X0306 4 2021-09-10 0 0001674416 CRISPR Therapeutics AG CRSP 0001708172 KASINGER JAMES R. C/O CRISPR THERAPEUTICS, INC. 610 MAIN STREET CAMBRIDGE MA 02139 0 1 0 0 General Counsel and Secretary Common Shares 2021-09-10 4 M 0 10000 A 33911 D Common Shares 2021-09-13 4 F 0 4741 117.86 D 29170 D Restricted Stock Units 2021-09-10 4 D 0 10000 D Common Shares 10000 0 D The restricted stock unit award was granted on September 10, 2019 with respect to 10,000 Common Shares, with all shares vesting on September 10, 2021. Each restricted stock unit represents a contingent right to receive one share of CRSP Common Shares. Amount reported represents the number of shares required to be sold by the reporting person to cover the tax withholding obligation in connection with the vesting of these restricted stock units. This sale is mandated by the Company's RSU Settlement Policy to fund the tax withholding obligation and does not represent a discretionary trade by the reporting person. /s/ Michael Esposito, attorney-in-fact 2021-09-14