Carl Celian Icahn is an American businessman, investor, and philanthropist. He is the founder and controlling shareholder of Icahn Enterprises, a public company and diversified conglomerate holding company based in Sunny Isles Beach, Florida. Icahn's business model is to take large stakes in companies that he believes will appreciate from changes to corporate policy. Subsequently, Icahn then pressures management to make the changes that he believes will benefit shareholders. Widely regarded as one of the most successful hedge fund managers of all time and one of the greatest investors on Wall Street, he was one of the first activist shareholders and is credited with making that investment strategy mainstream for hedge funds.