William Ackman's Pershing Square is largely flat for the year after a bruising August in which the hedge fund lost 3.6 percent, said two investor sources who are not permitted to discuss the private fund's numbers publicly.
The sharp decline was largely driven by big bets on J.C. Penney and Herbalife and have left Pershing Square, with $10.73 billion in assets, badly trailing the broader hedge fund industry and the overall stock markets.
Pershing Square's poor performance stands in sharp contrast with the benchmark Standard & Poor's 500 Index, which was up 14.5 percent for the year as of Aug. 31.
Coming on the heels of a 2.2 percent loss in July, the fund's latest numbers revived worries among investors ranging from pension funds to wealthy individuals about how the manager, a longtime industry darling, can repair the portfolio.
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The year-to-date washout, after a 6.2 percent gain in the first quarter, shows just how badly Ackman is lagging behind many rival managers who have posted double digit returns this year.
While August was tough for many hedge fund managers, Daniel Loeb's Partners Fund is still up 15.6 percent for the year despite a 0.7 percent drop last month, a third source said. And David Einhorn's Greenlight Capital rose 1 percent in August month and is up 11.4 percent for the year, the person added.
The source is familiar with the funds' numbers but is not permitted to discuss their performance publicly because they are private.