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Kohlberg Kravis Roberts
Kohlberg Kravis Roberts
The British pharmacy chain was one of KKRs old-school LBOs.
2008 Rank: 3
2007 Rank: 2
Recent buyout fundraising: $27.3 billion

In July 2007, the firm announced it was preparing to go public. KKR then delayed its proposed IPO (finally going public through a takeover of its Amsterdam-listed affiliate investment fund in July 2008), canceled deals like the one for Harman International Industries, and granted concessions to lenders on others, including First Data.

It did, however, manage to complete $120 billion worth of massive, old-school LBOs, including British pharmacy chain Alliance Boots, energy utility TXU, and discounter Dollar General.

Headwind issue: KKR's efforts to diversify remain a mixed bag. Publicly traded KKR Financial, which invested in U .S. housing loans, and KKR Private Equity Investors, an Amsterdam-listed co-investment fund, both got clobbered by the credit crunch.

Worth noting: KKR's suite of offices in Manhattan is known for its 19th-century paintings, like Renoirs and Monets, often borrowed from Henry Kravis's personal collection. But when the firm added a second floor last year, it chose more contemporary art to reflect high hopes about future returns. (This article was updated July 28, 2008)

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Last updated July 28 2008: 4:28 PM ET
Source: Rankings are based on a firm's most recently raised buyout fund(s). Fortune looked at data from Capital IQ, institutional investors, and the companies themselves to determine the size of the most recently raised buyout funds. For some firms that means a fund that was raised in 2007; for others it might be 2006. Whatever the date, the most recent fund was the one we counted. In the case of companies that raise multiple funds simultaneously as opposed to raising a single fund at a time, we chose to count only those private equity funds that were not raised in public markets and that were earmarked for buyouts (as opposed to investments in debt, venture capital, or other ventures).
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