Hedge fund manager Bill Ackman just disclosed a position in Uber. Bill Ackman is one of the most closely followed investment personalities on Wall Street. As CEO of hedge fund Pershing Square Capital Management, Ackman has been at the center of some creatively structured investments in recent history.

Go big or go home. Billionaire investor Bill Ackman of Pershing Square Capital Management takes that sentiment to heart. His hedge fund has some $13 billion in assets under management, but he owns just 10 stocks (track his portfolio here),