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    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001787397</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
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    <issuerInfo>
      <issuerCik>0001326732</issuerCik>
      <issuerName>Xencor Inc</issuerName>
      <secFileNumber>001-36182</secFileNumber>
      <issuerAddress>
        <com:street1>111 WEST LEMON AVE</com:street1>
        <com:city>MONROVIA</com:city>
        <com:stateOrCountry>CA</com:stateOrCountry>
        <com:zipCode>91016</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>626-305-5900</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Eckert Celia</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>711</noOfUnitsSold>
      <aggregateMarketValue>21244.18</aggregateMarketValue>
      <noOfUnitsOutstanding>60030076</noOfUnitsOutstanding>
      <approxSaleDate>03/09/2023</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>03/08/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>711</amountOfSecuritiesAcquired>
      <paymentDate>03/08/2023</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Celia Eckert</name>
        <address>
          <com:street1>111 West Lemon Avenue</com:street1>
          <com:city>Monrovia</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>91016</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>03/03/2023</saleDate>
      <amountOfSecuritiesSold>427</amountOfSecuritiesSold>
      <grossProceeds>13466.77</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Celia Eckert</name>
        <address>
          <com:street1>111 West Lemon Avenue</com:street1>
          <com:city>Monrovia</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>91016</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>03/06/2023</saleDate>
      <amountOfSecuritiesSold>2462</amountOfSecuritiesSold>
      <grossProceeds>77345.95</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>03/09/2023</noticeDate>
      <signature>/s/ Jennifer Ruchti, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Celia Eckert</signature>
    </noticeSignature>
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144
0001787397
XXXXXXXX
LIVE
0001326732
Xencor Inc
001-36182
111 WEST LEMON AVE
MONROVIA
CA
91016
626-305-5900
Eckert Celia
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
711
21244.18
60030076
03/09/2023
NASDAQ
Common
03/08/2023
Restricted Stock Vesting
Issuer
N
711
03/08/2023
Compensation
N
Celia Eckert
111 West Lemon Avenue
Monrovia
CA
91016
Common
03/03/2023
427
13466.77
Celia Eckert
111 West Lemon Avenue
Monrovia
CA
91016
Common
03/06/2023
2462
77345.95
03/09/2023
/s/ Jennifer Ruchti, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Celia Eckert