Greenlight adds to Green Mountain short, likes new iPhone

David Einhorn, president and co-founder of Greenlight Capital
Scott Eelis | Bloomberg | Getty Images

Greenlight Capital, David Einhorn's hedge fund firm, gained 4.3 percent in the third quarter and is now up 11.8 percent for the year, according to an investor letter obtained by CNBC.

The equity-focused firm said virtually all its long investments were profitable during the quarter, including large gains from positions in Apple and Vodafone.

Greenlight remains bullish on Apple, especially with the launch of the iPhone 5s.

"We believe that near-term share performance will track the success of the new phones, while the longer-term share price will reflect the market's eventual understanding of AAPL's strong ability to earn high-margin and recurring revenue streams," the letter said.