Related Link: Citron Research Says It Will Not 'Dial Back Warnings' Regarding Valeant WSJ noted that Pershing Square's assets has fallen by about $4 billion in value since Valeant's stock peaked in August. Pershing Square's four funds have now lost 16 percent this year, after returning 40 percent last year. Ackman told Valeant that "management needs to come clean" and to hold a press conference immediately in order to "lay out everything you know." The company ultimately decided against holding a press conference, a move that irked Ackman who then phoned the company's lead director, Robert Ingram, and said "if Mike [Pearson] hides in the bunker on this, he can't be CEO." Ackman bought a 5.7 percent stake in Valeant, valued at around $3.8 billion, last March. At that time, the stake represented around 20 percent of Pershing Square's total portfolio.