Igm Biosciences, Inc. SEC Filings

IGM Biosciences director Elizabeth H.Z. Thompson reported a disposition of 7,196 shares of the company’s common stock on 08/14/2025 in connection with the completion of a merger. Under the Merger, each outstanding share of IGM common stock was cancelled and converted into the right to receive $1.247 in cash plus one contractual contingent value right (CVR) governed by a Contingent Value Rights Agreement. Following the reported transaction the reporting person beneficially owned 0 shares of common stock.

The filing is a Form 4 disclosure of insider changes tied directly to the Merger transaction and shows the insider’s equity position was eliminated as part of the deal consideration.

IGM Biosciences insider Form 4: Director William Strohl reported a disposition of 125,000 shares of IGM Biosciences common stock on 08/14/2025, leaving him with 0 shares following the transaction. The filing explains this disposal resulted from a merger in which Concentra Merger Sub V, Inc. merged into IGM Biosciences and the company became a wholly owned subsidiary of Concentra Biosciences, LLC. Each outstanding share of common stock was cancelled and converted into the right to receive $1.247 in cash and one contingent value right (CVR) under a Contingent Value Rights Agreement.

IGM Biosciences insider report: Mary Beth Harler, who serves as both Chief Executive Officer and a director, reported the disposition of 323,680 shares of IGM Biosciences common stock on 08/14/2025. Following the reported transaction, Harler beneficially owned 0 shares. The filing explains these shares (including previously reported restricted stock units) were cancelled and converted as part of a merger transaction: each outstanding share and RSU was converted into $1.247 in cash plus one contractual contingent value right under a Contingent Value Rights Agreement. The Form 4 indicates the change in beneficial ownership resulted from the merger consummated on that date.

IGM Biosciences completed a merger on August 14, 2025 that converted all outstanding common stock into cash and contingent value rights. Under the Agreement and Plan of Merger, Merger Sub merged into IGM with IGM surviving as a wholly owned subsidiary of Concentra Biosciences, LLC (Parent). Each share of IGM common stock was cancelled and converted into $1.247 in cash plus one contractual contingent value right (CVR) governed by a Contingent Value Rights Agreement. Reporting person M. Kathleen Behrens, a director, reported dispositions of all her previously held shares, including shares held directly and indirectly through trusts, resulting in zero common shares beneficially owned following these transactions.

IGM Biosciences completed a merger and terminated its S-8 offerings, removing unsold registered securities. Under an Agreement and Plan of Merger dated July 1, 2025, IGM merged into a Concentra Biosciences subsidiary and became a wholly owned subsidiary of Concentra when the merger closed on August 14, 2025. Each outstanding share of IGM common stock (other than treasury shares, shares held by Parent/Merger Sub, and shares of stockholders who properly exercised appraisal rights) was converted into $1.247 in cash per share and one non-transferable contractual contingent value right (CVR) per share. As a result of the Merger, the registrant terminated all offerings under the listed Form S-8 registration statements and filed post-effective amendments to withdraw and remove any unissued and unsold securities that remained registered.

IGM Biosciences completed a merger into a subsidiary of Concentra Biosciences and, as a result, has terminated and withdrawn unissued securities from multiple Form S-8 registration statements. The Registrant entered into a merger agreement on July 1, 2025, and on August 14, 2025 Merger Sub was merged into the company with the company surviving as a wholly owned subsidiary of Parent.

Under the Merger each outstanding share (other than treasury shares, shares owned by Parent/Merger Sub, and shares of stockholders who validly exercised appraisal rights) was converted into the right to receive $1.247 in cash per share plus one non-transferable contractual contingent value right per share. The company removed all unsold securities registered under the referenced S-8 registration statements and terminated their effectiveness.

The registrant, IGM Biosciences, Inc., has filed post-effective amendments to multiple Form S-8 registration statements to withdraw and remove any unissued and unsold securities that remained registered under those statements after the termination of the offerings. The withdrawals follow the closing of a merger in which Concentra Merger Sub V, Inc. merged into IGM with IGM surviving as a wholly owned subsidiary of Concentra Biosciences, LLC. Under the merger each outstanding share (with customary exceptions) was converted into $1.247 in cash per share plus one non-transferable contingent value right per share. As a result, the company terminated all offerings made under the listed registration statements and has removed the unsold registered shares from registration.

IGM Biosciences completed a merger into Concentra Biosciences and terminated its pending employee equity registrations. Under a Merger Agreement dated July 1, 2025, the company was merged into a Concentra subsidiary on August 14, 2025, and became a wholly owned subsidiary of Concentra. Each outstanding public share (with limited exceptions) was converted into $1.247 in cash per share plus one non-transferable contingent value right per share. As a result, the registrant has ended all offerings under multiple Form S-8 registration statements and filed post-effective amendments to withdraw any unissued and unsold securities that remained registered.

IGM Biosciences, Inc. filed post-effective amendments to multiple Form S-8 registration statements to withdraw and remove any unissued and unsold securities after the company completed a merger. The company entered into a Merger Agreement on July 1, 2025, and on August 14, 2025 the merger closed with Concentra Merger Sub V, Inc. merging into IGM and IGM surviving as a wholly owned subsidiary of Concentra Biosciences, LLC. As part of the merger, each outstanding share of IGM common stock (subject to limited exceptions) was converted into $1.247 in cash per share and one non-transferable contractual contingent value right (CVR) per share. Because the company is now a wholly owned subsidiary, it has terminated all offerings of its securities under the listed registration statements and removed from registration all unsold securities covered by those statements.