Welcome to our dedicated page for Acumen Pharmaceuticals SEC filings (Ticker: ABOS), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Acumen Pharmaceuticals, Inc. filings document a clinical-stage biopharmaceutical issuer focused on Alzheimer’s disease programs targeting toxic soluble amyloid beta oligomers. Its Form 8-K reports include operating and financial results, business highlights, Regulation FD presentation updates, clinical and nonclinical program disclosures, and material agreements related to Enhanced Brain Delivery development.
Proxy materials describe annual meeting voting matters, board elections, auditor ratification, and equity incentive plan approvals. The filing record also discloses ABOS common stock registered on the Nasdaq Global Select Market, emerging growth company status, governance changes, capital-structure matters, and clinical and regulatory disclosure categories tied to drug development.
Acumen Pharmaceuticals reported a proposed sale of 2,090 common shares via a broker-assisted cashless exercise on 03/06/2026. The filing lists prior open-market sales by Derek Meisner across January–February 2026, including large blocks of 36,911 shares on 01/08/2026 and 15,085 shares on 01/26/2026.
Acumen Pharmaceuticals Chief Legal Officer Derek M. Meisner exercised employee stock options for 9,406 shares of common stock at a price of $1.85 per share and immediately sold 9,406 common shares in an open-market transaction at a weighted average price of $3.0099 per share. These sales occurred automatically under a Rule 10b5-1 trading plan adopted on March 29, 2025.
After these transactions, Meisner directly owned 173,999 shares of common stock and held 73,138 shares underlying employee stock options. The options vest in 48 equal monthly installments from the grant date, subject to continuous service.
Acumen Pharmaceuticals reported a Form 144 notice for the proposed sale of 9,406 shares of common stock on 02/27/2026. The filing identifies the sale method as a broker-assisted cashless exercise tied to employee stock options. The filing also lists multiple prior open-market dispositions by Derek Meisner during January 2026, with individual sales including 36,911 shares on 01/08/2026 and 15,085 shares on 01/26/2026.
Acumen Pharmaceuticals Chief Legal Officer Derek Meisner reported option exercises and related stock sales. On January 26 and 28, 2026, he exercised a total of 17,756 employee stock options at an exercise price of $1.85 per share, acquiring the same number of common shares.
On those same dates, he sold 17,756 common shares at weighted average prices of $3.0005 and $3.0016 per share under a pre-established Rule 10b5-1 trading plan. Following these transactions, he directly owned 173,999 common shares and retained vested and unvested stock options that vest in 48 equal monthly installments from the grant date.
Acumen Pharmaceuticals, Inc. insider plans to sell additional common stock under Rule 144. A notice covers the proposed sale of 2,671 shares of common stock through Merrill Lynch on 01/28/2026, with an aggregate market value of $8,017.29. The shares relate to an employee stock option exercise on the same date via a broker-assisted cashless transaction.
The filing also lists prior sales of Acumen Pharmaceuticals common stock by Derek Meisner over the past three months, including 4,000 shares for $7,838.00 on 01/05/2026 and 10,898 shares for $21,437.56 on 01/06/2026. Company shares outstanding are stated as 60,573,425, providing context for these transactions.
Acumen Pharmaceuticals insider plans additional stock sale under Rule 144. The notice covers up to 15,085 shares of common stock to be sold through Merrill Lynch on or about 01/27/2026 on the NASDAQ market, with an aggregate market value of $45,262.48. These shares were acquired the same day via a broker-assisted cashless exercise of employee stock options.
The filing also lists prior sales of Acumen Pharmaceuticals common stock during January 2026 by Derek Meisner, including multiple transactions ranging from 1,054 to 36,911 shares. Shares of Acumen Pharmaceuticals outstanding were 60,573,425 at the time referenced, providing context for the size of the planned and recent sales.
Acumen Pharmaceuticals Chief Legal Officer Derek M. Meisner reported three sales of common stock under pre-arranged Rule 10b5-1 trading plans. On January 21, 2026, he sold 2,247 shares at a weighted average price of $1.8083 per share through an automatic “sell to cover” transaction to satisfy tax withholding tied to vesting restricted stock units under a plan adopted on May 15, 2024. On January 22, 2026, he sold 1,054 shares at $1.84 per share, and on January 23, 2026, he sold 5,633 shares at a weighted average price of $1.9027 per share under a separate Rule 10b5-1 plan adopted on March 29, 2025. After these transactions, he directly owned 173,999 shares of Acumen Pharmaceuticals common stock.
Acumen Pharmaceuticals Chief Medical Officer Eric Siemers reported small automatic stock sales to cover taxes related to equity vesting. On January 21, 2026, he sold 2,331 shares of common stock at a weighted average price of $1.8035, and on January 22, 2026, he sold an additional 895 shares at $1.82 per share. The filing explains these were automatic “sell to cover” transactions to satisfy tax withholding obligations from vesting restricted stock units under a Rule 10b5-1 trading plan adopted on September 3, 2024. After these sales, Siemers beneficially owned 255,371 shares of Acumen common stock directly.
Acumen Pharmaceuticals insider activity: CFO & Chief Business Officer Matt Zuga reported small automatic stock sales tied to tax withholding. On 01/21/2026, he sold 2,473 shares of common stock at a weighted average price of $1.8072 per share, followed by a sale of 1,687 shares at $1.86 per share on 01/22/2026. These transactions were executed as “sell to cover” trades to satisfy tax obligations from vesting restricted stock units under a Rule 10b5-1 trading plan adopted on August 30, 2024. After these sales, he directly beneficially owns 304,924 shares of Acumen common stock.
Acumen Pharmaceuticals, Inc. Chief Executive Officer Daniel Joseph O'Connell reported automatic stock sales related to tax withholding. On January 21, 2026, he sold 9,346 shares of common stock at a weighted average price of $1.8112 per share. On January 22, 2026, he sold an additional 2,689 shares at a weighted average price of $1.8838 per share.
According to the footnotes, these transactions were automatic "sell to cover" trades to satisfy tax withholding obligations arising from the vesting of restricted stock units under a Rule 10b5-1 trading plan adopted on June 24, 2024. After these sales, O'Connell beneficially owned 881,275 shares of Acumen common stock directly.