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          <com:city>WALTHAM</com:city>
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          <com:zipCode>02451</com:zipCode>
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        <issuerContactPhone>(781)895-0600</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Coen Stacy Ann</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
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          <name>Merrill Lynch</name>
          <address>
            <com:street1>225 Liberty St</com:street1>
            <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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        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
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        <acquiredDate>08/02/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Exercise of employee stock options</natureOfAcquisitionTransaction>
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text: 144
  0001814150
  XXXXXXXX
  LIVE
  0000855654
  ImmunoGen, Inc.
  000-17999
  830 WINTER ST
  WALTHAM
  MA
  02451
  (781)895-0600
  Coen Stacy Ann
  Officer
  Common Stock
  Merrill Lynch
  225 Liberty St
  Floor 37
  New York
  NY
  10281
  4255
  77109.02
  248943426
  08/02/2023
  NASDAQ
  Common Stock
  08/02/2023
  Exercise of employee stock options
  ImmunoGen, Inc.
  N
  4255
  08/03/2023
  Broker assisted exercise of employee stock options
  Y
  08/02/2023
  Stacy Coen