<?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>505 S FRIENDSWOOD DR</com:street1>
                <com:street2>SUITE 401</com:street2>
                <com:city>FRIENDSWOOD</com:city>
                <com:stateOrCountry>TX</com:stateOrCountry>
                <com:zipCode>77546</com:zipCode>
            </ns2:issuerAddress>
            <ns2:issuerContactPhone>1-866-788-9007</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>76096</ns2:noOfUnitsSold>
            <ns2:aggregateMarketValue>1526485.76</ns2:aggregateMarketValue>
            <ns2:noOfUnitsOutstanding>26910548</ns2:noOfUnitsOutstanding>
            <ns2:approxSaleDate>11/20/2023</ns2:approxSaleDate>
            <ns2:securitiesExchangeName>NASD</ns2:securitiesExchangeName>
        </ns2:securitiesInformation>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>10/29/2007</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>11479</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 as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>11479</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 as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>4183</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 as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>4182</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 as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>4182</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 as gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Derek Maetzold</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>10/29/2007</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>4182</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>02/02/2019</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired in a private transaction</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>8098</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>02/12/2019</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>12/10/2021</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired in a merger</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>3252</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>12/10/2021</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>11/16/2021</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Option Exercise</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>15409</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>11/16/2021</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>05/12/2020</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Acquired in private transaction</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>9650</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>05/12/2020</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>N</ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Maetzold Descendants 2020 Trust dtd 12/4/2020</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/31/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>1289</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>25854.76</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/31/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>473</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>9487.43</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/31/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>473</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>9487.43</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/31/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>4084</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>81916.87</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/31/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>1289</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>25854.76</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/31/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>473</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>9487.43</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/31/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>474</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>9507.49</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>09/01/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>226</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>4531.75</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>09/01/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>83</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>1664.32</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>09/01/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>83</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>1664.32</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>09/01/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>718</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>14397.34</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>09/01/2023</ns2:saleDate>
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            <ns2:grossProceeds>4531.75</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>09/01/2023</ns2:saleDate>
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            <ns2:grossProceeds>1664.32</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>09/01/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>81</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>1624.21</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/30/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>512</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>10256.69</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
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            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>08/30/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>189</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>3786.16</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/30/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>189</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>3786.16</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>Derek Maetzold</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/30/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>1622</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>32492.88</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/30/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>512</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>10256.69</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/30/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>189</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>3786.16</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>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</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>08/30/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>187</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>3746.1</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:remarks>Total number of shares to be sold includes: 36,405 shares by Derek Maetzold, 11,479 shares by DM 2020 Irrev Tr, 11,479 shares by Maetzold Descendants 2020 Tr, 4,182 shares by Hannah Maetzold Irrev. Trust, 4,182 shares by Peter Maetzold Irrev. Trust, 4,183  shares by Emily Maetzold Irrev. Trust, 4,182 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>11/20/2023</ns2:noticeDate>
            <ns2:planAdoptionDates>
                <ns2:planAdoptionDate>08/03/2023</ns2:planAdoptionDate>
            </ns2:planAdoptionDates>
            <ns2:signature>Goldman Sachs &amp; Co. LLC on behalf of Goldman Sachs &amp; Co. LLC on behalf of Derek Maetzold</ns2:signature>
        </ns2:noticeSignature>
    </ns2:formData>
</ns2:edgarSubmission>
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144
0001239501
XXXXXXXX
LIVE
0001447362
Castle Biosciences, Inc.
001-38984
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
1-866-788-9007
Derek Maetzold
Officer
Common
Goldman Sachs & Co. LLC
200 West Street
New York
NY
10282
76096
1526485.76
26910548
11/20/2023
NASD
Common
10/29/2007
Acquired as gift
Derek Maetzold
Y
10/29/2007
11479
10/29/2007
N/A
Common
10/29/2007
Acquired as gift
Derek Maetzold
Y
10/29/2007
11479
10/29/2007
N/A
Common
10/29/2007
Acquired as gift
Derek Maetzold
Y
10/29/2007
4183
10/29/2007
N/A
Common
10/29/2007
Acquired as gift
Derek Maetzold
Y
10/29/2007
4182
10/29/2007
N/A
Common
10/29/2007
Acquired as gift
Derek Maetzold
Y
10/29/2007
4182
10/29/2007
N/A
Common
10/29/2007
Acquired as gift
Derek Maetzold
Y
10/29/2007
4182
10/29/2007
N/A
Common
02/02/2019
Acquired in a private transaction
Issuer
N
8098
02/12/2019
N/A
Common
12/10/2021
Acquired in a merger
Issuer
N
3252
12/10/2021
N/A
Common
11/16/2021
Option Exercise
Issuer
N
15409
11/16/2021
N/A
Common
05/12/2020
Acquired in private transaction
Issuer
N
9650
05/12/2020
N/A
N
The Maetzold Descendants 2020 Trust dtd 12/4/2020
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/31/2023
1289
25854.76
The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/31/2023
473
9487.43
The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/31/2023
473
9487.43
Derek Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/31/2023
4084
81916.87
Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/31/2023
1289
25854.76
The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/31/2023
473
9487.43
The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/31/2023
474
9507.49
The Maetzold Descendants 2020 Trust dtd 12/4/2020
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
09/01/2023
226
4531.75
The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
09/01/2023
83
1664.32
The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
09/01/2023
83
1664.32
Derek Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
09/01/2023
718
14397.34
Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
09/01/2023
226
4531.75
The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
09/01/2023
83
1664.32
The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
09/01/2023
81
1624.21
The Maetzold Descendants 2020 Trust dtd 12/4/2020
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/30/2023
512
10256.69
The Maetzold 2018 Remainder Trust f/b/o John Derek Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/30/2023
189
3786.16
The Maetzold 2018 Remainder Trust f/b/o Peter Douglas Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/30/2023
189
3786.16
Derek Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/30/2023
1622
32492.88
Derek Maetzold 2020 Irrevocable Trust dtd 12/04/2020
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/30/2023
512
10256.69
The Maetzold 2018 Remainder Trust f/b/o Hannah Elizabeth Maetzold
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/30/2023
189
3786.16
The Maetzold 2018 Remainder Trust f/b/o Emily Carol Kirk
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
08/30/2023
187
3746.1
Total number of shares to be sold includes: 36,405 shares by Derek Maetzold, 11,479 shares by DM 2020 Irrev Tr, 11,479 shares by Maetzold Descendants 2020 Tr, 4,182 shares by Hannah Maetzold Irrev. Trust, 4,182 shares by Peter Maetzold Irrev. Trust, 4,183  shares by Emily Maetzold Irrev. Trust, 4,182 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).
11/20/2023
08/03/2023
Goldman Sachs & Co. LLC on behalf of Goldman Sachs & Co. LLC on behalf of Derek Maetzold