Herbalife Ltd.'s shares fell sharply for the second day following the hedge fund manager William Ackman's critical presentation on the nutritional supplements company.
Ackman, founder and CEO of Pershing Square Capital Management L.P., said Wednesday that he has been shorting the company's stock for several months and that he thinks Herbalife is a pyramid scheme. Short sellers earn money when a stock declines.
The hedge fund manager reconfirmed this in a presentation at the Sohn Conference Foundation meeting on Thursday.
Ackman told CNBC that he expects the Federal Trade Commission will take a "hard look" at the company, which signs up independent distributors to sell supplements, weight loss products and other items in more than 80 countries.
Herbalife Chairman and CEO Michael Johnson said Wednesday that the allegation that Herbalife is a pyramid scheme is "bogus".
Johnson said the company found that a large number of puts options on its stock are due to expire this Friday and suggested that the timing of the presentation is suspect. A put option is the opportunity to sell a certain number of shares at a certain price and date in exchange for an upfront fee. Ackman denied on CNBC that he has any put options on the stock. He also said he intends to donate his profits from his position on the company to charity.
Herbalife said it asked Ackman to allow Herbalife participate in his presentation but Ackman declined.
"Now we know why," the company said in a statement Thursday. "Had our executives been there, they would have been able to tear Mr. Ackman's premises and interpretation of our business model apart. His misstatements and mistakes are too numerous to address immediately."
The company, which operates out of Los Angeles, is urging the Securities and Exchange Commission to investigate the events. It said that this appears to be "yet another attempt to illegally manipulate the market by overzealous short-sellers."
Shares fell nearly 9 percent to $34.04 in afternoon trading Thursday. This follows a 12 percent drop Wednesday when news of the short position and other claims were disclosed.