Hedge-fund manager William Ackman

Hedge-fund manager William Ackman

Scott Eells/Bloomberg

William Ackman, founder and chief executive officer of Pershing Square Capital Management LP, is seen in this Dec. 20, 2012 photo. He said he had turned over more than a year’s worth of research to the U.S. Federal Trade Commission in support of his contention that Herbalife is a pyramid scheme.