<SEC-DOCUMENT>0001380106-25-000157.txt : 20250710
<SEC-HEADER>0001380106-25-000157.hdr.sgml : 20250710
<ACCEPTANCE-DATETIME>20250710194321
ACCESSION NUMBER:		0001380106-25-000157
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250708
FILED AS OF DATE:		20250710
DATE AS OF CHANGE:		20250710

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Spignesi Robert G. Jr.
		CENTRAL INDEX KEY:			0001853904
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-40592
		FILM NUMBER:		251117319

	MAIL ADDRESS:	
		STREET 1:		C/O RAPID MICRO BIOSYSTEMS, INC.
		STREET 2:		1001 PAWTUCKET BOULEVARD WEST, SUITE 280
		CITY:			LOWELL
		STATE:			MA
		ZIP:			01854

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RAPID MICRO BIOSYSTEMS, INC.
		CENTRAL INDEX KEY:			0001380106
		STANDARD INDUSTRIAL CLASSIFICATION:	LABORATORY ANALYTICAL INSTRUMENTS [3826]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		EIN:				208121647
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		25 HARTWELL AVENUE
		CITY:			LEXINGTON
		STATE:			MA
		ZIP:			02421
		BUSINESS PHONE:		978-349-3200

	MAIL ADDRESS:	
		STREET 1:		25 HARTWELL AVENUE
		CITY:			LEXINGTON
		STATE:			MA
		ZIP:			02421

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	RAPID MICRO BIOSYSTEMS INC
		DATE OF NAME CHANGE:	20061103
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1752190995.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2025-07-08</periodOfReport>

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    <issuer>
        <issuerCik>0001380106</issuerCik>
        <issuerName>RAPID MICRO BIOSYSTEMS, INC.</issuerName>
        <issuerTradingSymbol>RPID</issuerTradingSymbol>
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        <reportingOwnerId>
            <rptOwnerCik>0001853904</rptOwnerCik>
            <rptOwnerName>Spignesi Robert G. Jr.</rptOwnerName>
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        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O RAPID MICRO BIOSYSTEMS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>25 HARTWELL AVENUE</rptOwnerStreet2>
            <rptOwnerCity>LEXINGTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02421</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>PRESIDENT AND CEO</officerTitle>
            <otherText></otherText>
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    </reportingOwner>

    <aff10b5One>0</aff10b5One>

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                <transactionCode>M</transactionCode>
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                <transactionPricePerShare>
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                    <footnoteId id="F2"/>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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                <value>Class A Common Stock</value>
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                    <value>25145</value>
                    <footnoteId id="F1"/>
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                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
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                <value>Class A Common Stock</value>
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            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>11617</value>
                    <footnoteId id="F2"/>
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                    <value>3.398</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Shares were acquired upon satisfaction of performance criteria underlying previously granted performance restricted stock units.</footnote>
        <footnote id="F2">The sales reported on this Form 4 represent shares sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of performance restricted stock units.</footnote>
        <footnote id="F3">Includes 29,904 shares acquired under the Rapid Micro Biosystems, Inc. employee stock purchase plan on March 14, 2025.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Sean M. Wirtjes, Attorney-in-Fact for Robert G. Spignesi, Jr.</signatureName>
        <signatureDate>2025-07-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
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</SEC-DOCUMENT>
