With his net worth of $137.4 billion, Adani now ranks just behind Tesla CEO Elon Musk and Amazon founder Jeff Bezos.
Indian industrialist Gautam Adani has become the world's third-richest person on the Bloomberg Billionaires Index, the first time an Asian has ranked in the top three.
The self-made billionaire has seen his net worth more than double to $137.4 billion in the last year, rising 20 spots on the index to now rank just behind Elon Musk and Jeff Bezos, Bloomberg News reported on Tuesday.
Adani, 60, made his fortune in ports and commodities trading and now operates India's third-largest conglomerate with interests ranging from coal mining and edible oils to airports and news media.
His ballooning net worth reflects a stratospheric rise in the market capitalisation of his publicly listed companies, as investors back the Adani Group's aggressive expansion of old and new businesses.
Shares in the flagship Adani Enterprises – of which the billionaire owns 75 percent – have soared more than 2,400 percent since March 2020, and doubled in value in the past six months.
Stock price surges in other group companies including Adani Transmission, Adani Power, Adani Ports and Adani Green Energy have catapulted Adani past fellow Indian billionaire Mukesh Ambani.
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Born in the city of Ahmedabad in the western state of Gujarat to a middle-class family, Adani dropped out of college to work briefly in the diamond industry before starting his export business in 1988.
In 1995, he won a contract to build and operate a commercial shipping port at Mundra in Gujarat, which has since grown to become India's largest port.
At the same time, Adani expanded into thermal power generation and coal mining in India and overseas.
In recent years, the conglomerate has forayed into petrochemicals, cement, data centres and copper refining, in addition to establishing a renewable energy business with ambitious targets.
Recent investments in Indian news media and a bid for 5G airwaves this year have raised speculation that the billionaire's empire could soon impinge on sectors dominated by Ambani's Reliance Industries.
But Adani's rapid expansion into capital-intensive businesses has raised alarm, with Fitch Group's CreditSights warning last week that the group is "deeply overleveraged".
"In the worst-case scenario, overly ambitious debt-funded growth plans could eventually spiral into a massive debt trap, and possibly culminate into a distressed situation or default," the credit market research firm said in a note.
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