Adicet Bio (ACET) CTO reports 535 shares withheld for RSU taxes

Rhea-AI Filing Summary

Adicet Bio, Inc.’s Chief Technology Officer Don Healey reported an administrative share adjustment related to equity compensation. On 01/24/2026, 535 shares of common stock were withheld by the company at $8.44 per share to cover tax obligations from vesting restricted stock units, rather than being sold on the market. Following this transaction, Healey beneficially owns 3,452 shares of Adicet Bio common stock on a direct basis. The reported holdings also reflect a previously effected 1-for-16 reverse stock split completed on December 30, 2025, which adjusted the share counts.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Healey Don

Role Chief Technology Officer

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	535	$8.44	$5K

Holdings After Transaction: Common Stock — 3,452 shares (Direct)

Footnotes (1)

1. Represents shares withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting of restricted stock units and does not represent a sale by the Reporting Person. Reflects a 1-for-16 reverse stock split effected by the Issuer on December 30, 2025.

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
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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^*

Healey Don

(Last) (First) (Middle)

C/O ADICET BIO, INC.

131 DARTMOUTH STREET, FLOOR 3

(Street)

BOSTON MA 02116

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Adicet Bio, Inc. [ ACET ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
01/24/2026

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	01/24/2026		F(1)		535	D	$8.44	3,452(2)	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

Explanation of Responses:

1. Represents shares withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting of restricted stock units and does not represent a sale by the Reporting Person.

2. Reflects a 1-for-16 reverse stock split effected by the Issuer on December 30, 2025.

	/s/ Nick Harvey, Attorney-in-Fact	01/27/2026
	** 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 Adicet Bio (ACET) report for Don Healey?

Adicet Bio reported that Chief Technology Officer Don Healey had 535 common shares withheld on 01/24/2026 to satisfy tax obligations from vesting restricted stock units, rather than executing an open-market sale of shares.

How many Adicet Bio shares does Don Healey own after the 01/24/2026 transaction?

After the 01/24/2026 tax-withholding transaction, Don Healey beneficially owns 3,452 shares of Adicet Bio common stock. These shares are held directly and reflect prior adjustments from the company’s 1-for-16 reverse stock split effective December 30, 2025.

Was the 535-share Form 4 transaction for Adicet Bio (ACET) a sale by Don Healey?

No, the 535-share transaction was not a market sale. The shares were withheld by Adicet Bio to cover tax withholding obligations tied to vesting restricted stock units, as specifically noted, meaning no discretionary sale was executed by Don Healey.

What does the 1-for-16 reverse stock split mean for Adicet Bio (ACET) share counts?

The 1-for-16 reverse stock split means every 16 Adicet Bio shares became one share on December 30, 2025. Don Healey’s reported holdings, including the 3,452 post-transaction shares, already incorporate this reverse split adjustment to the common stock count.

What is transaction code F on the Adicet Bio (ACET) Form 4 for Don Healey?

Transaction code F indicates shares were used to pay taxes on an equity award. For Don Healey, 535 common shares were withheld by Adicet Bio at $8.44 per share to satisfy tax obligations from vesting restricted stock units, rather than being sold in the market.

What role does Don Healey hold at Adicet Bio (ACET) in this Form 4?

In this Form 4, Don Healey is identified as an officer of Adicet Bio, serving as Chief Technology Officer. The filing reflects his personal beneficial ownership in the company’s common stock after tax-related share withholding tied to restricted stock unit vesting.