<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:ns2="http://www.sec.gov/edgar/common">
    <headerData>
        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001789632</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001786205</issuerCik>
            <issuerName>ARCELLX INC</issuerName>
            <secFileNumber>001-41259</secFileNumber>
            <issuerAddress>
                <ns2:street1>800 Bridge Parkway</ns2:street1>
                <ns2:city>Redwood City</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>94065</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>2403270603</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>CHRISTOPHER HEERY</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>34579</noOfUnitsSold>
            <aggregateMarketValue>1867266.00</aggregateMarketValue>
            <noOfUnitsOutstanding>53502572</noOfUnitsOutstanding>
            <approxSaleDate>06/12/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>06/12/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>34579</amountOfSecuritiesAcquired>
            <paymentDate>06/12/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for CHRISTOPHER R HEERY</name>
                <address>
                    <ns2:street1>800 Bridge Parkway</ns2:street1>
                    <ns2:city>Redwood City</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94065</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>05/01/2024</saleDate>
            <amountOfSecuritiesSold>18168</amountOfSecuritiesSold>
            <grossProceeds>932557.09</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for CHRISTOPHER R HEERY</name>
                <address>
                    <ns2:street1>800 Bridge Parkway</ns2:street1>
                    <ns2:city>Redwood City</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94065</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>03/26/2024</saleDate>
            <amountOfSecuritiesSold>5450</amountOfSecuritiesSold>
            <grossProceeds>376647.87</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for CHRISTOPHER R HEERY</name>
                <address>
                    <ns2:street1>800 Bridge Parkway</ns2:street1>
                    <ns2:city>Redwood City</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94065</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>03/22/2024</saleDate>
            <amountOfSecuritiesSold>41365</amountOfSecuritiesSold>
            <grossProceeds>2903066.02</grossProceeds>
        </securitiesSoldInPast3Months>
        <remarks>The securities to be sold were and will be received upon the exercise of stock options over the next three months.&#13;
The date of acquisition and payment was and will be the date of exercise/sale.&#13;
</remarks>
        <noticeSignature>
            <noticeDate>06/12/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>12/22/2023</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Christopher Heery</signature>
        </noticeSignature>
    </formData>
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144
0001789632
XXXXXXXX
LIVE
0001786205
ARCELLX INC
001-41259
800 Bridge Parkway
Redwood City
CA
94065
2403270603
CHRISTOPHER HEERY
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
34579
1867266.00
53502572
06/12/2024
NASDAQ
Common
06/12/2024
Exercise of Stock Options
Issuer
N
34579
06/12/2024
Cash
N
10b5-1 Sales for CHRISTOPHER R HEERY
800 Bridge Parkway
Redwood City
CA
94065
Common
05/01/2024
18168
932557.09
10b5-1 Sales for CHRISTOPHER R HEERY
800 Bridge Parkway
Redwood City
CA
94065
Common
03/26/2024
5450
376647.87
10b5-1 Sales for CHRISTOPHER R HEERY
800 Bridge Parkway
Redwood City
CA
94065
Common
03/22/2024
41365
2903066.02
The securities to be sold were and will be received upon the exercise of stock options over the next three months.
The date of acquisition and payment was and will be the date of exercise/sale.
06/12/2024
12/22/2023
/s/ Christopher Heery