SIGA TECHNOLOGIES INC (SIGA) Business

Item 1. Business

Overview

SIGA Technologies, Inc. is referred to throughout this report as “SIGA,” “the Company,” “we” or “us.”

We are a commercial-stage pharmaceutical company. The Company sells its lead product, TPOXX® (“oral TPOXX®,” also known as "tecovirimat," "Tecovirimat-SIGA," or "TEPOXX (tecovirimat)" in certain international markets), to the U.S. Government and international governments (including government affiliated entities). In certain international markets, the Company may sell TPOXX® through a distributor. Additionally, the Company sells the intravenous formulation of TPOXX® ("IV TPOXX®") to the U.S. Government.

TPOXX® is an antiviral drug for the treatment of human smallpox disease caused by variola virus. On July 13, 2018, the United States Food & Drug Administration (“FDA”) approved the oral formulation of TPOXX® for the treatment of smallpox. The Company has been delivering oral TPOXX® to the U.S. Strategic National Stockpile ("Strategic Stockpile") since 2013.

On May 18, 2022, the FDA approved IV TPOXX® for the treatment of smallpox.

In addition to being approved by the FDA, oral TPOXX® (tecovirimat) has received regulatory approval from the European Medicines Agency ("EMA"), Health Canada, the Medicines and Healthcare Products Regulatory Agency ("MHRA") of the United Kingdom, and the Japanese Pharmaceuticals and Medical Devices Agency ("PMDA"). The EMA, MHRA and PMDA approved oral TPOXX® for the treatment of smallpox, monkeypox ("mpox"), cowpox, and vaccinia complications following vaccination against smallpox. Health Canada approved TPOXX® for the treatment of smallpox.

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TPOXX® was authorized under “exceptional circumstances” by the EMA and the MHRA, under the brand name Tecovirimat-SIGA. These regulators granted marketing authorizations under “exceptional circumstances” because it was not possible to obtain complete efficacy and safety information about the product due to the rarity of smallpox and other orthopoxviruses and because ethical considerations prevented conducting the necessary clinical studies. The Tecovirimat-SIGA marketing authorizations under “exceptional circumstances” are subject to certain specific obligations to gather additional data post-approval to help confirm the product’s safety and efficacy. All “exceptional circumstances” marketing authorizations are subject to annual reassessments that consider whether data generated pursuant to the specific obligations continue to confirm its positive benefit-risk profile. These annual reassessments determine whether the product’s marketing authorization should be maintained, changed, suspended, or withdrawn based on its benefit-risk profile.

On July 24, 2025, the EMA’s Committee for Medicinal Products for Human Use (CHMP) closed its third annual reassessment for Tecovirimat-SIGA and initiated a referral procedure for the product following questions over its effectiveness in the treatment of mpox. These questions were raised following receipt of results from certain non-SIGA sponsored clinical trials evaluating tecovirimat as a potential mpox treatment including the PALM007 and STOMP clinical trials. In the referral procedure, CHMP reviewed all available data on the safety and efficacy of Tecovirimat-SIGA for all its authorized indications in order to make a recommendation to the European Commission whether the marketing authorization should be maintained, modified, suspended or withdrawn. The CHMP is expected to meet in March to issue its recommendation.  We expect the CHMP will confirm the positive benefit-risk balance of Tecovirimat-SIGA as a treatment for smallpox, cowpox, and vaccinia complications, and maintain those indications in the product label.  Regarding mpox, based on the results of the mpox clinical trials, we expect the CHMP will recommend withdrawal of the mpox indication. In the UK, Tecovirimat-SIGA is undergoing an annual reassessment by the MHRA.  This reassessment, which is ongoing, is substantially similar to the EMA’s annual reassessment process and could result in a similar outcome.

With respect to the regulatory approvals by the EMA, PMDA, MHRA and Health Canada, oral tecovirimat represents the same formulation approved by the FDA in July 2018 under the brand name TPOXX®.

In connection with a potential FDA label expansion of oral TPOXX® for an indication covering smallpox post-exposure prophylaxis (“PEP”), the Company has completed an immunogenicity trial and an expanded safety trial. The timing of a potential submission of a supplemental New Drug Application to the FDA (“Supplemental NDA”) for a smallpox PEP indication for oral TPOXX® will be based on the results of ongoing sample analyses from the immunogenicity trial; the Company is currently targeting a Supplemental NDA submission within the next twelve months.

Macroeconomic Environment

Future macroeconomic volatility, including changes to and uncertainty regarding tariffs and trade policies, could cause cost increases resulting in an adverse effect on the Company’s operating results. The Company’s supply chain was designed to lessen the impact of macroeconomic volatility such as through development of a U.S. domestic supply chain including U.S. production of API and finished product, and minimal reliance on ex-U.S. components for API and oral TPOXX®.

With respect to IV TPOXX®, tariff activity or other trading restrictions involving the U.S. and Europe may materially increase raw material costs for IV TPOXX® and, in turn, may materially increase IV TPOXX® overall manufacturing costs.

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Procurement Contracts with the U.S. Government

19C BARDA Contract

On September 10, 2018, the Company entered into a contract with the U.S. Biomedical Advanced Research and Development Authority ("BARDA") pursuant to which SIGA agreed to deliver up to 1,488,000 courses of oral TPOXX® to the Strategic Stockpile, and to manufacture and deliver to the Strategic Stockpile, or store as vendor-managed inventory, up to 212,000 courses of IV TPOXX®. In October 2023, the contract was modified so that a course of IV TPOXX® was redefined within the contract from being 14 vials to being 28 vials; as such, the 19C BARDA Contract currently specifies 106,000 courses of IV TPOXX® (for the same payment amount as originally specified). In addition to the delivery of TPOXX® courses, the contract includes funding from BARDA for a range of activities, including advanced development of IV TPOXX®, post-marketing activities for oral and IV TPOXX®, development of a pediatric formulation, support for manufacturing activities, and procurement activities. On April 8, 2025, total payments contemplated under the contract with BARDA were increased by $14.3 million to add funding for activities supporting manufacturing. On June 3, 2025, total payments contemplated under the contract with BARDA were increased by $13.2 million in connection with the development of the pediatric formulation of TPOXX®. As of December 31, 2025, the contract with BARDA (as amended, modified, or supplemented from time to time, the "19C BARDA Contract") contemplates up to approximately $630 million of payments, of which approximately $79.2 million of payments are included within the base period of performance, approximately $545.2 million of payments are related to exercised options and up to approximately $5.6 million of payments are currently specified as unexercised options. BARDA may choose in its sole discretion when, or whether, to exercise any of the unexercised options. The period of performance for options is up to ten years from the date of entry into the 19C BARDA Contract and such options could be exercised at any time during the contract term.

The base period of performance specifies potential payments of approximately $79.2 million for the following activities: payments of approximately $11.1 million for the delivery of approximately 35,700 courses of oral TPOXX® to the Strategic Stockpile; payments of $8.0 million for the manufacture of 10,000 courses (as currently defined within the contract as being 28 vials) of final drug product of IV TPOXX® ("IV FDP"), of which $3.2 million of payments are related to the manufacture of bulk drug substance ("IV BDS") to be used in the manufacture of IV FDP; payments of approximately $59.5 million to fund reimbursed activities; and payments of approximately $0.6 million for supportive procurement activities. As of December 31, 2025, the Company had received $11.1 million for the delivery of approximately 35,700 courses of oral TPOXX® to the Strategic Stockpile, $3.2 million for the manufacture of IV BDS, $4.8 million for the delivery of IV FDP to the Strategic Stockpile, and $31.2 million for other base period activities. IV BDS has been used for the manufacture of courses of IV FDP.

The options that have been exercised as of December 31, 2025, provide for payments up to approximately $545.2 million. As of December 31, 2025, there are exercised options for the following activities: payments up to $450.2 million for the manufacture and delivery of up to 1.5 million courses of oral TPOXX®; payments up to $76.8 million for the manufacture of courses of IV FDP; payments of up to approximately $3.6 million to fund post-marketing activities for IV TPOXX®; and payments of up to $14.6 million for funding of post-marketing activities for oral TPOXX®. As of December 31, 2025, a cumulative total of $450.2 million of oral TPOXX® has been delivered to the Strategic Stockpile and accepted; a cumulative total of $61.4 million of IV BDS or IV FDP has been either set aside in inventory or delivered to the Strategic Stockpile and accepted (IV BDS that has been set aside has been recorded as deferred revenue and will be recognized as revenue when the IV BDS is manufactured as IV FDP and delivered); and the Company has been cumulatively reimbursed $10.9 million in connection with post-marketing activities for oral and IV TPOXX®.

Unexercised options specify potential payments up to approximately $5.6 million in total (if all such options are exercised), all of which relates to supportive activities that we currently do not expect to be required.

The options related to IV TPOXX® were divided into two primary manufacturing steps. There were options related to the manufacture of bulk drug substance (“IV BDS Options”), and there were corresponding options (for the same number of IV courses) for the manufacture of final drug product (“IV FDP Options”). BARDA had the sole discretion to choose to exercise any, all, or none of these options. The 19C BARDA Contract included: three separate IV BDS Options, each providing for the bulk drug substance equivalent of 32,000 courses (as currently defined within the contract) of IV TPOXX®; and three separate IV FDP Options, each providing for 32,000 courses of final drug product of IV TPOXX®. BARDA had the sole discretion as to whether to simultaneously exercise IV BDS Options and IV FDP Options, or whether to exercise options at different points in time (or alternatively, to only exercise the IV BDS Option but not the IV FDP Option). To date, BARDA has exercised all three IV BDS options and all three IV FDP options. The Company estimates that sales of the IV formulation under this contract (under current terms), would have a gross margin (sales less cost of sales, as a percentage of sales) that is less than 40%.

U.S. Department of Defense Procurement Contracts

In 2024, the Company had sales of approximately $10 million with the U.S. Department of Defense ("DoD") (also known as the Department of War). Sales consisted mostly of delivery of oral TPOXX®, with a minor amount of IV TPOXX® delivered.

Over the past four years, the Company has received three procurement contracts from the DoD, totaling $28 million in value, mostly in connection with the manufacture and delivery of oral TPOXX®. All deliveries specified under these contracts have been fulfilled.

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International Sales Activity

In the year ended December 31, 2025, the Company had international sales of $5.8 million consisting of a delivery of oral TPOXX® to one country. The Company was the counterparty to the contract under which these international sales were made.

In the year ended December 31, 2024, the Company had international sales of $23.0 million consisting of deliveries of oral TPOXX® to 13 countries. For international sales in the first and second quarters, Meridian Medical Technologies ("Meridian") was the counterparty to contracts under which the sales were made (see discussion and definition below regarding International Promotion Agreement). For international sales in the third and fourth quarters, the Company was the counterparty to the contracts under which the sales were made.

Since the initiation of international sales in 2020, the Company has cumulatively recorded $137 million of oral TPOXX® international revenues.

International Promotion Agreement

Under the terms of the current International Promotion Agreement, which was amended on March 27, 2024, and effective June 1, 2024, and further amended on August 30, 2024, the Company has primary responsibility for the advertising, promotion and sale of oral TPOXX® in all geographic regions. Meridian has limited, non-exclusive rights to advertise, promote, offer for sale and sell oral TPOXX® in the European Economic Area, Australia, Japan, Switzerland, the United Kingdom and the Association of Southeast Asian Nations and its member states (collectively, the “Current Territory”). Meridian also performs non-promotional activities under specified contracts with third parties entered into prior to June 1, 2024, that provide for the sale of oral TPOXX® in the Current Territory. The International Promotion Agreement entitles Meridian to receive a fee equal to a high single digit percentage of collected proceeds (whether collected by Meridian or the Company), net of certain expenses, of sales of oral TPOXX® in the Current Territory in the field of use specified in the International Promotion Agreement. The International Promotion Agreement has a fixed term that expires on May 31, 2026, with no automatic renewal.

Under the terms of the original International Promotion Agreement ("Pre-amendment International Promotion Agreement"), which had an initial term that expired on May 31, 2024, Meridian had been granted exclusive rights to market, advertise, promote, offer for sale, or sell oral TPOXX® in a field of use specified in the International Promotion Agreement in all geographic regions except for the United States (the “Territory”), and Meridian agreed not to commercialize any competing product, as defined in the Pre-amendment International Promotion Agreement, in the specified field of use in the Territory. Under the Pre-amendment International Promotion Agreement, as well as the current International Promotion Agreement, SIGA has always retained ownership, intellectual property, distribution and supply rights and regulatory responsibilities in connection with TPOXX®, and, in the United States market, also retained sales and marketing rights with respect to oral TPOXX®. SIGA’s consent is required prior to the entry by Meridian into any sales arrangement pursuant to the International Promotion Agreement.

Sales to international customers pursuant to the Pre-amendment International Promotion Agreement were invoiced and collected by Meridian, and such collections were remitted, less Meridian's fees, to the Company under a quarterly process specified in the Pre-amendment International Promotion Agreement; and Meridian was entitled to a specified percentage of the collected proceeds of sales of oral TPOXX®, net of certain expenses, for calendar years in which customer collected amounts net of such expenses were less than or equal to a specified threshold, and to a higher specified percentage of such collected net proceeds for calendar years in which such net collected amounts exceeded the specified threshold. Subsequent to June 1, 2024, only specified procurement contracts for the Current Territory entered into prior to June 1, 2024, continue to involve Meridian invoicing and collecting proceeds, and retaining a fee pursuant to the International Promotion Agreement.

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Mpox

In connection with the 2022 response to a global mpox outbreak, a series of observational and randomized, placebo-controlled clinical trials were initiated to assess the safety and efficacy of TPOXX® in participants with mpox. The purpose of these randomized clinical trials was to seek to collect data on the potential benefits of using TPOXX® as an antiviral treatment for active mpox disease. As of December 31, 2025, three of the randomized, placebo-controlled clinical trials reported topline results: a randomized, placebo-controlled clinical trial in the Democratic Republic of the Congo ("DRC") known as PALM 007 (Tecovirimat for Treatment of Monkeypox Virus - NCT05559099), which was funded and sponsored by the National Institutes of Health's (NIH) National Institute of Allergy and Infectious Diseases (NIAID); the Study of Tecovirimat for Human Mpox Virus (STOMP) clinical trial (NCT05534984), which was a randomized, placebo-controlled, double-blind study also sponsored and funded by NIAID to evaluate the safety and efficacy of tecovirimat for the treatment of people with laboratory-confirmed or presumptive mpox disease that included enrollees from Argentina, Brazil, Japan, Mexico, Peru, Thailand, and the United States; and the UNITY clinical trial (Assessment of the Efficacy and Safety of Tecovirimat in Patients With Monkeypox Virus Disease - NCT NCT05597735), which was funded and sponsored by ANRS-Emerging Infectious Diseases, which included enrollees from Switzerland, Brazil, and Argentina. The PALM 007 study did not meet its primary endpoint of a statistically significant improvement in time to lesion resolution within 28 days post-randomization for patients in the DRC with mpox who received TPOXX® compared to patients who received placebo. Some improvement versus placebo was observed in patients receiving TPOXX® whose symptoms began five days or fewer before randomization and patients with severe or grave disease, defined by the World Health Organization (WHO) as having 100 or more skin lesions, however the significance of these data has not been established. Similarly, in the STOMP study, tecovirimat did not meet its primary endpoint of a statistically significant improvement in time to lesion resolution for adults with mild to moderate mpox and a low risk of developing severe disease. Additional analyses of subgroups, secondary and exploratory endpoints is ongoing in each of these studies. Topline data from the UNITY study, which was presented at a medical conference, also showed that the study did not meet its primary endpoint of a statistically significant improvement in time to lesion resolution for patients with mpox who received TPOXX® compared to patients who received placebo. In all three studies, TPOXX® exhibited a safety profile comparable to placebo. These safety results are consistent with prior studies and further support the strong safety profile that has been observed with tecovirimat over the past 15 years.

Two other randomized clinical trials, Platinum-CAN (Canada) and EPOXI (EU), which were started in response to the global mpox outbreak, are closed to enrollment and expected to yield similar results, given the design similarities across these trials.

Manufacturing

SIGA does not have a manufacturing infrastructure and does not intend to develop one for the manufacture of TPOXX®. SIGA relies on and uses third parties known as Contract Manufacturing Organizations (“CMOs”) to procure commercial raw materials and supplies, and to manufacture TPOXX®. SIGA's CMOs apply methods and controls in facilities that are used for manufacturing, processing, packaging, testing, analyzing and holding pharmaceuticals which conform to current good manufacturing practices (“cGMP”), the standard set by the FDA for manufacture and storage of pharmaceuticals intended for human use.

Oral TPOXX®:

For the manufacture of oral TPOXX®, the Company uses the following CMOs: W.R. Grace and Company (“Grace”), which acquired the assets of Albemarle's Fine Chemistry Services Business in 2021; Microsize, formerly known as Powdersize, LLC and renamed following a change of control transaction; Catalent Pharma Solutions LLC (“Catalent”); and Packaging Coordinators, LLC ("PCI").

SIGA has had manufacturing agreements with Grace and a predecessor owner (Albemarle) since 2011.  Pursuant to the current agreement with Grace, which was put in place in 2018 when Albemarle was the owner of the operations that provide services to SIGA, Grace manufactures, tests and supplies active pharmaceutical ingredient (“API”) for use in TPOXX®. The agreement provides that, during the term of the current agreement, SIGA was required to purchase 100% of its internal and external API requirements for TPOXX® from Grace until the later of (i) September 30, 2021 and (ii) such time as SIGA has purchased 12 metric tons of API from Grace under the agreement. As of December 31, 2025, SIGA has purchased more than 12 metric tons of API; as such, SIGA will purchase at least 70% of its internal and external API requirements for TPOXX® from Grace until the end of the term of the agreement (as described below), unless the Company receives an offer to purchase API at a price that Grace is unable to match, in which event SIGA will purchase at least 30% of its internal and external API requirements for TPOXX® from Grace until the Company has fulfilled its delivery obligations under the 19C BARDA Contract. There is no minimum amount of kilograms of API that must be used or acquired by SIGA. Pricing for API is at a fixed price per kilogram, subject to adjustment for increases in raw material costs and/or general manufacturing costs. On September 30, 2025, the contract term automatically renewed for a one-year term.

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Microsize micronizes and tests API for use in oral TPOXX®. The Company’s agreement with Microsize's predecessor was amended on January 11, 2019. The amended term ends on the tenth anniversary of the amendment date.

Catalent granulates, encapsulates, and tests oral TPOXX®. In addition, Catalent provides services related to commercial stability testing of drug product and preparation for tabulated stability and trend analysis for each time point. The Company’s agreement with Catalent had an initial term that ended on June 28, 2021. Thereafter, this agreement became subject to automatic three-year renewals. As such, until June 28, 2027, SIGA will purchase all of its requirements for bulk product for oral TPOXX® under the 19C BARDA Contract from Catalent.

PCI provides packaging services in connection with oral TPOXX®. Additionally, PCI has contracted with the Company to provide packaging services in connection with the intravenous formulation of TPOXX®. The Company’s agreement with PCI had an initial term that ended on March 1, 2022. Since March 2022, this agreement has automatically renewed for successive one-year periods.

Intravenous (IV) formulation of TPOXX®:

For the manufacture of IV TPOXX® under the BARDA Contract, the Company has agreed to use the following CMOs: Roquette America, Inc. (“Roquette”); Patheon Manufacturing Services LLC (“Patheon”); and PCI.

Roquette provides an excipient used in the manufacturing of IV TPOXX®. The Company's agreement with Roquette has no minimum amount of manufacturing services that must be used. The Company’s agreement with Roquette had an initial term that ended on December 31, 2023. Thereafter, this agreement automatically renews on a year-by-year basis unless either party provides four months’ notice of its desire to terminate the agreement prior to the expiration of the term. The Company did not provide notice nor receive notice of termination. As such, the agreement automatically extended on December 31, 2025 to December 31, 2026.

Patheon manufactures, tests and packages IV TPOXX®. SIGA agreed that Patheon was entitled to manufacture at least 80% of IV TPOXX® offered for sale by SIGA during the first three years of the agreement, provided Patheon adhered to reasonable manufacturing standards. Thereafter, the manufacturing percentage is mutually agreed upon by the parties. The Company’s agreement with Patheon has an initial term that ends on the later of: December 31, 2022 or, such date as all government contracts related to IV TPOXX® are terminated. As such, since the Company continues to have active government contracts related to IV TPOXX®, the contract term continues. At the end of the above mentioned contract term, this agreement automatically renews for two-year increments unless either party provides twelve months’ notice of its desire to terminate the agreement prior to the expiration of the term. In December 2025, the Company notified Patheon that the term would not be renewed, and the Company would not manufacture additional IV TPOXX® under this agreement once outstanding procurement orders under the BARDA Contract have been completed. The Company is currently working to transition the manufacture of IV TPOXX® to a new third party manufacturing site.

As noted above, PCI provides packaging services for IV TPOXX®. Grace provides the API used in manufacturing of the intravenous formulation.

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Market for Medical Countermeasures for Biological Threats

The market for medical countermeasures reflects continued awareness of the risks and threats of biological outbreaks, including such outbreaks related to global terror and biowarfare activity. The U.S. Government is the largest source of development and procurement funding for academic institutions and biopharmaceutical companies conducting medical countermeasure research or developing vaccines, anti-infectives and immunotherapies directed at potential agents of bioterror or biowarfare. For the U.S. Government's fiscal year ended September 30, 2025, the budget for annual spending by the U.S. Department of Health and Human Services ("HHS") for activities related to advanced development and procurement of medical countermeasures for biodefense-related biological threats to civilian populations was more than $2.5 billion.

We believe that potential markets for the sale of medical countermeasures include:

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General

With respect to U.S. Government contracts, we receive cash payments on a monthly basis as services are performed or goods are purchased. Amounts under contracts, including grant agreements, are not guaranteed because those contracts can be canceled at any time for reasons such as non-performance or convenience of the U.S. Government and, if canceled, we will not receive funds for additional work under the contracts. With respect to international government contracts, we receive cash payments based on the terms of the contract or, for certain contracts entered into by Meridian prior to June 1, 2024, the terms contained within the International Promotion Agreement with Meridian, under which Meridian collects payments from foreign governments.

Competition

The biotechnology and pharmaceutical industries are characterized by rapidly evolving technology and intense competition. Our current and potential competitors include many major pharmaceutical companies, many of which have significant financial, technical and marketing resources. Biotechnology and other pharmaceutical competitors in the medical countermeasure sector include, but are not limited to, Emergent BioSolutions Inc. and Bavarian Nordic A/S. Academic institutions, governmental agencies and other public and private research organizations are also conducting research activities and seeking patent protection and may commercialize products on their own or through joint ventures.

TPOXX® faces significant competition for government funding for both development and procurement of medical countermeasures for biological, chemical, radiological and nuclear threats, diagnostic testing systems, and other emergency preparedness countermeasures.

Our commercial opportunities could be reduced or eliminated if our competitors develop and commercialize products that are safer, more effective, have fewer side effects, are more convenient or are less expensive than products that we may develop. In addition, our commercial opportunities could be reduced or eliminated if the funding or procurement behavior of government customers substantially change. Furthermore, we may not be able to compete effectively if our product candidates do not satisfy governmental procurement requirements, particularly requirements of the U.S. Government with respect to medical countermeasure products.

Human Capital Resources

As of February 13, 2026, we had 49 full-time employees. None of our employees are covered by a collective bargaining agreement, and we consider our employee relations to be satisfactory.  Our human capital resources objectives include, as applicable, identifying, recruiting, retaining, incentivizing and integrating our existing and new employees, advisors and consultants with the overall goal of having an employee base that embraces teamwork and shares a focus for using each person’s individual skills, experience and expertise in order to develop and maximize the value of corporate assets, and achieve long-term revenue and earnings growth.

Intellectual Property and Proprietary Rights

An important element of SIGA’s business development activities involves the Company's ability to obtain and maintain patent and other intellectual property protection in the U.S. and the rest of the world for its proprietary technologies, drug targets, and potential products and to preserve its trade secrets. Because of the substantial length of time and expense associated with bringing potential products through the development and regulatory clearance processes to reach the marketplace, the pharmaceutical industry places considerable importance on obtaining patent and trade secret protection. The patent positions of pharmaceutical and biotechnology companies can be highly uncertain and involve complex legal and factual questions. No consistent policy regarding the breadth of claims allowed in biotechnology patents across various jurisdictions has emerged to date. Accordingly, SIGA cannot predict the type and extent of claims that will be allowed in pending patent applications.

SIGA also relies upon trade secret protection for its confidential and proprietary information. No assurance can be given that other companies will not independently develop substantially equivalent proprietary information and techniques or otherwise gain access to SIGA’s trade secrets or that SIGA can meaningfully protect its trade secrets.

SIGA exclusively owns its key patent portfolios, which relate to its leading drug product, TPOXX® (also known as ST-246, tecovirimat). As of February 20, 2026, the TPOXX® patent portfolio has seven patent families consisting of 26 U.S. utility patents, 101 issued foreign patents, one U.S. utility patent application, and 12 foreign patent applications.

The principal and material issued patents covering TPOXX® are described in the table below.

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*African Regional Intellectual Property Organization ("ARIPO") designated contracting states are as follows: Botswana, Gambia, Ghana, Kenya, Lesotho, Liberia, Malawi, Mozambique, Namibia, Sierra Leone, Sudan, Swaziland, Tanzania, Uganda, Zambia, and Zimbabwe.

^Organisation Africaine de la Propriété Intellectuelle ("OAPI") designated contracting states are as follows: Benin, Burkina Faso, Cameroon, the Central African Republic, Chad, DRC, Côte d’Ivoire, Equatorial Guinea, Gabon, Guinea, Guinea-Bissau, Mali, Mauritania, the Niger, Senegal, and Togo.

In addition to the patents listed in the above chart, the principal and material patent applications covering TPOXX® include patent filings in multiple jurisdictions, including the United States, Europe, Asia, and other commercially significant markets. We hold 13 patent applications currently pending with respect to various compositions of TPOXX®, methods of manufacturing, and methods of treatment. Expiration dates for pending patent applications, if granted, will fall between 2031 and 2037.

FDA regulations require that patented drugs be sold under brand names that comply with various regulations. SIGA must develop and make efforts to protect these brand names for each of its products in order to avoid product piracy and to secure exclusive rights to these brand names. SIGA may expend substantial funds in developing and securing rights to adequate brand names for our products. SIGA currently has proprietary trademark rights in SIGA®, TPOXX® and other brands used by us in the United States and certain foreign countries, but we may have to develop additional trademark rights in order to comply with regulatory requirements. SIGA may need to pursue different names and trademarks outside of the U.S. in light of native language and other jurisdictional considerations. SIGA considers securing adequate trademark rights to be important to its business.

Government Regulation

Regulatory Approval Process

Regulation by governmental authorities in the United States and other countries is a significant factor in the manufacture and marketing of any biopharmaceutical product that we may develop. The nature and the extent to which such regulations apply to us vary depending on the nature of each product. In particular, human therapeutic products are subject to rigorous pre-clinical and clinical testing and other approval procedures by the FDA and similar health authorities in foreign countries. Various federal statutes and regulations also govern or regulate the manufacturing, safety, labeling, storage, recordkeeping and marketing of such products. The process of obtaining these approvals and the subsequent compliance with appropriate federal and foreign statutes and regulations are complex and require expertise and the expenditure of substantial resources.

In order to test clinically, and to manufacture and market products for diagnostic or therapeutic use, a company must comply with mandatory procedures and safety standards established by the FDA and comparable agencies in foreign countries. Before beginning human clinical testing of a potential new drug in the United States, a company must file an Investigational New Drug ("IND") application and receive clearance from the FDA. An IND application is a summary of the pre-clinical studies that were conducted to characterize the drug, including toxicity and safety studies, information on the drug’s composition and the manufacturing and quality control procedures used to produce the drug, as well as a discussion of the human clinical studies that are being proposed to evaluate the safety and efficacy of the product.

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The pre-marketing clinical program required for approval by the FDA for a new drug typically involves a time-consuming and costly three-phase process. In Phase I, trials are conducted with a small number of healthy subjects to determine the early safety profile, the pattern of drug distribution, metabolism and elimination. In Phase II, trials are conducted with small groups of patients afflicted with a target disease in order to determine preliminary efficacy, optimal dosages and expanded evidence of safety. In Phase III, large scale, multi-center comparative trials, which may include both controlled and uncontrolled studies, are conducted with patients afflicted with a target disease in order to provide enough data for statistical proof of efficacy and safety required by the FDA and other authorities. Additional trials may be required to evaluate how a new drug interacts with other drugs as well as if the drug has any impact on cardio-vascular or other potential risks.

The FDA closely monitors the progress of each of the three phases of clinical testing and may, in its discretion, reevaluate, alter, suspend or terminate the testing based on the data that have been accumulated to that point and its assessment of the risk/benefit ratio to the patients involved in the testing. Estimates of the total time typically required for carrying out such clinical testing vary between two and 10 years. Upon completion of such clinical testing, a company typically submits a New Drug Application ("NDA") to the FDA that summarizes the results and observations of the drug during the clinical testing. Based on its review of the NDA, the FDA will decide whether to approve the drug and whether to impose any marketing restrictions or require additional post-approval clinical studies. This review process can be quite lengthy, and approval for the production and marketing of a new pharmaceutical product can require a number of years and substantial funding. There can be no assurance that any approval will be granted on a timely basis, if at all. In some circumstances, a new formulation of an approved product may be reviewed through a supplemental NDA process which relies in part on the prior approval of the initial formulation.

The FDA amended its regulations, effective June 30, 2002, to include the “Animal Rule” in circumstances that would permit the typical clinical testing regime to approve certain new drug and biological products used to reduce or prevent the toxicity of chemical, biological, radiological, or nuclear agents not otherwise naturally present for use in humans based on evidence of safety in healthy subjects and evidence of effectiveness derived only from appropriate animal studies and any additional supporting data. The FDA has indicated that approval for therapeutic use of TPOXX® for smallpox was determined under the “Animal Rule.”

Once a product is approved for sale, FDA regulations govern the manufacturing and marketing activities, and a post-marketing testing and surveillance program may be required to monitor a product’s usage and effects. Product approvals may be withdrawn if compliance with regulatory standards is not maintained. Many other countries in which products developed by us may be marketed impose similar regulatory processes.

FDA regulations also make available an alternative regulatory mechanism that may lead to use of the product under limited circumstances. The Emergency Use Authorization (“EUA”) authority allows the FDA Commissioner to strengthen the public health protections against biological, chemical, radiological and nuclear agents that may be used to attack the American people or the U.S. armed forces. Under this authority, the FDA Commissioner may allow medical countermeasures to be used in an emergency to diagnose, treat or prevent serious or life-threatening diseases or conditions caused by such agents when appropriate findings are made concerning the nature of the emergency, the availability of adequate and approved alternatives, and the quality of available data concerning the drug candidate under consideration for emergency use.

In addition to regulations in the United States, we are subject to a variety of foreign regulations governing clinical trials and commercial sales and distribution of our products. Whether or not we obtain FDA approval for a product, we must obtain approval by the comparable regulatory authorities of foreign countries or economic areas, such as the European Union (“EU”) and the United Kingdom ("UK"), before we may commence clinical trials or market products in those countries or areas. The approval process and requirements governing the conduct of clinical trials, product authorization, pricing and reimbursement vary greatly from place to place, and the time may be longer or shorter than that required for FDA approval.

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Under EU regulatory systems, a company may submit marketing authorization applications either under a centralized or decentralized procedure. The centralized procedure is compulsory for medicinal products produced by biotechnology or those medicinal products containing new active substances for specific indications such as the treatment of AIDS, cancer, neurodegenerative disorders, diabetes, viral diseases and designated orphan medicines, and optional for other medicines which are highly innovative. Under the centralized procedure, a marketing application is submitted to the European Medicines Agency ("EMA") where it will be evaluated by the Committee for Medicinal Products for Human Use and a favorable opinion typically results in the grant by the European Commission of a single marketing authorization that is valid for all EU Member States within 67 days of receipt of the opinion. The decentralized procedure provides for approval by one or more “concerned” member states based on an assessment of an application performed by one member state, known as the “reference” member state. Under the decentralized approval procedure, an applicant submits an application, or dossier, and related materials to the reference member state and concerned member states. The reference member state prepares a draft assessment and drafts of the related materials within 120 days after receipt of a valid application. Within 90 days of receiving the reference member state’s assessment report, each concerned member state must decide whether to approve the assessment report and related materials. If a member state does not recognize the marketing authorization, the disputed points are eventually referred to the European Commission, whose decision is binding on all member states.

The initial marketing authorization granted in the EU is valid for five years. Once renewed, the authorization is usually valid for an unlimited period unless the national competent authority or the EMA decides on justified grounds relating to pharmacovigilance, which could include exposure of an insufficient number of patients to the product concerned, to proceed with one additional five-year renewal. The renewal of a marketing authorization is subject to a re-evaluation of the risk-benefit balance of the product by the national competent authorities or the EMA.

In addition, products in the EU and the UK may be eligible for grant of marketing authorization under “exceptional circumstances” if an applicant for marketing authorization can demonstrate that comprehensive data on the efficacy and safety of the product under normal conditions of use cannot be provided due to certain specified objective and verifiable reasons such as the rarity of the target disease and because ethical considerations prevent the conduct of the necessary clinical studies. A marketing authorization granted under "exceptional circumstances" is valid for five years but is subject to annual reassessments that consider whether data generated pursuant to the specific obligations continue to confirm the positive benefit-risk profile of the product. These annual reassessments determine whether the product’s marketing authorization should be maintained, changed, suspended, or withdrawn based on its benefit-risk profile.

On January 10, 2022, the EMA approved SIGA’s Marketing Authorisation Application (MAA) for oral tecovirimat, the same formulation that was approved by the FDA in July 2018 under the brand name TPOXX®, under "exceptional circumstances." The EMA approval includes labeling for oral tecovirimat indicating its use for the treatment of smallpox, mpox, cowpox, and vaccinia complications following vaccination against smallpox. The MAA was filed under the centralized application process, which, upon approval, enables sales, including procurement for stockpiling, of oral tecovirimat in all EU Member States, as well as Norway, Iceland, and Liechtenstein.

The United Kingdom left the European Union on January 31, 2020 (commonly referred to as “Brexit”), with a transitional period that expired on December 31, 2020. The United Kingdom and the European Union entered into a trade agreement known as the Trade and Cooperation Agreement, which went into effect on January 1, 2021. On July 8, 2022, the United Kingdom’s Medicines and Healthcare products Regulatory Agency (“MHRA”) approved oral tecovirimat under "exceptional circumstances" for the treatment of smallpox, mpox, cowpox, and vaccinia complications following vaccination against smallpox in adults and children with a body weight of at least 13kg. Since the regulatory framework in the United Kingdom covering the quality, safety and efficacy of pharmaceutical products, clinical trials, marketing authorization, commercial sales and distribution of medicinal products is derived from EU Directives and Regulations, Brexit could materially impact the future regulatory regime which applies to products and the approval of other product candidates in the United Kingdom.

Legislation and Regulation Related to Bioterrorism Counteragents and Pandemic Preparedness

Because our drug candidates are intended for the treatment of diseases that may result from acts of bioterrorism or biowarfare or for pandemic preparedness, they may be subject to the specific legislation and regulation described below and elsewhere in this Annual Report on Form 10-K.

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Project BioShield

Project BioShield and related 2006 federal legislation provide procedures for biodefense-related procurement and awarding of research grants, making it easier for HHS to commit funds to countermeasure projects. Project BioShield provides alternative procedures under the Federal Acquisition Regulation, the general rubric for acquisition of goods and services by the U.S. Government, for procuring property or services used in performing, administering or supporting biomedical countermeasure research and development. In addition, if the Secretary of HHS deems that there is a pressing need, Project BioShield authorizes the Secretary of HHS to use an expedited award process, rather than the normal peer review process, for grants, contracts and cooperative agreements related to biomedical countermeasure research and development activity.

Under Project BioShield, the Secretary of HHS, with the concurrence of the Secretary of the U.S. Department of Homeland Security and upon the approval of the President, can contract to purchase unapproved countermeasures for the Strategic Stockpile in specified circumstances. The U.S. Congress is notified of a recommendation for a Strategic Stockpile purchase after Presidential approval. Project BioShield specifies that a company supplying the countermeasure to the Strategic Stockpile is paid on delivery of a substantial portion of the countermeasure. To be eligible for purchase under these provisions, the Secretary of HHS must determine that there are sufficient and satisfactory clinical results or research data, including data, if available, from pre-clinical and clinical trials, to support a reasonable conclusion that the countermeasure will qualify for approval or licensing within eight years. Project BioShield also allows the Secretary of HHS to authorize the emergency use of medical products that have not yet been approved by the FDA. To exercise this authority, the Secretary of HHS must conclude that:

Although this provision permits the Secretary of HHS to circumvent FDA approval (entirely, or in part) for procurement and use, its use in this manner would likely be limited to rare circumstances.

Public Readiness and Emergency Preparedness Act

The Public Readiness and Emergency Preparedness Act (the "PREP Act") provides immunity for manufacturers from claims under state or federal law for “loss” arising out of the administration or use of a “covered countermeasure” in the United States. However, injured persons may still bring a suit for “willful misconduct” against the manufacturer under some circumstances. “Covered countermeasures” include security countermeasures and “qualified pandemic or epidemic products,” including products intended to diagnose or treat pandemic or epidemic disease, as well as treatments intended to address conditions caused by such products. For these immunities to apply, the Secretary of HHS must issue a declaration in cases of public health emergency or “credible risk” of a future public health emergency. Since 2007, the Secretary of HHS has issued twelve declarations under the PREP Act to protect from liability countermeasures that are necessary to prepare the nation for potential pandemics or epidemics, including a declaration on October 10, 2008 that provides immunity from tort liability as it relates to smallpox. The PREP Act Declaration for smallpox countermeasures was amended by the Secretary of HHS in 2022 to emphasize that it covers mpox virus, add qualified persons to administer vaccines and therapeutics to address the current public health emergency caused by the 2022 outbreak of mpox cases and the risk of future public health threats arising from orthopoxviruses, and to extend protection from December 31, 2022 to December 31, 2032.

Foreign Regulation

As noted above, in addition to regulations in the United States, we might be subject to a variety of foreign regulations governing clinical trials and commercial sales and distribution of our drug candidates. Regardless of any FDA approval of a product, we may have to obtain approval of that product by the comparable regulatory authorities of foreign countries before we can commence clinical trials or marketing of the product in those countries. The actual time required to obtain clearance to market a product in a particular foreign jurisdiction varies substantially, based upon the type, complexity and novelty of the pharmaceutical drug candidate, the specific requirements of that jurisdiction, and in some countries whether the FDA has previously approved the drug for marketing. The requirements governing the conduct of clinical trials, marketing authorization, pricing and reimbursement vary from country to country. Certain foreign jurisdictions, including the European Union, United Kingdom and Canada, have adopted certain biodefense-specific regulations akin to those available in the United States such as a procedure similar to the “Animal Rule” promulgated by the FDA for review and potential approval of biodefense products.

Regulations Regarding Government Contracting

The status of an organization as a government contractor in the United States and elsewhere means that the organization is also subject to various statutes and regulations, including the Federal Acquisition Regulation, which governs the procurement of goods and services by agencies of the United States. These governing statutes and regulations can impose stricter penalties than those normally applicable to commercial contracts, such as criminal and civil damages liability and suspension and debarment from future government contracting. In addition, pursuant to various statutes and regulations, government contracts can be subject to unilateral termination or modification by the government for convenience in the United States and elsewhere, detailed auditing requirements, statutorily controlled pricing, sourcing and subcontracting restrictions and statutorily mandated processes for adjudicating contract disputes.

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Availability of Reports and Other Information

Our internet address is www.siga.com. Our investor relations website is located at https://investor.siga.com. We make available free of charge on our investor relations website under “Financials” our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, proxy and information statements, our directors’ and officers’ Section 16 reports and any amendments to those reports as soon as reasonably practicable after filing or furnishing such materials to the SEC. They are also available for free on the SEC’s website at www.sec.gov.

We use 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 such website, in addition to following our press releases, SEC filings and public conference calls and webcasts. Information relating to our corporate governance is also included on our investor relations website, including copies of our Code of Ethics and Business Conduct, Corporate Governance Guidelines, and the charters of the committees of our Board of Directors. The information in or accessible through the SEC and our website are not incorporated into, and are not considered part of, this filing.