<SEC-DOCUMENT>0001453687-23-000085.txt : 20231115
<SEC-HEADER>0001453687-23-000085.hdr.sgml : 20231115
<ACCEPTANCE-DATETIME>20231115171816
ACCESSION NUMBER:		0001453687-23-000085
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20231113
FILED AS OF DATE:		20231115
DATE AS OF CHANGE:		20231115

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ZENNER PATRICK J
		CENTRAL INDEX KEY:			0001139036
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37798
		FILM NUMBER:		231411591

	MAIL ADDRESS:	
		STREET 1:		C/O DENDRITE INTERNATIONAL INC.
		STREET 2:		1405/1425 ROUTE 206 SOUTH
		CITY:			BEDMINSTER
		STATE:			NJ
		ZIP:			07921

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Cartesian Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001453687
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		65 GROVE STREET
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02472
		BUSINESS PHONE:		617-923-1400

	MAIL ADDRESS:	
		STREET 1:		65 GROVE STREET
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02472

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SELECTA BIOSCIENCES INC
		DATE OF NAME CHANGE:	20090109
</SEC-HEADER>
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    <footnotes>
        <footnote id="F1">This option, which provided for vesting in thirty-six (36) substantially equal monthly installments over three years following the date of grant on June 16, 2017, was canceled in the merger (the &quot;Merger&quot;) between Selecta Biosciences, Inc. and Cartesian Therapeutics, Inc.</footnote>
        <footnote id="F2">This option, which provided for vesting in full on June 13, 2019, was canceled in the Merger.</footnote>
        <footnote id="F3">This option, which provided for vesting in full on June 14, 2020, was canceled in the Merger.</footnote>
        <footnote id="F4">This option, which provided for vesting in full on June 17, 2021, was canceled in the Merger.</footnote>
        <footnote id="F5">This option, which provided for vesting in full on March 30, 2022, was canceled in the Merger.</footnote>
        <footnote id="F6">This option, which provided for vesting in full on January 3, 2023, was canceled in the Merger.</footnote>
        <footnote id="F7">This option, which provided for vesting in full on January 2, 2024, was canceled in the Merger in exchange for a cash payment of $69,750, representing the difference between the exercise price of the option and $2.06, the Cash-out Amount as applied in the Merger.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Matthew Bartholomae, Attorney-in-Fact for Patrick Zenner</signatureName>
        <signatureDate>2023-11-15</signatureDate>
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