<SEC-DOCUMENT>0001140361-25-010078.txt : 20250324
<SEC-HEADER>0001140361-25-010078.hdr.sgml : 20250324
<ACCEPTANCE-DATETIME>20250324183427
ACCESSION NUMBER:		0001140361-25-010078
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250321
FILED AS OF DATE:		20250324
DATE AS OF CHANGE:		20250324

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Keyes Jeffry R.
		CENTRAL INDEX KEY:			0001557736
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39486
		FILM NUMBER:		25765348

	MAIL ADDRESS:	
		STREET 1:		13950 STOWE DRIVE
		CITY:			POWAY
		STATE:			CA
		ZIP:			92064-8803

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Quantum-Si Inc
		CENTRAL INDEX KEY:			0001816431
		STANDARD INDUSTRIAL CLASSIFICATION:	MEASURING & CONTROLLING DEVICES, NEC [3829]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		EIN:				851388175
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		29 BUSINESS PARK DRIVE
		CITY:			BRANFORD
		STATE:			CT
		ZIP:			06405
		BUSINESS PHONE:		(203) 458-7100

	MAIL ADDRESS:	
		STREET 1:		29 BUSINESS PARK DRIVE
		CITY:			BRANFORD
		STATE:			CT
		ZIP:			06405

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HighCape Capital Acquisition Corp.
		DATE OF NAME CHANGE:	20200629
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-03-21</periodOfReport>

    <issuer>
        <issuerCik>0001816431</issuerCik>
        <issuerName>Quantum-Si Inc</issuerName>
        <issuerTradingSymbol>QSI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001557736</rptOwnerCik>
            <rptOwnerName>Keyes Jeffry R.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O QUANTUM-SI INCORPORATED</rptOwnerStreet1>
            <rptOwnerStreet2>29 BUSINESS PARK DRIVE</rptOwnerStreet2>
            <rptOwnerCity>BRANFORD</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06405</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>true</isOfficer>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-03-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>8626</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.3855</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1188194</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares sold pursuant to a mandatory Quantum-Si sell-to-cover provision for required federal, state and local withholding taxes in connection with the vesting of previously granted restricted stock units.  Individual is not able to alter this mandatory sell-to-cover provision that is enacted at the grant date of the related restricted stock unit award.</footnote>
        <footnote id="F2">Represents the weighted average sales price per share. The shares sold at prices ranging from $1.36 to $1.405 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Christian LaPointe, Ph.D., Attorney-in-Fact.</signatureName>
        <signatureDate>2025-03-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
