<SEC-DOCUMENT>0001453687-24-000132.txt : 20241118
<SEC-HEADER>0001453687-24-000132.hdr.sgml : 20241118
<ACCEPTANCE-DATETIME>20241118193236
ACCESSION NUMBER:		0001453687-24-000132
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20241114
FILED AS OF DATE:		20241118
DATE AS OF CHANGE:		20241118

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Kurtoglu Metin
		CENTRAL INDEX KEY:			0002000284
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37798
		FILM NUMBER:		241472983

	MAIL ADDRESS:	
		STREET 1:		C/O CARTESIAN THERAPEUTICS, INC.
		STREET 2:		704 QUINCE ORCHARD RD
		CITY:			GAITHERSBURG
		STATE:			MD
		ZIP:			20878

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Cartesian Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001453687
		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:		7495 NEW HORIZON WAY
		CITY:			FREDERICK
		STATE:			MD
		ZIP:			21703
		BUSINESS PHONE:		301-348-8698

	MAIL ADDRESS:	
		STREET 1:		7495 NEW HORIZON WAY
		CITY:			FREDERICK
		STATE:			MD
		ZIP:			21703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SELECTA BIOSCIENCES INC
		DATE OF NAME CHANGE:	20090109
</SEC-HEADER>
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    <footnotes>
        <footnote id="F1">The price reported is a weighted average price. The shares were sold in multiple transactions at per share prices ranging from $16.00 to $16.65. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F2">The price reported is a weighted average price. The shares were sold in multiple transactions at per share prices ranging from $17.00 to $17.12. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F3">The price reported is a weighted average price. The shares were sold in multiple transactions at per share prices ranging from $17.00 to $17.42. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F4">The price reported is a weighted average price. The shares were sold in multiple transactions at per share prices ranging from $17.50 to $18.49. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F5">The price reported is a weighted average price. The shares were sold in multiple transactions at per share prices ranging from $18.50 to $18.69. The Reporting Person undertakes to provide upon request to the SEC staff, the Issuer, or any stockholder of the Issuer, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F6">The option was fully vested and exercisable upon the closing of the merger described in footnote 7.</footnote>
        <footnote id="F7">On November 13, 2023, the Issuer acquired the private Delaware corporation which was then known as Cartesian Therapeutics, Inc. (&quot;Old Cartesian&quot;) in accordance with the terms of an Agreement
and Plan of Merger, dated November 13, 2023. Options to purchase Old Cartesian common stock held by the reporting person were converted into options to purchase shares of the Issuer's Series A
Preferred Stock in connection with the merger. On April 8, 2024, these options previously exercisable for shares of Series A Preferred Stock became exercisable solely for shares of the Issuer's Common
Stock.</footnote>
    </footnotes>

    <remarks></remarks>

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        <signatureName>/s/ Matthew Bartholomae, Attorney-in-Fact for Metin Kurtoglu</signatureName>
        <signatureDate>2024-11-18</signatureDate>
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