The other billionaires, who invested separately from Blavatnik, are Leon Black, Joshua Harris and Marc Rowan--cofounders of New York private equity firm Apollo Global Management.

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Joining the aforementioned group of U.S. deals in the global top 10 were BankUnited and private equity firm Apollo Global Management, run by billionaires Leon Black, Marc Rowan and Joshua Harris.

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For billionaires Leon Black, Joshua Harris and Marc Rowan, co-founders of Apollo Global Management LyondellBasell and other chemical investments that looked like a disaster not so long ago are now helping motor the legendary private equity firm to its own IPO.

FORBES: How Billionaires Lost And Made Fortunes In LyondellBasell