X0306 4 2021-01-12 0 0001650664 Editas Medicine, Inc. EDIT 0001755098 ROBERTSON MICHELLE C/O EDITAS MEDICINE, INC. 11 HURLEY ST. CAMBRIDGE MA 02141 0 1 0 0 Chief Financial Officer Common Stock 2021-01-12 4 S 0 1568 78.27 D 18432 D Sale was effected pursuant to a durable automatic sales instruction plan adopted by the Reporting Person on December 30, 2019, and represents the sale of shares by the Issuer necessary to meet tax withholding obligations as a result of vesting in restricted stock units on January 9, 2021. The sale does not represent a discretionary trade by the Reporting Person. /s/ Michelle Robertson 2021-01-13