Acumen (NASDAQ: ABOS) legal chief gets 99,133 RSUs and 148,700 options

Rhea-AI Filing Summary

Acumen Pharmaceuticals’ Chief Legal Officer Derek M. Meisner reported new equity awards in the company. On January 16, 2026, he received 99,133 shares of Common Stock as a restricted stock unit (RSU) award at a price of $0 per share, bringing his directly owned Common Stock to 182,933 shares. Each RSU represents a right to receive one share of Common Stock and will vest in three equal annual installments starting one year after the grant date, as long as he continues in service.

He also received an employee stock option to buy 148,700 shares of Common Stock at an exercise price of $1.89 per share, with no cost reported for the grant itself. These options vest in 48 equal monthly installments and are fully vested on the fourth anniversary of the grant date, subject to his continuous service, and expire on January 16, 2036.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Meisner Derek M

Role Chief Legal Officer & Corp Sec

Type	Security	Shares	Price	Value
Grant/Award	Employee Stock Option (right to buy)	148,700	$0.00	--
Grant/Award	Common Stock	99,133	$0.00	--

Holdings After Transaction: Employee Stock Option (right to buy) — 148,700 shares (Direct); Common Stock — 182,933 shares (Direct)

Footnotes (1)

1. 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. 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.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Meisner Derek M

(Last) (First) (Middle)

C/O ACUMEN PHARMACEUTICALS, INC.

1210-1220 WASHINGTON STREET, SUITE 210

(Street)

NEWTON MA 02465

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Acumen Pharmaceuticals, Inc. [ ABOS ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Legal Officer & Corp Sec

3. Date of Earliest Transaction (Month/Day/Year)
01/16/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	01/16/2026		A		99,133(1)	A	$0	182,933	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option (right to buy)	$1.89	01/16/2026		A		148,700		(2)	01/16/2036	Common Stock	148,700	$0	148,700	D

Explanation of Responses:

1. 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.

2. 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.

Remarks:

	/s/ Derek Meisner	01/21/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did Acumen Pharmaceuticals (ABOS) report for Derek Meisner?

Derek M. Meisner, Chief Legal Officer & Corporate Secretary, reported grants of 99,133 RSUs of Common Stock and an employee stock option for 148,700 shares on January 16, 2026.

How many Acumen Pharmaceuticals (ABOS) shares does Derek Meisner own after this Form 4?

After the reported RSU grant, Derek Meisner beneficially owns 182,933 shares of Acumen Pharmaceuticals Common Stock directly, as shown in the filing.

What are the vesting terms of Derek Meisner’s RSUs at Acumen Pharmaceuticals (ABOS)?

The 99,133 RSUs vest in three equal annual installments starting one year after the January 16, 2026 grant date, subject to his continuous service at each vesting date.

What are the key details of Derek Meisner’s stock option grant at Acumen Pharmaceuticals (ABOS)?

He received an employee stock option for 148,700 shares of Common Stock with a $1.89 exercise price, vesting in 48 equal monthly installments and expiring on January 16, 2036.

Did Derek Meisner pay anything for the RSU and option grants at Acumen Pharmaceuticals (ABOS)?

The Form 4 reports the transaction price per share as $0.00 for both the 99,133-share RSU award and the 148,700-share stock option grant, reflecting no cash cost for receiving the awards.

Are Derek Meisner’s Acumen Pharmaceuticals (ABOS) equity holdings direct or indirect?

The filing indicates that both the Common Stock and the stock options reported are held directly (coded "D") by Derek Meisner, with no separate indirect ownership entity disclosed.