Tycoon's construction giant, Shapoorji Pallonji Group, run by older son Shapoor, is celebrating its 150th anniversary this year. Its real estate arm recently partnered with Standard Chartered Private Equity, the International Finance Corp. and the Asian Development Bank in a $200 million venture to build 20,000 affordable homes. Mistry's biggest source of wealth remains his 18.4% stake in Tata Sons, the holding company for the $109 billion (revenues) Tata Group, chaired by younger son Cyrus.