective Androgen Receptor Modulator

SEC Securities and Exchange Commission

Sedor Sedor Pharmaceuticals LLC, (assignee of RODES, Inc.)

Seelos Seelos Therapeutics, Inc.

Selexis Selexis, SA

Sermonix Sermonix Pharmaceuticals, LLC

SII Serum Institute of India

SQ Innovation SQ Innovation, Inc.

Sunshine Lake Pharma Sunshine Lake Pharma Co., Ltd.

Takeda Takeda Pharmaceuticals Company Limited

Tax Act The Tax Cuts and Jobs Act

Travere Travere Inc.

TR-Beta Thyroid hormone receptor beta

Vernalis Ligand UK Limited (f/k/a Vernalis plc)

Verona Verona Pharma plc

Viking Viking Therapeutics

Xi’an Xintong Xi’an Xintong Pharmaceuticals Research Co. Ltd.

PART I

Cautionary Note Regarding Forward-Looking Statements:

You should read the following report together with the more detailed information regarding our company, our common stock and our financial statements and notes to those statements appearing elsewhere in this document.

This report contains forward-looking statements, as defined in Section 21E of the Securities Exchange Act of 1934, as amended, that involve a number of risks and uncertainties and reflect Ligand’s judgment as of the date of this report. Although our forward-looking statements reflect the good faith judgment of our management, these statements can only be based on facts and factors currently known by us. Consequently, these forward-looking statements are inherently subject to risks and uncertainties, and actual results and outcomes may differ materially from results and outcomes discussed in the forward-looking statements.

All statements contained herein, other than statements of historical fact, could be deemed to be forward-looking statements. In some instances, forward-looking statements can be identified by the use of forward-looking words such as “believes,” “expects,” “may,” “will,” “plan,” “intends,” “estimates,” “would,” “continue,” “seeks,” “pro forma,” or “anticipates,” or other similar words (including their use in the negative), or by discussions of future matters such as those related to our future results of operations and financial position, royalties and milestones under license agreements, Captisol material sales, product development, and product regulatory filings and approvals, and the timing thereof, Ligand’s status as a high-growth company, as well as other statements that are not historical in nature. You should be aware that the occurrence of any of the events discussed in Part I under Item 1A under the caption “Risk Factors” of this report could negatively affect our results of operations, financial condition and the trading price of our stock.

The cautionary statements made in this report are intended to be applicable to all related forward-looking statements wherever they may appear in this report. We urge you not to place undue reliance on these forward-looking statements, which reflect our good-faith beliefs (or those of indicated third parties) and speak only as of the date of this report. Except as required by law, we disclaim any intent or obligation to update these forward-looking statements beyond the date of this report, even if new information becomes available in the future. This caution is made under the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934, as amended.

References to “Ligand Pharmaceuticals Incorporated,” “Ligand,” the “Company,” “we,” “our” and “us” include Ligand Pharmaceuticals Incorporated and our wholly-owned subsidiaries.

Partner Information

Information regarding partnered products and programs comes from information publicly released by our partners and licensees.

Trademarks

This Annual Report on Form 10-K includes trademarks, trade names and service marks owned by us. Ligand®, Captisol®, CyDex®, LTP®, LTP Technology®, NITRICILTM and Zelsuvmi® are protected under applicable intellectual property laws and are our property. All other trademarks, trade names and service marks including, but not limited to Pelican Expression Technology®, PeliCRM®, Pfenex Expression Technology®, OmniAb® Kyprolis®, Evomela®, Veklury®, Livogiva®, Bonteo®, Zulresso®, Rylaze®, VaxneuvanceTM, Pneumosil®, Minnebro®, Baxdela®, Nexterone®, Noxafil®, Duavee®, Filspari®, OhtuvayreTM, Qarziba® and Xepi® are the property of their respective owners. Solely for convenience, trademarks, trade names and service marks referred to in this report may appear without the ®, TM or SM symbols, but such references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the right of the applicable licensor to such trademarks, trade names and service marks. Use or display by us of other parties’ trademarks, trade dress or products is not intended to and does not imply a relationship with, or endorsement or sponsorship of, us by the trademark or trade dress owners.

Item 1. Business

Overview

We are a biopharmaceutical royalty company focused on deploying capital and licensing technologies to acquire and create diversified royalty streams from high-value medicines. Our primary business is investing in and structuring royalty interests in mid- to late-stage development and commercial biopharmaceutical products, allowing us to generate long-duration, non-dilutive cash flows supported by a lean corporate cost structure. Capital deployment and technology licensing are the primary drivers of our long-term growth.

We partner capital through a range of transaction structures—including royalty purchases, development-stage financing arrangements, and acquisitions of companies or assets with embedded royalty rights—designed to create cash flowing royalties and produce attractive risk-adjusted returns. Our goal is to provide investors with exposure to biopharmaceutical innovation through a diversified portfolio of royalty interests while mitigating the binary risk and capital intensity traditionally associated with drug development.

In addition to our royalty investment activities, we operate two infrastructure-light, royalty-generating platform technologies, Captisol® and NITRICIL®. These technologies exemplify our platform technology investment criteria: infrastructure-light, scalable intellectual property with existing royalty streams and the potential to generate incremental royalties through partner-driven development and commercialization.

Our revenue is generated primarily from royalties on sales of products commercialized by our partners, supplemented by Captisol material sales and contract revenue from license fees and milestone payments. We partner with leading biopharmaceutical companies to leverage their capabilities in late-stage development, regulatory execution, and commercialization, while we focus on disciplined capital deployment, portfolio construction, and risk management. This also allows us to leverage our partner's asset infrastructure in sales and marketing, manufacturing and R&D to avoid high cost infrastructure ourselves.

Strategy and Execution

Investment Strategy

We are a biopharmaceutical royalty aggregator, focused on disciplined capital allocation to differentiated late-stage assets and operation of royalty-generating, infrastructure-light platform technologies. We have 12 major commercial stage royalty assets comprising the majority of our royalty revenue. We maintain a portfolio of more than 90 additional commercial and development-stage programs. In 2022, Ligand made a strategic decision to refine our strategy and focus on a more efficient, high margin, low infrastructure version of our historical model. Following the spin-off of our OmniAb antibody discovery business in November 2022 and our Pelican Expression Technology subsidiary in September 2023, and continuing through and after the carve-out of our Pelthos Therapeutics business in July 2025 in connection with the Pelthos Transaction, our focus has been to continue to expand our pipeline by aggregating royalty rights in mid- to late-stage development and commercial biopharma products, while maintaining a lean infrastructure and high-margin business.

Our business model is highly differentiated from a traditional biotechnology company in several important ways. First, we have limited infrastructure requirements, enabling us to maintain relatively high operating margins. Second, we can enable development over a broad range of therapeutic areas and can be strategic and balanced about the size of our investments to achieve a highly diversified portfolio. Third, we believe our business model significantly mitigates the high volatility and risk associated with building a business around a single or small number of assets. With this approach, we have the ability to mitigate the impact of binary clinical outcomes inherent in the biopharmaceutical industry, thereby facilitating cash flows that are more predictable. Finally, we can target the size of our investments to achieve appropriate diversification across the portfolio.

Since refocusing the business in 2022, we have built a highly experienced business and investment team to execute our strategy. There is high demand for capital and low availability of structured capital in the segment of the biopharmaceutical market in which we operate, creating significant investment opportunities for Ligand. Unlike open-market equity investing, many of our investments take place under Confidential Disclosure Agreements and similar agreements of confidentiality (“CDAs”), facilitating access to in-depth proprietary information and data. Our flexible investment structures are designed to mitigate risks and help accommodate different transaction structures in line with our partners’ goals. We believe our business model is highly scalable and has significant growth potential. We have assembled a talented, long-tenured team with deep industry relationships, investment experience and industry knowledge.

Our investment opportunities are sourced through a combination of proprietary origination, deep industry relationships, and active engagement with biopharmaceutical partners. Our business development team works closely with potential counterparties under CDAs to access non-public clinical, regulatory and commercial diligence materials. This access allows us to evaluate opportunities earlier, structure transactions with greater precision, and selectively pursue investments with attractive,

asymmetric risk-reward profiles. This disciplined origination process, supported by experienced professionals with deep scientific and financial expertise, enhances our ability to access differentiated royalty and financing opportunities.

From a tactical perspective, we execute our business model using four key strategies: (1) royalty purchase and other royalty monetization transactions, (2) acquisitions of companies or assets with embedded royalty rights and other special situations, (3) project finance and other development-stage financing arrangements, and (4) IP technology platform investments.

1.With royalty monetization and other royalty monetization transactions, we purchase rights on existing royalty contracts that are owned by inventors, academic institutions or companies. There are advantages of royalty investing as a model because royalties 1) require minimal infrastructure, 2) are non-dilutable and 3) royalty flows are often protected in bankruptcy.

2.With acquisitions of companies or assets with embedded royalty rights and other special situations investing, we can acquire companies (via stock purchase, asset purchase, merger or other similar transaction) primarily as a means of accessing embedded royalty rights, partnered programs, or late-stage assets that can be monetized through royalties, rather than building and operating traditional drug development organizations. Ligand has an especially novel market position in this category as we are a team that has combined significant operating expertise with royalty investment experience. In this strategy, we acquire entire companies and then incubate, restructure and eventually hold onto the long-term royalty interests after shedding the infrastructure. Ligand’s track record of doing this successfully includes:

•Pharmacopeia acquisition, which yielded Travere’s Filspari

•Metabasis acquisition, which contributed to the creation of Viking Therapeutics

•Vernalis acquisition, which yielded Merck’s Ohtuvayre

•Pfenex acquisition, which yielded five of our major commercial royalty programs – Capvaxive, Vaxneuvance, Rylaze, Pneumosil, and Teriparatide, as well as our equity interest in Primrose Bio

•Novan acquisition, which yielded Zelsuvmi, our NITRICIL platform, and ultimately our equity interest in Pelthos following the completion of the Pelthos Transaction

•Apeiron acquisition, which yielded Qarziba

3. Project finance and other development-stage financing arrangements involves the provision of development capital to fund late-stage clinical programs in return for royalty contracts that we negotiate, creating synthetic royalties on the future sales of those products.

4. Finally, with IP technology platform acquisitions, we look for platforms that are infrastructure-light with existing royalties in place while providing the potential for generating new royalties through operating those platforms. Ideal

technology IP platforms will be scalable and have broad applicability. Our Captisol and NITRICIL businesses are excellent examples of successful platform technology investments.

We have a specific set of criteria we use to assess potential investments. The first is time to cash flow, as we typically seek products that are within a few years of regulatory approval and commercialization. We prioritize investments where the path to royalty monetization is clear and capital requirements beyond our investment is accessible. Typically, this means we invest in Phase 3 assets, although we also evaluate opportunities to invest from Phase 2 to approved assets. In terms of an asset’s clinical profile, we are looking for strong data supporting both efficacy and safety, and products which will ultimately deliver significant value to patients. We also look for strong market exclusivity, which can be achieved through intellectual property and/or regulatory protections. Structural alignment with our counterparty and the commercial partner is also a key criteria of the investments we make. Ultimately, we look for assets with favorable risk-reward profiles, which have above average probability of technical and regulatory success and can be commercialized effectively.

We have a disciplined investment process that guides us through our evaluation of potential investment opportunities. The process begins with proprietary origination, leveraging a seasoned investment team with deep industry expertise and strong relationships to source high-quality opportunities. Our investment progresses through a gated diligence framework that allocates resources across preliminary assessment, term-sheet development, and confirmatory diligence. A tailored proposal is constructed to align strategic objectives with the counterparty while optimizing our return potential. The process concludes with a comprehensive financial and legal due diligence review encompassing clinical, regulatory, commercial, intellectual property, and legal domains, culminating in a unanimous approval vote by our experienced three-member Investment Committee of the board of directors prior to entering into any binding term sheet and/or definitive documentation regarding our investment opportunities.

Performance

Since launching our more focused strategic investment approach in 2022, we have delivered meaningful and sustained revenue growth, reflecting improved execution, portfolio discipline, and an increased emphasis on high‐value opportunities. This approach has strengthened our core business, enhanced operating leverage, and supported continued investment in growth initiatives. Over this period, increased market recognition of our strategy and execution has also been reflected in appreciation of our stock price. We believe our focused approach enhances the durability of our business and supports our long‐term growth objectives.

Technologies

Our technology platforms are evaluated and managed as long-duration royalty assets. While these technologies are scientifically differentiated, their strategic role within Ligand is to generate recurring royalty revenue and optionality for incremental royalty creation through partner-driven development, rather than to support internally operated drug development programs.

Captisol Technology

Captisol is our largest and most established royalty-generating technology platform. Captisol is a patent-protected, chemically modified cyclodextrin with a structure designed to optimize the solubility and stability of drugs. This unique technology has enabled 17 FDA-approved products, including Gilead’s Veklury, Amgen’s Kyprolis, Baxter’s Nexterone, and Acrotech Biopharma’s Evomela. There are many Captisol-enabled products currently in various stages of development. We maintain a broad global patent portfolio for Captisol with the latest expiration date in 2033. Other patent applications covering methods of making Captisol, if issued, extend the expiration date to 2041.

In addition to solid Captisol powder, partners may access cGMP manufactured aqueous Captisol concentrate. This product offering was established in 2017 to reduce cycle time and increase Captisol production capacity for large-volume drug products. We maintain both Type IV and Type V DMFs with the FDA. These DMFs contain manufacturing and safety information relating to Captisol that our licensees can reference when developing Captisol-enabled drugs. We also have active DMFs in Japan, China and Canada.

NITRICIL Technology Platform

The NITRICIL technology platform was acquired through our Novan acquisition in 2023. The platform leverages nitric oxide’s naturally occurring antimicrobial and immunomodulatory properties to support the development of therapies addressing unmet medical needs across multiple therapeutic areas. NITRICIL enables “tunable” dosing through an adjustable drug release profile, allowing for proprietary formulations targeting a broad range of indications.

NITRICIL is currently leveraged in one FDA-approved product, Zelsuvmi, the first at-home FDA approved treatment for molluscum contagiosum. The platform is designed to support multiple royalty-bearing products, with Zelsuvmi representing the first commercial validation of NITRICIL’s potential to generate recurring royalty revenue across additional indications over time, primarily through partner-led development and commercialization.

HepDirect and LTP Technology Platform

The HepDirect and LTP technology platforms are our proprietary liver-targeting prodrug technologies that can deliver many different chemical classes of drugs to the liver by using a chemical modification that renders an active pharmaceutical ingredient (“API”) biologically inactive until cleaved by a liver-specific enzyme. These technologies may improve the efficacy and/or safety of certain drugs and can be applied to marketed or new drug products to treat liver diseases or diseases caused by hemostasis imbalance of circulating molecules controlled by the liver.

Pelican Expression Technology

The Pelican Expression Technology platform is owned and operated by Primrose Bio, in which Ligand held a 31.5% equity interest as of December 31, 2025. Ligand’s economic exposure to the platform is through its equity ownership and associated royalty and licensing arrangements, rather than through direct operational involvement.

The Pelican Expression Technology platform is a validated, scalable recombinant protein expression system used by global biopharmaceutical manufacturers for the production of complex biologics. The platform is currently licensed for multiple commercial and development-stage programs.

Ligand evaluates its investment in Pelican as part of its broader capital allocation strategy, with value derived from equity appreciation, royalties, and licensing income, without requiring Ligand to deploy or maintain operating infrastructure.

2025 Investment Highlights

In February 2025, we entered into a royalty financing agreement with Castle Creek Biosciences, Inc., a late-stage cell and gene therapy company, to support Castle Creek’s D-Fi (FCX-007) Phase 3 clinical study. D-Fi is an injectable autologous gene-modified cell therapy in development for the treatment of dystrophic epidermolysis bullosa (“DEB”) a devastating, painful, and debilitating rare genetic skin disorder. Under the terms of the agreement, we have invested $50 million in exchange for a mid-single digit royalty on worldwide sales of D-Fi and a portion of a future milestone payment upon D-Fi achieving FDA approval.

Throughout 2024 and into January of 2025, we acquired additional royalties from several Ohtuvayre inventors, bringing our total Ohtuvayre royalty to 3%.

On July 31, 2025, we invested $25 million in strategic capital to fund Orchestra BioMed Holdings, Inc.'s (“Orchestra” or “Orchestra Biomed”) late-stage partnered cardiology programs, consisting of a $20 million cash payment paid at closing and an additional $5 million to purchase shares of Orchestra’s common stock in an equity private placement at the price of $2.75 per share (the price of Orchestra’s common stock at its last public offering). Ligand also agreed to fund an additional $15 million, subject to certain conditions precedent, at the nine-month anniversary of the transaction closing date. In exchange, we received a low double-digit royalty on the first $100 million of Orchestra's annual revenues related to the AVIM and Virtue SAB programs in all indications. We will also earn a mid-single-digit royalty on Orchestra's annual revenues exceeding $100 million related to AVIM therapy in the uncontrolled hypertension and increased cardiovascular risk indication and Virtue SAB in coronary artery disease indications.We also received warrants to purchase shares of Orchestra’s common stock. The transaction closed on August 4, 2025.

On September 24, 2025, we invested $7 million in strategic capital to purchase economic rights from Arecor Limited (“Arecor”), with an additional $1 million in deferred consideration payable in two equal parts at the six- and twelve-month anniversaries of the transaction closing date.

In connection with the Arecor transaction, Ligand received the economic rights in two partner programs: 1) a single-digit royalty on global net sales of AT220, an Arestat®-enhanced biosimilar product marketed by a global pharmaceutical company; and 2) potential annual technology access fees and milestones from AT292 (efdoralprin alfa/SAR447537/INBRX-101), a partnered program with Sanofi. In addition to the economic rights, Ligand received warrants to purchase 1,002,739 ordinary shares of Arecor Therapeutics Plc, exercisable over a ten-year period. We are also obligated to pay up to $3 million in contingent consideration tied to commercial milestones in the AT292 partnered program.

See “Item 8. Financial Statements and Supplementary Data—Notes to Consolidated Financial Statements—Note 3, Investment Transactions.”

Pelthos Strategic Transaction

In July 2025, pursuant to an Agreement and Plan of Merger dated April 17, 2025 (the “Merger Agreement”), Ligand’s wholly owned subsidiary, LNHC, Inc. merged with and into CHRO Merger Sub Inc., a wholly owned subsidiary of Channel Therapeutics, and became a wholly owned subsidiary of Channel Therapeutics (the “Pelthos Transaction”). The merger was supported by $50 million in capital raised from a group of strategic investors led by Murchinson (“Investor Group”). The combined company now operates under the name Pelthos Therapeutics Inc. (“Pelthos”) and trades on the NYSE American exchange under the ticker “PTHS”.

Under the terms of the Merger Agreement, Channel acquired 100% of the issued and outstanding equity interests of Pelthos, and changed its name to Pelthos Therapeutics Inc. In connection with the transaction, we invested $18 million in the combined company and the Investor Group invested $32 million for a total of $50 million. As of December 31, 2025, we own approximately 48% of Pelthos’ outstanding shares of common stock, and approximately 60% of Pelthos outstanding shares of Series A convertible preferred stock.

The combined company is focused on accelerating the commercialization of Pelthos’ Zelsuvmi (berdazimer) topical gel, 10.3%, for the treatment of molluscum contagiosum infections (“molluscum”) in adults and pediatric patients one year of age and older. In July 2025, Pelthos commercially launched Zelsuvmi, the first U.S. FDA approved at-home treatment for molluscum contagiosum. We earned a $5 million milestone payment from Pelthos following the commercial launch of Zelsuvmi. We are also entitled to a 13% royalty on worldwide sales of Zelsuvmi, and up to an additional $5 million in commercial sales milestones.

In November 2025, we invested in Pelthos’ private convertible notes financing (the “Pelthos Convertible Notes Financing”) to support the acquisition and re-launch of Xepi by Pelthos and for other general business purposes. Xepi is a non-fluorinated quinolone antimicrobial indicated for the topical treatment of impetigo due to Staphylococcus aureus or Streptococcus pyogenes in adult and pediatric patients two months of age and older. We are entitled to a low single-digit royalty on U.S. net sales of Xepi.

See “Item 8. Financial Statements and Supplementary Data—Notes to Consolidated Financial Statements—Note 2, Pelthos Transaction.”

Commercial and Clinical Stage Partnered Portfolio

We have a large royalty portfolio including 12 major commercial-stage revenue-generating royalty assets and over 100 programs with future revenue-generating potential.

The following table provides an overview of royalty receipts on our commercial-stage revenue-generating royalty assets:

Kyprolis Amgen/Ono/Be One Medicines Oncology 1.5% - 3.0% $35.5 $1,529

Qarziba Recordati Oncology Tiered mid-teen $33.7 €159

Filspari Travere Nephropathy 9% $32.0 $355

Ohtuvayre 2 Merck Respiratory Disease 3% $14.8 $488

Rylaze Jazz Oncology Low single digit $13.3 $395

Capvaxive Merck Infectious Disease Low single digit $10.1 $752

Teriparatide Alvogen Women’s Health 25%-40% 1 $8.1 $34

Vaxneuvance Merck Infectious Disease Low single digit $7.4 $801

Evomela Acrotech/CASI Oncology 20% $5.9 $30

Nexterone Baxter Cardiovascular Low single digit $3.1 $81

Pneumosil SII Infectious Disease Low single digit $3.0 $129

Total Royalty Receipts $176.9

Less: Amortization of Financial Royalty Assets3 $15.9

GAAP Income from Royalty Assets $161.0

NOTES:

(1) We receive tiered profit sharing of 25% on quarterly profits less than $3.75 million, 35% on quarterly profits greater than $3.75 million but less than $7.5 million and 40% on quarterly profits greater than $7.5 million. If therapeutic equivalence is achieved, quarterly profit changes to 50% of quarterly profits.

(2) Ohtuvayre royalty receipts include an allocation of contractually earned milestones and royalties pertaining to financial royalty assets.

(3) Amounts represent the adjustments to the effective interest income recognized to total contractual payments recognized in the period.

Major Commercial-Stage Royalty Receipt Generating Assets

The following programs represent important revenue-generating components of our current portfolio. For information about the royalties owed to us for certain of these programs, see “Royalties” later in this business section.

Kyprolis (Amgen, Ono, BeOne Medicines)

We supply Captisol to Amgen for use with Kyprolis (carfilzomib) and granted Amgen an exclusive product-specific license under our patent rights with respect to Captisol. Kyprolis is formulated with Ligand’s Captisol technology and is approved in the following:

•In combination with dexamethasone, lenalidomide plus dexamethasone, daratumumab plus dexamethasone, or daratumumab and hyaluronidase-fihj and dexamethasone, or isatuximab and dexamethasone for the treatment of patients with relapsed or refractory multiple myeloma who have received one to three lines of therapy.

•As a single agent for the treatment of patients with relapsed or refractory multiple myeloma who have received one or more lines of therapy.

Our agreement with Amgen may be terminated by either party in the event of material breach or bankruptcy, or unilaterally by Amgen with prior written notice, subject to certain surviving obligations. Absent early termination, the agreement will terminate upon expiration of the obligation to pay royalties. Under this agreement, we are entitled to receive revenue from clinical and commercial Captisol material sales and a 1.5% to 3.0% royalty on annual net sales of Kyprolis. Amgen’s obligation to pay royalties does not expire until four years after the expiration of the last-to-expire patent covering Captisol. Our patents and applications relating to the Captisol component of Kyprolis are not expected to expire until at least 2033.

Qarziba (Recordati)

We receive royalties on Qarziba (dinutuximab beta) sales through our acquisition of Apeiron Biologics AG (“Apeiron”), announced in July 2024. Qarziba is a monoclonal antibody that is specifically directed against the carbohydrate moiety of disialoganglioside 2 (GD2), which is overexpressed on neuroblastoma cells. Dinutuximab beta was approved by the European Medicines Agency in 2017 for the treatment of high-risk neuroblastoma in patients aged 12 months and above, who have previously received induction chemotherapy and achieved at least a partial response, followed by myeloablative therapy and stem cell transplantation, as well as in patients with history of relapsed or refractory neuroblastoma, with or without residual

disease. Qarziba is commercially available in more than 35 countries outside of the U.S. We receive a tiered mid-teen royalty on worldwide sales of Qarziba from Recordati and are entitled to receive over $25 million in potential milestone payments.

Clinical Development of Qarziba

Qarziba is also in clinical development for additional territories and indications. Recordati met with the FDA mid-year in 2025 to establish a potential BLA pathway for the potential approval of Qarziba in the U.S., including data from the ongoing BEACON-2 trial in Europe. Results from the BEACON-2 trial are expected in 2028. Recordati is also currently conducting a clinical trial evaluating Qarziba + chemotherapy in GD2-positive Ewing sarcoma and has been granted orphan drug designation by the FDA.

See “Item 8. Financial Statements and Supplementary Data—Notes to Consolidated Financial Statements—Note 4, Acquisitions.”

Filspari (Travere, CSL Vifor, Chugai)

In early 2012, we licensed the world-wide rights to Filspari (sparsentan) to Travere Therapeutics. Travere received accelerated approval in February 2023 and then full approval in September 2024 from the FDA for Filspari, for the treatment of immunoglobulin A nephropathy (IgAN). Filspari is the first non-immunosuppressive treatment indicated for IgAN. In February 2024, Travere and its partner CSL Vifor received approval for Filspari for the treatment of IgAN in Europe. Travere has also partnered with Chugai Pharmaceuticals to develop and commercialize Filspari in Japan and other Asian countries. Under our license agreement with Travere, we are entitled to receive potential milestone payments, as well as a 9% royalty on worldwide sales.

Clinical Development of Filspari

Filspari is also in clinical development in additional territories and indications. Renalys, now Chugai, announced positive topline results from its Phase 3 clinical study of Filspari in Japanese patients with IgAN and plans to submit an NDA in Japan in 2026. Additionally, in February 2025, Travere announced completion of its Type C meeting with the FDA and in March 2025 submitted a supplemental New Drug Application (sNDA) seeking traditional approval of Filspari for focal segmental glomerulosclerosis (FSGS). The sNDA is based on existing data from the Phase 3 DUPLEX and Phase 2 DUET studies of Filspari. In January 2026, Travere announced that the FDA had extended the review of the sNDA with a new PDUFA target action date of April 13, 2026. The extension followed the submission of responses requested by the FDA to further characterize the clinical benefit of Filspari. The FDA determined that this constituted a Major Amendment to the sNDA and extended the action date accordingly. No additional information relating to the safety or manufacturing of Filspari has been requested by the FDA.

Ohtuvayre (Merck, Nuance)

We acquired a royalty on Merck’s Ohtuvayre (ensifentrine) through our acquisition of Vernalis in 2018 and acquired additional rights from Ohtuvayre inventors during the course of 2024 continuing through January 2025, bringing our royalty rate to 3% of global net sales. Verona originally developed Ohtuvayre before becoming acquired by Merck in October of 2025. Ohtuvayre is a first-in-class selective dual inhibitor of the enzymes phosphodiesterase 3 and phosphodiesterase 4 (“PDE3 and PDE4”) that combines bronchodilator and non-steroidal anti-inflammatory effects in one molecule. Ohtuvayre was approved by the FDA in June 2024 for the maintenance treatment of chronic obstructive pulmonary disease (“COPD”) in adult patients. Ohtuvayre is the first inhaled product with a novel mechanism of action approved for the maintenance treatment of COPD in adult patients in more than 20 years. Prior to its acquisition by Merck, Verona sublicensed the rights to develop and commercialize Ohtuvayre in Hong Kong, Macau, Taiwan, and mainland China to Nuance Pharma. In June 2025, Verona exercised its option to buy back the license granted to Nuance Pharma. Nuance Pharma has disputed the buy-back notice and requested that it be withdrawn.

Clinical Development of Ohtuvayre

Ohtuvayre is also in clinical development for additional territories and indications. In May 2025, Nuance announced that its Phase 3 trial evaluating ensifentrine for the maintenance treatment of COPD met its primary endpoint, as well as secondary endpoints demonstrating improvement in lung function. Merck is also currently conducting Phase 2 trials for indication expansion in non-cystic fibrosis bronchiectasis, as well as a fixed-dose combination of ensifentrine + Long-Acting Muscarinic Antagonist (LAMA) for maintenance treatment of COPD.

Rylaze (Jazz Pharmaceuticals)

In July 2021, Jazz announced the U.S. launch of Rylaze (asparaginase erwinia chrysanthemi (recombinant)-rywn), previously referred to as JZP458. Rylaze, is a recombinant erwinia asparaginase used as a component of a multi-agent chemotherapeutic regimen for the treatment of acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL) in adult and pediatric patients one month or older who have developed hypersensitivity to E. coli-derived asparaginase. In

September 2023, Jazz announced that the European Commission (EC) had granted marketing authorization for Rylaze, to be marketed as Enrylaze. Jazz began a rolling launch in the second half of 2023.

We are eligible to receive tiered low-single digit royalties based on worldwide net sales of Rylaze, Enrylaze and any products resulting from this collaboration.

Capvaxive (Merck)

Capvaxive, a 21 valent pneumococcal vaccine, also known as V116, was approved by the FDA in June 2024 for the prevention of invasive disease caused by Streptococcus pneumoniae serotypes 3, 6A, 7F, 8, 9N, 10A, 11A, 12F, 15A, 15C, 16F, 17F, 19A, 20A, 22F, 23A, 23B, 24F, 31, 33F, and 35B in adults 18 years of age and older. Capvaxive is the first pneumococcal conjugate vaccine specifically designed for adults, and its 21 covered serotypes account for approximately 85% of cases of invasive pneumococcal disease among individuals 50 and over, including 8 serotypes not covered by any other currently approved vaccines. Following the FDA approval, the US Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (“ACIP”) voted to update the adult age-based pneumococcal vaccination guidelines to recommend Capvaxive for pneumococcal vaccination in adults 50 years of age and older with certain health risks. Capvaxive utilizes the CRM197 vaccine carrier protein, which is produced using the patent-protected Pelican Expression Technology platform, which we acquired in October 2020 through our acquisition of Pfenex and spun out and merged with Primordial Genetics to form Primrose Bio in September 2023. The FDA approval of Capvaxive triggered a $2 million milestone payment to Ligand, and we are entitled to a low single-digit royalty on worldwide net sales.

Vaxneuvance (Merck)

Vaxneuvance, a 15-valent pneumococcal conjugate vaccine, also known as V114, was approved in the U.S. in July of 2021 for the prevention of invasive disease caused by Streptococcus pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F and 33F in adults 18 years of age and older, and subsequently in children 6 weeks through 17 years of age in June of 2022. Vaxneuvance was also approved in Europe in October 2022 for the prevention of invasive disease and pneumonia caused by Streptococcus pneumoniae in individuals 18 years and older and in infants, children and adolescents from 6 weeks to less than 18 years of age. Vaxneuvance utilizes CRM197 vaccine carrier protein, which is produced using the patent-protected Pelican Expression Technology platform, which we acquired in October 2020 through our acquisition of Pfenex. We are entitled to low single-digit royalties derived from net sales of Vaxneuvance.

Pneumosil (Serum Institute of India, SII)

SII began commercialization of its 10-valent pneumococcal conjugate vaccine, Pneumosil, which is produced using CRM197 made in the Pelican Expression Technology platform, in the second quarter of 2020. Pneumosil is designed primarily to help fight against pneumococcal pneumonia among children, with an advantage of targeting the most prevalent serotypes of the bacterium causing serious illness in developing countries. Pneumosil achieved WHO Prequalification in December 2019, allowing the product to be procured by United Nations agencies and Gavi, the Vaccine Alliance, and following the Indian Marketing Authorization in July 2020, SII announced commercial launch of the product in India in December 2020. We are entitled to a low-single digit royalty on net product sales of Pneumosil.

Teriparatide Injection Product (PF708) (Alvogen/Adalvo)

We acquired rights to the teriparatide injection product with the acquisition of Pfenex in October 2020. Teriparatide injection is a drug indicated for various uses including the treatment of osteoporosis in certain patients at high risk for fracture. Teriparatide injection was developed using our Pelican Expression Technology and was approved by the FDA in 2019 in accordance with the 505(b)(2) regulatory pathway, with FORTEO as the reference product. Our commercialization partner, Alvogen, launched the product in June 2020 in the United States.

Alvogen has exclusively licensed the rights to commercialize and manufacture the teriparatide injection product in the U.S., while Adalvo has the rights to commercialize in the E.U. and other territories outside the U.S. In accordance with our agreements with Alvogen, we are eligible to receive tiered gross profit sharing of between 25% and 40% of quarterly profit.

Evomela (Acrotech and CASI)

We supply Captisol to, and receive royalties from, Acrotech Biopharma for sales of Evomela in the United States, and CASI Pharmaceuticals for sales in China. Evomela is a Captisol-enabled melphalan IV formulation which is approved by the FDA for use in two indications:

•a high-dose conditioning treatment prior to autologous stem cell transplantation (“ASCT”) in patients with multiple myeloma; and

•for the palliative treatment of patients with multiple myeloma for whom oral therapy is not appropriate.

Under the terms of the license agreement, Acrotech Biopharma has marketing rights worldwide excluding China, and CASI Pharmaceuticals has marketing rights in China. We receive a 20% royalty on global net sales of the Captisol-enabled melphalan product and revenue from Captisol material sales. Acrotech and CASI’s obligation to pay royalties will expire at the end of the life of the relevant patents or when a competing product is launched, whichever is earlier, but in no event less than ten years from commercial launch. Our patents and applications relating to the Captisol component of melphalan are not expected to expire until 2033. As described herein, we have entered into a settlement agreement with Teva and Acrotech Biopharma (the holder of the NDA for Evomela) which will allow Teva to market a generic version of Evomela in the United States in 2026. Absent early termination, the agreement will terminate upon expiration of the obligation to pay royalties. In December 2024, Acrotech issued a termination process letter to CASI alleging the Company materially breached the license agreement and failed to cure such breach, thus terminating the license agreement. CASI can continue to distribute Evomela in China for a reasonable wind down period not to exceed 24 months.

Nexterone (Baxter)

We have a license agreement with Baxter, related to Nexterone, a Captisol-enabled formulation of amiodarone, which is marketed in the United States and Canada. We supply Captisol to Baxter for use in accordance with the terms of this license agreement and a separate supply agreement. Under the terms of the license agreement, we will continue to earn milestone payments, a low single digit royalty, and revenue from Captisol material sales. We will earn royalties on net sales of Nexterone through early 2033.

Zelsuvmi (Pelthos)

We have a license agreement with Pelthos for Zelsuvmi (berdazimer) topical gel, 10.3%, the first and only at-home treatment for molluscum contagiosum infections in adults and pediatric patients one year of age and older. Zelsuvmi was approved in the U.S. by the FDA in January 2024 and Pelthos commercially launched Zelsuvmi. After the completion of the Pelthos Transaction, Ligand earned a $5 million milestone payment from Pelthos following the commercial launch of Zelsuvmi in July 2025. Ligand is also entitled to a 13% royalty on worldwide sales of Zelsuvmi, and up to an additional $5 million in commercial sales milestones, pursuant to the terms of the definitive agreements for the Pelthos Transaction.

Tzield/Teizeild (Sanofi)

We acquired a royalty of less than 1% on net sales of Tzield through our acquisition of Tolerance Therapeutics (“Tolerance”) in the fourth quarter of 2023. Tzield is the first disease-modifying therapy to be approved in type 1 diabetes (“T1D”). It is a CD3-directed antibody indicated to delay the onset of Stage 3 T1D in adults and children aged 8 years and older with Stage 2 T1D. Tzield was granted Breakthrough Therapy Designation in 2019 and was approved by the FDA in November 2022 and was also approved in China by the National Medical Products Administration (NMPA) in September 2025. In January 2026, the European Commission approved teplizumab, branded in Europe as teizeild. Tzield/Teizeild is marketed by Sanofi, following its acquisition of Provention Bio, Inc., the developer of Tzield, in 2023 for $2.9 billion. Sanofi also announced data from Tzield’s PROTECT Phase 3 trial, which showed Tzield’s potential to slow the progression of Stage 3 T1D in newly diagnosed children and adolescents. Tzield met the study’s primary endpoint, significantly slowing the decline of C-peptide levels, compared to placebo.

In October 2025, Tzield was nominated for the FDA Commissioner's National Priority Review Voucher pilot program based on its potential to address a large unmet medical need. The FDA accepted the supplemental biologics license application (sBLA) for Tzield to delay the progression of stage 3 type 1 diabetes in adults and pediatric patients 8 years and older recently diagnosed with stage 3 T1D for expedited review. The program aims to shorten the review process from what normally takes 10-12 months to 1-2 months, while maintaining the FDA's rigorous safety and efficacy standards.

Under our agreement, we are entitled to receive royalties through December 1, 2032.

Other Key Partnered Programs

We have a highly diversified partnered pipeline of assets that we consider particularly noteworthy given the area of research or value of the license terms. We are eligible to receive milestone payments and royalties on these programs. This list does not include all of our partnered programs. In the case of Captisol-related programs, we are also eligible to receive revenue for the sale of Captisol material supply.

Qtorin rapamycin (Palvella)

We acquired economic rights to QtorinTM 3.9% rapamycin anhydrous gel (Qtorin rapamycin, formerly PTX-022) from Palvella in December 2018. Qtorin rapamycin is a novel, topical formulation of rapamycin currently in development for the treatment of Microcystic Lymphatic Malformations (“Microcystic LM”) and cutaneous venous malformations (“VMs”). The FDA has granted Breakthrough Therapy Designation, Fast Track Designation, and Orphan Designation to Qtorin rapamycin for the treatment of Microcystic LM. Microcystic LM is a chronically debilitating and lifelong genetic disease affecting an estimated more than 30,000 patients in the U.S. There are currently no FDA-approved treatments for Microcystic LM. In

February 2026, Palvella announced positive topline results from its Phase 3 SELVA study of Qtorin rapamycin for the treatment of microcystic LMs. The Phase 3 trial met its primary endpoint with statistically significant improvement on the Microcystic LM Investigator Global Assessment and achieved statistical significance on its pre-specified key secondary endpoint and all four secondary efficacy endpoints. Qtorin rapamycin was well tolerated, with no drug-related serious adverse events reported and systemic rapamycin levels below 2 ng/mL at all timepoints for all participants. 98% of participants who completed the efficacy evaluation period elected to continue to receive Qtorin rapamycin in the ongoing treatment extension period. An NDA submission is planned for the second half of 2026. Palvella announced positive topline results from its Phase 2 trial evaluating Qtorin rapamycin for the treatment of cutaneous VMs in December 2025. Based on the Phase 2 results, Palvella is expected to pursue near-term discussions with the FDA regarding the potential for Breakthrough Therapy Designation and a Phase 3 pivotal study. In September 2025, Palvella announced the expansion of its Qtorin rapamycin development program into clinically significant angiokeratomas. Palvella plans to meet with the FDA in the first half of 2026 to discuss the proposed design of a Phase 2 study to evaluate Qtorin rapamycin for the treatment of clinically significant angiokeratomas. Under the terms of our agreement with Palvella, we are entitled to milestones and a tiered royalty of 8.0% to 9.8% on any product containing Qtorin rapamycin.

D-Fi (Castle Creek)

In February 2025, we entered into a royalty financing agreement with Castle Creek Biosciences to support the Phase 3 clinical study of D-Fi (FCX-007), in patients with dystrophic epidermyolysis bullosa (DEB). D-Fi is an injectable autologous gene-modified cell therapy candidate for the treatment of DEB, a devastating, progressive, painful, and debilitating rare genetic skin disorder. DEB is caused by a mutation in the COL7A1 gene, leading to a deficiency of normal type VII collagen (COL7) protein, impairing the connection between the epidermis and the dermis. D-Fi is comprised of a patient’s own dermal fibroblasts, which are genetically modified completely ex vivo with a self-inactivating (SIN) lentiviral vector (LV) containing the COL7A1 gene to express COL7. D-Fi is locally administered by intradermal injection into wounds where the COL7 protein can support the formation of anchoring fibrils in the skin. D-Fi was granted Orphan Drug Rare Pediatric Disease, Fast Track, and Regenerative Medicine Advanced Therapy designations for the treatment of dystrophic epidermolysis bullosa (DEB) by the FDA. We are entitled to a mid-single-digit royalty on worldwide net sales of D-Fi.

AVIM Therapy and Virtue SAB (Orchestra BioMed)

On July 31, 2025, Ligand invested $25 million in strategic capital to fund Orchestra BioMed Holdings, Inc.'s (“Orchestra” or “Orchestra Biomed”) late-stage partnered cardiology programs, consisting of a $20 million cash payment paid at closing and an additional $5 million to purchase shares of Orchestra’s common stock in an equity private placement at the price of $2.75 per share (the price of Orchestra’s common stock at its last public offering). Ligand also agreed to fund an additional $15 million, subject to certain conditions precedent, at the nine-month anniversary of the transaction closing date. In exchange, Ligand received a low double-digit royalty on the first $100 million of Orchestra's annual revenues related to AVIM therapy and Virtue SAB programs in all indications. Ligand will also earn a mid-single-digit royalty on Orchestra's annual revenues exceeding $100 million related to AVIM therapy in the uncontrolled hypertension and increased cardiovascular risk indication and Virtue SAB in coronary artery disease indications. We also received warrants to purchase shares of Orchestra’s common stock. The transaction closed on August 4, 2025.

AVIM therapy is an investigational therapy compatible with standard dual-chamber pacemakers designed to substantially and persistently lower blood pressure. In addition to reducing blood pressure, clinical results using AVIM therapy demonstrate improvements in cardiac function and hemodynamics. The BACKBEAT global pivotal study will further evaluate the safety and efficacy of AVIM therapy in lowering blood pressure in patients who have systolic blood pressure above target despite anti-hypertensive medication and who are indicated for or have recently received a dual-chamber cardiac pacemaker. AVIM therapy has been granted Breakthrough Device Designation by the FDA for the treatment of uncontrolled hypertension in patients who have increased cardiovascular risk.

Virtue SAB is designed to deliver a proprietary extended-release formulation of sirolimus (SirolimusEFRTM) through a non-coated microporous AngioInfusionTM Balloon that protects the drug in transit to consistently deliver a large liquid dose, overcoming certain limitations of drug-coated balloons. SirolimusEFR delivered by Virtue SAB has been shown in published preclinical series involving hundreds of arterial deliveries to achieve sustained tissue levels well above the known therapeutic tissue concentration for inhibiting restenosis (1 ng/mg tissue) for the approximately 30-day critical healing period. Virtue SAB demonstrated positive three-year clinical data in coronary ISR in the SABRE study, a multi-center prospective, independent core-lab-adjudicated clinical study of 50 patients conducted in Europe. Virtue SAB has been granted Breakthrough Device Designation by the FDA for specific indications relating to coronary in-stent restenosis, coronary small vessel disease, and peripheral artery disease below-the-knee.

Botensilimab and Balstilimab (BOT/BAL) (Agenus)

In May 2024, we entered into the Agenus Agreement to support BOT/BAL clinical development. Botensilimab is an investigational multifunctional anti-CTLA-4 immune activator (antibody) designed to boost both innate and adaptive anti-tumor

immune responses. Its novel design leverages mechanisms of action to extend immunotherapy benefits to “cold” tumors which generally respond poorly to standard of care or are refractory to conventional PD-1/CTLA-4 therapies and investigational therapies. Botensilimab augments immune responses across a wide range of tumor types by priming and activating T cells, downregulating intratumoral regulatory T cells, activating myeloid cells and inducing long-term memory responses. Botensilimab alone, or in combination with Agenus’ investigational PD-1 antibody, balstilimab, has shown clinical responses across nine metastatic, late-line cancers. Approximately 1,200 patients have been treated with botensilimab and/or balstilimab in phase 1 and phase 2 clinical trials.

In 2025, the BOT/BAL combination demonstrated a two-year overall survival rate of 42% and median overall survival of 21 months in an expanded cohort of 123 patients with third-line or later microsatellite-stable (MSS) metastatic colorectal cancer (mCRC) without active liver metastases. Building on these results, Agenus, in collaboration with Canadian Cancer Trials Group (CCTG) has initiated the global BATTMAN Phase 3 trial evaluating BOT+BAL versus best supportive care (BSC) in patients with refractory, unresectable microsatellite stable (MSS)/mismatch repair proficient (pMMR) colorectal cancer. Sites have been activated and prepared to enroll approximately 800 patients across more than 100 sites in Canada, France, Australia, and New Zealand. Ligand is entitled to a 2.625% royalty on future global net sales generated by BOT/BAL pursuant to the Agenus Agreement. This rate may be adjusted depending on future events.

VK2809 (Viking)

Our partner, Viking, is developing VK2809, a novel selective thyroid hormone receptor beta (TR-beta) agonist with potential in metabolic dysfunction associated steatohepatitis (MASH). Viking completed a Phase 2b clinical trial (the VOYAGE study) in patients with MASH. At the 52-week mark, the drug reduced liver fat content by an average of 37% to 55% compared to baseline, with all treatment arms showing statistically significant improvements compared to placebo.

Under the terms of the agreement with Viking, we may be entitled to up to $225 million of development, regulatory and commercial milestones and a tiered royalty of 3.5% to 7.5% on potential future net sales of VK-2809. Viking is not currently advancing this program and has stated they intend to outlicense the program. Our TR-beta programs partnered with Viking are subject to CVR sharing, and a portion of the cash received will be paid out to CVR holders.

VK0214 (Viking)

VK0214, another novel, orally available, TR-beta agonist, is in development for the potential treatment of X-linked adrenoleukodystrophy (“X-ALD”). VK0214 has been evaluated in a Phase 1b clinical trial in patients with the adrenomyeloneuropathy (“AMN”) form of X-ALD.

Under the terms of the agreement with Viking, we may be entitled to up to $150 million of development, regulatory and commercial milestones and a tiered royalty of 3.5% to 7.5% on potential future net sales of VK-0214. Our TR-beta programs partnered with Viking are subject to CVR sharing, and a portion of the cash received will be paid out to CVR holders.

Lasofoxifene (LeonaBio, Henlius)

In December 2025, LeonaBio (f/k/a Athira Pharma, Inc.) acquired the global rights, excluding Asia and certain Middle Eastern countries, from Sermonix to develop and commercialize lasofoxifene, a Phase 3 oncology asset. The ongoing Phase 3 trial, previously conducted by Sermonix, was over 50% enrolled at the time of the transaction, with data expected in mid-2027. Lasofoxifene is a selective estrogen receptor modulator in development for the treatment of breast cancer, discovered through the research collaboration between Pfizer and Ligand. The ongoing Phase 3 ELAINE-3 clinical trial will assess the efficacy of lasofoxifene in combination with Eli Lilly and Company’s CDK4/6 inhibitor abemaciclib (Verzenio®) compared to fulvestrant and abemaciclib in pre- and post-menopausal subjects with locally advanced or metastatic ER+/HER2- breast cancer with an ESR1 mutation. Henlius entered into a strategic collaboration and exclusive license agreement with our former partner, Sermonix, to develop, manufacture and commercialize lasofoxifene in China. Henlius is currently participating in the Phase 3 ELAINE-3 multi-regional clinical trial in China.

Under the terms of our agreement with LeonaBio and Sermonix, we are entitled to receive potential regulatory and commercial milestone payments, as well as a tiered royalty of 6% to 10% on potential future net sales of lasofoxifene.

Full Portfolio Details

We have assembled one of the largest portfolios of biopharmaceutical assets in the industry which provides investors the opportunity to participate in the biotech industry while mitigating the industry’s usual inherent clinical binary risks. Our portfolio consists of assets which currently generate revenue through royalties on commercial products, as well as Captisol sales on commercial products. In addition to these assets, we have a substantial pipeline of development-stage assets that currently generate contractual payments through milestone and license fees with future potential for royalties and Captisol material sales for those programs under our Captisol technology.

Approved

Partner Name Program Indication Royalty Rate

Acrotech/CASI Evomela Multiple Myeloma 20%

Alvogen/Adalvo Teriparatide Osteoporosis 25-50% profit share

Arecor AT220 Undisclosed Undisclosed

Amgen/BeOne Medicines/Ono Kyprolis Multiple Myeloma 1.5%-3%

Baxter Nexterone Ventricular Arrhythmias Undisclosed

Eisai Fycompa Seizures Undisclosed

Elutia ECM portfolio Cardiac Device Low-single-digit

Fareva SA Noxafil-IV Fungal Infections Material sales only

Gilead Veklury COVID-19 Material sales only

Menarini Frovatriptan Migraine Undisclosed

Merck Vaxneuvance Invasive Pneumococcal Disease Vaccine Low-single-digit

Merck Capvaxive Invasive Pneumococcal Disease Vaccine Low-single-digit

Merck Ohtuvayre COPD Maintenance 3%

Novartis Mekinist Various Cancers Low-single-digit

Par Pharmaceutical, Inc. Posaconazole Fungal Infections Undisclosed

Pelthos Therapeutics Inc. Zelsuvmi Molluscum Contagiosum 13%

Pelthos Therapeutics Inc. Xepi Impetigo Low-single-digit

Pfizer Vfend-IV Fungal Infections Tiered low-single-digit

Recordati Qarziba High-risk Neuroblastoma Tiered mid-teens

Sanofi Tzield Stage 2 Type 1 Diabetes Less than 1%

Sedor/Lupin Ltd. Sesquient Seizures Undisclosed

SII Pneumosil Invasive Pneumococcal Disease Vaccine Low-single-digit

SII MenFive Invasive Meningococcal Disease Vaccine Low-single-digit

SQ Innovation Lasix ONYU Chronic Heart Failure Edema Low-single-digit

Travere/Vifor Pharma AG Filspari Primary Immunoglobulin A (IgA) Nephropathy 9%

Xi’an Xintong Xinshumu Hepatitis B 9%

Phase 3/Pivotal or Regulatory Submission Stage

Partner Name Program Indication Royalty Rate

Agenus Bot/Bal Microsatellite-Stable Colorectal Cancer 2.625%

Aldeyra Reproxalap Dry Eye Disease Material sales only

BendaRx Zafbena Hematologic Malignancies Material sales only

Curanex Pharmaceuticals Inc. CE-Topiramate Seizures Mid-single-digit

Nuance Pharma (Shanghai) Co. Ltd. Ohtuvayre (China) COPD Maintenance 3%

Ohara Pharmaceuticals Co., Ltd. JPH203 Advanced Biliary Tract Cancer Undisclosed

Palvella Qtorin rapamycin Microcystic Lymphatic Malformations 8%-9.8%

Sanofi Tzield Stage 3 Type 1 Diabetes Less than 1%

Travere Filspari Focal Segmental Glomerulosclerosis 9%

Phase 2

Partner Name Program Indication Royalty Rate

Corvus Ciforadenant Renal Cell Carcinoma Mid-single-digit to low-teens

Merck Ohtuvayre Non-cystic Fibrosis Bronchiectasis 3%

Merck Ohtuvayre + LAMA COPD 3%

Palvella Qtorin rapamycin Cutaneous Venus Malformations 8%-9.8%

Palvella Qtorin rapamycin Clinically Significant Angiokeratomas 8%-9.8%

Sanofi Efdoralprin alfa Alpha-1 Antitrypsin Deficiency Emphysema Undisclosed

Sato Pharmaceuticals Co, Ltd. Zelsuvmi (Japan) Molluscum Contagiosum Undisclosed

Viking VK2809 Metabolic Dysfunction-Associated Steatohepatitis (MASH) 3.5%-7.5%

Xi’an Xintong MB07133 Hepatocellular Carcinoma 6%

Phase 1

Partner Name Program Indication Royalty Rate

Arcellx, Inc. ACLX-001 Multiple Myeloma Undisclosed

Arcellx, Inc. ACLX-002 Acute Myeloid Leukemia Undisclosed

Beloteca, Inc. CE-Ziprasidone Schizophrenia Undisclosed

InvIOs APN401 Solid Tumors Undisclosed

Jupiter Biomedical Research, Inc. Viright Various Tumors Material sales only

Merck V118 Invasive Pneumococcal Disease Vaccine Undisclosed

Recordati Qarziba Ewing Sarcoma Tiered mid-teens

Viking VK0214 X-linked Adrenoleukodystrophy (X-ALD) Undisclosed

Manufacturing

We contract with a third-party manufacturer, Hovione, for Captisol production. Hovione operates FDA-inspected sites in the United States, Macau, Ireland and Portugal. Manufacturing operations for Captisol are performed primarily at Hovione’s Portugal and Ireland facilities. We believe we maintain adequate inventory of Captisol to meet our current partner needs and that our Captisol capacity will be sufficient to meet future partner needs.

In the event of a Captisol supply interruption, we are permitted to designate and, with Hovione’s assistance, qualify one or more alternate suppliers. If the supply interruption continues beyond a designated period, we may terminate our agreement with Hovione. In addition, if Hovione cannot supply our requirements of Captisol due to an uncured force majeure event, we may also obtain Captisol from a third-party and have previously identified such parties.

The original term of the agreement was through December 2024 and has been automatically renewed through December 2026. The agreement automatically renews for successive two-year renewal terms. Either party can give written notice of its intention to terminate the agreement no less than two years prior to the expiration of renewal term. In addition, either party may terminate the agreement for the uncured material breach or bankruptcy of the other party or an extended force majeure event. We may terminate the agreement for extended supply interruption, regulatory action related to Captisol or other specified events. We have ongoing minimum purchase commitments under our agreement with Hovione.

Competition

Some of the drugs we and our licensees and partners are developing may compete with existing therapies or other drugs in development by other companies. Furthermore, academic institutions, government agencies and other public and private organizations conducting research may seek patent protection with respect to potentially competing products or technologies and may establish collaborative arrangements with our competitors.

Our Captisol business may face competition from other suppliers of similar cyclodextrin excipients or other technologies that are aimed to increase solubility or stability of APIs.

Our competitive position also depends upon our ability to obtain patent protection or otherwise develop proprietary products or processes. For a discussion of the risks associated with competition, see below under “Item 1A. Risk Factors.”

Corporate and Governance Highlights

We are committed to policies and practices focused on environmental sustainability, positively impacting our social community and maintaining and cultivating good corporate governance. By focusing on such ESG policies and practices, we believe we can affect a meaningful and positive change in our community and maintain our open, collaborative corporate culture. We will continue our proactive shareholder and employee engagement in 2026. See www.ligand.com for information about our ESG policies and practices. However, note that the information contained on our website is not intended to be part of this filing.

Environmental, Health and Safety (“EHS”)

We are committed to providing a safe and healthy workplace, promoting environmental excellence in our communities, and complying with all relevant regulations and industry standards. We establish and monitor programs to reduce pollution, prevent injuries, and maintain compliance with applicable regulations. By focusing on such practices, we believe we can affect a meaningful, positive change in our community and maintain a healthy and safe environment. In early 2025, we completed our $2.6 million solar investment at Kansas University Innovation Park; made Environmental, Social and Governance (“ESG”) related charitable donations; and evolved numerous programs from our ESG-focused outreach committees. We expect to continue our effort and to refine our EHS policies and practices in 2026. More information on our EHS policies and initiatives is available on our website at www.ligand.com. However, note that the information contained on our website is not intended to be part of this filing.

Government Regulation

The research and development, manufacturing and marketing of pharmaceutical products are subject to regulation by numerous governmental authorities in the United States and other countries. We and our partners, depending on specific activities performed, are subject to these regulations. In the United States, pharmaceuticals are subject to regulation by both federal and various state authorities, including the FDA. In the U.S., the Federal Food, Drug and Cosmetic Act and the Public Health Service Act govern the research and development, testing, manufacture, quality, safety, efficacy, labeling, storage, record keeping, approval, advertising and promotion of pharmaceutical products. These activities are subject to additional regulations that apply at the state level. There are similar regulations in other countries as well. For both currently marketed products and products in development, failure to comply with applicable regulatory requirements at any time during the product development process, approval process or after approval, can, among other things, result in delays, the suspension of regulatory approvals, regulatory enforcement actions, as well as possible civil and criminal sanctions. In addition, changes in existing regulations could have a material adverse effect on us or our partners.

In particular, FDA approval is required before a drug or biological product may be marketed in the United States, and these products are also subject to other federal, state, and local statutes and regulations. The process required by the FDA before pharmaceutical products may be marketed in the United States generally involves the following:

•completion of extensive preclinical laboratory tests and preclinical animal studies, certain of which must be performed in accordance with Good Laboratory Practice regulations and other applicable requirements;

•submission to the FDA of an IND application, which must become effective before human clinical studies may begin;

•approval by an independent institutional review board or ethics committee at each clinical site before each clinical study may be initiated;

•performance of adequate and well-controlled human clinical studies in accordance with Good Clinical Practice (“GCP”) requirements to establish the safety and efficacy, or with respect to biologics, the safety, purity and potency of the product candidate for each proposed indication;

•preparation of and submission to the FDA of an NDA or BLA after completion of all pivotal clinical studies that include substantial evidence of safety, purity, and potency of the drug from analytical studies and from results of nonclinical testing and clinical trials;

•satisfactory completion of an FDA advisory committee review, where appropriate and if applicable;

•a determination by the FDA within 60 days of its receipt of an NDA or BLA to file the application for review;

•satisfactory completion of an FDA inspection of the manufacturing facility or facilities where the proposed product is produced to assess compliance with cGMP, and potential FDA inspection of nonclinical study and clinical trial sites that generated the data in support of the NDA or BLA to ensure compliance with GCP; and

•FDA review and approval of an NDA or BLA prior to any commercial marketing or sale of the drug in the United States.

Any products manufactured or distributed pursuant to FDA approvals are subject to pervasive and continuing regulation by the FDA, including, among other things, requirements relating to record-keeping, reporting of adverse experiences, periodic reporting, product sampling and distribution, and advertising and promotion of the product. There also are continuing user fee requirements, under which the FDA assesses an annual program fee for each product identified in an approved NDA or BLA. Drug and biologic manufacturers and their subcontractors are required to register their establishments with the FDA and some state agencies, and are subject to periodic unannounced inspections by the FDA and some state agencies for compliance with cGMPs, which among other things, impose certain procedural and documentation requirements upon BLA or NDA holders and any third-party manufacturers. FDA regulations also require investigation and correction of any deviations from cGMPs and impose reporting requirements upon manufacturers and their subcontractors. Accordingly, manufacturers must continue to expend time, money and effort in the area of production and quality control to maintain compliance with cGMPs and other aspects of regulatory compliance.

The FDA closely regulates the marketing, labeling, advertising and promotion of drug products and biologics. A company can make only those claims relating to safety and efficacy, purity and potency that are approved by the FDA and in accordance with the provisions of the approved label. The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses. Failure to comply with these requirements can result in, among other things, adverse publicity, warning letters, corrective advertising and potential civil and criminal penalties

The FDA may withdraw approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical studies to assess new safety risks; or imposition of distribution restrictions or other restrictions under a REMS program. Other potential consequences for non-compliance include, among other things:

•restrictions on the marketing or manufacturing of a product, complete withdrawal of the product from the market or product recalls;

•fines, warning letters or holds on post-approval clinical studies;

•refusal of the FDA to approve pending applications or supplements to approved applications, or suspension or revocation of existing product approvals;

•product seizure or detention, or refusal of the FDA to permit the import or export of products;

•consent decrees, corporate integrity agreements, debarment or exclusion from federal healthcare programs;

•mandated modification of promotional materials and labeling and the issuance of corrective information;

•the issuance of safety alerts, Dear Healthcare Provider letters, press releases and other communications containing warnings or other safety information about the product; or

•injunctions or the imposition of civil or criminal penalties.

For a discussion of the risks associated with government regulations, see below under “Item 1A. Risk Factors.”

Patents and Proprietary Rights

We believe that patents and other proprietary rights are important to our business. Our policy is to file patent applications to protect technology, inventions and improvements to our inventions that are considered important to the development of our business. We also rely upon trade secrets, know-how, continuing technological innovations and licensing opportunities to develop and maintain our competitive position.

Patents are issued or pending for the following key products or product families. The scope and type of patent protection provided by each patent family is defined by the claims in the various patents. Patent terms may vary by jurisdiction and depend on a number of factors including potential patent term adjustments, patent term extensions, and terminal disclaimers. For each product or product family, the patents and/or applications referred to are in force in at least the United States, and for most products and product families, the patents and/or applications are also in force in European jurisdictions, Japan and other jurisdictions.

Captisol

Patents and pending patent applications covering Captisol and methods of making Captisol are owned by us. The patents covering the Captisol product with the latest expiration date is expected to be in 2033 (see, e.g., U.S. Patent No. 9,493,582 (expires Feb. 27, 2033)). Other patent applications covering methods of making Captisol, if issued, potentially have terms to 2041. We also own several patents and pending patent applications covering drug products containing Captisol as a component. Globally, we own over 400 issued patents covering all of the foregoing Captisol compositions, methods and related technology.

Ten Captisol patents in several families are listed in the Orange Book in connection with one or more prescription drugs currently on the market. These Captisol-enabled drugs include Nexterone (Baxter), Kyprolis (Amgen), Noxafil (Merck), Evomela (Acrotech/CASI), Baxdela (Melinta) and Zulresso (Sage). These patents are listed in the table below, and each patent family containing these patents has pending and/or granted counterparts in Europe, China and Japan.

Orange Book-listed Captisol Patents

Country Patent No. Title Expiration (nominal) ‡

‡ Expiration dates are calculated as 20 years from the earliest nonprovisional filing date to which priority is claimed, and do not take into account disclaimers or extensions that are or may be available in these jurisdictions.

Subject to compliance with the terms of the respective agreements, our rights to receive royalty payments under our licenses with our exclusive licensors typically extend for the life of the patents covering such developments. For a discussion of the risks associated with patent and proprietary rights, see below under “Item 1A. Risk Factors.”

Nexterone

The United States patent listed in the Orange Book in connection with Nexterone is owned by CyDex is not expected to expire until March of 2029. In 2025, CyDex and Baxter filed suit against several related generic drug companies (PH Health Ltd., Par Health USA, Endo USA, Inc., Endo Operations Limited, and Endo, Inc.), asserting that their application to market a generic version of Nexterone infringed the Orange Book-listed patent. The defendants have filed an Answer. Discovery has started but a trial date has not yet been set.

Evomela

CyDex and Acrotech previously asserted patents listed in the Orange Book in connection with Evomela and settled each of those litigations. In 2025, CyDex and Acrotech filed suit against a generic drug company (Gland Pharma Limited) asserting that its application to market a generic version of Evomela infringed three of the Orange Book-listed patents. The three asserted patents are owned or co-owned by CyDex and the latest to expire of the three asserted patents is not expected to expire until May of 2030. An Answer has not yet been filed.

Kyprolis

Patents protecting Kyprolis include those owned by Amgen and those owned by us. The United States patent listed in the Orange Book relating to Kyprolis owned by Amgen with the latest expiration date is not expected to expire until 2029. Patents and applications owned by Ligand relating to the Captisol component of Kyprolis are not expected to expire until 2033. Amgen filed suit against several generic drug companies over their applications to make generic versions of Kyprolis. Several generics have settled with Amgen on confidential terms. However, it has been publicly reported that the U.S. launch date for at least Breckenridge Pharmaceuticals’ generic product will be on a date that is held as confidential in 2027 or sooner, depending on certain occurrences. One generic company, Cipla Limited/Cipla USA, Inc. chose not to settle the litigation with Amgen, and

proceeded to trial. The District Court upheld the validity of patent claims from three of the patents and the judgment was upheld on appeal.

Ligand UK Development Limited

Under the terms of our sale of Vernalis (R&D) Limited to HitGen in December 2020, Ligand retained a portfolio of fully-funded shots on goal, which now include S65487, a Bcl-2 inhibitor, and S64315, an Mcl-1 inhibitor for treatment of cancers, both of which are partnered with Servier in collaboration with Novartis. These programs and their IP are now owned by Ligand UK Development Limited, which has a worldwide patent portfolio of approximately 100 granted patents in over 40 countries. This patent portfolio is mature, with expected expiry dates up to 2033.

Pelican Expression Technology Platform

In connection with the merger of Pelican and Primrose, Pfenex assigned a substantial global patent portfolio consisting of numerous patents pending patent applications to Pelican, while retaining one patent family directed to methods of producing Erwinia asparaginase. Additionally, as part of the merger of Pelican and Primrose, Pfenex acquired a non-exclusive, worldwide, royalty-free, irrevocable, and fully sublicensable license to a broad portfolio of patents and pending patent applications which cover various aspects of the Pelican Expression Technology platform that are critical in helping support and retain contractual relationships including Jazz’s Rylaze, Merck’s Vaxneuvance and Capvaxive vaccines, Alvogen’s Teriparatide, and Serum Institute of India’s vaccine programs, including Pneumosil and MenFive vaccines, among others.

NITRICIL Platform

Through the 2023 Novan acquisition described herein, Ligand, through its then wholly owned subsidiary LNHC, acquired a robust IP portfolio that consists of over 45 U.S. patents, 120 non-U.S. patents, and 25 pending patent applications worldwide along with substantial know-how and trade secrets. On March 24, 2025, in connection with the Pelthos Transaction described herein, LNHC assigned this IP portfolio to Ligand, and Ligand entered into an exclusive license and sublicense agreement with LNHC, pursuant to which Ligand licensed to LNHC the intellectual property rights necessary to make, use, sell or offer to sell Zelsuvmi for the treatment of molluscum contagiosum in humans worldwide except for Japan. This IP portfolio provides material coverage for our platform technologies, licensed products and product candidates, in addition to Zelsuvmi, which was approved in the U.S. by the FDA on January 5, 2024. There are 14 issued U.S. patents covering Zelsuvmi which are listed in the Orange Book and which are expected to expire during the time period beginning in 2026 and ending in 2035. Upon the initial approval of Zelsuvmi, we applied for 1,280 days of patent term extension, or PTE, for the U.S. patent covering Zelsuvmi compositions. Assuming grant of the PTE application, the term of this patent may be extended from February 27, 2034, to August 30, 2037.

Apeiron

In connection with the acquisition of Apeiron in July 2024, we acquired a mature IP portfolio comprising of more than 300 patents worldwide. This IP portfolio supports a number of licensed products and product candidates, and comprises over 60 patents related to Qarziba with expected expiry dates between 2032 and 2034.

Human Capital Management

We recognize and take care of our employees by offering a wide range of competitive pay, recognition, and benefit programs. We are proud to provide our employees the opportunity to grow and advance as we invest in their education and career development. As of December 31, 2025, we have 47 full-time employees, of whom seven are involved directly in scientific research and development activities.

We rely on skilled, experienced, and innovative employees to conduct the operations of the Company. Our key human capital objectives include identifying, recruiting, retaining, incentivizing and integrating our existing and new employees. We frequently benchmark our compensation practices and benefits programs against those of comparable industries and in the geographic areas where our facilities are located. We believe that our compensation and employee benefits are competitive and allow us to attract and retain skilled labor throughout our organization. Our notable health, welfare and retirement benefits include:

•equity awards through our 2002 Stock Incentive Plan;

•subsidized health insurance;

•401(k) Plan with matching contributions;

•tuition assistance program; and

•paid time off.

We value diversity at all levels and continue to focus on extending our diversity and inclusion initiatives across our workforce. As of December 31, 2025, approximately 21% and 11% of our workforce are Asian and Hispanic, respectively. Additionally, 51% of our workforce is female and 49% is male. We believe that our business benefits from the different perspectives a diverse workforce brings. We embrace a flexible work environment, with team members working a combination of in office and virtually to fully support our partners and clients with the highest level of service, regardless of location and without disruption to our business operations. We believe it is important to bring our teams together to instill and reinforce our values-based culture, provide an opportunity to build meaningful connections with each other and the communities we serve as well as provide ongoing professional development and advancement opportunities. We gather feedback regularly and use this input to shape programs and address workforce needs. Our annual employee survey measures engagement across areas including belonging, learning and development, recognition, compensation and wellbeing. Insights from the survey are used to create action plans throughout the organization and to assess the alignment of our human capital management practices with our purpose and business strategy.

We strive to maintain an inclusive environment free from discrimination of any kind, including sexual or other discriminatory harassment. Our employees have multiple avenues available through which inappropriate behavior can be reported, including a confidential hotline. All reports of inappropriate behavior are promptly investigated with appropriate action taken to stop such behavior.

Investor Information

Financial and other information about us is available on our website at www.ligand.com. We make available on our website, without charge, copies of our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. You may obtain copies of these documents by visiting the SEC’s website at www.sec.gov. In addition, we use X (@Ligand_LGND) and our investor relations website as a means of disclosing material non-public information and for complying with our disclosure obligations under Regulation FD. Investors should monitor our X account and our website, in addition to following our press releases, SEC filings, public conference calls and webcasts. These website addresses and the information accessible through our X account are not intended to function as hyperlinks, and the information contained in our website and in the SEC’s website is not intended to be a part of this filing.

ITEM 1A. RISK FACTORS

The following is a summary description of some of the many risks we face in our business. You should carefully review these risks in evaluating our business and making an investment decision with respect to our securities, including the businesses of our subsidiaries. You should also consider the other information described in this report, including the information contained in our financial statements and the related notes and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.” Additional risks not presently known to us or that we currently deem immaterial also may impair our business.

Summary of Risks Related to our Business:

Our business is subject to numerous risks and uncertainties, including those described below. The principal risks and uncertainties affecting our business include, but are not limited to, the following:

Risks related to our business operations and reliance on third parties, including:

•Our ability to collect future revenue, including from sales of products from our collaboration partners, Captisol material sales and licensing relationships, and other collaboration relationships, is not guaranteed;

•Our ability to source Captisol from our sole supplier may be impacted by a supply interruption;

•The success of our partnered programs could be adversely affected by a change in our collaboration partners’ strategy or focus and/or development or regulatory hurdles, and market acceptance of such programs is not guaranteed;

•Risks related to the biopharmaceutical product market in general, including changes in growth rate, competition resulting from new technologies and developments, and other sales risks;

•Risks related to our ability to receive adequate information about the biopharmaceutical products we acquire and invest in and our underlying assumptions regarding future cash flow and revenue generation from such products; and

•Our collaboration partners may become insolvent.

Risks related to our intellectual property, including:

•Third-party intellectual property rights may prevent us or our partners from developing our potential products; our and our partners’ intellectual property may not prevent competition; and any intellectual property issues may be expensive and time consuming to resolve;

•Risks related to our ability to obtain and maintain sufficient intellectual property protection for our products, platforms and technology;

•Risks related to the validity, scope and enforceability of our and our collaboration partners’ patents and other intellectual property; and

•Other intellectual property-related risks, including the scope and validity of in-licenses from third parties, claims and disputes regarding patent infringement and other intellectual property rights that may be brought by third parties, changes in relevant patent and other intellectual property law, and the confidentiality of our trade secrets and other proprietary information.

Risks related to government regulation and legal proceedings, including:

•Market acceptance and sales of any approved product will depend significantly on the availability and adequacy of coverage and reimbursement from third-party payors and may be affected by existing and future healthcare reform measures;

•Regulatory approval of our product candidates can be time-consuming and unpredictable and is not guaranteed; and

•Risks related to our and our collaboration partners’ compliance with healthcare, environmental and other applicable laws and regulations.

Risks related to our strategic transactions, including:

•Difficulties from strategic acquisitions and other M&A transactions could adversely affect our stock price, operating results and results of operations; and

•We continue to have exposure to risks related to Pelthos due to our ongoing equity ownership and other investments in Pelthos, which could adversely affect our financial condition and results of operations.

Other risks and uncertainties affecting our business, including:

•Our operating results may fluctuate significantly, which makes our future operating results difficult to predict and could cause our operating results to fall below expectations or any guidance we may provide;

•Changes or modifications in financial accounting standards or tax laws may harm our results of operations;

•Risks related to our accounting methodologies and tax status;

•Cybersecurity incidents could compromise sensitive data and interrupt operations, leading to regulatory enforcement and reputational harm. We may be or become subject to certain data protection laws (e.g., the European Union General Data Protection Regulation and the UK equivalent of the same (collectively, “GDPR”) and the California Consumer Privacy Act of 2018 (as revised and amended by the California Privacy Rights Act, the “CCPA”)) and failure to comply with such laws could result in enforcement actions, fines and reputational harm;

•Ineffective development or deployment of artificial intelligence (“AI”) technologies could lead to errors or disruptions in our operations and evolving AI regulations could impose additional compliance burdens; and

•Other general risks and uncertainties affecting our business.

Risks Related to Our Business Operations and Reliance on Third Parties:

Future revenue based on Kyprolis, Qarziba, Filspari, Evomela, Teriparatide, Vaxneuvance, Ohtuvayre, Capvaxive and Rylaze, as well as royalties from our other partnered products, may be lower than expected.

A significant portion of our royalty revenue is based on sales of Kyprolis by Amgen, sales of Qarziba by Recordati, sales of Filspari by Travere, sales of Evomela by Acrotech Biopharma, sales of Teriparatide by Alvogen/Adalvo, sales of Vaxneuvance and Capvaxive by Merck, sales of Ohtuvayre by Verona Pharma, now a subsidiary of Merck, and sales of Rylaze by Jazz. Royalties, including payments from the foregoing partners, are expected to be a substantial portion of our ongoing revenues for the foreseeable future. Any setback that may occur with respect to any of our partners’ products, and in particular Kyprolis, could significantly impair our operating results and/or reduce our revenue and the market price of our stock. Setbacks for the products could include problems with shipping, distribution, manufacturing, product safety, marketing, government regulation or reimbursement, licenses and approvals, intellectual property rights, including failure by any of the foregoing

partners to enforce their respective intellectual property rights, competition with existing or new products and physician or patient acceptance of the products, as well as higher than expected total rebates, returns, discounts, or unfavorable exchange rates. These products also are or may become subject to generic competition. For example, we entered into a settlement agreement with Teva and Acrotech Biopharma (the holder of the NDA for Evomela) which will allow Teva to market a generic version of Evomela in the United States starting on June 1, 2026, or earlier under certain circumstances. The entry of generic competition for Evomela may materially and adversely affect the revenue we derive from Evomela sales. Also, Amgen previously settled patent litigation related to Kyprolis on confidential terms with several parties, but it was publicly reported that the U.S. launch date for at least Breckenridge Pharmaceuticals’ applicable generic product will be “on a date that is held as confidential in 2027 or sooner, depending on certain occurrences.”

Biopharmaceutical products are subject to sales risks.

Biopharmaceutical product sales may be lower than expected due to a number of reasons, including pricing pressures, insufficient demand, product competition, failure of clinical trials, lack of market acceptance, changes in the marketer’s strategic priorities, obsolescence, lack of acceptance by government healthcare programs or private insurance plans, loss of patent protection, government regulations or other factors, and development-stage product candidates may fail to reach the market. Unexpected side effects, safety or efficacy concerns can arise with respect to a product, leading to product recalls, withdrawals, declining sales or litigation. As a result, payments of our royalties may be reduced or ceased. In addition, these payments may be delayed, causing our near-term financial performance to be weaker than expected which could have an adverse effect on our business.

The royalty market may not grow at the same rate as it has in the past, or at all, and we may not be able to acquire sufficient royalties to sustain the growth of our business.

We have been able to grow our business over time by primarily acquiring royalties. However, we may not be able to identify and acquire a sufficient number of royalties, or royalties of sufficient scale, to invest the full amount of capital that may be available to us in the future, or at our targeted amount and rate of capital deployment, which could prevent us from executing our growth strategy and negatively impact our business. Changes in the royalty market, including its structure, participants growth rate, changes in preferred methods of financing and capital raising in the biopharmaceutical industry, reduced access to capital or higher cost of capital, or a reduction in the growth of the biopharmaceutical industry, could lead to diminished opportunities for us to acquire royalties, fewer royalties (or fewer royalties of significant scale) being available, or increased competition for royalties. Even if we continue to acquire royalties, they generally will not generate a meaningful return for a period of several years, if at all, due to transaction structures, circumstances relating to the underlying products or other factors. As a result, we may not be able to continue to acquire royalties or otherwise grow our business as we have done in the past, or at all.

Future revenue from sales of Captisol material to our license partners may be lower than expected.

Revenues from sales of Captisol material to our collaboration partners, including Amgen, represent approximately half of our royalty revenues. Any setback that may occur with respect to Captisol could significantly impair our operating results and/or reduce the market price of our stock. Setbacks for Captisol could include problems with shipping, distribution, manufacturing, product safety, marketing, government regulation or reimbursement, licenses and approvals, intellectual property rights, competition with existing or new products and physician or patient acceptance of the products using Captisol. In addition, we may continue to generate no revenue from Captisol sales related to remdesivir due to a number of factors, including alternative treatments for COVID-19 that have been or will be developed by other companies and the decrease in COVID-19 infections, in which case the commercial opportunity could be limited.

If products or product candidates incorporating Captisol material were to cause any unexpected adverse events, the perception of Captisol safety could be seriously harmed. If this were to occur, we may not be able to sell Captisol unless and until we are able to demonstrate that the adverse event was unrelated to Captisol, which we may not be able to do. Further, the FDA could require us to submit additional information for regulatory review or approval, including data from extensive safety testing or clinical testing of products using Captisol. This would be expensive and it may delay the marketing of Captisol-enabled products and receipt of revenue related to those products, which could significantly impair our operating results and/or reduce the market price of our stock.

A supply chain interruption may impact our ability to obtain Captisol material.

We obtain Captisol from Hovione, our third-party manufacturer, primarily at their facilities in Ireland and Portugal. If Hovione were to cease to be able, for any reason, to supply Captisol to us in the amounts we require, or decline to supply Captisol to us, we would be required to seek an alternative source, which could potentially take a considerable length of time and impact our revenue and customer relationships. In the event of a Captisol supply interruption, we are permitted to designate and, with Hovione’s assistance, qualify one or more alternate suppliers, although there is no assurance that we could do so

timely or at acceptable costs, if at all. In addition to manufacturing at Hovione’s facilities in Ireland and Portugal, we have processing capacity for Captisol in both the United States and England.

We maintain inventory of Captisol, which has a five-year shelf life, at three geographically dispersed storage locations in the United States and Europe. If we were to encounter problems maintaining our inventory, due to factors such as natural disasters, tariffs or trade restrictions at one or more of these locations, it could lead to supply interruptions. In addition, we rely on Hovione to expand manufacturing capacity of Captisol and any failure by Hovione to timely implement such increased capacity could adversely affect our ability to supply Captisol to our partners. While we believe we maintain adequate inventory of Captisol to meet our current partner needs, and our Captisol capacity will be sufficient to meet future partner needs, our estimates and projections for Captisol demand may not be correct and any supply interruptions could materially adversely impact our operating results.

The manufacture and distribution of a biopharmaceutical product may be interrupted by regulatory agencies or supplier deficiencies.

The manufacture of products generating our royalties is typically complex and is highly regulated. In particular, biopharmaceutical products are manufactured in specialized facilities that require the approval of, and ongoing regulation by,

the FDA in the United States and, if manufactured outside of the United States, both the FDA and non-U.S. regulatory agencies, such as the MHRA and the EMA. With respect to a product, to the extent that operational standards set by such agencies are not adhered to, manufacturing facilities may be closed or production interrupted until such time as any deficiencies noted by such agencies are remedied. Any such closure or interruption may interrupt, for an indefinite period of time, the manufacture and distribution of a product and therefore the cash flows from the related biopharmaceutical asset may be significantly less than expected.

In addition, manufacturers of a product may rely on third parties for selected aspects of product development, such as packaging or to supply bulk raw material used in the manufacture of such product. In the United States, the FDA requires that all suppliers of pharmaceutical bulk materials and all manufacturers of pharmaceuticals for sale in or from the United States adhere to the FDA’s current “Good Manufacturing Practice” regulations and guidelines and similar requirements that exist in jurisdictions outside the United States. Marketers of biopharmaceutical products generally rely on a small number of key, highly specialized suppliers, manufacturers and packagers. Any interruptions, however minimal, in the operation of these manufacturing and packaging facilities could adversely affect production and product sales and therefore adversely affect our business, financial condition or results of operations.

Future revenue from royalties on Captisol partnered products may be lower than expected.

We currently depend on our contractual arrangements with our partners and licensees to sell products using our Captisol technology. These agreements generally provide that our partners may terminate the agreements at will. If our partners discontinue sales of products using Captisol, fail to obtain regulatory approval for products using Captisol, fail to satisfy their obligations under their agreements with us, choose to utilize a competing product, or if we are unable to establish new licensing and marketing relationships then revenue from royalties on Captisol partnered products could be decreased and our financial results and growth prospects could be materially affected.

Further, under most of our Captisol out licenses, the amount of royalties we receive will be reduced or will cease when the relevant patent expires. Our low-chloride patents and foreign equivalents are not expected to expire until 2033, our high purity patents and foreign equivalents are not expected to expire until 2029 and our morphology patents and foreign equivalents are not expected to expire until 2026 in the United States; however, the initially filed patents relating to Captisol expired starting in 2010 in the United States and in 2016 in most countries outside the United States. If our other intellectual property rights are not sufficient to prevent a generic form of Captisol from coming to market, and if in such case our partners choose to terminate their agreements with us, our Captisol revenue may decrease significantly.

We rely heavily on collaboration relationships to generate milestone and royalty payments and our collaboration partners have significant discretion when deciding whether to pursue any development program, and any failure by our partners to successfully develop a product candidate or a termination or breach of any of the related agreements could reduce our milestone and license fee revenue, and potentially reduce future royalties.

Our strategy for developing and commercializing many of our product candidates includes entering into collaboration agreements, outlicenses, and development funding and royalty purchase agreements with corporate and other collaboration partners. These agreements give our collaboration partners significant discretion when deciding whether or not to pursue any development program. Our existing collaborations may not continue or be successful, and we may be unable to enter into future collaboration arrangements to develop and commercialize our unpartnered assets.

In addition, our collaboration partners may develop products, either alone or with others, that compete with the types of products they are developing with us (or that we are developing on our own). This would result in increased competition for our

or our partners’ programs. If product candidates are approved for marketing under our collaboration programs, revenues we receive will depend on the manufacturing, marketing and sales efforts of our collaboration partners, who generally retain commercialization rights under the collaboration agreements. Generally, our current collaboration partners also have the right to terminate their collaborations at will or under specified circumstances. If any of our collaboration partners breach (for example, by not making required payments when due, or at all) or terminate their agreements with us or otherwise fail to conduct their collaboration activities successfully, including due to insolvency events, ongoing product development under these agreements will be delayed or terminated. Disputes or litigation may also arise with our collaborators (with us and/or with one or more third parties), including those over ownership rights to intellectual property, know-how or technologies developed with our collaboration partners. Such disputes or litigation could adversely affect our rights to one or more of our product candidates. Any such dispute or litigation could delay, interrupt or terminate the collaboration research, development and commercialization of certain potential products, create uncertainty as to ownership rights of intellectual property, or could result in litigation or arbitration. The occurrence of any of these problems could be time-consuming and expensive and could adversely affect our business.

Our collaboration partners may change their strategy or the focus of their development and commercialization efforts with respect to our partnered programs, and the success of our partnered programs could be adversely affected.

If our collaboration partners terminate their collaborations with us or do not commit sufficient resources to the development, manufacture, marketing or distribution of our partnered programs, we could be required to devote additional resources to our partnered programs, seek new collaboration partners or abandon such partnered programs, all of which could reduce our revenues and otherwise have an adverse effect on our business.

In addition, biopharmaceutical development is inherently uncertain and very few therapeutic candidates ultimately progress through clinical development and receive approval for commercialization. If our partners do not receive regulatory approval for a sufficient number of therapeutic candidates originating from our partnerships, we may not be able to sustain our business model.

We may undertake strategic acquisitions of operating biopharmaceutical companies or acquire securities of biopharmaceutical companies. Our failure to realize the expected benefits of such acquisitions could adversely affect our business, financial condition or results of operations.

We may acquire companies with significant royalty assets or where we believe we could create significant synthetic royalties. These acquired or created royalty assets may not perform as we project. Moreover, the acquisition of operating biopharmaceutical companies will result in the assumption of, or exposure to, liabilities of the acquired business that are not inherent in our other royalty acquisitions, such as direct exposure to product liability claims, high fixed costs or an expansion of our operations and expense structure, thereby potentially decreasing our profitability. The diversion of our management’s attention and any delay or difficulties encountered in connection with any future acquisitions we may consummate could result in the disruption of our on-going business operations. Despite our business, financial and legal due diligence efforts, we ultimately may be unsuccessful in ascertaining or evaluating all risks associated with such acquisitions. Moreover, we may need to raise additional funds through public or private debt or equity financing to acquire any businesses or products, which may result in dilution for stockholders or the incurrence of indebtedness. As a result, our acquisition of operating biopharmaceutical companies could adversely affect our business, financial condition or results of operations.

We may seek to expand our market opportunity by acquiring securities issued by biopharmaceutical companies. Where we acquire equity securities as all or part of the consideration for business development activities, the value of those securities will fluctuate, and may depreciate. We will not control the companies in which we acquire securities, and as a result, we will have limited ability to determine management, operational decisions or policies. Further, such transactions may face risks and liabilities that due diligence efforts fail to discover, that are not disclosed to us, or that we inadequately assess. In addition, as a result of our activities, we may receive material non-public information about other companies. Where such information relates to a company whose equity securities we hold, we may be delayed or prevented from selling such securities when we would otherwise choose to do so, and such delay or prohibition may result in a loss or reduced gain on such securities.

Our product candidates, and the product candidates of our partners, face significant development and regulatory hurdles prior to partnering and/or marketing which could delay or prevent licensing, sales-based royalties and/or milestone revenue.

Before we or our partners obtain the approvals necessary to sell any of our unpartnered assets or partnered programs, we must show through preclinical studies and human testing that each potential product is safe and effective. We and/or our partners have a number of partnered programs and unpartnered assets moving toward or currently awaiting regulatory action. Failure to show any product’s safety and effectiveness could delay or prevent regulatory approval of a product and could, and has in the past, adversely affected our business. The product development and clinical trials process is complex and uncertain. For example, the results of preclinical studies and initial clinical trials may not necessarily predict the results from later large-scale clinical trials. In addition, clinical trials may not demonstrate a product’s safety and effectiveness to the satisfaction of the regulatory authorities. A number of companies have suffered significant setbacks in advanced clinical trials or in seeking

regulatory approvals, despite promising results in earlier trials. The FDA may also require additional clinical trials after regulatory approvals are received. Such additional trials may be expensive and time-consuming, and failure to successfully conduct those trials could jeopardize continued commercialization of a product.

The speed at which we and our partners complete our scientific studies and clinical trials depends on many factors, including, but not limited to, the ability to obtain adequate supplies of the products to be tested and patient enrollment. Patient enrollment is a function of many factors, including the size of the patient population, the proximity of patients to clinical sites, the eligibility criteria for the trial and other potential drug candidates being studied. Delays in patient enrollment for our or our partners’ trials may result in increased costs and longer development times. In addition, our partners have rights to control product development and clinical programs for products developed under our collaborations. As a result, these partners may conduct these programs more slowly or in a different manner than expected. Moreover, even if clinical trials are completed, we or our partners still may not apply for FDA or foreign regulatory approval in a timely manner, or the FDA or foreign regulatory authority still may not grant approval.

Our product candidate discovery, early-stage development, and product reformulation programs may require substantial additional capital to complete successfully. Our partners’ development programs may require substantial additional capital to complete successfully, arising from costs to: conduct research, preclinical testing and human studies; establish pilot scale and commercial scale manufacturing processes and facilities; and establish and develop quality control, regulatory, marketing, sales and administrative capabilities to support these programs. While we expect to fund our research and development activities from cash generated from operations to the extent possible, if we are unable to do so, we may need to complete additional equity or debt financings or seek other external means of financing. These financings could depress our stock price. If additional funds are required to support our operations and we are unable to obtain them on terms favorable to us, we may be required to cease or reduce further development or commercialization of our products, to sell some or all of our technology or assets or to merge with another entity.

New products and technologies of other companies may render some or all of our or our potential milestone and royalty providers’ product candidates noncompetitive or obsolete.

The biopharmaceutical industry is a highly competitive and rapidly evolving industry. New developments by others may render our potential milestone and royalty providers’ product candidates or technologies obsolete or uncompetitive. Current marketers of products may undertake these development efforts in order to improve their products or to avoid paying our royalty. In addition, as biopharmaceutical companies increasingly devote significant resources to innovate next-generation products and therapies using gene editing and new curative modalities, such as cell and gene therapy, products on which we have a milestone or royalty rights may become obsolete. Positive developments in connection with a potentially competing product may have an adverse impact on our future potential for receiving revenue derived from development milestones and royalties. For example, if another product is perceived to have a competitive advantage, or another product’s failure is perceived to increase the likelihood that our licensed product will fail, our potential milestone and royalty providers may halt development of product candidates in which we have an interest. Adverse competition, obsolescence or governmental and regulatory action or healthcare policy changes could significantly affect the revenues, including royalty-related revenues, of the products which generate our potential milestones and royalties. Finally, because many of the companies with which we do business also are in the biotechnology industry, the volatility of that industry can affect us indirectly as well as directly. The same factors that affect us directly also can adversely affect us indirectly by affecting the ability of our partners and others with whom we do business to meet their obligations to us and reduce our ability to realize the value of the consideration provided to us by these other companies in connection with their licensing of our products.

We face competition in acquiring existing “passive” royalties and locating suitable passive royalties to acquire.

There are a limited number of suitable and attractive opportunities to acquire high-quality royalties available in the market. Many potential royalty acquisition targets do not meet our criteria, and for those that do, we may face significant competition for these acquisitions from companies that market the products on which royalties are paid, financial institutions and others. This competition to acquire such royalties may increase. These competitors may be able to access lower cost capital, may be larger than us, may cause the price we pay for such royalty assets to increase, may have relationships that provide them access to opportunities before us, or may be willing to acquire royalties for lower projected returns than we are. Unsuccessful attempts to acquire new royalties because of transactions that do not meet our criteria or because of such competition could result in significant costs to us, could hurt our reputation and divert management and financial resources. Ligand may have to pursue different avenues such as project finance and special situations in order to create and capture royalty value.

Information available to us about the biopharmaceutical products underlying the royalties we purchase and invest in may be limited and, therefore, our ability to analyze each product and its potential future cash flow may be similarly limited.

We may have limited information concerning the products generating the royalties we are evaluating for acquisition. At times, the information we have regarding products following our acquisition of a royalty may be limited to the information that is available in the public domain. Therefore, there may be material information that relates to such products that we would like

to know but do not have and may not be able to obtain. For example, we do not always know the results of studies conducted by marketers of the products or others or the nature or amount of any complaints from doctors or users of such products. In addition, the market data that we obtain independently may also prove to be incomplete or incorrect. Due to these and other factors, the actual cash flow from a royalty may be significantly lower than our estimates.

A significant portion of our future income is dependent upon numerous royalty-specific assumptions and, if these assumptions prove not to be accurate, we may not achieve our expected rates of returns.

Our business model is based on multiple-year internal and external forecasts regarding product sales and numerous product-specific assumptions in connection with each royalty acquisition, including where we have limited information regarding the product, sales of our products and licenses to our technology. There can be no assurance that the assumptions underlying our financial models, including those regarding product sales or competition, patent expirations, exclusivity terms, license terms or license terminations for the products underlying our portfolio, products and technology, are accurate. These assumptions involve a significant element of subjective judgment and may be adversely affected by post-acquisition changes in market conditions and other factors affecting the underlying product or technology. The risks relating to these assumptions may be exacerbated for development-stage product candidates due to the uncertainties around their development, labeling, regulatory approval, commercialization timing, manufacturing and supply, competing products or related factors. With respect to our partnered programs, our assumptions regarding the financial stability or operational or marketing capabilities of the partner obligated to pay us royalties or license, milestone or other service payments, may also prove, and in the past have proven, to be incorrect. Due to these and other factors, the assets in our current portfolio or future assets, or our current or future products or technology, may not generate expected returns or returns in line with our historical financial performance or in the time periods we expect or at all, which could adversely affect our financial condition and results of operation.

The insolvency of any of our partners or third-parties who are developing or commercializing products to which we have economic rights could adversely affect our receipt of cash flows on the related milestones or royalties that we own.

If any of our partners or third-parties who are developing or commercializing products to which we have economic rights were to become insolvent and seek to reorganize under Chapter 11 of Title 11 of the U.S. Code, as amended, or the Bankruptcy Code, or liquidate under Chapter 7 of the Bankruptcy Code (or foreign equivalent), such event could delay or impede the payment of the amounts due to us under any license agreement, royalty purchase agreement or other contract under which we have acquired economic rights, pending a resolution of the insolvency proceeding. Unless we obtained a secured interest, any unpaid royalty payments under our license agreements with our partners and third-parties due for the period prior to the filing of the bankruptcy proceeding could become unsecured claims against such partner or third-party, which might not be paid in full or at all. The actual payment of such post-filing royalty payments could be delayed for a substantial period of time and might not be in the full amount due under such agreements. Given the nature of our royalty purchase agreements, royalty payments due to our partners or third-parties prior to or after a bankruptcy proceeding may not be subject to the insolvency proceeding and may be considered our property, meaning there is a reduced risk of payment delay and/or non-payment. Nevertheless, a partner or third-party or another party with an interest in an insolvency proceeding may attempt to recharacterize the royalty purchase agreement and claim that the royalty payments are property of the bankruptcy estate, in which case we would rely upon contractual protections related to such recharacterizations, which may not be respected in bankruptcy. In addition, certain of agreements with our partners or third-parties permit us to take a secured interest in the intellectual property underlying the licenses and royal purchase agreements and/or other collateral, which may improve our risk profile in an insolvency proceeding. However, even if such transactions are collateralized, we may be, or may become, under-secured in that collateral, or such collateral may lose value or may be liquidated at prices not sufficient to recover the full amount we are due pursuant to the terms of the agreements covering the particular assets, and we therefore may not be able to recuperate our capital expenditures associated with such transaction.

In some cases and depending on the terms of the agreement, we are not the licensor and instead are dependent on the licensor to enforce its right to royalties under an agreement with a licensee. In any bankruptcy proceeding, the licensor would be prevented by the automatic stay from taking any action to enforce its rights without the permission of the bankruptcy court. In addition, such partner or third-party could elect to reject the license agreement. Though this would prohibit such partner or third-party from continuing to market the applicable product, it would require the licensor to undertake a new effort to market the applicable product with another distributor. Such proceedings could adversely affect the ability of a partner or other payor to make payments with respect to a royalty, and could consequently adversely affect our business, financial condition or results of operations.

The commercial success of our product candidates will depend upon the degree of market acceptance by physicians, patients, third-party payers and others in the medical community.

The commercial success of our products, if approved for marketing, will depend in part on the medical community, patients and third-party payers accepting our product candidates as effective and safe. If these products do not achieve an

adequate level of acceptance, we may not generate significant product revenue and may not become profitable. The degree of market acceptance of our products, if approved for marketing, will depend on a number of factors, including:

•the safety and efficacy of the products, and advantages over alternative treatments;

•the labeling of any approved product;

•the prevalence and severity of any side effects, including any limitations or warnings contained in a product’s approved labeling;

•the prevalence of the disease or condition for which the product is approved;

•the emergence, and timing of market introduction, of competitive products;

•the effectiveness of our and our collaboration partners’ marketing strategy;

•obtaining and maintaining adequate pricing and reimbursement; and

•sufficient third-party insurance coverage or governmental reimbursement, which may depend on our ability to provide compelling evidence that a product meaningfully improves health outcomes to support such insurance coverage or reimbursement.

Even if a potential product displays a favorable efficacy and safety profile in preclinical studies and clinical trials, market acceptance of the product will not be known until after it is launched. Any failure to achieve market acceptance for our product candidates will harm our business, results and financial condition.

Furthermore, government agencies, as well as private organizations involved in healthcare, from time to time publish guidelines or recommendations to healthcare providers and patients. Such guidelines or recommendations can be very influential and may adversely affect product usage directly (for example, by recommending a decreased dosage of a product in conjunction with a concomitant therapy) or indirectly (for example, by recommending a competitive product over a product in which we have an ownership or royalty interest). Consequently, we do not know if physicians or patients will adopt or use products in which we have an ownership or royalty interest for their approved indications.

The success of our business depends on key members of our team.

We depend on the expertise, skill and network of business contacts of key members of our team, who evaluate, negotiate, structure, execute, monitor and service our assets and portfolio. Our future success depends to a significant extent on the continued service and coordination of our team. Our executives must devote substantially all of their business time to managing us, unless otherwise approved by the board of directors. Despite this, key members of our team may have other demands on their time, and we cannot assure you that they will continue to be actively involved in our business. The departure of any of these individuals or competing demands on their time could adversely affect our business, financial condition or results of operations.

Our key professionals have relationships with participants in the biopharmaceutical industry, financial institutions and other professionals, which we rely upon to source potential asset acquisition opportunities. If our key professionals fail to maintain such relationships, or to develop new relationships with other sources, we may not be able to grow our portfolio. In addition, we can offer no assurance that these relationships, even if maintained, will generate royalty acquisition opportunities for us in the future.

Risks Related to Intellectual Property:

Third-party intellectual property may prevent us or our partners from developing our potential products; our and our partners’ intellectual property may not prevent competition; and any intellectual property issues may be expensive and time consuming to resolve.

The manufacture, use or sale of our potential products or our licensees’ products or potential products may infringe the patent rights of others. If others obtain patents with conflicting claims, we may be required to obtain licenses to those patents or to develop or obtain alternative technology. We may not be able to obtain any such licenses on acceptable terms, or at all. Any failure to obtain such licenses could delay or prevent us from pursuing the development or commercialization of our potential products, platform and technology.

Generally, our success will depend on our ability and the ability of our partners to obtain and maintain patents and other intellectual property rights for our and their potential products and technologies. Our patent position is uncertain and involves complex legal and technical questions for which legal principles are unresolved. Even if we or our partners do obtain patents, such patents may not adequately protect the technology we own or have licensed.

We permit our partners to list our patents that cover their branded products in the Orange Book. If a third-party submits a new drug application (“NDA”) or abbreviated new drug application (“ANDA”) for a generic drug product that relies in whole

or in part on studies contained in our partner’s NDA for their branded product, the third-party will have the option to certify to the FDA that, in the opinion of that third-party, the patents listed in the Orange Book for our partner’s branded product are invalid, unenforceable, or will not be infringed by the manufacture, use or sale of the third-party’s generic drug product. A third-party certification that a new product will not infringe Orange Book-listed patents, or that such patents are invalid, is called a paragraph IV patent certification. If the third-party submits a paragraph IV patent certification to the FDA, a notice of the paragraph IV patent certification must be sent to the NDA owner and the owner of the patents that are subject to the paragraph IV patent certification notice once the third-party’s NDA or ANDA is accepted for filing by the FDA. A lawsuit may then be initiated to defend the patents identified in the notice. The filing of a patent infringement lawsuit within 45 days of the receipt of notice of a paragraph IV patent certification automatically prevents the FDA from approving the generic NDA or ANDA until the earlier of the expiration of a 30-month period, the expiration of the patents, the entry of a settlement order stating that the patents are invalid or not infringed, a decision in the infringement case that is favorable to the NDA or ANDA applicant, or such shorter or longer period as the court may order. If a patent infringement lawsuit is not initiated within the required 45-day period, the third-party’s NDA or ANDA will not be subject to the 30-month stay.

Several third parties have challenged, and additional third parties may challenge, the patents covering our partner’s branded products, including Kyprolis and Evomela, which could result in the invalidation or unenforceability of some or all of the relevant patent claims. We may from time to time become party to litigation or other proceedings as a result of Paragraph IV certifications. For example, as a result of the settlement of one such matter, Teva will be permitted to market a generic version of Evomela in the United States starting on June 1, 2026 or earlier under certain circumstances. The terms of the settlement agreement are otherwise confidential. Also, as noted above, Amgen previously settled patent litigation related to Kyprolis on confidential terms with several parties, but it has been publicly reported that the U.S. launch date for at least Breckenridge Pharmaceuticals’ applicable generic product will be “on a date that is held as confidential in 2027 or sooner, depending on certain occurrences.”

In addition, we cannot assure you that all of the potentially relevant prior art information that was or is deemed available to a person of skill in the relevant art prior to the priority date of the claimed invention-relating to our and our partners’ patents and patent applications has been found. If such prior art exists, it can invalidate a patent or prevent a patent from issuing from a pending patent application, and we or our partners may be subject to a third-party pre-issuance submission of prior art to the USPTO. Even if our patent applications do successfully issue and even if such patents cover our or our partner’s products or potential products, third parties may initiate litigation or opposition, interference, re-examination, post-grant review, inter partes review, nullification or derivation action in court or before patent offices, or similar proceedings challenging the validity, enforceability or scope of such patents, which may result in the patent claims being narrowed or invalidated, may allow third parties to commercialize our or our partners’ products and compete directly with us and our partners, without payment to us or our partners, or limit the duration of the patent protection of our and our partners’ technology and products.

In addition, similar to what other companies in our industry have experienced, we expect our competitors and others may have patents or may in the future obtain patents and claim that making, having made, using, selling, offering to sell or importing our technologies infringes these patents. Defense of infringement and other claims, regardless of their merit, would involve substantial litigation expense and would be a substantial diversion of management and employee resources from our business. Parties making claims against us may be able to sustain the costs of complex patent litigation more effectively than we can because they have substantially greater resources, or may be able to obtain injunctive or other relief, which could block our ability to develop, commercialize and sell products or services and could result in the award of substantial damages against us, including treble damages, attorney’s fees, costs and expenses if we are found to have willfully infringed. In the event of a successful claim of infringement against us, we may be required to pay damages and ongoing royalties and obtain one or more licenses from third parties, or be prohibited from selling certain products or services. As discussed above, we may not be able to obtain these licenses on acceptable or commercially reasonable terms, if at all, or these licenses may be non-exclusive, which could result in our competitors gaining access to the same intellectual property. In addition, we could encounter delays in product or service introductions while we attempt to develop alternative products or services to avoid infringing third-party patents or proprietary rights. Defense of any lawsuit or failure to obtain any of these licenses could prevent us from commercializing products or services, and the prohibition of sale of any of our technologies could materially affect our business and our ability to gain market acceptance for our technology.

Litigation or other proceedings to enforce or defend intellectual property rights are often very complex in nature, may be very expensive and time-consuming, may divert our management’s attention from our core business, and may result in unfavorable results that could adversely impact our ability to prevent third parties from competing with our partner’s products or technologies. Any adverse outcome of such litigation or other proceedings could result in one or more or our patents being held invalid or unenforceable, which could adversely affect our ability to successfully execute our business strategy and negatively impact our financial condition and results of operations. However, given the unpredictability inherent in litigation, we cannot predict or guarantee the outcome of these matters or any other litigation. Regardless of how these matters are ultimately resolved, these matters may be costly, time-consuming and distracting to our management, which could have a material adverse effect on our business. It may be necessary for us to pursue litigation or adversarial proceedings before the

patent office in order to enforce our patent and proprietary rights or to determine the scope, coverage and validity of the proprietary rights of others. The outcome of any such litigation might not be favorable to us, and even if we were to prevail, such litigation could result in substantial costs and diversion of resources and could have a material adverse effect on our business, operating results or financial condition.

In addition, periodic maintenance fees, renewal fees, annuity fees and various other governmental fees on patents and or applications will be due to the U.S. and various foreign patent offices at various points over the lifetime of our and our licensees’ patents and/or applications. We have systems in place to remind us to pay these fees, and we rely on our outside patent annuity service to pay these fees when due. Additionally, the U.S. and various foreign patent offices require compliance with a number of procedural, documentary, fee payment and other similar provisions during the patent application process. We engage reputable law firms and other third-party professionals to help us comply, and in many cases, an inadvertent lapse can be cured by payment of a late fee or by other means in accordance with rules applicable to the particular jurisdiction. However, there are situations in which noncompliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. If such an event were to occur, it could have a material adverse effect on our business.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. In addition, during the course of this kind of litigation, there could be public announcements of the results of hearings, motions or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could have a substantial adverse effect on the price of our common stock.

Any conflicts with the patent rights of others could significantly reduce the coverage of our patents or limit our ability to obtain meaningful patent protection. For example, our European patent related to Agglomerated forms of Captisol was limited during an opposition proceeding, and the rejection of our European patent application related to High Purity Captisol was upheld on appeal. In addition, any determination that our patent rights are invalid may result in early termination of our agreements with our license partners and could adversely affect our ability to enter into new license agreements. We also rely on unpatented trade secrets and know-how to protect and maintain our competitive position. We require our employees, consultants, licensees and others to sign confidentiality agreements when they begin their relationship with us. These agreements may be breached, and we may not have adequate remedies for any breach. In addition, our competitors may independently discover our trade secrets.

We may also need to initiate litigation, which could be time-consuming and expensive, to enforce our proprietary rights or to determine the scope and validity of others’ rights. If this occurs, a court may find our patents or those of our licensors invalid or may find that we have infringed on a competitor’s rights. In addition, if any of our competitors have filed patent applications in the United States prior to March 2013 which claim technology we also have invented, the United States Patent and Trademark Office may require us to participate in expensive interference proceedings to determine who has the right to a patent for the technology.

In addition, our agreements with some of our partners, suppliers or other entities with whom we do business require us to defend or indemnify these parties to the extent they become involved in infringement claims, including the types of claims described above. We could also voluntarily agree to defend or indemnify third parties in instances where we are not obligated to do so if we determine it would be important to our business relationships. If we are required or agree to defend or indemnify third parties in connection with any infringement claims, we could incur significant costs and expenses that could adversely affect our business, financial condition, results of operations and prospects. The occurrence of any of the foregoing problems could be time-consuming and expensive and could adversely affect our financial position, liquidity and results of operations.

If we are unable to obtain and maintain sufficient intellectual property protection for our products, platform and technology, or if the scope of the intellectual property protection obtained is not sufficiently broad, our competitors could develop and commercialize technologies or a platform similar or identical to ours, and our ability to successfully sell our platform and services may be impaired.

Our success depends in part on our ability to obtain and maintain adequate protection of the intellectual property we may own solely and jointly with others or otherwise have rights to, particularly patents, in the United States and in other countries with respect to our platform, our software and our technologies, without infringing the intellectual property rights of others.

We strive to protect and enhance the proprietary technologies that we believe are important to our business, including seeking patents intended to cover our platform and related technologies and uses thereof, as we deem appropriate. However, obtaining and enforcing patents in our industry is costly, time-consuming and complex, and we may fail to apply for patents on important products and technologies in a timely fashion or at all, or we may fail to apply for patents in potentially relevant jurisdictions. There can be no assurance that the claims of our patents (or any patent application that issues as a patent), will exclude others from making, using, importing, offering for sale, or selling products or services that are substantially similar to ours. We also rely on trade secrets to protect aspects of our business that are not amenable to, or that we do not consider

appropriate for, patent protection. In countries where we have not sought and do not seek patent protection, third parties may be able to manufacture and sell our technology without our permission, and we may not be able to stop them from doing so. We may not be able to file and prosecute all necessary or desirable patent applications, or maintain, enforce and license any patents that may issue from such patent applications, at a reasonable cost or in a timely manner. It is also possible that we will fail to identify patentable aspects of our research and development output before it is too late to obtain patent protection. We may not have the right to control the preparation, filing and prosecution of patent applications, or to maintain the rights to patents licensed to third parties. Therefore, these patents and applications may not be prosecuted and enforced in a manner consistent with the best interests of our business.

It is possible that none of our pending patent applications will result in issued patents in a timely fashion or at all, and even if patents are granted, they may not provide a basis for intellectual property protection of commercially viable products or services, may not provide us with any competitive advantages, or may be challenged and invalidated by third parties or deemed unenforceable by a court. It is possible that others will design around our current or future patented technologies. As a result, our owned and licensed patents and patent applications comprising our patent portfolio may not provide us with sufficient rights to exclude others from commercializing technology and products similar to any of our products, platform and technology.

LGND US Equity

LGND · 10-K · period ended 2025-12-31

Item 1. Business

ITEM 1A. RISK FACTORS

LGND US Equity☆

LGND · 10-K · period ended 2025-12-31

Item 1. Business

ITEM 1A. RISK FACTORS

LGND US Equity