How the fortunes of Ambani brothers have grown about $40 billion apart

The tale of the two brothers' diverging fortunes began 16 years ago, when their rags-to-riches father Dhirubhai Ambani, whose life inspired a Bollywood film, died of a stroke without leaving a will

Over the past year, the fortunes of the two brothers at the helm of India’s wealthiest dynasty have grown apart -- to about $40 billion apart.

Elder sibling Mukesh Ambani, 61, toppled China’s Jack Ma as Asia’s richest man, after driving a telecommunications revolution in India that propelled his petrochemicals conglomerate Reliance Industries Ltd. into the $100 billion club. His personal fortune had swollen to more than $40 billion as of Friday, according to the Bloomberg Billionaires Index, billions ahead of Ma and at similar levels to Microsoft Corp.’s former chief, Steve Ballmer.

Meanwhile, Anil Ambani, two years his junior,