Equity	3 Months Ended
Mar. 31, 2026
Equity [Abstract]
Equity	Note N – Equity On March 14, 2024, we filed a Post-Effective Amendment to an Automatic Shelf Registration Statement on Form POSASR (file no. 333-272911) and a Post-Effective Amendments for Registration Statement on Form POS AM (file no. 333-272911) (together, the “Registration Statement”). The Registration Statement included both a base prospectus that covered the potential offering, issuance and sale from time to time of up to $300.0 million of common stock, preferred stock, warrants, debt securities and units of Agenus and a prospectus supplement for the potential offer and sale of up to 6,725,642 shares of common stock (the “Initial ATM Shares”) in “at the market” offerings pursuant to an At Market Issuance Sales Agreement by and between Agenus and B. Riley Securities, Inc. (the “Sales Agent”), dated as of July 22, 2020 (the “Sales Agreement”). On August 8, 2024, we filed an additional prospectus supplement for the potential offer and sale of up to an additional 13,834,015 shares of common stock (together with the Initial ATM Shares, the “Placement Shares”) in “at the market” offerings pursuant to the Sales Agreement. Sales pursuant to the Sales Agreement will be made only upon our instruction to the Sales Agent, and we cannot provide assurances that we will issue any additional Placement Shares pursuant to the Sales Agreement. During the three months ended March 31, 2026, we received net proceeds of approximately $1.0 million from the sale of approximately 284,000 shares of our common stock in at-the-market offerings under the Sales Agreement. In January 2026, we entered into an amendment and release agreement (the “Amendment Agreement”) with Ligand related to the Ligand Purchase Agreement and Ligand Warrant. The Amendment Agreement provided for a release by Ligand of liens it had on certain of the Company’s assets in exchange for a modification of the exercise price under the Ligand Warrant from $17.30 per share to $7.50 per share. In connection with the Zydus Asset Purchase Agreement and Securities Purchase Agreement described in Note R, on January 15, 2026, we issued to Zynext Ventures USA LLC 2,133,333 shares of our common stock and allocated $7.2 million of consideration from the Zydus Agreements to this sale, based on the fair value of our common stock on the closing date. On January 10, 2025, we entered into a payment agreement with Medpace, Inc. ("Medpace"), pursuant to which we agreed with Medpace to certain matters related to payments due to Medpace by us under a master services agreement with Medpace dated June 8, 2022. In connection with the agreements set forth in the payment agreement, we issued to Medpace in a private issuance 1,318,084 shares of our common stock (the "Medpace Shares"). The Medpace Shares were issued to and were held by Medpace as a deposit and to provide security for our payment obligations to Medpace under the payment agreement. In connection with a modification of the payment terms as provided for in the payment agreement, on December 29, 2025, we entered into a forbearance agreement with Medpace pursuant to which we agreed, among other things, to register for resale the Medpace Shares. In addition, Medpace agreed to, under certain circumstances if applicable (including the payment in cash by us of amounts due under the payment agreement), return some or all of the Medpace Shares to us. As of and for the year ended December 31, 2025, these shares were deemed to be contingently returnable and as such, the Medpace Shares were not deemed outstanding at as of December 31, 2025. In connection with the closing of the Zydus Asset Purchase Agreement in January 2026, we fully settled our obligation to Medpace in cash. As such, Medpace returned all of the 1,318,084 shares to us.

Equity

3 Months Ended

Mar. 31, 2026

Note N – Equity

On March 14, 2024, we filed a Post-Effective Amendment to an Automatic Shelf Registration Statement on Form POSASR (file no. 333-272911) and a Post-Effective Amendments for Registration Statement on Form POS AM (file no. 333-272911) (together, the “Registration Statement”). The Registration Statement included both a base prospectus that covered the potential offering, issuance and sale from time to time of up to $300.0 million of common stock, preferred stock, warrants, debt securities and units of Agenus and a prospectus supplement for the potential offer and sale of up to 6,725,642 shares of common stock (the “Initial ATM Shares”) in “at the market” offerings pursuant to an At Market Issuance Sales Agreement by and between Agenus and B. Riley Securities, Inc. (the “Sales Agent”), dated as of July 22, 2020 (the “Sales Agreement”). On August 8, 2024, we filed an additional prospectus supplement for the potential offer and sale of up to an additional 13,834,015 shares of common stock (together with the Initial ATM Shares, the “Placement Shares”) in “at the market” offerings pursuant to the Sales Agreement. Sales pursuant to the Sales Agreement will be made only upon our instruction to the Sales Agent, and we cannot provide assurances that we will issue any additional Placement Shares pursuant to the Sales Agreement.

During the three months ended March 31, 2026, we received net proceeds of approximately $1.0 million from the sale of approximately 284,000 shares of our common stock in at-the-market offerings under the Sales Agreement.

In January 2026, we entered into an amendment and release agreement (the “Amendment Agreement”) with Ligand related to the Ligand Purchase Agreement and Ligand Warrant. The Amendment Agreement provided for a release by Ligand of liens it had on certain of the Company’s assets in exchange for a modification of the exercise price under the Ligand Warrant from $17.30 per share to $7.50 per share.

In connection with the Zydus Asset Purchase Agreement and Securities Purchase Agreement described in Note R, on January 15, 2026, we issued to Zynext Ventures USA LLC 2,133,333 shares of our common stock and allocated $7.2 million of consideration from the Zydus Agreements to this sale, based on the fair value of our common stock on the closing date.

On January 10, 2025, we entered into a payment agreement with Medpace, Inc. ("Medpace"), pursuant to which we agreed with Medpace to certain matters related to payments due to Medpace by us under a master services agreement with Medpace dated June 8, 2022. In connection with the agreements set forth in the payment agreement, we issued to Medpace in a private issuance 1,318,084 shares of our common stock (the "Medpace Shares"). The Medpace Shares were issued to and were held by Medpace as a deposit and to provide security for our payment obligations to Medpace under the payment agreement.

In connection with a modification of the payment terms as provided for in the payment agreement, on December 29, 2025, we entered into a forbearance agreement with Medpace pursuant to which we agreed, among other things, to register for resale the Medpace Shares. In addition, Medpace agreed to, under certain circumstances if applicable (including the payment in cash by us of

amounts due under the payment agreement), return some or all of the Medpace Shares to us. As of and for the year ended December 31, 2025, these shares were deemed to be contingently returnable and as such, the Medpace Shares were not deemed outstanding at as of December 31, 2025. In connection with the closing of the Zydus Asset Purchase Agreement in January 2026, we fully settled our obligation to Medpace in cash. As such, Medpace returned all of the 1,318,084 shares to us.

- Definition

The entire disclosure for equity.

+ References

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+ Details

AGENUS INC 10-Q