<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
  <!-- Generated by Workiva -->
  <headerData>
    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001509282</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0001350653</issuerCik>
      <issuerName>Alphatec Holdings</issuerName>
      <secFileNumber>000-52024</secFileNumber>
      <issuerAddress>
        <com:street1>1950 Camino Vida Roble</com:street1>
        <com:city>Carlsbad</com:city>
        <com:stateOrCountry>CA</com:stateOrCountry>
        <com:zipCode>92008</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>7604319286</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Craig Hunsaker</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Merrill Lynch</name>
        <address>
          <com:street1>701 B Street</com:street1>
          <com:street2>suite 2400</com:street2>
          <com:city>San Diego</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92101</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>95000</noOfUnitsSold>
      <aggregateMarketValue>1159000</aggregateMarketValue>
      <noOfUnitsOutstanding>151356620</noOfUnitsOutstanding>
      <approxSaleDate>03/06/2026</approxSaleDate>
      <securitiesExchangeName>nasdaq</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>common</securitiesClassTitle>
      <acquiredDate>03/05/2026</acquiredDate>
      <natureOfAcquisitionTransaction>RSU</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>craig hunsaker</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>66041</amountOfSecuritiesAcquired>
      <paymentDate>03/06/2026</paymentDate>
      <natureOfPayment>sold to cover</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>common</securitiesClassTitle>
      <acquiredDate>03/05/2026</acquiredDate>
      <natureOfAcquisitionTransaction>PSU</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>craig hunsaker</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>162665</amountOfSecuritiesAcquired>
      <paymentDate>03/06/2026</paymentDate>
      <natureOfPayment>sold to cover</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>craig hunsaker</name>
        <address>
          <com:street1>1950 Camino Vida Roble</com:street1>
          <com:city>Carlsbad</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92008</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>common</securitiesClassTitle>
      <saleDate>12/10/2025</saleDate>
      <amountOfSecuritiesSold>32584</amountOfSecuritiesSold>
      <grossProceeds>676889</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>03/06/2026</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>06/04/2025</planAdoptionDate>
      </planAdoptionDates>
      <signature>Jackie Mulford</signature>
    </noticeSignature>
  </formData>
</edgarSubmission>
