X0508 4 2026-02-04 0001681087 Tectonic Therapeutic, Inc. TECX 0002023849 Ruddy Marcella K. C/O TECTONIC THERAPEUTIC, INC. 490 ARSENAL WAY, SUITE 200 WATERTOWN MA 02472 false true false false Chief Medical Officer 0 Common Stock 2026-02-04 4 F 0 2064 23.22 D 53247 D This transaction reported represents the withholding of shares by the Issuer to satisfy the Reporting Person's tax withholding obligations in connection with the vesting and settlement of the restricted stock units granted on February 4, 2025. /s/ Daniel Lochner, Attorney-in-Fact 2026-02-10