David Bonderman, TPG

MGM, Burger King, J. Crew
In January, it was reported that TPG had $25 billion to invest in 2009 buyouts. But Bonderman's shop has made some bad bets-most notably, the ill-timed investment in now-defunct Washington Mutual.

Leon Black, Apollo
AMC Entertainment, Linens 'n Things, Sotheby's, International Realty

Although Apollo announced in January that it plans to raise $500 million for a metal-trading hedge fund, some of its major investments, like Harrah's (which it co-owns with TPG), are struggling, while others, including Linens 'n Things, have already gone under. The prospects for its initial public offering are now unknown.

Stephen Schwarzman, Blackstone
Weather Channel, Hilton Hotels, Universal Studios Parks

In December, Blackstone announced it would be closing two of its hedge funds due to lack of investment and laying off 70 employees.

Henry Kravis, Kohlberg Kravis Roberts
Dollar General, Nielsen, Toys R Us

Kravis' funds tumbled 84 percent in 2008. The New York Stock Exchange recently threatened debt-investment KKR affiliate KKR Financial Holdings with delisting after its value dropped 90 percent in 2008 and it failed to meet listing standards.

David Rubenstein, Carlyle Group
Dunkin' Donuts, AMC Entertainment, Hertz

Carlyle raised $13.7 million, just short of its $15 million target, for a new fund in 2008, even as the markets were tanking. But the Washington powerhouse is not immune to bad times; in mid-December, Carlyle announced plans to cut 100 jobs, or 10 percent of its payroll.

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