Zenas BioPharma (ZBIO) CEO boosts stake with 57,000-share purchase

Rhea-AI Filing Summary

Zenas BioPharma, Inc.’s chief executive officer and chairman, Leon O. Moulder, Jr., purchased 57,000 shares of common stock on February 2, 2026 at a weighted average price of $17.96 per share, in multiple trades between $17.69 and $18.14.

Following this transaction, he directly holds 423,155 common shares. A revocable trust associated with him holds 36,928 shares, and Tellus BioVentures LLC holds 1,672,039 shares; he may be deemed to have voting and dispositive power over these but disclaims beneficial ownership except for his pecuniary interest.

Insider Trade Summary

Net Buyer: 57,000 shares ($1,023,720)

Net Buy 3 txns

Insider MOULDER LEON O JR

Role Chief Executive Officer

Bought 57,000 shs ($1.02M)

Type	Security	Shares	Price	Value
Purchase	Common Stock	57,000	$17.96	$1.02M
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 423,155 shares (Direct); Common Stock — 36,928 shares (Indirect, See Footnote)

Footnotes (1)

1. The price reported is a weighted average price. These shares were purchased in multiple transactions ranging from $17.69 to $18.14, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range. The reporting person is a Trustee of the Leon O. Moulder, Jr. Revocable Trust U/A dtd 9/9/2008 (the "Trust") and may be deemed to have voting and dispositive power over the shares held by the Trust. The reporting person is the Issuer's chief executive officer and Chairman of its board of directors. The reporting person disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein. Leon O. Moulder, Jr. is the Managing Member of Tellus BioVentures LLC ("Tellus") and may be deemed to have sole voting and dispositive power over the shares held by Tellus. Mr. Moulder is the Issuer's chief executive officer and Chairman of its board of directors. Mr. Moulder disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

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^*

MOULDER LEON O JR

(Last) (First) (Middle)

C/O ZENAS BIOPHARMA, INC.

852 WINTER STREET, SUITE 250

(Street)

WALTHAM MA 02451

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Zenas BioPharma, Inc. [ ZBIO ]

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)
02/02/2026

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	02/02/2026		P		57,000	A	$17.96(1)	423,155	D
Common Stock								36,928	I	See Footnote(2)
Common Stock								1,672,039	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

Explanation of Responses:

1. The price reported is a weighted average price. These shares were purchased in multiple transactions ranging from $17.69 to $18.14, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range.

2. The reporting person is a Trustee of the Leon O. Moulder, Jr. Revocable Trust U/A dtd 9/9/2008 (the "Trust") and may be deemed to have voting and dispositive power over the shares held by the Trust. The reporting person is the Issuer's chief executive officer and Chairman of its board of directors. The reporting person disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

3. Leon O. Moulder, Jr. is the Managing Member of Tellus BioVentures LLC ("Tellus") and may be deemed to have sole voting and dispositive power over the shares held by Tellus. Mr. Moulder is the Issuer's chief executive officer and Chairman of its board of directors. Mr. Moulder disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

	By: /s/ Chase Jayasekera, Attorney-in-Fact	02/03/2026
	** 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 Zenas BioPharma (ZBIO) report?

Zenas BioPharma reported that CEO and chairman Leon O. Moulder, Jr. bought 57,000 common shares. The shares were acquired on February 2, 2026 at a weighted average price of $17.96 per share, in multiple trades across a narrow intraday price range.

At what prices did the Zenas BioPharma (ZBIO) CEO buy his shares?

The CEO’s 57,000-share purchase was executed at a weighted average price of $17.96. According to the disclosure, individual trades occurred in a range from $17.69 to $18.14 per share, with full trade-by-trade details available to investors on request.

How many Zenas BioPharma (ZBIO) shares does the CEO now hold directly?

After the reported purchase, Leon O. Moulder, Jr. directly holds 423,155 shares of Zenas BioPharma common stock. This figure reflects his personal direct ownership and excludes additional shares held through related entities, which are reported separately as indirect holdings in the filing.

What Zenas BioPharma (ZBIO) shares are held through the Leon O. Moulder, Jr. Revocable Trust?

The revocable trust associated with Leon O. Moulder, Jr. holds 36,928 Zenas BioPharma common shares. He serves as trustee and may be deemed to have voting and dispositive power, while disclaiming beneficial ownership of those securities except to the extent of his pecuniary interest.

What role does Tellus BioVentures LLC play in Zenas BioPharma (ZBIO) ownership?

Tellus BioVentures LLC holds 1,672,039 Zenas BioPharma common shares as an indirect owner. Leon O. Moulder, Jr. is the managing member and may be deemed to have sole voting and dispositive power, while disclaiming beneficial ownership except for his economic interest in those securities.

Who is the insider involved in the latest Zenas BioPharma (ZBIO) Form 4?

The insider is Leon O. Moulder, Jr., Zenas BioPharma’s chief executive officer, chairman of the board and a director. The Form 4 details his direct purchase of common stock and reports additional indirect holdings through a revocable trust and Tellus BioVentures LLC.