content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
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        <filer>
          <filerCredentials>
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            <ccc>XXXXXXXX</ccc>
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        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
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        <issuerCik>0001722964</issuerCik>
        <issuerName>Y-mAbs Therapeutics, Inc.</issuerName>
        <secFileNumber>001-38650</secFileNumber>
        <issuerAddress>
          <com:street1>230 Park Avenue</com:street1>
          <com:street2>Suite3350</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10169</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>6468858505</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Gad Enterprises LLC  (Thomas Gad)</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
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      <securitiesInformation>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>J.P. Morgan Securities LLC</name>
          <address>
            <com:street1>390 Madison Avenue</com:street1>
            <com:street2>6th Floor</com:street2>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10017</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>150000</noOfUnitsSold>
        <aggregateMarketValue>1015500</aggregateMarketValue>
        <noOfUnitsOutstanding>43621618</noOfUnitsOutstanding>
        <approxSaleDate>12/13/2023</approxSaleDate>
        <securitiesExchangeName>Nasdaq</securitiesExchangeName>
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      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>08/15/2015</acquiredDate>
        <natureOfAcquisitionTransaction>Private Investment</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>150000</amountOfSecuritiesAcquired>
        <paymentDate>08/15/2015</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
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          <name>Gad Enterprises (Thomas Gad)</name>
          <address>
            <com:street1>230 Park Avenue</com:street1>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10169</com:zipCode>
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        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>11/20/2023</saleDate>
        <amountOfSecuritiesSold>75000</amountOfSecuritiesSold>
        <grossProceeds>392432</grossProceeds>
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          <name>Gad Enterprises (Thomas Gad)</name>
          <address>
            <com:street1>230 Park Avenue</com:street1>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10169</com:zipCode>
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        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>11/21/2023</saleDate>
        <amountOfSecuritiesSold>75000</amountOfSecuritiesSold>
        <grossProceeds>393010</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>12/13/2023</noticeDate>
        <signature>/s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Gad Enterprises LLC</signature>
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text: 144
  0001753224
  XXXXXXXX
  LIVE
  0001722964
  Y-mAbs Therapeutics, Inc.
  001-38650
  230 Park Avenue
  Suite3350
  New York
  NY
  10169
  6468858505
  Gad Enterprises LLC  (Thomas Gad)
  Officer
  Common Stock
  J.P. Morgan Securities LLC
  390 Madison Avenue
  6th Floor
  New York
  NY
  10017
  150000
  1015500
  43621618
  12/13/2023
  Nasdaq
  Common
  08/15/2015
  Private Investment
  Issuer
  N
  150000
  08/15/2015
  Cash
  N
  Gad Enterprises (Thomas Gad)
  230 Park Avenue
  New York
  NY
  10169
  Common
  11/20/2023
  75000
  392432
  Gad Enterprises (Thomas Gad)
  230 Park Avenue
  New York
  NY
  10169
  Common
  11/21/2023
  75000
  393010
  12/13/2023
  /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Gad Enterprises LLC