<informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable">		<infoTable>
			<nameOfIssuer>AERCAP HOLDINGS NV</nameOfIssuer>
			<titleOfClass>SHS</titleOfClass>
			<cusip>N00985106</cusip>
			<value>17171</value>
			<shrsOrPrnAmt>
				<sshPrnamt>375000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>375000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>AGENUS INC</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>00847G705</cusip>
			<value>4575</value>
			<shrsOrPrnAmt>
				<sshPrnamt>530090</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>530090</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>AGIOS PHARMACEUTICALS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>00847X104</cusip>
			<value>17782</value>
			<shrsOrPrnAmt>
				<sshPrnamt>160000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>160000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ALIBABA GROUP HLDG LTD</nameOfIssuer>
			<titleOfClass>SPONSORED ADS</titleOfClass>
			<cusip>01609W102</cusip>
			<value>41135</value>
			<shrsOrPrnAmt>
				<sshPrnamt>500000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>500000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ALIBABA GROUP HLDG LTD</nameOfIssuer>
			<titleOfClass>SPONSORED ADS</titleOfClass>
			<cusip>01609W102</cusip>
			<value>8227</value>
			<shrsOrPrnAmt>
				<sshPrnamt>100000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>100000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ALNYLAM PHARMACEUTICALS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>02043Q107</cusip>
			<value>54541</value>
			<shrsOrPrnAmt>
				<sshPrnamt>455000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>455000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>AMAZON COM INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>023135106</cusip>
			<value>28216</value>
			<shrsOrPrnAmt>
				<sshPrnamt>65000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>65000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>AMERICAN AIRLS GROUP INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>02376R102</cusip>
			<value>15974</value>
			<shrsOrPrnAmt>
				<sshPrnamt>400000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>400000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>AMERICAN AIRLS GROUP INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>02376R102</cusip>
			<value>9984</value>
			<shrsOrPrnAmt>
				<sshPrnamt>250000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>250000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>AMERICAN EXPRESS CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>025816109</cusip>
			<value>34974</value>
			<shrsOrPrnAmt>
				<sshPrnamt>450000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>450000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ARRAY BIOPHARMA INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>04269X105</cusip>
			<value>26749</value>
			<shrsOrPrnAmt>
				<sshPrnamt>3710000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>3710000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ARRAY BIOPHARMA INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>04269X105</cusip>
			<value>2163</value>
			<shrsOrPrnAmt>
				<sshPrnamt>300000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>300000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BANK AMER CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>060505104</cusip>
			<value>17020</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1000000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>1000000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BANK AMER CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>060505104</cusip>
			<value>42550</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2500000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>2500000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BIOGEN INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>09062X103</cusip>
			<value>141379</value>
			<shrsOrPrnAmt>
				<sshPrnamt>350000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>350000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BIOMARIN PHARMACEUTICAL INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>09061G101</cusip>
			<value>59499</value>
			<shrsOrPrnAmt>
				<sshPrnamt>435000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>435000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BIOMARIN PHARMACEUTICAL INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>09061G101</cusip>
			<value>27356</value>
			<shrsOrPrnAmt>
				<sshPrnamt>200000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>200000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BIOTIME INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>09066L105</cusip>
			<value>4654</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1282050</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>1282050</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BIOTIME INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>09066L105</cusip>
			<value>2178</value>
			<shrsOrPrnAmt>
				<sshPrnamt>600000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>600000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BLUEBIRD BIO INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>09609G100</cusip>
			<value>33674</value>
			<shrsOrPrnAmt>
				<sshPrnamt>200000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>200000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CASTLIGHT HEALTH INC</nameOfIssuer>
			<titleOfClass>CL B</titleOfClass>
			<cusip>14862Q100</cusip>
			<value>2035</value>
			<shrsOrPrnAmt>
				<sshPrnamt>250000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>250000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CELGENE CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>151020104</cusip>
			<value>69441</value>
			<shrsOrPrnAmt>
				<sshPrnamt>600000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>600000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CELLDEX THERAPEUTICS INC NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>15117B103</cusip>
			<value>6305</value>
			<shrsOrPrnAmt>
				<sshPrnamt>250000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>250000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CELLECTIS S A</nameOfIssuer>
			<titleOfClass>SPONSORED ADS</titleOfClass>
			<cusip>15117K103</cusip>
			<value>4510</value>
			<shrsOrPrnAmt>
				<sshPrnamt>125000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>125000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CERES INC</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>156773400</cusip>
			<value>1997</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1024020</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4</otherManager>
			<votingAuthority>
				<Sole>1024020</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CHEMOCENTRYX INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>16383L106</cusip>
			<value>7407</value>
			<shrsOrPrnAmt>
				<sshPrnamt>900000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>900000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CITIGROUP INC</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>172967424</cusip>
			<value>22096</value>
			<shrsOrPrnAmt>
				<sshPrnamt>400000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>400000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>COLUCID PHARMACEUTICALS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>19716T101</cusip>
			<value>50</value>
			<shrsOrPrnAmt>
				<sshPrnamt>5575</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4</otherManager>
			<votingAuthority>
				<Sole>5575</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CROWN CASTLE INTL CORP NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>22822V101</cusip>
			<value>16060</value>
			<shrsOrPrnAmt>
				<sshPrnamt>200000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>200000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>DELTA AIR LINES INC DEL</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>247361702</cusip>
			<value>8216</value>
			<shrsOrPrnAmt>
				<sshPrnamt>200000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>200000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>GENERAL ELECTRIC CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>369604103</cusip>
			<value>53140</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2000000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>2000000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>GENERAL MTRS CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>37045V100</cusip>
			<value>14999</value>
			<shrsOrPrnAmt>
				<sshPrnamt>450000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>450000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>GENERAL MTRS CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>37045V100</cusip>
			<value>33330</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1000000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>1000000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>GILEAD SCIENCES INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>375558103</cusip>
			<value>11708</value>
			<shrsOrPrnAmt>
				<sshPrnamt>100000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>100000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>GOLDMAN SACHS GROUP INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>38141G104</cusip>
			<value>62637</value>
			<shrsOrPrnAmt>
				<sshPrnamt>300000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>300000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>GOOGLE INC</nameOfIssuer>
			<titleOfClass>CL C</titleOfClass>
			<cusip>38259P706</cusip>
			<value>117115</value>
			<shrsOrPrnAmt>
				<sshPrnamt>225000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>225000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>HILTON WORLDWIDE HLDGS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>43300A104</cusip>
			<value>15153</value>
			<shrsOrPrnAmt>
				<sshPrnamt>550000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>550000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>IGNYTA INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>451731103</cusip>
			<value>6791</value>
			<shrsOrPrnAmt>
				<sshPrnamt>450000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>450000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>INCYTE CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>45337C102</cusip>
			<value>50021</value>
			<shrsOrPrnAmt>
				<sshPrnamt>480000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>480000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>IRONWOOD PHARMACEUTICALS INC</nameOfIssuer>
			<titleOfClass>COM CL A</titleOfClass>
			<cusip>46333X108</cusip>
			<value>2616</value>
			<shrsOrPrnAmt>
				<sshPrnamt>216879</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4</otherManager>
			<votingAuthority>
				<Sole>216879</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ISIS PHARMACEUTICALS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>464330109</cusip>
			<value>23020</value>
			<shrsOrPrnAmt>
				<sshPrnamt>400000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>400000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>JD COM INC</nameOfIssuer>
			<titleOfClass>SPON ADR CL A</titleOfClass>
			<cusip>47215P106</cusip>
			<value>3410</value>
			<shrsOrPrnAmt>
				<sshPrnamt>100000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>100000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>JPMORGAN CHASE &amp; CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>46625H100</cusip>
			<value>40656</value>
			<shrsOrPrnAmt>
				<sshPrnamt>600000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>600000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>JUMEI INTL HLDG LTD</nameOfIssuer>
			<titleOfClass>SPONSORED ADR</titleOfClass>
			<cusip>48138L107</cusip>
			<value>11420</value>
			<shrsOrPrnAmt>
				<sshPrnamt>500000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>500000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>JUNO THERAPEUTICS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>48205A109</cusip>
			<value>10133</value>
			<shrsOrPrnAmt>
				<sshPrnamt>190000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>190000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>KITE PHARMA INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>49803L109</cusip>
			<value>25912</value>
			<shrsOrPrnAmt>
				<sshPrnamt>425000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>425000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LENDINGCLUB CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>52603A109</cusip>
			<value>15856</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1075000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>1075000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LENDINGCLUB CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>52603A109</cusip>
			<value>3688</value>
			<shrsOrPrnAmt>
				<sshPrnamt>250000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>250000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LEXICON PHARMACEUTICALS INC</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>528872302</cusip>
			<value>6386</value>
			<shrsOrPrnAmt>
				<sshPrnamt>793327</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>793327</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LEXICON PHARMACEUTICALS INC</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>528872302</cusip>
			<value>456633</value>
			<shrsOrPrnAmt>
				<sshPrnamt>56724651</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4</otherManager>
			<votingAuthority>
				<Sole>56724651</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LINKEDIN CORP</nameOfIssuer>
			<titleOfClass>COM CL A</titleOfClass>
			<cusip>53578A108</cusip>
			<value>27172</value>
			<shrsOrPrnAmt>
				<sshPrnamt>131500</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>131500</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MASTERCARD INC</nameOfIssuer>
			<titleOfClass>CL A</titleOfClass>
			<cusip>57636Q104</cusip>
			<value>37392</value>
			<shrsOrPrnAmt>
				<sshPrnamt>400000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>400000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MCDONALDS CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>580135101</cusip>
			<value>19014</value>
			<shrsOrPrnAmt>
				<sshPrnamt>200000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>200000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MERCK &amp; CO INC NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>58933Y105</cusip>
			<value>28465</value>
			<shrsOrPrnAmt>
				<sshPrnamt>500000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>500000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>METLIFE INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>59156R108</cusip>
			<value>33594</value>
			<shrsOrPrnAmt>
				<sshPrnamt>600000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>600000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MICRON TECHNOLOGY INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>595112103</cusip>
			<value>18840</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1000000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>1000000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MIRATI THERAPEUTICS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>60468T105</cusip>
			<value>1928</value>
			<shrsOrPrnAmt>
				<sshPrnamt>61276</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>61276</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MOBILEYE N V AMSTELVEEN</nameOfIssuer>
			<titleOfClass>ORD SHS</titleOfClass>
			<cusip>N51488117</cusip>
			<value>26585</value>
			<shrsOrPrnAmt>
				<sshPrnamt>500000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>500000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MORGAN STANLEY</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>617446448</cusip>
			<value>29093</value>
			<shrsOrPrnAmt>
				<sshPrnamt>750000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>750000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NEKTAR THERAPEUTICS</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>640268108</cusip>
			<value>21267</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1700000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>1700000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PARNELL PHARMACEUT HLDGS LTD</nameOfIssuer>
			<titleOfClass>SHS</titleOfClass>
			<cusip>Q73622104</cusip>
			<value>2475</value>
			<shrsOrPrnAmt>
				<sshPrnamt>500000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>500000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>QUALCOMM INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>747525103</cusip>
			<value>31315</value>
			<shrsOrPrnAmt>
				<sshPrnamt>500000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>500000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>REALOGY HLDGS CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>75605Y106</cusip>
			<value>4672</value>
			<shrsOrPrnAmt>
				<sshPrnamt>100000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>100000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SERES THERAPEUTICS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>81750R102</cusip>
			<value>6642</value>
			<shrsOrPrnAmt>
				<sshPrnamt>160057</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>160057</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TEVA PHARMACEUTICAL INDS LTD</nameOfIssuer>
			<titleOfClass>ADR</titleOfClass>
			<cusip>881624209</cusip>
			<value>26595</value>
			<shrsOrPrnAmt>
				<sshPrnamt>450000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>450000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WAL-MART STORES INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>931142103</cusip>
			<value>118098</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1665000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<putCall>Call</putCall>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1,2,3,4,5</otherManager>
			<votingAuthority>
				<Sole>1665000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WEIGHT WATCHERS INTL INC NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>948626106</cusip>
			<value>142800</value>
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		<infoTable>
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		<infoTable>
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		<infoTable>
			<nameOfIssuer>YUM BRANDS INC</nameOfIssuer>
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		<infoTable>
			<nameOfIssuer>YY INC</nameOfIssuer>
			<titleOfClass>ADS REPCOM CLA</titleOfClass>
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</informationTable>
