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    <nameOfIssuer>ADAPTIVE BIOTECHNOLOGIES COR</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>00650F109</cusip>
    <value>22033</value>
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      <Sole>793125</Sole>
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      <None>0</None>
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    <nameOfIssuer>ADVERUM BIOTECHNOLOGIES INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>00773U108</cusip>
    <value>10991</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1125000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <votingAuthority>
      <Sole>1125000</Sole>
      <Shared>0</Shared>
      <None>0</None>
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    <nameOfIssuer>AGIOS PHARMACEUTICALS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>00847X104</cusip>
    <value>37964</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1070000</sshPrnamt>
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    <votingAuthority>
      <Sole>1070000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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    <nameOfIssuer>ALECTOR INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>014442107</cusip>
    <value>25965</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1076039</sshPrnamt>
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      <Sole>1076039</Sole>
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      <None>0</None>
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    <nameOfIssuer>ALLOGENE THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>019770106</cusip>
    <value>9720</value>
    <shrsOrPrnAmt>
      <sshPrnamt>500000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>500000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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  <infoTable>
    <nameOfIssuer>ALNYLAM PHARMACEUTICALS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>02043Q107</cusip>
    <value>63677</value>
    <shrsOrPrnAmt>
      <sshPrnamt>585000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <votingAuthority>
      <Sole>585000</Sole>
      <Shared>0</Shared>
      <None>0</None>
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  <infoTable>
    <nameOfIssuer>BLACK DIAMOND THERAPEUTICS I</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>09203E105</cusip>
    <value>7220</value>
    <shrsOrPrnAmt>
      <sshPrnamt>289395</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>289395</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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  <infoTable>
    <nameOfIssuer>BIOLIFE SOLUTIONS INC</nameOfIssuer>
    <titleOfClass>COM NEW</titleOfClass>
    <cusip>09062W204</cusip>
    <value>23451</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2468571</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>SOLE</investmentDiscretion>
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      <Sole>2468571</Sole>
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      <None>0</None>
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    <nameOfIssuer>BLUEBIRD BIO INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>09609G100</cusip>
    <value>50786</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1105000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1105000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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    <nameOfIssuer>BRISTOL-MYERS SQUIBB CO</nameOfIssuer>
    <titleOfClass>RIGHT</titleOfClass>
    <cusip>110122157</cusip>
    <value>9500</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2500000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2500000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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  <infoTable>
    <nameOfIssuer>BLUEPRINT MEDICINES CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>09627Y109</cusip>
    <value>90644</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1550000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1550000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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    <nameOfIssuer>CAREDX INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>14167L103</cusip>
    <value>28255</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1294335</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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      <Sole>1294335</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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    <nameOfIssuer>CODEXIS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>192005106</cusip>
    <value>56623</value>
    <shrsOrPrnAmt>
      <sshPrnamt>5073780</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>5073780</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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    <nameOfIssuer>CONSTELLATION PHARMCETICLS I</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>210373106</cusip>
    <value>30801</value>
    <shrsOrPrnAmt>
      <sshPrnamt>980000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>980000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
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    <nameOfIssuer>CRISPR THERAPEUTICS AG</nameOfIssuer>
    <titleOfClass>NAMEN AKT</titleOfClass>
    <cusip>H17182108</cusip>
    <value>11299</value>
    <shrsOrPrnAmt>
      <sshPrnamt>266430</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>266430</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>DECIPHERA PHARMACEUTICALS IN</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>24344T101</cusip>
    <value>5764</value>
    <shrsOrPrnAmt>
      <sshPrnamt>140000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>140000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
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    <nameOfIssuer>DERMTECH INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>24984K105</cusip>
    <value>5642</value>
    <shrsOrPrnAmt>
      <sshPrnamt>571713</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>571713</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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  <infoTable>
    <nameOfIssuer>DENALI THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>24823R105</cusip>
    <value>25477</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1455000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1455000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>FATE THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>31189P102</cusip>
    <value>56636</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2550000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2550000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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  <infoTable>
    <nameOfIssuer>FULCRUM THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>359616109</cusip>
    <value>14439</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1209285</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1209285</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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    <nameOfIssuer>GLOBAL BLOOD THERAPEUTICS IN</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>37890U108</cusip>
    <value>15327</value>
    <shrsOrPrnAmt>
      <sshPrnamt>300000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>300000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>GILEAD SCIENCES INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>375558103</cusip>
    <value>13083</value>
    <shrsOrPrnAmt>
      <sshPrnamt>175000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>175000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>GENMARK DIAGNOSTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>372309104</cusip>
    <value>13864</value>
    <shrsOrPrnAmt>
      <sshPrnamt>3365000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>3365000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>GRITSTONE ONCOLOGY INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>39868T105</cusip>
    <value>13211</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2270000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2270000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>ILLUMINA INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>452327109</cusip>
    <value>8194</value>
    <shrsOrPrnAmt>
      <sshPrnamt>30000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>30000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>MAGENTA THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>55910K108</cusip>
    <value>18658</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2971034</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2971034</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>MYOKARDIA INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>62857M105</cusip>
    <value>46646</value>
    <shrsOrPrnAmt>
      <sshPrnamt>995000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>995000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>INVITAE CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>46185L103</cusip>
    <value>47550</value>
    <shrsOrPrnAmt>
      <sshPrnamt>3478388</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>3478388</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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  <infoTable>
    <nameOfIssuer>ORCHARD THERAPEUTICS PLC</nameOfIssuer>
    <titleOfClass>ADS</titleOfClass>
    <cusip>68570P101</cusip>
    <value>7342</value>
    <shrsOrPrnAmt>
      <sshPrnamt>975000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>975000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>REVOLUTION MEDICINES INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>76155X100</cusip>
    <value>28911</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1319536</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1319536</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>SAGE THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>78667J108</cusip>
    <value>11057</value>
    <shrsOrPrnAmt>
      <sshPrnamt>385000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>385000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>SANGAMO THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>800677106</cusip>
    <value>9268</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1455000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1455000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>SAREPTA THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>803607100</cusip>
    <value>65539</value>
    <shrsOrPrnAmt>
      <sshPrnamt>670000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>670000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>STOKE THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>86150R107</cusip>
    <value>2748</value>
    <shrsOrPrnAmt>
      <sshPrnamt>120000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>120000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>TURNING POINT THERAPEUTICS I</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>90041T108</cusip>
    <value>3350</value>
    <shrsOrPrnAmt>
      <sshPrnamt>75000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>75000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>TWIST BIOSCIENCE CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>90184D100</cusip>
    <value>30580</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1000000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1000000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
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  <infoTable>
    <nameOfIssuer>VOYAGER THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>92915B106</cusip>
    <value>10020</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1095075</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
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    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1095075</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>ZAI LAB LTD</nameOfIssuer>
    <titleOfClass>ADR</titleOfClass>
    <cusip>98887Q104</cusip>
    <value>9781</value>
    <shrsOrPrnAmt>
      <sshPrnamt>190000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>190000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
</informationTable>
