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      <secFileNumber>001-40777</secFileNumber>
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        <com:street1>NOVA NORTH</com:street1>
        <com:street2>7 FLOOR, 11 BRESSENDEN PLACE</com:street2>
        <com:city>LONDON</com:city>
        <com:stateOrCountry>X0</com:stateOrCountry>
        <com:zipCode>SW1E 5BY</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>44 203 91 70155</issuerContactPhone>
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      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
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      <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>
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      <aggregateMarketValue>3183.00</aggregateMarketValue>
      <noOfUnitsOutstanding>121926166</noOfUnitsOutstanding>
      <approxSaleDate>05/09/2023</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
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      <natureOfAcquisitionTransaction>Options Granted 05/01/2020</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>3000</amountOfSecuritiesAcquired>
      <paymentDate>05/09/2023</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
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    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
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        <name>Patrick Willcocks</name>
        <address>
          <com:street1>Nova North</com:street1>
          <com:street2>7 Floor, 11 Bressenden Place</com:street2>
          <com:city>London</com:city>
          <com:stateOrCountry>X0</com:stateOrCountry>
          <com:zipCode>SW1E 5BY</com:zipCode>
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      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>04/03/2023</saleDate>
      <amountOfSecuritiesSold>2408</amountOfSecuritiesSold>
      <grossProceeds>3061.30</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>05/09/2023</noticeDate>
      <signature>/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Patrick Willcocks</signature>
    </noticeSignature>
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144
0001967211
XXXXXXXX
LIVE
0001859690
Arqit Quantum Inc.
001-40777
NOVA NORTH
7 FLOOR, 11 BRESSENDEN PLACE
LONDON
X0
SW1E 5BY
44 203 91 70155
Willcocks Patrick
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
3000
3183.00
121926166
05/09/2023
NASDAQ
Common
05/09/2023
Options Granted 05/01/2020
Issuer
N
3000
05/09/2023
Cash
N
Patrick Willcocks
Nova North
7 Floor, 11 Bressenden Place
London
X0
SW1E 5BY
Common
04/03/2023
2408
3061.30
05/09/2023
/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Patrick Willcocks