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  <issuerName>Mereo BioPharma Group plc</issuerName>
  <secFileNumber>001-38452</secFileNumber>
  <issuerAddress>
  <street1 xmlns="http://www.sec.gov/edgar/common">4th Floor, One Cavendish Place</street1>
  <city xmlns="http://www.sec.gov/edgar/common">London</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">X0</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">W1G 0QF</zipCode>
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  <issuerContactPhone>44-333 023 7300</issuerContactPhone>
  <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Sermon Charles</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
  <relationshipsToIssuer>
  <relationshipToIssuer>Officer</relationshipToIssuer>
  </relationshipsToIssuer>
  </issuerInfo>
  <securitiesInformation>
  <securitiesClassTitle>American Depositary Shares Representing Ordinary Shares</securitiesClassTitle>
  <brokerOrMarketmakerDetails>
  <name>Morgan Stanley &amp; Co. LLC</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">1585 Broadway</street1>
  <city xmlns="http://www.sec.gov/edgar/common">New York</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">NY</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">10036-8293</zipCode>
  </address>
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  <noOfUnitsSold>30926</noOfUnitsSold>
  <aggregateMarketValue>144115.16</aggregateMarketValue>
  <noOfUnitsOutstanding>769262609</noOfUnitsOutstanding>
  <approxSaleDate>09/12/2024</approxSaleDate>
  <securitiesExchangeName>NASDAQ</securitiesExchangeName>
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  <securitiesClassTitle>American Depositary Shares Representing Ordinary Shares</securitiesClassTitle>
  <acquiredDate>09/12/2024</acquiredDate>
  <natureOfAcquisitionTransaction>Same Day Cashless Exercise and Sale</natureOfAcquisitionTransaction>
  <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
  <isGiftTransaction>N</isGiftTransaction>
  <amountOfSecuritiesAcquired>65600</amountOfSecuritiesAcquired>
  <paymentDate>09/12/2024</paymentDate>
  <natureOfPayment>Equity Compensation</natureOfPayment>
  </securitiesToBeSold>
  <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
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  <name>Sermon Charles</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">4th Floor, One Cavendish Place</street1>
  <city xmlns="http://www.sec.gov/edgar/common">London</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">X0</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">W1G 0QF</zipCode>
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  <securitiesClassTitle>American Depositary Shares Representing Ordinary Shares</securitiesClassTitle>
  <saleDate>06/25/2024</saleDate>
  <amountOfSecuritiesSold>14202</amountOfSecuritiesSold>
  <grossProceeds>52460.77</grossProceeds>
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  <name>Sermon Charles</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">4th Floor, One Cavendish Place</street1>
  <city xmlns="http://www.sec.gov/edgar/common">London</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">X0</stateOrCountry>
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  <securitiesClassTitle>American Depositary Shares Representing Ordinary Shares</securitiesClassTitle>
  <saleDate>06/26/2024</saleDate>
  <amountOfSecuritiesSold>32187</amountOfSecuritiesSold>
  <grossProceeds>109216.93</grossProceeds>
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  <remarks>The number of shares to be sold is in the form of American Depositary Shares ("ADSs"). The number of shares outstanding is in the form of ordinary shares. Each ADS represents 5 ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer. Represents ADSs sold to cover tax obligations from vesting of Performance Based Restricted Share Units.</remarks>
  <noticeSignature>
  <noticeDate>09/12/2024</noticeDate>
  <signature>/s/ Charles Sermon</signature>
  </noticeSignature>
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text: 144
  0001687318
  XXXXXXXX
  LIVE
  0001719714
  Mereo BioPharma Group plc
  001-38452
  4th Floor, One Cavendish Place
  London
  X0
  W1G 0QF
  44-333 023 7300
  Sermon Charles
  Officer
  American Depositary Shares Representing Ordinary Shares
  Morgan Stanley & Co. LLC
  1585 Broadway
  New York
  NY
  10036-8293
  30926
  144115.16
  769262609
  09/12/2024
  NASDAQ
  American Depositary Shares Representing Ordinary Shares
  09/12/2024
  Same Day Cashless Exercise and Sale
  Issuer
  N
  65600
  09/12/2024
  Equity Compensation
  N
  Sermon Charles
  4th Floor, One Cavendish Place
  London
  X0
  W1G 0QF
  American Depositary Shares Representing Ordinary Shares
  06/25/2024
  14202
  52460.77
  Sermon Charles
  4th Floor, One Cavendish Place
  London
  X0
  W1G 0QF
  American Depositary Shares Representing Ordinary Shares
  06/26/2024
  32187
  109216.93
  The number of shares to be sold is in the form of American Depositary Shares ("ADSs"). The number of shares outstanding is in the form of ordinary shares. Each ADS represents 5 ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer. Represents ADSs sold to cover tax obligations from vesting of Performance Based Restricted Share Units.
  09/12/2024
  /s/ Charles Sermon