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        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>IDEXX Laboratories Inc</name>
        <lei>OGMTXK0LUU1HKV2P0J84</lei>
        <title>IDEXX Laboratories Inc</title>
        <cusip>45168D104</cusip>
        <identifiers>
          <isin value="US45168D1046"/>
        </identifiers>
        <balance>47440.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>24974313.60000000</valUSD>
        <pctVal>1.336899129933</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Intuit Inc</name>
        <lei>VI90HBPH7XSFMB9E4M29</lei>
        <title>Intuit Inc</title>
        <cusip>461202103</cusip>
        <identifiers>
          <isin value="US4612021034"/>
        </identifiers>
        <balance>52000.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>13572000.00000000</valUSD>
        <pctVal>0.726522269323</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Keysight Technologies Inc</name>
        <lei>549300GLKVIO8YRCYN02</lei>
        <title>Keysight Technologies Inc</title>
        <cusip>49338L103</cusip>
        <identifiers>
          <isin value="US49338L1035"/>
        </identifiers>
        <balance>11640.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4074814.80000000</valUSD>
        <pctVal>0.218128772146</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Marriott International Inc/MD</name>
        <lei>225YDZ14ZO8E1TXUSU86</lei>
        <title>Marriott International Inc/MD</title>
        <cusip>571903202</cusip>
        <identifiers>
          <isin value="US5719032022"/>
        </identifiers>
        <balance>49150.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>18214498.50000000</valUSD>
        <pctVal>0.975039698261</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Martin Marietta Materials Inc</name>
        <lei>5299005MZ4WZECVATV08</lei>
        <title>Martin Marietta Materials Inc</title>
        <cusip>573284106</cusip>
        <identifiers>
          <isin value="US5732841060"/>
        </identifiers>
        <balance>28070.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>16187969.00000000</valUSD>
        <pctVal>0.866557616682</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Mastercard Inc</name>
        <lei>AR5L2ODV9HN37376R084</lei>
        <title>Mastercard Inc</title>
        <cusip>57636Q104</cusip>
        <identifiers>
          <isin value="US57636Q1040"/>
        </identifiers>
        <balance>140970.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>72402192.00000000</valUSD>
        <pctVal>3.875759271721</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Microsoft Corp</name>
        <lei>INR2EJN1ERAN0W5ZP974</lei>
        <title>Microsoft Corp</title>
        <cusip>594918104</cusip>
        <identifiers>
          <isin value="US5949181045"/>
        </identifiers>
        <balance>348560.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>130019851.20000000</valUSD>
        <pctVal>6.960088222138</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Monster Beverage Corp</name>
        <lei>52990090AP0E7HCB6F33</lei>
        <title>Monster Beverage Corp</title>
        <cusip>61174X109</cusip>
        <identifiers>
          <isin value="US61174X1090"/>
        </identifiers>
        <balance>413780.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>39772533.60000000</valUSD>
        <pctVal>2.129062140273</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Mueller Industries Inc</name>
        <lei>5493005IZFE4VJLLYG84</lei>
        <title>Mueller Industries Inc</title>
        <cusip>624756102</cusip>
        <identifiers>
          <isin value="US6247561029"/>
        </identifiers>
        <balance>79290.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>9747119.70000000</valUSD>
        <pctVal>0.521772732376</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>NVIDIA Corp</name>
        <lei>549300S4KLFTLO7GSQ80</lei>
        <title>NVIDIA Corp</title>
        <cusip>67066G104</cusip>
        <identifiers>
          <isin value="US67066G1040"/>
        </identifiers>
        <balance>1304410.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>260999396.90000000</valUSD>
        <pctVal>13.97154981784</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>O'Reilly Automotive Inc</name>
        <lei>549300K2RLMQL149Q332</lei>
        <title>O'Reilly Automotive Inc</title>
        <cusip>67103H107</cusip>
        <identifiers>
          <isin value="US67103H1077"/>
        </identifiers>
        <balance>300240.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>27649101.60000000</valUSD>
        <pctVal>1.480083115176</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>ServiceNow Inc</name>
        <lei>549300HJTQM36M0E1G39</lei>
        <title>ServiceNow Inc</title>
        <cusip>81762P102</cusip>
        <identifiers>
          <isin value="US81762P1021"/>
        </identifiers>
        <balance>246720.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>24494361.60000000</valUSD>
        <pctVal>1.311206835783</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Snowflake Inc</name>
        <lei>254900CJNSY1K7T53Z16</lei>
        <title>Snowflake Inc</title>
        <cusip>833445109</cusip>
        <identifiers>
          <isin value="US8334451098"/>
        </identifiers>
        <balance>134040.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>34113180.00000000</valUSD>
        <pctVal>1.826111475642</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Space Exploration Technologies Corp</name>
        <lei>549300B9WLO96RQCXP87</lei>
        <title>Space Exploration Technologies Corp</title>
        <cusip>84615Q103</cusip>
        <identifiers>
          <isin value="US84615Q1031"/>
        </identifiers>
        <balance>51339.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>8771781.54000000</valUSD>
        <pctVal>0.469561938582</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Fixed Income Clearing Corp.</name>
        <lei>549300H47WTHXPU08X20</lei>
        <title>FIXED INC CLEARING CORP.REPO</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="85748R009"/>
        </identifiers>
        <balance>13145292.51000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>13145292.51000000</valUSD>
        <pctVal>0.703680205222</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>RA</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <repurchaseAgrmt>
          <transCat>Repurchase</transCat>
          <clearedCentCparty centralCounterparty="Fixed Income Clearing Corp." isCleared="Y"/>
          <isTriParty>N</isTriParty>
          <repurchaseRt>1.15000000</repurchaseRt>
          <maturityDt>2026-07-01</maturityDt>
          <repurchaseCollaterals>
            <repurchaseCollateral>
              <principalAmt>13377300.00000000</principalAmt>
              <principalCd>USD</principalCd>
              <collateralVal>13408198.36000000</collateralVal>
              <collateralCd>USD</collateralCd>
              <invstCat>UST</invstCat>
            </repurchaseCollateral>
          </repurchaseCollaterals>
        </repurchaseAgrmt>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Texas Instruments Inc</name>
        <lei>WDJNR2L6D8RWOEB8T652</lei>
        <title>Texas Instruments Inc</title>
        <cusip>882508104</cusip>
        <identifiers>
          <isin value="US8825081040"/>
        </identifiers>
        <balance>51440.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>15332720.80000000</valUSD>
        <pctVal>0.820775354443</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>TransUnion</name>
        <lei>549300ZS772LUNUMRB03</lei>
        <title>TransUnion</title>
        <cusip>89400J107</cusip>
        <identifiers>
          <isin value="US89400J1079"/>
        </identifiers>
        <balance>268440.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>19365261.60000000</valUSD>
        <pctVal>1.036641158537</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>UnitedHealth Group Inc</name>
        <lei>549300GHBMY8T5GXDE41</lei>
        <title>UnitedHealth Group Inc</title>
        <cusip>91324P102</cusip>
        <identifiers>
          <isin value="US91324P1021"/>
        </identifiers>
        <balance>90175.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>37479435.25000000</valUSD>
        <pctVal>2.006310370673</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Verisk Analytics Inc</name>
        <lei>549300I1YSWNIRKBWP67</lei>
        <title>Verisk Analytics Inc</title>
        <cusip>92345Y106</cusip>
        <identifiers>
          <isin value="US92345Y1064"/>
        </identifiers>
        <balance>70390.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12637116.70000000</valUSD>
        <pctVal>0.676477063261</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>West Pharmaceutical Services Inc</name>
        <lei>5493007NKRGM1RJQ1P16</lei>
        <title>West Pharmaceutical Services Inc</title>
        <cusip>955306105</cusip>
        <identifiers>
          <isin value="US9553061055"/>
        </identifiers>
        <balance>64830.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>23273970.00000000</valUSD>
        <pctVal>1.245878094647</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Linde PLC</name>
        <lei>5299003QR1WT0EF88V51</lei>
        <title>Linde PLC</title>
        <cusip>000000000</cusip>
        <identifiers>
          <isin value="IE000S9YS762"/>
        </identifiers>
        <balance>58580.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>30399505.20000000</valUSD>
        <pctVal>1.627314876525</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>IE</invCountry>
        
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Seagate Technology Holdings PLC</name>
        <lei>635400RUXIFEZSRU8X70</lei>
        <title>Seagate Technology Holdings PLC</title>
        <cusip>000000000</cusip>
        <identifiers>
          <isin value="IE00BKVD2N49"/>
        </identifiers>
        <balance>29680.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>28641200.00000000</valUSD>
        <pctVal>1.533191100805</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>IE</invCountry>
        
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
    </invstOrSecs>
    <explntrNotes>
      <explntrNote note="Monthly returns presented in Item B.5(a) have been calculated without deducting any applicable sales loads or redemption fees." noteItem="B.5.a"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2026-07-15</ncom:dateSigned>
      <ncom:nameOfApplicant>WILLIAM BLAIR FUNDS</ncom:nameOfApplicant>
      <ncom:signature>John Raczek</ncom:signature>
      <ncom:signerName>John Raczek</ncom:signerName>
      <ncom:title>Principal Financial Officer</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
