Billionaire Carl Icahn is extending a years-long proxy fight with co-billionaire Bill Ackman, upping his stake in Herbalife yet again.
The two have been battling over the legitimacy of the supplements and weight loss company since 2012, when Ackman called Herbalife a pyramid scheme and revealed a massive bet against it.
A regulatory filing this week shows that Icahn upped the stakes again, pushing his ownership from 20.8% up to 23.1%. He's the Los Angeles company's biggest stakeholder. At $54.70 per share, Icahn put an additional $100 million plus into Herbalife on Thursday.
Shares of Herbalife, which have more than doubled since Ackman's initial...