<SEC-DOCUMENT>0001380106-25-000039.txt : 20250220
<SEC-HEADER>0001380106-25-000039.hdr.sgml : 20250220
<ACCEPTANCE-DATETIME>20250220190343
ACCESSION NUMBER:		0001380106-25-000039
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250218
FILED AS OF DATE:		20250220
DATE AS OF CHANGE:		20250220

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Wilson John J. Addington
		CENTRAL INDEX KEY:			0001872301
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-40592
		FILM NUMBER:		25647944

	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
		IRS NUMBER:				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_1740096216.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-02-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001380106</issuerCik>
        <issuerName>RAPID MICRO BIOSYSTEMS, INC.</issuerName>
        <issuerTradingSymbol>RPID</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001872301</rptOwnerCik>
            <rptOwnerName>Wilson John J. Addington</rptOwnerName>
        </reportingOwnerId>
        <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>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CHIEF OPERATING OFFICER</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-02-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>44000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>242346</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.90</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-02-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>89000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2035-02-17</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>89000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>89000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Grant of restricted stock units (&quot;RSUs&quot;) that vest in three annual installments with 33.4% vesting on the first anniversary of February 18, 2025 (the &quot;grant date&quot;) and 33.3% vesting on each of the second and third anniversaries of the grant date provided that the Reporting Person remains in continuous service on each vesting date.</footnote>
        <footnote id="F2">The option vests and becomes exercisable in 48 substantially equal monthly installments with the first installment vesting on March 18, 2025.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Sean M. Wirtjes, Attorney-in-Fact for John J. Addington Wilson</signatureName>
        <signatureDate>2025-02-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
