Moulder Leon O Jr. - 18 May 2026 Form 4 Insider Report for Zenas BioPharma, Inc. (ZBIO)

Reporting relationship: Chief Executive Officer, Director
Issuer ticker: ZBIO
Reported as of: 18 May 2026
Net transaction value: +$1,012,800
SEC form: 4
Accepted by SEC: 18 May 2026, 21:12:28 UTC
Prior SEC filing: 29 Apr 2026
Next SEC filing: 17 Jun 2026
Source filing: View source filing
Reporting owner signature: By: /s/ Chase Jayasekera, Attorney-in-Fact

Key filing fact

Moulder Leon O Jr. filed Form 4 for Zenas BioPharma, Inc. (ZBIO) on 18 May 2026.

Key facts

This page summarizes Moulder Leon O Jr.'s Form 4 filing for Zenas BioPharma, Inc. (ZBIO).
1 reported transaction and 0 derivative rows are listed below.
Accepted by SEC: 18 May 2026, 21:12.

Change

Previous filing in this sequence was filed on 29 Apr 2026.
Current net transaction value: +$1,012,800.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001228865 Primary reporting owner

MOULDER LEON O JR

Relationship: Chief Executive Officer, Director
Address: C/O ZENAS BIOPHARMA, INC., 852 WINTER STREET, SUITE 250, WALTHAM
Signature: By: /s/ Chase Jayasekera, Attorney-in-Fact
Signature date: 18 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

ZBIO transaction

Common Stock

Purchase

Transaction value: $1,012,800
Shares: +60,000
Change %: +162%
Price: $16.88
Shares after: 96,928
Date: 18 May 2026
Ownership: See Footnote
Footnotes: F1, F2

ZBIO holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 1,786,039
Date: 18 May 2026
Ownership: See Footnote
Footnotes: F3

ZBIO holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 423,155
Date: 18 May 2026
Ownership: Direct

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

The price reported is a weighted average price. These shares were purchased in multiple transactions ranging from $16.59 to $16.97, 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.

Footnote F2

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.

Footnote F3

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. The reporting person disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.