A majority of India's billionaires gained wealth in the last one year in spite of the stock market decline.
In the Forbes rich list Mukesh Ambani is ranked 39th.
The combined networth of India's 100 wealthiest is $381 billion (nearly Rs 25.5 lakh crore), a rise of 10 per cent from $ 345 billion in 2015
The biotech company's revenues had fallen to as low as Rs 50 cr.
Indian billionaires do not believe in sitting on their wealth.