ALNYLAM PHARMACEUTICALS INC

Adoption of 10b5-1 Trading Plans by Our Officers and Directors

During our fiscal quarter ended June 30, 2024, certain of our officers (as defined in Rule 16a-1(f) under the Exchange Act) and directors entered into contracts, instructions or written plans for the purchase or sale of our securities that are intended to satisfy the conditions specified in Rule 10b5-1(c) under the Exchange Act for an affirmative defense against liability for trading in securities on the basis of material nonpublic information. We refer to these contracts, instructions, and written plans as “Rule 10b5-1 trading plans” and each one as a “Rule 10b5-1 trading plan.” We describe the material terms of these Rule 10b5-1 trading plans below.

Kevin Fitzgerald, Ph.D., Executive Vice President, Chief Scientific Officer

On May 10, 2024, Kevin Fitzgerald, Ph.D., our Executive Vice President, Chief Scientific Officer, entered into a Rule 10b5-1 trading plan that provides that Dr. Fitzgerald, acting through a broker, may sell up to an aggregate of 50,634 shares of our common stock received upon the settlement of awards granted to Dr. Fitzgerald as equity incentive compensation, subject to adjustments for stock splits, stock combinations, stock dividends and other similar changes to our common stock. Sales of shares under the plan may only occur from August 11, 2024 to May 10, 2025. The plan is scheduled to terminate on May 10, 2025, subject to earlier termination upon the sale of all shares subject to the plan, upon termination by Dr. Fitzgerald or the broker, or as otherwise provided in the plan.

Dennis A. Ausiello, M.D., Director

On May 3, 2024, Dennis A. Ausiello, M.D., a member of our board of directors, entered into a Rule 10b5-1 trading plan that provides that Dr. Ausiello, acting through a broker, may sell up to an aggregate of 20,250 shares of our common stock received upon the exercise of options granted to Dr. Ausiello as director compensation, subject to adjustments for stock splits, stock combinations, stock dividends and other similar changes to our common stock. Sales of shares under the plan may only occur if the market price of our common stock is above specified prices from August 5, 2024 to May 20, 2025. The plan is scheduled to terminate on May 20, 2025, subject to earlier termination upon the sale of all shares subject to the plan upon termination by Dr. Ausiello or the broker, or as otherwise provided in the plan.

Stockholder Proposals for 2025 Annual Meeting

Our notice of 2024 annual meeting of stockholders and proxy statement on Schedule 14A, which was filed with the Securities and Exchange Commission on April 1, 2024, contained a typographical error in the section entitled “Additional Information and Other Matters—Stockholder Proposals” solely related to the dates by which a stockholder must provide notice to the Company if the stockholder would like to (a) submit a stockholder proposal for possible inclusion in our proxy statement for the 2025 annual meeting of stockholders, or the 2025 Proxy Statement and (b) present business at our 2025 annual meeting of stockholders that the stockholder does not intend to include in the 2025 Proxy. The corrected section is set forth below:

STOCKHOLDER PROPOSALS

In order to be included in the proxy materials for the 2025 annual meeting of stockholders, stockholders’ proposals must be received by us at our principal executive offices, 675 West Kendall Street, Henri A. Termeer Square, Cambridge, Massachusetts 02142 no later than December 2, 2024. We suggest that proponents submit their proposals by certified mail, return receipt requested, addressed to our Corporate Secretary. In addition, our bylaws require that we be given advance notice of stockholder nominations for election to our board of directors and of other matters which stockholders wish to present for action at an annual meeting of stockholders, other than matters included in our proxy statement. The required notice must be in writing and received by our corporate secretary at our principal offices not later than February 15, 2025 (90 days prior to the first anniversary of our 2024 annual meeting of stockholders) and not before January 16, 2025 (120 days prior to the first anniversary of our 2024 annual meeting of stockholders). However, if the 2025 annual meeting of stockholders is advanced by more than 20 days, or delayed by more than 60 days, from the first anniversary of the 2024 annual meeting of stockholders, notice must be received not earlier than the 120th day prior to such annual meeting and not later than the close of business on the later of (1) the 90th day prior to such annual meeting and (2) the 10th day following the date on which notice of the date of such annual meeting was mailed or public disclosure of the date of such annual meeting was made, whichever occurs first.

Our bylaws also specify requirements relating to the content of the notice which stockholders must provide, including a stockholder nomination for election to our board of directors, to be properly presented at the 2025 annual meeting of stockholders. Proxies solicited by the board will confer discretionary voting authority with respect to these proposals, subject to SEC rules governing the exercise of this authority.

To comply with the universal proxy rules, stockholders who intend to solicit proxies in support of director nominees other than the company’s nominees must provide notice that sets forth the information required by Rule 14a-19 under the Exchange Act no later than March 17, 2025.