Carl Icahn on Thursday put his money where his mouth is.
The billionaire investor said in a regulatory filing that he owns 14 million shares, or 13 percent, of weight-loss and vitamin company Herbalife Ltd. and signaled that he is ready to help put the company in play.
After weeks of speculation over exactly what the famed corporate raider might be doing, Icahn spoke up and put himself on a collision course with William Ackman, a rival activist investor who called Herbalife a house of cards and said he sees the share price going to zero.
The two men famously tussled on cable television in late January when Icahn called Ackman a "major loser" and warned him of trouble ahead in the form of a major short squeeze.
Herbalife's share price surged 20.6 percent in the wake of Icahn's filing, trading at $46.15 after the market closed.
Icahn said he wants to meet with Herbalife's management "regarding the business and strategic alternatives to enhance shareholder value, such as a recapitalization or a going-private transaction."
The company said: "We welcome all parties who see the same value in Herbalife that we do."
One short squeeze has already occurred, experts said.
(Reporting By Svea Herbst-Bayliss with additional reporting by Martinne Geller and Sam Forgione; Editing by Xavier Briand)