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            <filer>
                <filerCredentials>
                    <cik>0002022925</cik>
                    <ccc>XXXXXXXX</ccc>
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            <liveTestFlag>LIVE</liveTestFlag>



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    <formData>
        <issuerInfo>
            <issuerCik>0001923840</issuerCik>
            <issuerName>THIRD HARMONIC BIO, INC.</issuerName>
            <secFileNumber>001-41498</secFileNumber>
            <issuerAddress>
                <ns2:street1>1700 Montgomery Street, Suite 210</ns2:street1>
                <ns2:city>San Francisco</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>94111</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>2097272457</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>JENNIFER DITTMAN</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>1536</noOfUnitsSold>
            <aggregateMarketValue>21296.64</aggregateMarketValue>
            <noOfUnitsOutstanding>40949463</noOfUnitsOutstanding>
            <approxSaleDate>05/20/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>05/20/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1536</amountOfSecuritiesAcquired>
            <paymentDate>05/20/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for JENNIFER DITTMAN</name>
                <address>
                    <ns2:street1>1700 Montgomery Street, Suite 210</ns2:street1>
                    <ns2:city>San Francisco</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94111</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>05/16/2024</saleDate>
            <amountOfSecuritiesSold>23578</amountOfSecuritiesSold>
            <grossProceeds>331064.50</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>05/20/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>03/27/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Jennifer Dittman</signature>
        </noticeSignature>
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144
0002022925
XXXXXXXX
LIVE
0001923840
THIRD HARMONIC BIO, INC.
001-41498
1700 Montgomery Street, Suite 210
San Francisco
CA
94111
2097272457
JENNIFER DITTMAN
Officer
COMMON
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
1536
21296.64
40949463
05/20/2024
NASDAQ
Common
05/20/2024
Exercise of Stock Options
Issuer
N
1536
05/20/2024
Cash
N
10b5-1 Sales for JENNIFER DITTMAN
1700 Montgomery Street, Suite 210
San Francisco
CA
94111
COMMON
05/16/2024
23578
331064.50
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.
05/20/2024
03/27/2024
/s/ Jennifer Dittman