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    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001783992</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <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>Thornal Kevin R</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>72041</noOfUnitsSold>
      <aggregateMarketValue>6122598.19</aggregateMarketValue>
      <noOfUnitsOutstanding>246118192</noOfUnitsOutstanding>
      <approxSaleDate>05/09/2023</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>05/09/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Options Granted 11/12/2018</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>15834</amountOfSecuritiesAcquired>
      <paymentDate>05/09/2023</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>05/09/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Options Granted 11/11/2019</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>13576</amountOfSecuritiesAcquired>
      <paymentDate>05/09/2023</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>05/09/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Options Granted 11/09/2020</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>8756</amountOfSecuritiesAcquired>
      <paymentDate>05/09/2023</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>05/09/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Options Granted 11/08/2021</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>5200</amountOfSecuritiesAcquired>
      <paymentDate>05/09/2023</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>08/11/2017</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>696</amountOfSecuritiesAcquired>
      <paymentDate>08/11/2017</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/05/2017</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>430</amountOfSecuritiesAcquired>
      <paymentDate>11/05/2017</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/01/2017</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>515</amountOfSecuritiesAcquired>
      <paymentDate>12/01/2017</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>08/11/2018</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>860</amountOfSecuritiesAcquired>
      <paymentDate>08/11/2018</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/01/2018</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1636</amountOfSecuritiesAcquired>
      <paymentDate>12/01/2018</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/12/2019</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>871</amountOfSecuritiesAcquired>
      <paymentDate>11/12/2019</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/01/2019</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1170</amountOfSecuritiesAcquired>
      <paymentDate>12/01/2019</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/11/2020</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1195</amountOfSecuritiesAcquired>
      <paymentDate>11/11/2020</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/12/2020</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1131</amountOfSecuritiesAcquired>
      <paymentDate>11/12/2020</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/01/2020</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>7269</amountOfSecuritiesAcquired>
      <paymentDate>12/01/2020</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/09/2021</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1116</amountOfSecuritiesAcquired>
      <paymentDate>11/09/2021</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/11/2021</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1195</amountOfSecuritiesAcquired>
      <paymentDate>11/11/2021</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/12/2021</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>10008</amountOfSecuritiesAcquired>
      <paymentDate>11/12/2021</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/05/2018</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>583</amountOfSecuritiesAcquired>
      <paymentDate>11/05/2018</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>05/09/2023</noticeDate>
      <signature>/s/ Lisa Gerard, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Kevin Thornal</signature>
    </noticeSignature>
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[{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 11941}]
144
0001783992
XXXXXXXX
LIVE
0000859737
HOLOGIC INC
001-36214
250 CAMPUS DRIVE
MARLBOROUGH
MA
01752
5082632900
Thornal Kevin R
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
72041
6122598.19
246118192
05/09/2023
NASDAQ
Common
05/09/2023
Options Granted 11/12/2018
Issuer
N
15834
05/09/2023
Cash
Common
05/09/2023
Options Granted 11/11/2019
Issuer
N
13576
05/09/2023
Cash
Common
05/09/2023
Options Granted 11/09/2020
Issuer
N
8756
05/09/2023
Cash
Common
05/09/2023
Options Granted 11/08/2021
Issuer
N
5200
05/09/2023
Cash
Common
08/11/2017
Restricted Stock Vesting
Issuer
N
696
08/11/2017
Compensation
Common
11/05/2017
Restricted Stock Vesting
Issuer
N
430
11/05/2017
Compensation
Common
12/01/2017
Restricted Stock Vesting
Issuer
N
515
12/01/2017
Compensation
Common
08/11/2018
Restricted Stock Vesting
Issuer
N
860
08/11/2018
Compensation
Common
12/01/2018
Restricted Stock Vesting
Issuer
N
1636
12/01/2018
Compensation
Common
11/12/2019
Restricted Stock Vesting
Issuer
N
871
11/12/2019
Compensation
Common
12/01/2019
Restricted Stock Vesting
Issuer
N
1170
12/01/2019
Compensation
Common
11/11/2020
Restricted Stock Vesting
Issuer
N
1195
11/11/2020
Compensation
Common
11/12/2020
Restricted Stock Vesting
Issuer
N
1131
11/12/2020
Compensation
Common
12/01/2020
Restricted Stock Vesting
Issuer
N
7269
12/01/2020
Compensation
Common
11/09/2021
Restricted Stock Vesting
Issuer
N
1116
11/09/2021
Compensation
Common
11/11/2021
Restricted Stock Vesting
Issuer
N
1195
11/11/2021
Compensation
Common
11/12/2021
Restricted Stock Vesting
Issuer
N
10008
11/12/2021
Compensation
Common
11/05/2018
Restricted Stock Vesting
Issuer
N
583
11/05/2018
Compensation
Y
05/09/2023
/s/ Lisa Gerard, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Kevin Thornal