X0508 4 2026-02-02 0001733294 Generation Bio Co. GBIO 0001828153 Howze Yalonda C/O GENERATION BIO CO. 301 BINNEY STREET, SUITE 401 CAMBRIDGE MA 02142 false true false false INTERIM CEO & PRESIDENT 0 Common Stock 2026-02-02 4 M 0 1673 A 4254 D Common Stock 2026-02-02 4 F 0 495 5.64 D 3759 D Restricted Stock Units 2026-02-02 4 M 0 1673 0 D Common Stock 1673 0 D Each restricted stock unit represents the right to receive one share of the company's common stock. The grant of 53,550 restricted stock units was made on April 5, 2023. Pursuant to the terms of that certain Agreement and Plan of Merger, by and among the Issuer, XOMA Royalty Corporation ("Parent") and Parent's wholly-owned subsidiary, XRA 7 Corp., dated as of December 15, 2025 (the "Merger Agreement"), prior to the effective time of the merger as contemplated by the Merger Agreement, each restricted stock unit of the Issuer that was outstanding and unvested became vested in full on February 2, 2026. /s/ Shawna-Gay White, Attorney-in-Fact 2026-02-04