Acumen Pharmaceuticals Inc

From time to time, our officers (as defined in Rule 16a-1(f)) and directors may enter into Rule 10b5-1 ornon-Rule 10b5-1 trading plans (as each such term is defined in Item 408 of Regulation S-K). The trading plans are intended to satisfy the affirmative defense in Rule 10b5-1(c). During the three months ended June 30, 2024, our officers and directors took the following actions with respect to 10b5-1 trading plans:

On June 24, 2024, Daniel O’Connell, our Chief Executive Officer, entered into a Rule 10b5-1 trading plan that provides that Mr. O’Connell, acting through a broker, may sell (1) up to an aggregate of 477,000 shares of our common stock received upon the settlement of restricted stock unit (“RSU”) awards granted to Mr. O’Connell as equity incentive compensation, which sales may occur from January 3, 2025 to December 31, 2027; and (2)433,567 shares of our common stock received upon the exercise of option awards granted to Mr. O’Connell as equity incentive compensation, which sales may occur from October 24, 2024 to June 30, 2025.

On May 15, 2024, Derek Meisner, our Chief Legal Officer, entered into a Rule 10b5-1 trading plan that provides that Mr. Meisner, acting through a broker, may sell (1) up to 108,867 shares of our common stock received upon the settlement of RSU awards granted to Mr. Meisner as equity incentive compensation, which sales may occur from January 3, 2025 to July 31, 2028; and (2)482,800 shares of our common stock received upon the exercise of option awards granted to Mr. Meisner as equity incentive compensation, which sales may occur from September 17, 2024 to July 31, 2028.