Simpson Thacher & Bartlett is to advise longstanding client Kohlberg Kravis Roberts & Co (KKR) on the private equity powerhouse's public offering, reports The American Lawyer.

The transaction is a significant departure from KKR's original plans, announced a year ago, to raise $1.25bn (£627m) through an initial public offering. Instead, KKR will go public by taking over its Amsterdam-listed investment fund, KKR Private Equity Investors (PEI). After the transaction is completed, shares of KKR will be listed on the New York Stock Exchange. The proposed deal values KKR at a reported $12bn-$15bn (£6bn-£7.5bn).

Simpson Thacher regularly advises KKR on its biggest transactions, such as last year's $44.4bn (£22.3bn) acquisition, with TPG Capital, of the Texas utility TXU – at the time, the largest leveraged buy-out ever.

The relationship is so close that the lawyer who used to be KKR's key contact at Simpson Thacher, David Sorkin, went in-house in November as KKR's first general counsel. For the KKR PEI takeover, KKR is turning to Simpson Thacher partners Joseph Kaufman and Alan Klein.

KKR also brought in Linklaters, its longstanding fund counsel. New York partner Scott Bowie led the Linklaters team. KKR previously worked with Linklaters in 2006 when it launched KKR PEI on the Netherlands exchange.

For KKR PEI, KKR's European affiliate turned to French firm Bredin Prat as lead legal counsel for the affiliate and the independent directors. Bredin Prat partners Patrick Dziewolski and Benjamin Kanovitch led the team.

Cravath Swaine & Moore, which represented the underwriters when KKR PEI went public in May 2006, is acting as U. counsel to the independent directors of the general partner of the European fund. Partners George Stephanakis, Damien Zoubek, and Gregory Shaw advised on corporate matters. Michael Schler advised on tax issues.

Weil Gotshal & Manges is representing KKR PEI's financial advisers Citi and Lazard. The Weil Gotshal team is being led by New York corporate partners Michael Aiello and Thomas Roberts. Also involved is Paris corporate partner Claude Serra and London corporate partner Mike Francies.

De Brauw Blackstone Westbroek is acting as Dutch counsel for KKR PEI. Ogier partner Roger Le Tissier acted as counsel in Guernsey, Channel Islands, where the KKR PEI's general partner, KKR Guernsey GP, is based.

The The American Lawyer is a US sister title of Legal Week.

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