Alnylam Pharmaceuticals CHRO Melissa McLaughlin Sells 3,810 Shares for Tax Withholding

This Form 4 filing reports that Melissa McLaughlin, Chief Human Resources Officer of Alnylam Pharmaceuticals, sold 3,810 shares of company common stock across multiple transactions on April 2 and April 6, 2026. The sales were executed at prices ranging from $316.04 to $334.31 per share, generating total proceeds of approximately $1.2 million. The majority of the sales (2,624 shares) on April 2 were mandatory sell-to-cover transactions to satisfy tax withholding obligations related to the vesting and settlement of restricted stock units. The remaining 1,286 shares sold on April 6 were executed pursuant to a Rule 10b5-1(c) trading plan adopted on December 16, 2025. Following these transactions, McLaughlin's direct ownership decreased to 9,443 shares. The filing indicates these were routine transactions for tax purposes and planned sales under a pre-established trading plan.