[Form 4] HilleVax, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Robert Hershberg, President, CEO and director of HilleVax, Inc. (HLVX), reported a disposition of 1,101,498 shares of Common Stock on 09/17/2025. The filing states this transaction occurred in connection with an Agreement and Plan of Merger dated August 4, 2025, under which XOMA Royalty Corporation completed a tender offer and acquired all outstanding HilleVax shares.

Under the deal, former public shareholders received $1.95 cash per share plus one contingent value right (CVR) tied to potential future cash payments. At the effective time, Merger Sub merged into HilleVax, which continues as a wholly owned subsidiary of the purchaser.

Positive

• Merger closed with all outstanding shares acquired, providing liquidity to shareholders at $1.95 per share
• Contingent value right (CVR) preserves potential future cash upside for former shareholders

Negative

• Reporting person disposed of 1,101,498 shares, eliminating reported direct beneficial ownership following the transaction
• Company is now a wholly owned subsidiary of XOMA Royalty Corporation, removing HilleVax from public equity markets

Insights

Financial Analyst

TL;DR: Insider sold all reported shares due to completed merger that paid $1.95 per share plus a CVR, converting public equity to takeover consideration.

The Form 4 discloses a full or near-full disposition by the reporting person tied directly to the merger closing. The cash consideration of $1.95 per share is the explicit liquidation price for holders, supplemented by a CVR that preserves limited contingent upside. For investors, this is a liquidity event that removes a public float and consolidates ownership under XOMA Royalty Corporation. There is no earnings or operational information in the filing to assess business performance; the filing documents transaction mechanics only.

M&A Specialist

TL;DR: Transaction reflects a completed acquisition structure: tender offer followed by merger, with cash plus CVR consideration.

The disclosed sequence—tender offer then short-form merger effective 09/17/2025—is a standard acquisition closing path. The inclusion of a CVR indicates the buyers allocated some purchase consideration to contingent future events rather than all-upfront cash. The filing confirms HilleVax now operates as a wholly owned subsidiary of the acquirer, which is material to corporate control and governance. The Form 4 documents the change in beneficial ownership without providing post-close integration or synergy details.

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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X

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

1. Name and Address of Reporting Person^*

HERSHBERG ROBERT

(Last) (First) (Middle)

C/O HILLEVAX, INC.

321 HARRISON AVE, SUITE 500

(Street)

BOSTON MA 02118

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
HilleVax, Inc. [ HLVX ]

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)
09/17/2025

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	09/17/2025		U		1,101,498	D	(1)	0	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. In connection with that certain Agreement and Plan of Merger, dated as of August 4, 2025 (the "Merger Agreement"), by and among the Issuer, XOMA Royalty Corporation ("Parent") and XRA 4 Corp., a wholly owned subsidiary of Parent ("Merger Sub" and together with Parent, the "Purchasers"), the Purchasers completed a tender offer to acquire all of the issued and outstanding shares of Common Stock of the Issuer in exchange for (a) $1.95 in cash per share (the "Cash Amount"), plus (b) one contingent value right ("CVR") representing the right to receive certain contingent cash payments equal to the "CVR Proceeds" as further described in that certain CVR Agreement entered into between the Purchasers and a representative to the CVR holders. After completion of the tender offer, Merger Sub merged with and into the Issuer, effective as of September 17, 2025 (the "Effective Time"), with the Issuer continuing as the surviving corporation and as a wholly owned subsidiary of Parent.

	/s/ Paul Bavier, Attorney-in-Fact for Robert Hershberg	09/17/2025
	** 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 Robert Hershberg report in the Form 4 for HLVX?

The filing reports a disposition of 1,101,498 shares on 09/17/2025, executed in connection with the merger and tender offer.

What consideration did HilleVax shareholders receive in the acquisition?

Shareholders received $1.95 in cash per share plus one CVR entitling them to certain contingent cash payments as described in the CVR Agreement.

Who acquired HilleVax and how was the acquisition completed?

XOMA Royalty Corporation (through its subsidiary XRA 4 Corp.) completed a tender offer and merged Merger Sub with HilleVax, effective 09/17/2025.

Does the Form 4 disclose any remaining HilleVax shares owned by the reporting person?

The Form 4 reports 0 shares beneficially owned by the reporting person following the reported disposition.

Was the disposition voluntary open-market trading or part of the acquisition process?

The filing links the disposition to the Merger Agreement and the completed tender offer, indicating it was part of the acquisition process.