X0609 4 2026-10-15 0001745999 Beam Therapeutics Inc. BEAM 0001786304 Evans John M. false C/O BEAM THERAPEUTICS INC., 238 MAIN STREET CAMBRIDGE MA 02142 true true false false CEO true Common Stock 2026-10-15 4 M false 25000 1.03 A 1072205 D Common Stock 2026-10-15 4 S false 25000 23.5660 D 1047205 D Common Stock 2026-10-16 4 M false 25000 1.03 A 1072205 D Common Stock 2026-10-16 4 S false 25000 23.9838 D 1047205 D Common Stock 103000 I By John M. Evans, III 2018 Irrevocable Trust Stock Option (Right to Buy) 1.03 2026-10-15 4 M false 25000 0 D 2028-07-13 Common Stock 25000 180804 D Stock Option (Right to Buy) 1.03 2026-10-16 4 M false 25000 0 D 2028-07-13 Common Stock 25000 155804 D The stock options were exercised and the shares of common stock were sold pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on June 16, 2026. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $23.23 to $23.84, inclusive. The Reporting Person undertakes to provide to Beam Therapeutics Inc. ("BEAM"), any security holder of BEAM or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $23.66 to $24.56, inclusive. The Reporting Person undertakes to provide to BEAM, any security holder of BEAM or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. On July 13, 2018, the Reporting Person was granted an option to purchase 539,645 shares of common stock, which vested as to 25% of the underlying shares on January 8, 2019 and in 36 equal monthly installments thereafter. By: /s/ Christine Bellon, Attorney-in-fact 2026-10-16