Nikhil Kamath, 35, the co-founder of Zerodha, India’s biggest stock brokerage in terms of volume of trade, has signed the Giving Pledge, an initiative that was founded by Warren Buffet, Bill Gates and Melinda French Gates in 2010. The Pledge is a global commitment made by wealthy individuals and their families to give away a majority of their wealth towards charitable causes, either during their lifetime or in their wills.