He has also amassed losses in an ongoing short battle over nutrition products group Herbalife. Pershing Square, which usually holds about 10 positions, has made billions investing in big winners such as General Growth Properties and Restaurant Brands International. It recently — and profitably — exited investments in railroad holding Canadian Pacific Railway and animal-health company Zoetis. The hedge fund has two new as-yet unidentified holdings. Mark Baak, director at Privium Fund Management, which has an investment in Pershing's listed fund, said that it was worthwhile to exit because Valeant "probably dominated all the conversations" with clients. "It's a better use of his time just to drop it," Baak said. Valeant may go down in history as a stock that tarnished the reputation of a number of prominent investors.