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            <com:street2>Floor 37</com:street2>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10281</com:zipCode>
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        <amountOfSecuritiesAcquired>97632</amountOfSecuritiesAcquired>
        <paymentDate>01/30/2025</paymentDate>
        <natureOfPayment>Broker assisted cashless exercise</natureOfPayment>
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          <name>Craig Hopkinson</name>
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            <com:street2>1 BURLINGTON ROAD</com:street2>
            <com:city>DUBLIN 4</com:city>
            <com:stateOrCountry>L2</com:stateOrCountry>
            <com:zipCode>00000</com:zipCode>
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        <securitiesClassTitle>Ordinary shares</securitiesClassTitle>
        <saleDate>11/06/2024</saleDate>
        <amountOfSecuritiesSold>10471</amountOfSecuritiesSold>
        <grossProceeds>309169.27</grossProceeds>
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            <com:stateOrCountry>L2</com:stateOrCountry>
            <com:zipCode>00000</com:zipCode>
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            <com:street2>1 BURLINGTON ROAD</com:street2>
            <com:city>DUBLIN 4</com:city>
            <com:stateOrCountry>L2</com:stateOrCountry>
            <com:zipCode>00000</com:zipCode>
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        <securitiesClassTitle>Ordinary shares</securitiesClassTitle>
        <saleDate>12/04/2024</saleDate>
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        <grossProceeds>441550.16</grossProceeds>
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            <com:zipCode>00000</com:zipCode>
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            <com:zipCode>00000</com:zipCode>
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        <securitiesClassTitle>Ordinary shares</securitiesClassTitle>
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      <noticeSignature>
        <noticeDate>01/30/2025</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>12/14/2023</planAdoptionDate>
        </planAdoptionDates>
        <signature>Craig Hopkinson</signature>
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text: 144
  0001730048
  XXXXXXXX
  LIVE
  0001520262
  Alkermes plc.
  001-35299
  CONNAUGHT HOUSE
  1 BURLINGTON ROAD
  DUBLIN 4
  L2
  00000
  00-353-1-772-8000
  Hopkinson Craig C.
  Officer
  Ordinary shares
  Merrill Lynch
  225 Liberty St
  Floor 37
  New York
  NY
  10281
  100918
  3234380.13
  161802508
  01/30/2025
  NASDAQ
  Ordinary shares
  02/08/2024
  Vesting of performance share unit award
  Alkermes plc.
  N
  3286
  02/08/2024
  Granted as part of issuer equity compensation plan
  Ordinary shares
  01/30/2025
  Exercise of employee stock options
  Alkermes plc.
  N
  97632
  01/30/2025
  Broker assisted cashless exercise
  N
  Craig Hopkinson
  CONNAUGHT HOUSE
  1 BURLINGTON ROAD
  DUBLIN 4
  L2
  00000
  Ordinary shares
  11/06/2024
  10471
  309169.27
  Craig Hopkinson
  CONNAUGHT HOUSE
  1 BURLINGTON ROAD
  DUBLIN 4
  L2
  00000
  Ordinary shares
  11/11/2024
  58996
  1774578.08
  Craig Hopkinson
  CONNAUGHT HOUSE
  1 BURLINGTON ROAD
  DUBLIN 4
  L2
  00000
  Ordinary shares
  12/04/2024
  14349
  441550.16
  Craig Hopkinson
  CONNAUGHT HOUSE
  1 BURLINGTON ROAD
  DUBLIN 4
  L2
  00000
  Ordinary shares
  12/05/2024
  9221
  290461.50
  Craig Hopkinson
  CONNAUGHT HOUSE
  1 BURLINGTON ROAD
  DUBLIN 4
  L2
  00000
  Ordinary shares
  12/09/2024
  61151
  1961403.62
  01/30/2025
  12/14/2023
  Craig Hopkinson