Hedge-fund manager Bill Ackman is short the nutritional-supplement seller Herbalife, according to someone familiar with the matter, and has told people he considers the business to be little more than a "pyramid scheme."
Ackman, founder of the $11 billion hedge-fund company Pershing Square Capital Management, put on the bearish Herbalife position about seven or eight months ago, according to the person familiar with the matter, and has spent about a year researching the company.
The fund manager has told people that Herbalife—best known for its weight-loss shakes—is the most compelling short case for a stock he has "ever seen," this person added. A "short" is a bet that a stock's price will decline.