Transaction Details

Footnotes

These shares of common stock were sold pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 16, 2025. | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $22.03 to $22.70, 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 $22.34 to $23.21, 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. | Represents restricted stock units ("RSUs") granted to the Reporting Person under the BEAM 2019 Equity Incentive Plan. Each RSU represents the contingent right to receive one share of BEAM's common stock. The RSUs vest in four substantially equal installments on each of the first four anniversaries of the date of grant, subject to the Reporting Person's continued service with BEAM through each vesting date. | On May 8, 2018, the Reporting Person was granted an option to purchase shares of common stock, which vested as to 99,396 shares upon the achievement of a certain development milestone related to base editing applications. On April 3, 2024, the board of directors of BEAM determined that this performance condition was achieved, resulting in the vesting of 99,336 shares.