Barton Russell 4

Accession 0001628280-26-002958

CIK 0001576885other

Filed

Jan 20, 7:00 PM ET

Accepted

Jan 21, 6:30 PM ET

Size

7.3 KB

Accession

0001628280-26-002958

AI-generated summary of this filing

Updated Jan 21, 2026

Acumen (ABOS) COO Barton Russell Receives Award of 211,500 Shares

What Happened

Barton Russell, Chief Operating Officer of Acumen Pharmaceuticals (ABOS), was granted a total of 211,500 equity awards on 2026-01-16: 84,600 restricted stock units (RSUs) and 126,900 derivative awards (stock option-style units). Each line is reported as acquired at $0.00, so the filing shows $0 cash paid.

Key Details

Transaction date: 2026-01-16; Form 4 filed 2026-01-21 (filed within the SEC’s two-business-day reporting window for this trade date, accounting for the MLK Day holiday).
Price: $0.00 reported for both awards; total reported cash consideration = $0.
Shares owned after transaction: not specified in the supplied filing details.
Footnotes:
- F1: 84,600 RSUs — each RSU converts to one share at vesting; vests in three equal annual installments beginning one year after the grant, subject to continued service.
- F2: 126,900 derivative award — shares subject to the option vest in 48 equal monthly installments (fully vested on the fourth anniversary), subject to continued service.
Transaction code: "A" = grant/award (compensation issuance), not a market buy or sale.

Context

RSUs are compensatory awards that convert to shares only as they vest; the derivative award is an option-like grant that vests monthly and must be exercised per plan terms before becoming shares. These awards are typical executive compensation and do not reflect an open-market purchase or sale by the insider.

Form 4

Period: 2026-01-16

Chief Operating Officer

Transactions

Award
Common Stock
[F1]
2026-01-16+84,600→ 207,869 total
Award
Employee Stock Option (right to buy)
[F2]
2026-01-16+126,900→ 126,900 total
Exercise: $1.89Exp: 2036-01-16→ Common Stock (126,900 underlying)

Footnotes (2)

[F1]Represents 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 three equal annual installments commencing one year after the grant date, subject to the Reporting Person's continuous service through each such vesting date.
[F2]The shares subject to the option will vest in 48 equal monthly installments such that the option is fully vested on the fourth anniversary of the date of grant, subject to the Reporting Person's continuous service through each such vesting date.

Signature

/s/ Derek Meisner, Attorney-in-Fact|2026-01-21

1 file

Acumen Pharmaceuticals, Inc.

CIK 0001576885

Entity typeother