Form 4 Filing for Alnylam Pharmaceuticals, Inc. - Colleen F. Reitan

This filing details transactions by Colleen F. Reitan, a director at Alnylam Pharmaceuticals, Inc. (ALNY). On May 20, 2026, Reitan acquired 671 shares of Common Stock under a restricted stock unit (RSU) grant from the 2018 Stock Incentive Plan. These RSUs vest on the first anniversary of the grant date or earlier upon retirement/resignation. Additionally, Reitan was granted a stock option to purchase 1441 shares of Common Stock, also vesting on the first anniversary of the grant date or earlier upon retirement/resignation. The option has an exercise price of $298.48 and an expiration date of May 20, 2036. These transactions are marked as indirect ownership.