WASHINGTON: India's billionaire Gautam Adani has been ranked as the fourth richest person in the world by Forbes' Real Time Billionaires List. According to the list, Adani has a net worth of $116.3 billion, while Bill Gates' net worth stands at $104.7 billion. Reliance Industries (RIL) chairman and managing director Mukesh Ambani has been ranked on the 10th spot with a net worth of $90 billion.

Gates is believed to have slipped in the rankings after he announced that he would donate $20 billion from his wealth to his non-profit organization. The richest woman on the list is L'Oreal's Francoise Bettencourt Meyers and family with a net worth of $71 billion. She is placed on the 15th spot. The Indian tycoon has added $36 billion to his fortune this year, more than anyone else, while Gates's has shrunk as he sped up philanthropic giving and tech shares sold off.

Adani, who built his empire on agri-trading, coal and ports, has been moving up a wealth ranking traditionally dominated by US tech entrepreneurs. He's been rapidly diversifying into green energy, airports, data centers, digital services and media, aligning his strategy with Indian Prime Minister Narendra Modi's 'nation-building agenda'.

The first-generation entrepreneur and college dropout, Adani started off with an agri-trading firm in the late 1980s has amassed almost all of his wealth in the past two years as his push to diversify intensified. He became a centibillionaire in April, joining the elite club that includes people Elon Musk and Jeff Bezos. In November, he pledged to invest $70 billion across the green energy value chain by 2030 - a commitment that's often criticised by environmentalists given his group's investment in developing the Carmichael coal mine project in Australia. - Agencies