The divide between billionaire investors Carl Icahn and William Ackman is getting deeper.
A regulatory filing Thursday shows that Icahn holds a 12.98 percent stake in nutritional supplement distributor Herbalife Inc. and intends to have discussions with its management on business and strategic alternatives to enhance shareholder value, including the possibility of going private.
Herbalife has become part a long-running feud between the two activist investors that led to a shouting match on live television last month. The two Wall Street titans traded barbs on CNBC about an old investment deal that ultimately led to a fight over Ackman's position on Herbalife.
Hedge fund manager Ackman said in December that he believes Herbalife is pyramid scheme and he took a short position in the stock. Short-sellers make money when the stock they're betting against declines.
Icahn has said publicly that it was no secret that he neither liked nor respected Ackman and didn't like how he had approached his short position in Herbalife, which he said was "getting a room full of people to bad mouth the company."
He has previously refused to comment on whether he held a position in Herbalife, but many speculated that Icahn bought a stake in a move against his old adversary. He joins another investor, Dan Loeb of Third Point LLC, who previously disclosed an 8.2 percent stake in Herbalife.