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    <nameOfIssuer>ADVANCED ENERGY INDUSTRIES</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>AGILYSYS INC</nameOfIssuer>
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    <nameOfIssuer>AMETEK INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>031100100</cusip>
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    <nameOfIssuer>AMPHENOL CORP CL A</nameOfIssuer>
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    <nameOfIssuer>API GROUP CORP</nameOfIssuer>
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    <nameOfIssuer>BIO TECHNE CORP</nameOfIssuer>
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    <cusip>09073M104</cusip>
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    <cusip>05605H100</cusip>
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    <cusip>127055101</cusip>
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    <nameOfIssuer>CACI INTERNATIONAL INC CL A</nameOfIssuer>
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    <cusip>127190304</cusip>
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    <nameOfIssuer>CCC INTELLIGENT SOLUTIONS HOLD</nameOfIssuer>
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    <nameOfIssuer>CHARLES RIVER LABORATORIES</nameOfIssuer>
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    <nameOfIssuer>CHARLES SCHWAB CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>808513105</cusip>
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    <nameOfIssuer>CLEAN HARBORS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>COHERENT CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>COLUMBIA BKG SYS INC.</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>197236102</cusip>
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    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>CRANE NXT CO</nameOfIssuer>
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    <nameOfIssuer>CROWN CASTLE INC.</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>DORMAN PRODS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>ENTEGRIS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>FIRST AMERICAN FINANCIAL CORP</nameOfIssuer>
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    <nameOfIssuer>FMC CORP</nameOfIssuer>
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    <nameOfIssuer>GLACIER BANCORP INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>37637Q105</cusip>
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    <nameOfIssuer>HALOZYME THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>40637H109</cusip>
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    <nameOfIssuer>HEICO CORP CL A</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>HENRY SCHEIN INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
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    <nameOfIssuer>HUNTINGTON BANCSHARES INC</nameOfIssuer>
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    <nameOfIssuer>INGREDION INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>457187102</cusip>
    <figi>BBG000BXPZB7</figi>
    <value>161654957</value>
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      <sshPrnamt>1323847</sshPrnamt>
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    <votingAuthority>
      <Sole>0</Sole>
      <Shared>1280305</Shared>
      <None>43542</None>
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    <nameOfIssuer>INTERCONTINENTAL EXCHANGE INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>45866F104</cusip>
    <figi>BBG000C1FB75</figi>
    <value>70830845</value>
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      <sshPrnamt>420411</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>420411</Shared>
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    <nameOfIssuer>KBR INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>48242W106</cusip>
    <figi>BBG000P28YZ6</figi>
    <value>116447747</value>
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      <sshPrnamt>2462418</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>2338606</Shared>
      <None>123812</None>
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    <nameOfIssuer>KEYSIGHT TECHNOLOGIES INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>49338L103</cusip>
    <figi>BBG0059FN811</figi>
    <value>36253919</value>
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      <sshPrnamt>207260</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>207260</Shared>
      <None>0</None>
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    <nameOfIssuer>LKQ CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>501889208</cusip>
    <figi>BBG000PXDL44</figi>
    <value>34310163</value>
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      <sshPrnamt>1123450</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>1123450</Shared>
      <None>0</None>
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    <nameOfIssuer>MARKEL GROUP INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>570535104</cusip>
    <figi>BBG000FC7366</figi>
    <value>13828690</value>
    <shrsOrPrnAmt>
      <sshPrnamt>7235</sshPrnamt>
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    <votingAuthority>
      <Sole>0</Sole>
      <Shared>7235</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>MASTERCARD INC CL A</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>57636Q104</cusip>
    <figi>BBG000F1ZSQ2</figi>
    <value>67923309</value>
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      <sshPrnamt>119413</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>119413</Shared>
      <None>0</None>
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    <nameOfIssuer>MCGRATH RENTCORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>580589109</cusip>
    <figi>BBG000BP02D2</figi>
    <value>44927425</value>
    <shrsOrPrnAmt>
      <sshPrnamt>383013</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>348531</Shared>
      <None>34482</None>
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    <nameOfIssuer>MERCURY SYSTEMS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>589378108</cusip>
    <figi>BBG000BX5GS3</figi>
    <value>60480670</value>
    <shrsOrPrnAmt>
      <sshPrnamt>781404</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>712322</Shared>
      <None>69082</None>
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    <nameOfIssuer>MID-AMERICA APARTMENT COMMUNIT</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>59522J103</cusip>
    <figi>BBG000BLMY92</figi>
    <value>27229325</value>
    <shrsOrPrnAmt>
      <sshPrnamt>194871</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>194871</Shared>
      <None>0</None>
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    <nameOfIssuer>MINERALS TECHNOLOGIES INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>603158106</cusip>
    <figi>BBG000BB61F7</figi>
    <value>35050216</value>
    <shrsOrPrnAmt>
      <sshPrnamt>564234</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>514340</Shared>
      <None>49894</None>
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  <infoTable>
    <nameOfIssuer>NNN REIT INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>637417106</cusip>
    <figi>BBG000CLP0Y4</figi>
    <value>32101569</value>
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      <sshPrnamt>754089</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>754089</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>PDF SOLUTIONS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>693282105</cusip>
    <figi>BBG000CYCKR4</figi>
    <value>20665218</value>
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      <sshPrnamt>800357</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>729554</Shared>
      <None>70803</None>
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  <infoTable>
    <nameOfIssuer>POWER INTEGRATIONS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>739276103</cusip>
    <figi>BBG000BTT3D1</figi>
    <value>33363282</value>
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      <sshPrnamt>829726</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>755357</Shared>
      <None>74369</None>
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  <infoTable>
    <nameOfIssuer>PROSPERITY BANCSHARES INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>743606105</cusip>
    <figi>BBG000BHY4D9</figi>
    <value>75601711</value>
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      <sshPrnamt>1139438</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>1077663</Shared>
      <None>61775</None>
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  <infoTable>
    <nameOfIssuer>RBC BEARINGS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>75524B104</cusip>
    <figi>BBG000GMGNB3</figi>
    <value>127328600</value>
    <shrsOrPrnAmt>
      <sshPrnamt>326241</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>309627</Shared>
      <None>16614</None>
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  <infoTable>
    <nameOfIssuer>RENTOKIL INITIAL PLC SPONSORED</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>760125104</cusip>
    <figi>BBG000BVPG41</figi>
    <value>37583893</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1488471</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>1488471</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>RLI CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>749607107</cusip>
    <figi>BBG000BS7ZF4</figi>
    <value>26064129</value>
    <shrsOrPrnAmt>
      <sshPrnamt>399634</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>364289</Shared>
      <None>35345</None>
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  <infoTable>
    <nameOfIssuer>SENSIENT TECHNOLOGIES CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>81725T100</cusip>
    <figi>BBG000J79P80</figi>
    <value>62453703</value>
    <shrsOrPrnAmt>
      <sshPrnamt>665463</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>606623</Shared>
      <None>58840</None>
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  <infoTable>
    <nameOfIssuer>SIMPSON MANUFACTURING</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>829073105</cusip>
    <figi>BBG000JLC8L8</figi>
    <value>37384775</value>
    <shrsOrPrnAmt>
      <sshPrnamt>223246</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>203502</Shared>
      <None>19744</None>
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  <infoTable>
    <nameOfIssuer>SS&amp;C  TECHNOLOGIES HOLDINGS IN</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>78467J100</cusip>
    <figi>BBG000RJ2J04</figi>
    <value>168456894</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1897892</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>1897892</Shared>
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  <infoTable>
    <nameOfIssuer>STERIS PLC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>G8473T100</cusip>
    <figi>BBG00MRHG523</figi>
    <value>36712178</value>
    <shrsOrPrnAmt>
      <sshPrnamt>148368</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>148368</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>THERMO FISHER SCIENTIFIC INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>883556102</cusip>
    <figi>BBG000BVDLH9</figi>
    <value>47670191</value>
    <shrsOrPrnAmt>
      <sshPrnamt>98285</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>98285</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>UGI CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>902681105</cusip>
    <figi>BBG000BVYN55</figi>
    <value>178077931</value>
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      <sshPrnamt>5354117</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>5190119</Shared>
      <None>163998</None>
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  <infoTable>
    <nameOfIssuer>UNITED COMMUNITY BANKS INC  OF</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>90984P303</cusip>
    <figi>BBG000BL7GB5</figi>
    <value>53579877</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1709087</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>1557960</Shared>
      <None>151127</None>
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  <infoTable>
    <nameOfIssuer>VALVOLINE INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>92047W101</cusip>
    <figi>BBG003DNHV56</figi>
    <value>62503438</value>
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      <sshPrnamt>1740558</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>1586795</Shared>
      <None>153763</None>
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  <infoTable>
    <nameOfIssuer>VERRA MOBILITY CORP CL A</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>92511U102</cusip>
    <figi>BBG00G4XQ9Z1</figi>
    <value>53605916</value>
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      <sshPrnamt>2170280</sshPrnamt>
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      <Sole>0</Sole>
      <Shared>1975242</Shared>
      <None>195038</None>
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  <infoTable>
    <nameOfIssuer>VISA INC CL A</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>92826C839</cusip>
    <figi>BBG000PSKYX7</figi>
    <value>63812456</value>
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      <sshPrnamt>186925</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>186925</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>WASTE CONNECTIONS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>94106B101</cusip>
    <figi>BBG000FLHZZ2</figi>
    <value>135268607</value>
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      <sshPrnamt>769446</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
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      <Sole>0</Sole>
      <Shared>769446</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>WEX INC.</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>96208T104</cusip>
    <figi>BBG000BVZP59</figi>
    <value>27635015</value>
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      <sshPrnamt>175427</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>175427</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>WOODWARD INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>980745103</cusip>
    <figi>BBG000BD53V2</figi>
    <value>128052958</value>
    <shrsOrPrnAmt>
      <sshPrnamt>506719</sshPrnamt>
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    <investmentDiscretion>DFND</investmentDiscretion>
    <votingAuthority>
      <Sole>0</Sole>
      <Shared>478502</Shared>
      <None>28217</None>
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  </infoTable>
</informationTable>
