Acumen Pharmaceuticals (ABOS) CEO granted major RSU and option awards

Rhea-AI Filing Summary

Acumen Pharmaceuticals Chief Executive Officer and director Daniel Joseph O’Connell reported new equity awards in the form of restricted stock units and stock options. On January 20, 2026, he received 299,800 shares of Common Stock as a restricted stock unit (RSU) award at a price of $0, increasing his directly held Common Stock to 893,310 shares after the transaction. Each RSU represents the right to receive one share of Acumen’s Common Stock and will vest in three equal annual installments starting one year after the grant date, contingent on his continued service.

On the same date, O’Connell was also granted an employee stock option covering 450,000 shares of Common Stock at an exercise price of $1.86 per share. These options were awarded at no upfront cost and will vest in 48 equal monthly installments so that they are fully vested on the fourth anniversary of the grant date, again subject to his continuous service. Following this grant, he holds 450,000 stock options directly.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider OConnell Daniel Joseph

Role Chief Executive Officer

Type	Security	Shares	Price	Value
Grant/Award	Employee Stock Option (right to buy)	450,000	$0.00	--
Grant/Award	Common Stock	299,800	$0.00	--

Holdings After Transaction: Employee Stock Option (right to buy) — 450,000 shares (Direct); Common Stock — 893,310 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^*

OConnell Daniel Joseph

(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)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

3. Date of Earliest Transaction (Month/Day/Year)
01/20/2026

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	01/20/2026		A		299,800(1)	A	$0	893,310	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)	$1.86	01/20/2026		A		450,000		(2)	01/20/2036	Common Stock	450,000	$0	450,000	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, Attorney-in-Fact	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 transactions did Acumen Pharmaceuticals (ABOS) report for its CEO?

Acumen Pharmaceuticals reported that Chief Executive Officer and director Daniel Joseph O’Connell received a new equity compensation package on January 20, 2026, consisting of an RSU award of 299,800 shares of Common Stock and an employee stock option covering 450,000 shares.

How many Acumen Pharmaceuticals (ABOS) RSUs were granted to the CEO and how do they vest?

Daniel Joseph O’Connell received 299,800 restricted stock units (RSUs). Each RSU represents a right to one share of Common Stock. The RSUs vest in three equal annual installments, beginning one year after the grant date, as long as he continues to provide service through each vesting date.

What are the terms of the stock options granted to the Acumen Pharmaceuticals (ABOS) CEO?

The CEO was granted an employee stock option for 450,000 shares of Common Stock with an exercise price of $1.86 per share. These options vest in 48 equal monthly installments so that they are fully vested on the fourth anniversary of the January 20, 2026 grant date, subject to his continuous service.

How many Acumen Pharmaceuticals (ABOS) shares does the CEO hold after the RSU grant?

After the reported RSU transaction, Daniel Joseph O’Connell beneficially owns 893,310 shares of Acumen Pharmaceuticals Common Stock directly. This figure reflects his holdings following the January 20, 2026 RSU award of 299,800 shares at a price of $0.

How many Acumen Pharmaceuticals (ABOS) stock options does the CEO hold after the latest grant?

Following the January 20, 2026 grant, the Form 4 shows that Daniel Joseph O’Connell directly holds 450,000 employee stock options tied to Acumen Pharmaceuticals Common Stock. These options have an exercise price of $1.86 per share and follow a four-year vesting schedule.

Is the Acumen Pharmaceuticals (ABOS) CEO both a director and an officer of the company?

Yes. The Form 4 identifies Daniel Joseph O’Connell as both a director and an officer of Acumen Pharmaceuticals, serving as the company’s Chief Executive Officer, and indicates that the filing is made by one reporting person.