<?xml version="1.0" encoding="UTF-8"?><ns2:edgarSubmission xmlns:com="http://www.sec.gov/edgar/common" xmlns:ns2="http://www.sec.gov/edgar/ownership">
    <ns2:headerData>
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        <ns2:filerInfo>
            <ns2:filer>
                <ns2:filerCredentials>
                    <ns2:cik>0001239501</ns2:cik>
                    <ns2:ccc>XXXXXXXX</ns2:ccc>
                </ns2:filerCredentials>
            </ns2:filer>
            <ns2:liveTestFlag>LIVE</ns2:liveTestFlag>



        </ns2:filerInfo>
    </ns2:headerData>
    <ns2:formData>
        <ns2:issuerInfo>
            <ns2:issuerCik>0001447362</ns2:issuerCik>
            <ns2:issuerName>Castle Biosciences, Inc.</ns2:issuerName>
            <ns2:secFileNumber>001-38984</ns2:secFileNumber>
            <ns2:issuerAddress>
                <com:street1>820 S FRIENDSWOOD DR</com:street1>
                <com:street2>SUITE 201</com:street2>
                <com:city>FRIENDSWOOD</com:city>
                <com:stateOrCountry>TX</com:stateOrCountry>
                <com:zipCode>77546</com:zipCode>
            </ns2:issuerAddress>
            <ns2:issuerContactPhone>1-602-535-1997</ns2:issuerContactPhone>
            <ns2:nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Derek Maetzold</ns2:nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <ns2:relationshipsToIssuer>
                <ns2:relationshipToIssuer>Officer</ns2:relationshipToIssuer>
            </ns2:relationshipsToIssuer>
        </ns2:issuerInfo>
        <ns2:securitiesInformation>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:brokerOrMarketmakerDetails>
                <ns2:name>Goldman Sachs &amp; Co. LLC</ns2:name>
                <ns2:address>
                    <com:street1>200 West Street</com:street1>
                    <com:city>New York</com:city>
                    <com:stateOrCountry>NY</com:stateOrCountry>
                    <com:zipCode>10282</com:zipCode>
                </ns2:address>
            </ns2:brokerOrMarketmakerDetails>
            <ns2:noOfUnitsSold>84622</ns2:noOfUnitsSold>
            <ns2:aggregateMarketValue>1588354.94</ns2:aggregateMarketValue>
            <ns2:noOfUnitsOutstanding>26691286</ns2:noOfUnitsOutstanding>
            <ns2:approxSaleDate>08/03/2023</ns2:approxSaleDate>
            <ns2:securitiesExchangeName>NASD</ns2:securitiesExchangeName>
        </ns2:securitiesInformation>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>12/18/2020</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>15302</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/29/2007</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>12/18/2020</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>15301</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/29/2007</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>01/10/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>5417</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/29/2007</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>01/10/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>5415</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/29/2007</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>01/10/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>5415</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/29/2007</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>01/10/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>5415</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/29/2007</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>10/29/2007</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired from issuer in private transaction</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>17885</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/29/2007</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>12/09/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired as compensation -- Restricted Stock Units</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>14472</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>12/09/2022</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>N</ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/04/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>697</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>15038.83</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/04/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>697</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>15038.83</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/04/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>2792</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>60241.65</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold Descendants 2020 Trust dtd 12/4/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/04/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>1396</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>30120.82</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/04/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>697</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>15038.83</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/04/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>1396</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>30120.82</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/04/2023</ns2:saleDate>
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            <ns2:grossProceeds>15038.83</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/15/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>384</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>8980.51</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold Descendants 2020 Trust dtd 12/4/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/15/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>769</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>17984.41</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/15/2023</ns2:saleDate>
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            <ns2:grossProceeds>17984.41</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
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            <ns2:saleDate>05/15/2023</ns2:saleDate>
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        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
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            <ns2:saleDate>05/15/2023</ns2:saleDate>
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        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold</ns2:name>
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                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/15/2023</ns2:saleDate>
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            <ns2:grossProceeds>35968.84</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
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        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold Descendants 2020 Trust dtd 12/4/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/16/2023</ns2:saleDate>
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            <ns2:grossProceeds>14270.52</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/16/2023</ns2:saleDate>
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        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk</ns2:name>
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                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/16/2023</ns2:saleDate>
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        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/16/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>313</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>7123.88</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/16/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>1254</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>28541.05</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/16/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>313</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>7123.88</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>05/16/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>313</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>7123.88</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>07/07/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>2091</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>41785.79</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>07/07/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>2091</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>41785.79</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>07/07/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>2091</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>41785.79</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>07/07/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>2091</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>41785.79</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold Descendants 2020 Trust dtd 12/4/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>07/07/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>4188</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>83691.47</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>07/07/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>8376</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>167382.96</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020</ns2:name>
                <ns2:address>
                    <com:street1>820 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 201</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>07/07/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>4188</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>83691.47</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:remarks>Total number of shares to be sold includes:
32,357  shares by Derek Maetzold,
15,301 shares by DM 2020 Irrev Tr,
15,302 shares by Maetzold Descendants 2020 Tr,
5,415 shares by Hannah Maetzold Irrev. Trust,
5,415 shares by Peter Maetzold Irrev. Trust,
5,417 shares by Emily Maetzold Irrev. Trust,
5,415 shares by John Maetzold Irrev. Trust.
The sales of shares set forth herein are made in connection with a selling plan dated 3/16/2023 that is intended to comply with Rule 10b5-1(c).</ns2:remarks>
        <ns2:noticeSignature>
            <ns2:noticeDate>08/03/2023</ns2:noticeDate>
            <ns2:planAdoptionDates>
                <ns2:planAdoptionDate>03/16/2023</ns2:planAdoptionDate>
            </ns2:planAdoptionDates>
            <ns2:signature>Goldman Sachs &amp; Co. LLC on behalf of Derek Maetzold</ns2:signature>
        </ns2:noticeSignature>
    </ns2:formData>
</ns2:edgarSubmission>
[{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 33123}]
144
0001239501
XXXXXXXX
LIVE
0001447362
Castle Biosciences, Inc.
001-38984
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
1-602-535-1997
Derek Maetzold
Officer
Common
Goldman Sachs & Co. LLC
200 West Street
New York
NY
10282
84622
1588354.94
26691286
08/03/2023
NASD
Common
12/18/2020
Acquired as gift
Derek Maetzold
Y
10/29/2007
15302
10/29/2007
N/A
Common
12/18/2020
Acquired as gift
Derek Maetzold
Y
10/29/2007
15301
10/29/2007
N/A
Common
01/10/2022
Acquired as gift
Derek Maetzold
Y
10/29/2007
5417
10/29/2007
N/A
Common
01/10/2022
Acquired as gift
Derek Maetzold
Y
10/29/2007
5415
10/29/2007
N/A
Common
01/10/2022
Acquired as gift
Derek Maetzold
Y
10/29/2007
5415
10/29/2007
N/A
Common
01/10/2022
Acquired as gift
Derek Maetzold
Y
10/29/2007
5415
10/29/2007
N/A
Common
10/29/2007
Acquired from issuer in private transaction
Issuer
N
17885
10/29/2007
N/A
Common
12/09/2022
Acquired as compensation -- Restricted Stock Units
Issuer
N
14472
12/09/2022
Compensation
N
The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/04/2023
697
15038.83
The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/04/2023
697
15038.83
Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/04/2023
2792
60241.65
The Maetzold Descendants 2020 Trust dtd 12/4/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/04/2023
1396
30120.82
The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/04/2023
697
15038.83
Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/04/2023
1396
30120.82
The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/04/2023
697
15038.83
The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/15/2023
384
8980.51
The Maetzold Descendants 2020 Trust dtd 12/4/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/15/2023
769
17984.41
Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/15/2023
769
17984.41
The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/15/2023
384
8980.51
The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/15/2023
384
8980.51
Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/15/2023
1538
35968.84
The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/15/2023
384
8980.51
The Maetzold Descendants 2020 Trust dtd 12/4/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/16/2023
627
14270.52
Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/16/2023
627
14270.52
The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/16/2023
313
7123.88
The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/16/2023
313
7123.88
Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/16/2023
1254
28541.05
The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/16/2023
313
7123.88
The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
05/16/2023
313
7123.88
The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
07/07/2023
2091
41785.79
The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
07/07/2023
2091
41785.79
The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
07/07/2023
2091
41785.79
The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
07/07/2023
2091
41785.79
The Maetzold Descendants 2020 Trust dtd 12/4/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
07/07/2023
4188
83691.47
Derek Maetzold
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
07/07/2023
8376
167382.96
Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020
820 S FRIENDSWOOD DR
SUITE 201
FRIENDSWOOD
TX
77546
Common
07/07/2023
4188
83691.47
Total number of shares to be sold includes:
32,357  shares by Derek Maetzold,
15,301 shares by DM 2020 Irrev Tr,
15,302 shares by Maetzold Descendants 2020 Tr,
5,415 shares by Hannah Maetzold Irrev. Trust,
5,415 shares by Peter Maetzold Irrev. Trust,
5,417 shares by Emily Maetzold Irrev. Trust,
5,415 shares by John Maetzold Irrev. Trust.
The sales of shares set forth herein are made in connection with a selling plan dated 3/16/2023 that is intended to comply with Rule 10b5-1(c).
08/03/2023
03/16/2023
Goldman Sachs & Co. LLC on behalf of Derek Maetzold