According to an SEC filing, Icahn bought 322,716 more shares of
Herbalife has been a battleground for hedge fund managers since last December, when Bill Ackman announced that he was shorting the stock and would donate the profits of his short to charity.
Ackman claims that Herbalife, a nutrition firm with a multi-level marketing business model, is actually a pyramid scheme.
Earlier this year, Icahn jumped on the other side of Ackman's trade.