"The only Asian in the Top 10, Ambani's wealth is based on telecom, retail and energy, and bucked the poor stock market trend in India last year," Hurun Research said in a statement.
The Hurun Global Rich List 2019 is topped by Amazon chief Jeff Bezos for the second year in a row, while the senior Ambani is placed 10th with a network of Rs 3.83 trillion, thanks to a rally in RIL shares, which had topped the Rs 8-lakh-crore-mark last month. Ambani owns almost 52 percent in Reliance.
Anil Ambani, held in contempt of court by the Supreme Court last week for not paying up Ericsson Rs 540 crore, has lost over $5 billion, from $7 billion seven years ago to $1.9 billion this year, even though both the brothers got off with more or less same amount of inherited wealth.
"Having started off similarly after the break-up of the family wealth, Mukesh added $30 billion to his wealth in the past seven years, while Anil has lost over $5 billion during the same period," says the Hurun report.
Other individuals from India who were named in the list include S P Hinduja (40th), Azim Premji (57) and Cyrus Poonawalla.
Cyrus S Poonawalla, chairman of the Poonawalla group that run Serum Institute, with a networth of $13 billion is not only ranked as the fourth richest Indian but also breaks into the top 100 global ranking.
Steel giant ArcelorMittal's Lakshmi Mittal stands at fifth position, followed by Kotak Mahindra's Uday Kotak ($11 billion), Gautam Adani ($9.9 billion) and Sun Pharma's Dilip Shanghvi ($9.5 billion).
Cyrus Pallonji Mistry and Shapoorji Pallonji Mistry, both with wealth of$9.5 billion each come in the ninth and the 10th position, respectively, thanks to their 18.4 percent holding in the country's largest conglomerate Tata group.
According to the list, Smita Crishna, a third- generation heir of the Godrej family, tops the female billionaire list with a networth of USD 6.1 billion, while Kiran Mazumdar Shaw of Biocon is the richest self-made female entrepreneur ranked 671 with a wealth of USD 3.5 billion.
"Since 2012, this is for that first time that India has slipped to the fifth rank in the Hurun Global Rich List. An underperforming rupee and a lackluster stock market resulted in the country losing one-third of the list," Hurun Report India managing director and chief researcher Anas Rahman Junaid said.
The report also points out that media billionaires had a bad year, led by Zee's Subhash Chandra and Sun TV's Kalanithi Maran who lost their networth substantially.
As per the report, the number of individuals featured in the 2019 edition has come down by 224 to 2,470 from 2,694 in 2018.
At 658, China has the highest number of billionaires, the report showed. Of the total 2,470 undividuals, 584 are from the US and 117 from Germany.
Amazon's Jeff Bezos retained the top spot in the list with a net worth of $147 billion. His wealtgh rose by $24 billion in 2018.
"Pharmaceuticals, TMT and FMCG led the way, with 18, 15 and 10 billionaires each. Mumbai and New Delhi are the billionaire capitals of the country with 42 and 25 finding residence there.
"The average age was 62, 2 less than the average of the total list. Total wealth is $347 billion. Indian billionaires lost one-fourth of their wealth amounting to $107 billion; 28 lost their billionaire status owing to 10 per cent depreciation of the rupee and below average performance of the capital market," Hurun Research said.