AGENUS INC

Item 1. Legal Proceedings

On March 24, 2026, the U.S. District Court for the District of Massachusetts (the "Court") granted the Company's motion to dismiss the putative securities class action captioned In re Agenus Inc. Securities Litigation, No. 1:24-cv-12299, in its entirety, ruling in favor of the Company and the individual defendants, and denied the lead plaintiff's request for leave to amend his complaint. The action was originally filed in September 2024 against the Company and certain of its executives and directors. The amended complaint, filed February 7, 2025 by the court-appointed lead plaintiff, alleged that Agenus, three of its current officers, and one member of its advisory board violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended, and Rule 10b-5 thereunder, by making false and misleading statements and omissions of material fact related to the efficacy and commercial prospects of BOT and BAL. The lead plaintiff sought to represent all persons who purchased or otherwise acquired Agenus securities between January 23, 2023 and July 17, 2024, and sought damages, interest, and an award of costs, including attorneys' fees.

The lead plaintiff has appealed the Court's order to the U.S. Court of Appeals for the First Circuit in the matter captioned Olsen v. Agenus, Inc., et al., No. 26-01421. In his appeal, the lead plaintiff contended that the Court erred as a matter of law in dismissing the claims against the Company and Garo Armen. The Company argued that the complaint failed to adequately plead the required elements of the claims and that the dismissal order should be affirmed. Briefing on the appeal concluded in September 2026. Oral argument on the appeal has not yet been scheduled, and a decision remains pending.

The Company has also been served with four derivative actions filed in the Court between November 2024 and January 2025 by purported stockholders. These actions name certain of the Company's executives and directors and allege that defendants made false or misleading statements and omissions of material fact related to the efficacy and commercial prospects of BOT and BAL. Plaintiffs seek an award of damages and an order directing the Company to reform and improve its corporate governance and internal procedures. On May 2, 2025, the Court consolidated the four actions in Case No. 1:24-cv-12823 and stayed all deadlines pending future developments in the securities class action. The Company is unable to estimate a range of loss, if any, that could result from an adverse outcome in these consolidated actions.

The Company is not currently a party to any other material legal proceedings. From time to time, the Company may be subject to various legal proceedings and claims that arise in the ordinary course of business. Regardless of outcome, litigation can have a material adverse effect on the Company because of defense and settlement costs, diversion of management resources, and other factors.