Key facts
- This page summarizes RA CAPITAL MANAGEMENT, L.P.'s Form 4 filing for Acumen Pharmaceuticals, Inc. (ABOS).
- 2 reported transactions and 5 derivative rows are listed below.
- Accepted by SEC: 05 Jun 2026, 17:12.
RA CAPITAL MANAGEMENT, L.P. - 03 Jun 2026 Form 4 Insider Report for Acumen Pharmaceuticals, Inc. (ABOS)
- Reporting relationship
- Director, 10%+ Owner
- Issuer ticker
- ABOS
- Reported as of
- 03 Jun 2026
- Net transaction value
- $0
- SEC form
- 4
- Accepted by SEC
- 05 Jun 2026, 17:12:37 UTC
- Prior SEC filing
- 01 Jun 2026
- Next SEC filing
- 08 Jun 2026
- Source filing
- View source filing
- Reporting owner signature
- /s/ Peter Kolchinsky, Manager of RA Capital Management, L.P.
Source evidence
Original filing metadata and source links for verification.
5 source fields
Reporting owner
1 detail
Key filing fact
RA CAPITAL MANAGEMENT, L.P. filed Form 4 for Acumen Pharmaceuticals, Inc. (ABOS) on 05 Jun 2026.
Change
- Previous filing in this sequence was filed on 01 Jun 2026.
- Current net transaction value: $0.
Research use
- This tells you what this filing adds before you inspect full transaction and derivative tables.
- You can trace every row back to the original SEC filing document.
Evidence
Filed on Form 4
View source filing
Ownership activity is grounded in SEC Form 4 disclosures.
Reporting Owners (5)
CIK 0001346824
Primary reporting owner
RA CAPITAL MANAGEMENT, L.P.
- Relationship
- Director, 10%+ Owner
- Address
- 200 BERKELEY STREET, 18TH FLOOR, BOSTON
- Signature
- /s/ Peter Kolchinsky, Manager of RA Capital Management, L.P.
- Signature date
- 05 Jun 2026
CIK 0001315082
RA Capital Healthcare Fund LP
- Relationship
- Director, 10%+ Owner
- Address
- 200 BERKELEY STREET, 18TH FLOOR, BOSTON
- Signature
- /s/ Peter Kolchinsky, Manager of RA Capital Healthcare Fund GP, LLC, the General Partner of RA Capital Healthcare Fund, L.P.
- Signature date
- 05 Jun 2026
CIK 0001825376
RA Capital Nexus Fund II, L.P.
- Relationship
- Director
- Address
- 200 BERKELEY STREET, 18TH FLOOR, BOSTON
- Signature
- /s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund II GP, LLC, the General Partner of RA Capital Nexus Fund II, L.P.
- Signature date
- 05 Jun 2026
CIK 0001384859
Kolchinsky Peter
- Relationship
- Director, 10%+ Owner
- Address
- C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON
- Signature
- /s/ Peter Kolchinsky, individually
- Signature date
- 05 Jun 2026
CIK 0001619841
Shah Rajeev M.
- Relationship
- Director, 10%+ Owner
- Address
- C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON
- Signature
- /s/ Rajeev Shah, individually
- Signature date
- 05 Jun 2026
Reported non-derivative transactions
Shares, units, or other non-derivative securities reported in this filing.
ABOS
transaction
Common Stock
Award
- Transaction value
- Shares
- +35,500
- Change %
- +277%
- Price
- $0.000000*
- Shares after
- 48,300
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F1, F2, F3
ABOS
transaction
Common Stock
Award
- Transaction value
- Shares
- +35,500
- Change %
- +277%
- Price
- $0.000000*
- Shares after
- 48,300
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F1, F2, F3
ABOS
transaction
Common Stock
Award
- Transaction value
- Shares
- +35,500
- Change %
- +277%
- Price
- $0.000000*
- Shares after
- 48,300
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F1, F2, F3
ABOS
transaction
Common Stock
Award
- Transaction value
- Shares
- +35,500
- Change %
- +277%
- Price
- $0.000000*
- Shares after
- 48,300
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F1, F2, F3
ABOS
transaction
Common Stock
Award
- Transaction value
- Shares
- +35,500
- Change %
- +277%
- Price
- $0.000000*
- Shares after
- 48,300
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F1, F2, F3
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 19,103,785
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F4
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 19,103,785
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F4
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 19,103,785
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F4
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 19,103,785
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F4
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 19,103,785
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F4
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 1,300,034
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F5
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 1,300,034
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F5
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 1,300,034
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F5
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 1,300,034
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F5
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 1,300,034
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F5
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 588,850
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F6
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 588,850
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F6
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 588,850
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F6
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 588,850
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F6
ABOS
holding
Common Stock
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 588,850
- Date
- 03 Jun 2026
- Ownership
- See footnotes
- Footnotes
- F2, F6
Reported derivative securities
Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.
ABOS
transaction
Derivative
Stock Option (Right to Buy)
Award
- Transaction value
- Shares
- +53,250
- Change %
- Price
- $0.000000*
- Shares after
- 53,250
- Date
- 03 Jun 2026
- Ownership
- See Footnotes
- Underlying class
- Common Stock
- Underlying amount
- 53,250
- Exercise price
- $2.29
- Footnotes
- F2, F3, F7
ABOS
transaction
Derivative
Stock Option (Right to Buy)
Award
- Transaction value
- Shares
- +53,250
- Change %
- Price
- $0.000000*
- Shares after
- 53,250
- Date
- 03 Jun 2026
- Ownership
- See Footnotes
- Underlying class
- Common Stock
- Underlying amount
- 53,250
- Exercise price
- $2.29
- Footnotes
- F2, F3, F7
ABOS
transaction
Derivative
Stock Option (Right to Buy)
Award
- Transaction value
- Shares
- +53,250
- Change %
- Price
- $0.000000*
- Shares after
- 53,250
- Date
- 03 Jun 2026
- Ownership
- See Footnotes
- Underlying class
- Common Stock
- Underlying amount
- 53,250
- Exercise price
- $2.29
- Footnotes
- F2, F3, F7
ABOS
transaction
Derivative
Stock Option (Right to Buy)
Award
- Transaction value
- Shares
- +53,250
- Change %
- Price
- $0.000000*
- Shares after
- 53,250
- Date
- 03 Jun 2026
- Ownership
- See Footnotes
- Underlying class
- Common Stock
- Underlying amount
- 53,250
- Exercise price
- $2.29
- Footnotes
- F2, F3, F7
ABOS
transaction
Derivative
Stock Option (Right to Buy)
Award
- Transaction value
- Shares
- +53,250
- Change %
- Price
- $0.000000*
- Shares after
- 53,250
- Date
- 03 Jun 2026
- Ownership
- See Footnotes
- Underlying class
- Common Stock
- Underlying amount
- 53,250
- Exercise price
- $2.29
- Footnotes
- F2, F3, F7
* marks a reported price that did not pass the local price check.
Additional SEC filing notes
Filing notes and footnotes
Explanation of responses 7 footnotes
Footnote F1
Represents a restricted stock unit ("RSU") award to Laura Stoppel. 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 Dr. Stoppel's continuous service through such vesting date.
Footnote F2
RA Capital Management, L.P. (the "Adviser") is the investment manager for 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 general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, the Nexus Fund II, Dr. Kolchinsky, and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein.
Footnote F3
Under Dr. Stoppel's arrangement with the Adviser, Dr. Stoppel holds the RSUs and the option for the benefit of the Fund, the Nexus Fund II and the Account. Dr. Stoppel 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 Persons therefore disclaim beneficial ownership of the RSUs, the option and the underlying common stock.
Footnote F4
Held directly by the Fund.
Footnote F5
Held directly by the Nexus Fund II.
Footnote F6
Held directly by the Account.
Footnote F7
Represents the award of an option to Dr. Stoppel. The 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 Dr. Stoppel's continuous service through such vesting date.
SEC remarks
Laura Stoppel, a Principal of the Adviser, serves on the Issuer's board of directors.