William Ackman

William Albert Ackman (born May 11, 1966) is an American investor, hedge fund manager, and philanthropist. He is the founder and CEO of Pershing Square Capital Management, a hedge fund management company. Ackman is considered by some to be a contrarian investor but considers himself an activist investor.Research published at the University of Oxford characterizes Ackman's activities with Canadian Pacific Railway as paradigmatic of "engaged activism", which is longer-term in nature with correlated benefits to the real economy, as distinct from shorter-term "financial activism".Ackman's investing style has been praised and criticized by U.S. government officials, heads of other hedge funds, various retail investors, and the general public. His most notable market plays include shorting MBIA's bonds during the 2008 financial crisis, his proxy battle with Canadian Pacific Railway, and his stakes in the Target Corporation, Valeant Pharmaceuticals, and Chipotle Mexican Grill. From 2012 to 2018, Ackman held a US$1 billion short against the nutrition company Herbalife, a company he has claimed is a pyramid scheme designed as a multi-level marketing firm. His efforts were documented in the documentary film Betting on Zero.