Pershing Square Capital Management, L.P. is a New York-based hedge fund founded in 2004 by investor Bill Ackman. The firm is known for its activist investment strategy, where it takes significant positions in companies and seeks to influence management and corporate strategy to enhance shareholder value. Pershing Square has been involved in high-profile investments and activist campaigns, including companies like Herbalife, Chipotle, and Canadian Pacific Railway. Under Ackman’s leadership, the firm has gained a reputation for bold and sometimes controversial market moves, often making long-term bets on undervalued or underperforming businesses.