Stephen Schwarzman

The son of a dry goods store owner, Stephen Schwarzman founded private equity firm Blackstone with fellow billionaire Peter Peterson in 1985. Initially a boutique merger-and-acquisition advisory business, Blackstone grew into the world's largest buyout firm, with $439 billion in assets. While Peter Peterson retired shortly after Blackstone's 2007 IPO, Schwarzman still presides over the business as chairman and CEO.He has pledged or given away a combined $350 million to Yale University, New York Public Library and others.