Zerodha's billionaire Co-founder Nikhil Kamath has become a pledger for 'The Giving Pledge'. Launched by Warren Buffett, Melinda French Gates and Bill Gates, it's an open invitation for billionaires to publicly commit to giving the majority of their wealth to philanthropy. Kamath is the fourth Indian after Azim Premji, Kiran Mazumdar-Shaw, Rohini and Nandan Nilekani to take the pledge.