William A. Ackman is founder, CEO and portfolio managerof Pershing Square Capital Management, an investment advisory firm, or hedge fund, that he founded in 2003 and typically focuses on large-cap and mid-cap companies.
Most recently, Ackman waged a successful proxy battle to get a new CEO at Canadian Pacific.
Prior to forming Pershing, Ackman co-founded Gotham Partners Management Co., an investment adviser that managed public and private equity hedge-fund portfolios. Ackman began his career in real estate investment banking at Ackman Brothers & Singer.