X0306 4 2021-03-31 0 0001745999 Beam Therapeutics Inc. BEAM 0001786484 Burrell Terry-Ann C/O BEAM THERAPEUTICS INC. 26 LANDSDOWNE STREET CAMBRIDGE MA 02139 0 1 0 0 CFO Common Stock 2021-03-31 4 A 0 17500 0.00 A 24809 D Stock Option (Right to Buy) 80.04 2021-03-31 4 A 0 35000 0.00 A 2031-03-31 Common Stock 35000 35000 D Represents restricted stock units ("RSUs") granted to the Reporting Person under the Company's 2019 Equity Incentive Plan. Each RSU represents the contingent right to receive one share of the Company's common stock. The RSUs vest in four substantially equal annual installments on each of the first four anniversaries of the date of grant, subject to the Reporting Person's continued service with the Company through each vesting date. The stock option vests in equal monthly installments each month following the date of grant for the subsequent 48 months, subject to the Reporting Person's continued service with the Company through each vesting date. By: Christine Bellon, Attorney-in-fact 2021-04-02