<SEC-DOCUMENT>0001557736-26-000001.txt : 20260324
<SEC-HEADER>0001557736-26-000001.hdr.sgml : 20260324
<ACCEPTANCE-DATETIME>20260324091058
ACCESSION NUMBER:		0001557736-26-000001
CONFORMED SUBMISSION TYPE:	144
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20260324
DATE AS OF CHANGE:		20260324

SUBJECT COMPANY:	

	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

	FILING VALUES:
		FORM TYPE:		144
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	001-39486
		FILM NUMBER:		26784349

	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

REPORTING-OWNER:	

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

	FILING VALUES:
		FORM TYPE:		144

	MAIL ADDRESS:	
		STREET 1:		13950 STOWE DRIVE
		CITY:			POWAY
		STATE:			CA
		ZIP:			92064-8803
</SEC-HEADER>
<DOCUMENT>
<TYPE>144
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
  <headerData>
    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001557736</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>


    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0001816431</issuerCik>
      <issuerName>Quantum-Si Inc</issuerName>
      <secFileNumber>001-39486</secFileNumber>
      <issuerAddress>
        <com:street1>29 BUSINESS PARK DRIVE</com:street1>
        <com:city>BRANFORD</com:city>
        <com:stateOrCountry>CT</com:stateOrCountry>
        <com:zipCode>06405</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>(203) 458-7100</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Keyes Jeffry R.</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Morgan Stanley Smith Barney LLC</name>
        <address>
          <com:street1>1 New York Plaza</com:street1>
          <com:street2>38th Floor</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10004</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>8655</noOfUnitsSold>
      <aggregateMarketValue>7246.08</aggregateMarketValue>
      <noOfUnitsOutstanding>196431273</noOfUnitsOutstanding>
      <approxSaleDate>03/20/2026</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <acquiredDate>03/15/2024</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Unit Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Quantum-Si Incorporated</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>21676</amountOfSecuritiesAcquired>
      <paymentDate>03/15/2024</paymentDate>
      <natureOfPayment>Equity compensation for services rendered</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Morgan Stanley Smith Barney LLC</name>
        <address>
          <com:street1>1 New York Plaza</com:street1>
          <com:street2>38th Floor</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10004</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>12/22/2025</saleDate>
      <amountOfSecuritiesSold>8627</amountOfSecuritiesSold>
      <grossProceeds>11008.05</grossProceeds>
    </securitiesSoldInPast3Months>
    <remarks>Shares sold to cover tax withholding obligations in connection with the vesting of restricted stock units. The sale is mandated by the Issuers election to require the satisfaction of tax withholding obligations through a sell to cover transaction and does not represent a discretionary trade by the reporting person.</remarks>
    <noticeSignature>
      <noticeDate>03/24/2026</noticeDate>
      <signature>/s/ Christian LaPointe, Ph.D., Attorney-in-Fact</signature>
    </noticeSignature>
  </formData>
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</SEC-DOCUMENT>
