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        <com:stateOrCountry>MA</com:stateOrCountry>
        <com:zipCode>01862</com:zipCode>
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      <issuerContactPhone>978 671-8001</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Montagut Etienne</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
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          <com:street2>South Building</com:street2>
          <com:city>Bedford</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>01730</com:zipCode>
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          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>01730</com:zipCode>
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      <securitiesClassTitle>Common</securitiesClassTitle>
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      <grossProceeds>1178656.64</grossProceeds>
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    <noticeSignature>
      <noticeDate>04/03/2023</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>02/24/2023</planAdoptionDate>
      </planAdoptionDates>
      <signature>/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for  Etienne Montagut</signature>
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144
0001861389
XXXXXXXX
LIVE
0001521036
Lantheus Holdings, Inc.
001-36569
331 TREBLE COVE ROAD
NORTH BILLERICA
MA
01862
978 671-8001
Montagut Etienne
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
900 Salem Street
RI
02917
3684
302419.56
67540065
04/03/2023
NASDAQ
Common
03/04/2023
Restricted Stock Vesting
Issuer
N
3684
03/04/2023
Compensation
N
ETIENNE MONTAGUT
201 Burlington Road
South Building
Bedford
MA
01730
Common
03/06/2023
14179
1028839.58
ETIENNE MONTAGUT
201 Burlington Road
South Building
Bedford
MA
01730
Common
03/07/2023
3531
254776.83
ETIENNE MONTAGUT
201 Burlington Road
South Building
Bedford
MA
01730
Common
03/27/2023
14528
1178656.64
04/03/2023
02/24/2023
/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for  Etienne Montagut