Green Mountain roasts Einhorn's Greenlight

Green Mountain Coffee Roasters Inc. single-serve coffee capsules
Scott Eells | Bloomberg | Getty Images

Green Mountain Coffee Roasters' stock surge likely has a big victim: David Einhorn's Greenlight Capital.

Einhorn told attendees of his annual investor event on Jan. 21 at the American Museum of Natural History in Manhattan that Greenlight still had a short position in the coffee company.

Green Mountain, long a favorite for hedge funds to bet against, got a major boost Wednesday when Coca-Cola announced that it would purchase a 10 percent minority stake in the company as part of a $1.25 billion deal.

Shares were trading around $80 late Wednesday. But the stock opened up more than 30 percent on Thursday at $108.