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       <nameOfIssuer>QURATE RETAIL INC</nameOfIssuer>
       <titleOfClass>COM SER A</titleOfClass>
       <cusip>74915M100</cusip>
       <value>2766</value>
       <shrsOrPrnAmt>
           <sshPrnamt>453031</sshPrnamt>
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       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
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           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
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   <infoTable>
       <nameOfIssuer>ALPHABET INC</nameOfIssuer>
       <titleOfClass>CAP STK CL C</titleOfClass>
       <cusip>02079K107</cusip>
       <value>6051</value>
       <shrsOrPrnAmt>
           <sshPrnamt>5204</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
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   <infoTable>
       <nameOfIssuer>WESTERN DIGITAL CORP</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>958102105</cusip>
       <value>3163</value>
       <shrsOrPrnAmt>
           <sshPrnamt>76000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
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   <infoTable>
       <nameOfIssuer>CITIGROUP INC</nameOfIssuer>
       <titleOfClass>COM NEW</titleOfClass>
       <cusip>172967424</cusip>
       <value>3243</value>
       <shrsOrPrnAmt>
           <sshPrnamt>77000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
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       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
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           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
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   <infoTable>
       <nameOfIssuer>EQUINIX INC</nameOfIssuer>
       <titleOfClass>COM PAR $0.001</titleOfClass>
       <cusip>29444U700</cusip>
       <value>3080</value>
       <shrsOrPrnAmt>
           <sshPrnamt>4932</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
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       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>GAMESTOP CORP NEW</nameOfIssuer>
       <titleOfClass>CL A</titleOfClass>
       <cusip>36467W109</cusip>
       <value>9888</value>
       <shrsOrPrnAmt>
           <sshPrnamt>2825000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
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       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
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   <infoTable>
       <nameOfIssuer>GOLDMAN SACHS GROUP INC</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>38141G104</cusip>
       <value>495</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3200</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>INTERDIGITAL INC</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>45867G101</cusip>
       <value>6639</value>
       <shrsOrPrnAmt>
           <sshPrnamt>148750</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
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       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
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   <infoTable>
       <nameOfIssuer>MGIC INVT CORP WIS</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>552848103</cusip>
       <value>3874</value>
       <shrsOrPrnAmt>
           <sshPrnamt>610000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>PEABODY ENERGY CORP.</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>704551100</cusip>
       <value>110</value>
       <shrsOrPrnAmt>
           <sshPrnamt>38000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>SBA COMMUNICATIONS CORP</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>78410G104</cusip>
       <value>189507</value>
       <shrsOrPrnAmt>
           <sshPrnamt>701954</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>VIACOM INC NEW</nameOfIssuer>
       <titleOfClass>CL B</titleOfClass>
       <cusip>92556H206</cusip>
       <value>3096</value>
       <shrsOrPrnAmt>
           <sshPrnamt>220994</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>WILLIAMS COS INC DEL</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>969457100</cusip>
       <value>991</value>
       <shrsOrPrnAmt>
           <sshPrnamt>70000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ALPHABET INC</nameOfIssuer>
       <titleOfClass>CAP STK CL A</titleOfClass>
       <cusip>02079K305</cusip>
       <value>697</value>
       <shrsOrPrnAmt>
           <sshPrnamt>600</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>BERKSHIRE HATHAWAY INC DEL</nameOfIssuer>
       <titleOfClass>CL A</titleOfClass>
       <cusip>084670108</cusip>
       <value>544</value>
       <shrsOrPrnAmt>
           <sshPrnamt>2</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>BERKSHIRE HATHAWAY INC DEL</nameOfIssuer>
       <titleOfClass>CL B NEW</titleOfClass>
       <cusip>084670702</cusip>
       <value>608</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3325</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>BROWN FORMAN CORP</nameOfIssuer>
       <titleOfClass>CL A</titleOfClass>
       <cusip>115637100</cusip>
       <value>154</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>BROWN FORMAN CORP</nameOfIssuer>
       <titleOfClass>CL B</titleOfClass>
       <cusip>115637209</cusip>
       <value>102</value>
       <shrsOrPrnAmt>
           <sshPrnamt>1843</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>JPMORGAN CHASE &amp; CO</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>46625H100</cusip>
       <value>381</value>
       <shrsOrPrnAmt>
           <sshPrnamt>4235</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
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   <infoTable>
       <nameOfIssuer>CVS HEALTH CORP</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>126650100</cusip>
       <value>2700</value>
       <shrsOrPrnAmt>
           <sshPrnamt>45500</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
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           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>MASTERCARD INC</nameOfIssuer>
       <titleOfClass>CL A</titleOfClass>
       <cusip>57636Q104</cusip>
       <value>1220</value>
       <shrsOrPrnAmt>
           <sshPrnamt>5050</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>PHILIP MORRIS INTL INC</nameOfIssuer>
       <titleOfClass>COM</titleOfClass>
       <cusip>718172109</cusip>
       <value>558</value>
       <shrsOrPrnAmt>
           <sshPrnamt>7645</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>UNILEVER NV</nameOfIssuer>
       <titleOfClass>NY SHS NEW</titleOfClass>
       <cusip>904784709</cusip>
       <value>533</value>
       <shrsOrPrnAmt>
           <sshPrnamt>10925</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>VISA INC</nameOfIssuer>
       <titleOfClass>COM CL A</titleOfClass>
       <cusip>92826C839</cusip>
       <value>516</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3200</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <otherManager>1</otherManager>
       <votingAuthority>
           <Sole>0</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
</informationTable>
