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    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001951176</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
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    <issuerInfo>
      <issuerCik>0000859737</issuerCik>
      <issuerName>HOLOGIC INC</issuerName>
      <secFileNumber>001-36214</secFileNumber>
      <issuerAddress>
        <com:street1>250 CAMPUS DRIVE</com:street1>
        <com:city>MARLBOROUGH</com:city>
        <com:stateOrCountry>MA</com:stateOrCountry>
        <com:zipCode>01752</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>5082632900</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Mitchell Essex D</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Fidelity Brokerage Services LLC</name>
        <address>
          <com:street1>900 Salem Street</com:street1>
          <com:city>Smithfield</com:city>
          <com:stateOrCountry>RI</com:stateOrCountry>
          <com:zipCode>02917</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>2390</noOfUnitsSold>
      <aggregateMarketValue>200115.49</aggregateMarketValue>
      <noOfUnitsOutstanding>246118192</noOfUnitsOutstanding>
      <approxSaleDate>05/05/2023</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/11/2022</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>662</amountOfSecuritiesAcquired>
      <paymentDate>11/11/2022</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>06/30/2022</acquiredDate>
      <natureOfAcquisitionTransaction>ESPP Purchase</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>22</amountOfSecuritiesAcquired>
      <paymentDate>06/30/2022</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/30/2022</acquiredDate>
      <natureOfAcquisitionTransaction>ESPP Purchase</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>147</amountOfSecuritiesAcquired>
      <paymentDate>12/30/2022</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/12/2021</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>36</amountOfSecuritiesAcquired>
      <paymentDate>11/12/2021</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/31/2021</acquiredDate>
      <natureOfAcquisitionTransaction>ESPP Purchase</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>144</amountOfSecuritiesAcquired>
      <paymentDate>12/31/2021</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/09/2022</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>530</amountOfSecuritiesAcquired>
      <paymentDate>11/09/2022</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/08/2022</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>849</amountOfSecuritiesAcquired>
      <paymentDate>11/08/2022</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>05/05/2023</noticeDate>
      <signature>/s/ Jennifer Ruchti, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Essex D. Mitchell</signature>
    </noticeSignature>
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144
0001951176
XXXXXXXX
LIVE
0000859737
HOLOGIC INC
001-36214
250 CAMPUS DRIVE
MARLBOROUGH
MA
01752
5082632900
Mitchell Essex D
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
2390
200115.49
246118192
05/05/2023
NASDAQ
Common
11/11/2022
Restricted Stock Vesting
Issuer
N
662
11/11/2022
Compensation
Common
06/30/2022
ESPP Purchase
Issuer
N
22
06/30/2022
Cash
Common
12/30/2022
ESPP Purchase
Issuer
N
147
12/30/2022
Cash
Common
11/12/2021
Restricted Stock Vesting
Issuer
N
36
11/12/2021
Compensation
Common
12/31/2021
ESPP Purchase
Issuer
N
144
12/31/2021
Cash
Common
11/09/2022
Restricted Stock Vesting
Issuer
N
530
11/09/2022
Compensation
Common
11/08/2022
Restricted Stock Vesting
Issuer
N
849
11/08/2022
Compensation
Y
05/05/2023
/s/ Jennifer Ruchti, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Essex D. Mitchell