Acrivon insiders report RSU tax withholding; CEO retains 2.13M shares

Rhea-AI Filing Summary

Acrivon Therapeutics insiders reported an internal share disposition related to restricted stock unit vesting. On 08/21/2025, President and CEO Dr. Peter Blume-Jensen had 19,905 common shares dispositioned at $1.32 per share; the filing states these shares were withheld by the issuer to satisfy mandatory tax withholding on vested restricted stock units. After the transaction Dr. Blume-Jensen is reported to beneficially own 2,126,440 shares (direct). The filing also shows 315,196 common shares held indirectly by EVP Dr. Kristina Masson. Both reporting persons are officers and directors and are spouses; each disclaims beneficial ownership of the other’s holdings except to the extent of pecuniary interest. The Form 4 is signed by an attorney-in-fact on behalf of both reporting persons.

Positive

• Timely, compliant disclosure: Form 4 provides required transaction details and was signed by attorney-in-fact.
• Non-market disposition: 19,905 shares were withheld by the issuer to satisfy tax withholding for vested RSUs, not an open-market sale.
• Material ownership disclosed: CEO retains 2,126,440 direct shares; EVP holds 315,196 indirect shares.

Negative

• Insider disposition recorded: 19,905 shares were disposed at $1.32, which reduces reported direct holdings by that amount.
• Potential concentration: Large reported insider holdings may imply significant insider exposure to company equity.

Insights

Securities Analyst

TL;DR: A routine RSU vesting withholding resulted in a reported disposition; no open-market sale is shown.

The Form 4 documents a non-market disposition of 19,905 shares by the CEO on 08/21/2025 at $1.32 per share, explicitly attributed to issuer withholding for tax obligations on vested restricted stock units. That distinction matters because withheld shares do not represent an active sale by the insider to third parties. Reported direct beneficial ownership for the CEO remains material at 2,126,440 shares, and the EVP holds 315,196 indirectly. For investors this is a transparency event rather than a disclosed change in trading intent or portfolio reallocation.

Corporate Governance Expert

TL;DR: Filing shows standard insider reporting and proper disclosure of spousal holdings and disclaimers.

The Form 4 includes clear footnotes: withheld shares were used to meet tax withholding on RSU vesting and both officers disclose spousal relationship and reciprocal disclaimers of beneficial ownership except for pecuniary interest. The filing is signed by an attorney-in-fact and presents required details such as transaction date, price, and post-transaction holdings. From a governance perspective this reflects compliance with Section 16 reporting obligations and appropriate disclosure of indirect holdings.

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

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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^*

Blume-Jensen Peter

(Last) (First) (Middle)

C/O ACRIVON THERAPEUTICS, INC.

480 ARSENAL WAY, SUITE 100

(Street)

WATERTOWN MA 02472

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Acrivon Therapeutics, Inc. [ ACRV ]

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

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

3. Date of Earliest Transaction (Month/Day/Year)
08/21/2025

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

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

	Form filed by One Reporting Person
X	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	08/21/2025		F(1)		19,905	D	$1.32	2,126,440	D(2)
Common Stock								315,196	I	See Footnote(3)

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

1. Name and Address of Reporting Person^*

Blume-Jensen Peter

(Last) (First) (Middle)

C/O ACRIVON THERAPEUTICS, INC.

480 ARSENAL WAY, SUITE 100

(Street)

WATERTOWN MA 02472

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

1. Name and Address of Reporting Person^*

Masson Kristina

(Last) (First) (Middle)

C/O ACRIVON THERAPEUTICS, INC.

480 ARSENAL WAY, SUITE 100

(Street)

WATERTOWN MA 02472

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP - Business Operations

Explanation of Responses:

1. Shares withheld by the Issuer to satisfy the mandatory tax withholding requirement upon vesting of restricted stock units.

2. These securities are held by President and CEO, Dr. Peter Blume-Jensen, who is also Dr. Kristina Masson's spouse. Dr. Masson disclaims beneficial ownership of such securities except to the extent of her pecuniary interest therein.

3. These securities are held by co-founder and EVP, Dr. Kristina Masson, who is also Dr. Blume-Jensen's spouse. Dr. Blume-Jensen disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

	/s/ Mary-Alice Miller, Attorney-in-Fact for Peter Blume-Jensen	08/25/2025
	/s/ Mary-Alice Miller, Attorney-in-Fact for Kristina Masson	08/25/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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FAQ

What did ACRV insiders report on the Form 4 filed for 08/21/2025?

The filing reports that CEO Dr. Peter Blume-Jensen had 19,905 common shares dispositioned at $1.32 on 08/21/2025, withheld by the issuer to satisfy tax withholding on vested RSUs.

Does the Form 4 show an open-market sale by the CEO of ACRV?

No. The Form 4 states the 19,905-share disposition was due to issuer withholding to satisfy mandatory tax withholding on vested restricted stock units, not an open-market sale.

How many ACRV shares do the reporting insiders beneficially own after the transaction?

The CEO is reported to beneficially own 2,126,440 shares (direct). The EVP, Dr. Kristina Masson, holds 315,196 shares indirectly.

Are the reporting persons related or connected?

Yes. The filing discloses that Dr. Peter Blume-Jensen and Dr. Kristina Masson are spouses and each disclaims beneficial ownership of the other’s securities except for pecuniary interest.

Who signed the Form 4 for the reporting persons?

The Form 4 was signed on behalf of both reporting persons by Mary-Alice Miller, Attorney-in-Fact on 08/25/2025.