Activist Paul Singer's Elliott Investment Management tried to force Bill Ackman's listed company to liquidate. : Elliott Investment Management targeted Pershing Square Holdings in 2017, when Paul Singer’s firm privately tried to force fellow activist Bill Ackman to liquidate his listed company. Ackman disclosed the details of the battle around the fund publicly for the first time during a three-hour interview on the Lex Fridman Podcast. The billionaire posted the discussion on X, the social media site formerly known as Twitter, on Tuesday.