X0306 4 2021-07-29 0 0001850838 Omega Therapeutics, Inc. OMGA 0001192128 BESHAR LUKE M C/O OMEGA THERAPEUTICS, INC. 20 ACORN PARK DRIVE CAMBRIDGE MA 02140 1 0 0 0 Stock Option (Right to Buy) 17.00 2021-07-29 4 A 0 52941 0.00 A 2031-07-28 Common Stock 52941 52941 D The options vest and become exercisable with respect to 25% of the underlying shares on June 2, 2022 and in 36 equal monthly installments thereafter such that the option will become fully vested and exercisable on June 22, 2025, subject to the Reporting Person's continued service to the Issuer through each vesting date. /s/ Barbara Chan as Attorney-in-fact for Luke M. Beshar 2021-07-30