X0206 3 2021-07-22 0 0001619856 Caribou Biosciences, Inc. CRBU 0001871131 Kanner Steven C/O CARIBOU BIOSCIENCES, INC. 2929 7TH STREET, SUITE 105 BERKELEY CA 94710 0 1 0 0 See Remarks Common Stock 100171 D Stock Option (Right to Buy) 1.81 2027-07-11 Common Stock 171388 D Stock Option (Right to Buy) 1.81 2028-03-07 Common Stock 5577 D Stock Option (Right to Buy) 2.68 2029-09-30 Common Stock 146748 D Stock Option (Right to Buy) 4.11 2031-03-29 Common Stock 231914 D The option became fully exercisable on June 30, 2021. 1/4th of the shares subject to this option vested on October 1, 2020 and an additional 1/48th of the aggregate number of shares subject to the option have vested or will vest on the corresponding day of each month thereafter, subject to the reporting person's continued services to the Issuer through the applicable vesting date. 1/4th of the shares subject to this option will vest on March 2, 2022 and an additional 1/48th of the aggregate number of shares subject to the option will vest on the corresponding day of each month thereafter, subject to the reporting person's continued service to the Issuer through the applicable vesting date. Chief Scientific Officer Exhibit 24 - Power of Attorney. /s/ Steven B. Kanner 2021-07-22