SEC Form 4 · accession 0001628280-26-041263

Acumen Pharmaceuticals, Inc. · ABOS

Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗

Reporting owner

Director

Period of report

Jun 3, 2026

Accepted (ET)

Jun 5, 2026 · 4:27 pm EDT

Rule 10b5-1 plan

box not checked

Issuer CIK

0001576885

Table I — non-derivative securities

Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F2	Jun 3, 2026	A	35,500	$0.00	A	48,300	D

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Stock Option (right to buy)^F2,F3	$2.29	Jun 3, 2026	A	53,250	A	—	Jun 3, 2036	Common Stock	53,250	53,250	D

F1Represents a restricted stock unit ("RSU") award. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock. The RSUs will vest in full on the earlier of the first anniversary of the date of grant or the 2027 annual stockholder meeting, subject to the Reporting Person's continuous service through such vesting date.
F2Under the Reporting Person's arrangement with RA Capital Management, L.P. (the "Adviser"), the Reporting Person holds the option and RSUs for the benefit of the RA Capital Healthcare Fund, L.P. (the "Fund"), RA Capital Nexus Fund II, L.P. (the "Nexus Fund II") and a separately managed account (the "Account"). The Reporting Person is obligated to turn over to the Adviser any net cash or stock received upon exercise of the option or settlement of the RSUs, as applicable, which will offset advisory fees owed by the Fund, the Nexus Fund II and the Account to the Adviser. The Reporting Person therefore disclaims beneficial ownership of the option and RSUs and underlying common stock.
F3The shares subject to the option will vest in full on the earlier of the first anniversary of the date of grant or the 2027 annual stockholder meeting, subject to the Reporting Person's continuous service through such vesting date.