That’s why his hedge fund Pershing Square, which manages roughly $35 billion in assets, offers its four dozen employees generous workplace benefits, including broad ownership and an even rare degree of flexibility for Wall Street. That year, he founded Gotham Partners with fellow Harvard graduate David P. Berkowitz, but the investment firm later failed in part after its bets on private companies backfired. In 2004, he launched Pershing Square Capital Management, the activist hedge fund that has grown into one of Wall Street’s best-known investment firms. Since its founding, Pershing has built major stakes in companies including Chipotle, Universal Music Group, and J.C. Penney. For Ackman, that’s one of AI’s biggest promises: making world-class expertise available to anyone with an internet connection.