"It was a PR failure," Ackman told Bloomberg News on Thursday, explaining that he had raised expectations about the presentation. "People were looking for the dead body and the smoking gun and instead what they got was a three-hour detailed regulatory presentation," he said in the interview.

"I'm my own worst enemy," Ackman said when asked whether he had been advised on how to present the data. Ackman was not available for comment but a spokesman confirmed his comments.

Herbalife's stock price climbed higher during the July 22 presentation, extending the fund manager's losses on his $1 billion short bet against the company that he unveiled 19 months ago when he first accused the company of running a pyramid scheme. Herbalife denies the allegations.

In spite of the Herbalife bet, Ackman's $14.7 billion Pershing Square Capital Management is delivering strong returns this year, having gained 25 percent in the first half of the year which ranks it as the industry's top performing hedge fund.

(Reporting by Svea Herbst-Bayliss)