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David Einhorn
Amid a bull market in equities, billionaire hedge fund manager David Einhorn has performed poorly and admits it's been "far worse" than he could have imagined.
His hedge fund firm, Greenlight Capital, lost 5.4 percent in the second quarter, bringing the performance of its funds to a year-to-date loss of 18.3 percent, according to a letter obtained by CNBC. The S&P 500 has gained 2.6 percent this year.
