HALOZYME THERAPEUTICS INC

There have been no material changes to the risk factors set forth under Part I, Item 1A. “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2024 other than the risks discussed below.

Risks Related To Our Business

Workforce reduction at federal agencies and changes in United States trade policy, including recently announced tariffs and potential countermeasures by trading partners, could delay regulatory approval and increase our or our partners’ costs, disrupt global supply chains and have a material adverse impact on our business, financial condition, and results of operations.

The current federal government administration has increased, and has indicated a willingness to continue to increase, the use of tariffs by the United States to accomplish certain policy goals. Such tariffs and any countermeasures by the United States’ trading partners could increase the cost of raw materials, components and finished goods necessary for our or our partners’ operations, disrupt global supply chains, create additional operational challenges and cause widespread uncertainty in the financial markets. Further, it is possible the administration’s trade policy changes directly impacting the biopharmaceutical industry and related uncertainty about such policy changes could increase volatility in the market valuation of companies in the healthcare industry. Because of these dynamics, we cannot predict the impact of any future changes to international trading relationships or the ultimate impact recently adopted tariff policies will have on our business. Such changes in tariffs and trade regulations could have a material adverse effect on our financial condition, results of operations and cash flows. Additionally, recent widespread reductions in workforce at federal health agencies, including the FDA, could have a negative impact on the speed with which our products or devices and our partners’ products are reviewed and approved for commercialization.

We may be required to initiate or defend against legal proceedings related to intellectual property rights, which may result in substantial expense, delay and/or cessation of certain development and commercialization of our products.

We primarily rely on patents to protect our intellectual property rights. The strength of this protection, however, is uncertain. For example, it is not certain that:

•we will be able to obtain patent protection for our products and technologies;

•the scope of any of our issued patents will be sufficient to provide commercially significant exclusivity for our products and technologies;

•others will not independently develop similar or alternative technologies or duplicate our technologies and obtain patent protection before we do; and

•any of our issued patents, or patent pending applications that result in issued patents, will be held valid, enforceable and infringed in the event the patents are asserted against others.

We currently own or license patents in a portfolio and also have pending patent applications applicable to rHuPH20 and other proprietary materials. There can be no assurance that our existing patents, or any patents issued to us as a result of our pending patent applications, will provide a basis for commercially viable products, will provide us with any competitive advantages, or will not face third-party challenges or be the subject of further proceedings limiting their scope or enforceability. Any weaknesses or limitations in our patent portfolio could have a material adverse effect on our business and financial condition. In addition, if our pending patent applications do not result in issued patents, or result in issued patents with narrow or limited claims, this could result in us having no or limited protection against generic or biosimilar competition against our product candidates which would have a material adverse effect on our business and financial condition.

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We may be required to initiate or defend against legal proceedings related to our intellectual property rights which may be time-consuming and result in substantial litigation expense. For example, in April 2025 we filed a patent infringement lawsuit against Merck Sharp & Dohme Corp. (“Merck”) in the U.S. District Court in New Jersey alleging that Merck is using Halozyme’s patented MDASE™ subcutaneous drug delivery technology to develop Subcutaneous (“SC”) Keytruda. We are seeking damages and injunctive relief to stop Merck’s infringement of Halozyme’s MDASE™ intellectual property. Patent infringement litigation can be costly, take a long period of time to resolve and involves uncertainties beyond our control. We can offer no assurance as to developments related to the patent infringement litigation, the outcome of the litigation or any remedies that could be awarded in connection with the litigation.

We or our partners may become involved in interference proceedings in the U.S. Patent and Trademark Office, or other proceedings in other jurisdictions, to determine the priority, validity or enforceability of our patents or our partners’ patents related to our collaborations. For example, as a result of two such proceedings, in March 2023 and October 2024 the Opposition Division of the European Patent Office revoked two of Janssen’s co-formulation patents for DARZALEX® (daratumumab) SC. Failure to overturn a first instance adverse decision on appeal, if available, could result in permanent loss of the contested patent rights. In addition, costly litigation could be necessary to protect our patent position. Successful challenges to the priority, validity or enforceability of our or our partners’ patents could have a material adverse effect on our business and financial condition.

We also rely on trade secrets, unpatented proprietary know-how and continuing technological innovation that we seek to protect with confidentiality agreements with employees, consultants and others with whom we discuss our business. Disputes may arise concerning the ownership of intellectual property or the applicability or enforceability of agreements covering these rights, and we might not be able to resolve these disputes in our favor.

We also rely on trademarks to protect the names of our products (e.g. Hylenex recombinant). We may not be able to obtain trademark protection for any proposed product names we select. In addition, product names for pharmaceutical products must be approved by health regulatory authorities such as the FDA in addition to meeting the legal standards required for trademark protection and product names we propose may not be timely approved by regulatory agencies which may delay product launch. In addition, our trademarks may be challenged by others. If we enforce our trademarks against third parties, such enforcement proceedings may be expensive.

In addition to protecting our own intellectual property rights, third parties may assert patent, trademark or copyright infringement or other intellectual property claims against us. If we become involved in any intellectual property litigation, we may be required to pay substantial damages, including but not limited to treble damages, attorneys’ fees and costs, for past infringement if it is ultimately determined that our products infringe a third-party’s intellectual property rights. Even if infringement claims against us are without merit, defending a lawsuit takes significant time, may be expensive and may divert management’s attention from other business concerns. Further, in the case of an injunction, we could be stopped from developing, manufacturing or selling our products until we obtain a license from the owner of the relevant technology or other intellectual property rights. If such a license is available at all, it may require us to pay royalties or other fees.