Stock Option Grant and Restricted Stock Units for Peter N. Kellogg

This filing details a Form 4 filing by Peter N. Kellogg, a director at ALNYLAM PHARMACEUTICALS, INC. On May 20, 2026, Kellogg was granted stock options and restricted stock units (RSUs). The stock option, representing the right to buy, was granted with a vesting schedule tied to the first anniversary of the grant date or an earlier retirement/resignation. The exercise price for this option is $298.48 per share. Additionally, 671 shares of Common Stock were acquired through RSUs granted under the company's stock incentive plan. These RSUs also vest on the first anniversary of the grant date, subject to similar early retirement/resignation conditions. Following these transactions, Kellogg holds 1441 shares under the stock option and has a total of 1446 shares of Common Stock.