<SEC-DOCUMENT>0001104659-24-100333.txt : 20240916
<SEC-HEADER>0001104659-24-100333.hdr.sgml : 20240916
<ACCEPTANCE-DATETIME>20240916205732
ACCESSION NUMBER:		0001104659-24-100333
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240912
FILED AS OF DATE:		20240916
DATE AS OF CHANGE:		20240916

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ENRIGHT PATRICK G
		CENTRAL INDEX KEY:			0001253886
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-42270
		FILM NUMBER:		241302350

	MAIL ADDRESS:	
		STREET 1:		CO LONGITUDE CAPITAL PARTNERS LLC
		STREET 2:		800 EL CAMINO REAL, SUITE 220
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Zenas BioPharma, Inc.
		CENTRAL INDEX KEY:			0001953926
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1000 WINTER ST, SUITE 1200
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		857-271-2954

	MAIL ADDRESS:	
		STREET 1:		1000 WINTER ST, SUITE 1200
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Zenas BioPharma (Cayman) Ltd
		DATE OF NAME CHANGE:	20221108
</SEC-HEADER>
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    <footnotes>
        <footnote id="F1">On September 16, 2024, the shares of Series B Convertible Preferred Stock automatically converted into shares of Common Stock on a 8.6831-for-1 basis without payment of further consideration upon the closing of the Issuer's initial public offering. The shares have no expiration date.</footnote>
        <footnote id="F2">Shares held by Longitude Venture Partners IV, L.P. (&quot;LVPIV&quot;).</footnote>
        <footnote id="F3">Longitude Capital Partners IV, LLC (&quot;LCPIV&quot;) is the general partner of LVPIV and may be deemed to have voting, investment and dispositive power with respect to these securities. Longitude Prime Partners, LLC (&quot;LPP&quot;) is the general partner of Longitude Prime Fund, L.P. (&quot;LPF&quot;) and may be deemed to have voting, investment and dispositive power with respect to the securities held by LPF. Juliet Tammenoms Bakker and Patrick G. Enright, a member of the board of directors of the Issuer, are the managing members of LCPIV and LPP and may each be deemed to share voting, investment and dispositive power with respect to these securities. Each of LCPIV, LPP, Ms. Bakker and Mr. Enright disclaims beneficial ownership of such securities except to the extent of their respective pecuniary interests therein.</footnote>
        <footnote id="F4">On September 16, 2024, the shares of Series C Convertible Preferred Stock automatically converted into shares of Common Stock on a 8.6831-for-1 basis without payment of further consideration upon the closing of the Issuer's initial public offering. The shares have no expiration date.</footnote>
        <footnote id="F5">Shares held by LPF.</footnote>
        <footnote id="F6">The option vests in equal annual installments over three years beginning on September 12, 2025, the first anniversary of the vesting commencement date, subject to continued service.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ Chase Jayasekera, Attorney-in-Fact</signatureName>
        <signatureDate>2024-09-16</signatureDate>
    </ownerSignature>
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