August was a rotten month for stocks and it wasn't much kinder to some of the world's most successful hedge fund managers, early returns show.

Even some of the industry's titans, including Steven Cohen, Dan Loeb and David Einhorn, couldn't escape the global sell-off at the start of the month and finished August in the red.

Cohen's SAC Capital Advisors lost about 3 percent, Loeb's Third Point Offshore Fund fell 2.8 percent and Einhorn's Greenlight dipped 1.4 percent, people familiar with their returns said on Thursday.

While Cohen and Loeb remain in the black for the year -- SAC is up about 7 percent while Third Point is 3.9 percent higher -- many others haven't been so successful. Einhorn, who made headlines this summer with a now collapsed deal to buy a stake in the New York Mets baseball team, is off nearly 5 percent.

Whitney Tilson's T2 Partners LLC told investors that the fund declined 13.7 percent last month, leaving it off 22.1 percent for the year.

On the long side, our portfolio got clobbered across the board despite generally good company-specific news regarding our major holdings, Tilson said in a letter.

What hurt Tilson likely also led to more red ink at his college friend William Ackman's Pershing Square Capital Management. Ackman was already off double digits earlier in the month. So when Tilson said that losses in Citigroup, General Growth Properties, and J.C. Penney swamped his portfolio, they likely inflicted similar damage on Ackman, who also owned shares of the companies.

But the industry's most prominent loser is still John Paulson, the billionaire investor who misjudged the pace of economic recovery and was badly battered in financial stocks. His flagship Advantage Funds are still off between 25 percent and 35 percent for the year, one investor said.

For August, which began with a dramatic market sell-off and ended with tropical storm Irene drenching east coast hedge fund hubs in New York and Connecticut, hedge funds, on average, lost 5.85 percent, Hedge Fund Research data shows. That compares with 4.4 percent drop suffered by the Dow industrials, which made for the worst August in a decade, and the 5.61 percent drop registered by the S&P 500.

Hedge fund returns are often closely guarded secrets, so any information on how some of the top names are performing is closely monitored. Performance trackers like Hedge Fund Research are expected to release general statistics next week.

While the losers may be stealing the limelight, there are also some prominent winners who have generally positioned their portfolios for a drop in the markets.

The Renaissance Institutional Equities Fund, founded by mathematician turned hedge fund manager James Simons, returned to form earlier this year and gained 5.4 percent in August, leaving it up 25.6 percent for the year, an investor said. The Renaissance Institutional Futures Fund gained 6.6 percent in August and is up 9.16 percent for the year, the same person added.

Kenneth Griffin's Kensington/Wellington fund at Citadel also ended the month with gain, as it climbed 1 percent to be up 15 percent for the year, an investor said. Griffin's Global Equities fund gained 1.6 percent in August and is up 14 percent for the year.

(Editing by Steve Orlofsky)