William Koch, an energy magnate and the third brother of the conservative political activist billionaires Charles and David Koch, is suing California businessman Eric Greenberg, who sold him $300,000 worth of vintage wine in 2004 and 2005.
Experts have subsequently called the bottles a fraud and Koch has sued Greenberg over the sour deal, the New York Daily News reported.
Greenberg, who made a fortune in the dot-com era and amassed a wine collection topping 70,000 bottles, said he had no idea the bottles were fake when he sold them.
Koch's lawsuit, set to go before a federal jury in Manhattan District Court in New York next week, notes Greenberg tried auctioning the bottles previously but the auction house Sotheby's declined over concerns they could be fakes.
Greenberg's spokesman Bill Cunningham told the Daily News the size of his boss's wine collection virtually guarantees some of the bottles are fake.
"But to go from that and say, 'Because you have them you are guilty of fraud' is a big jump," Cunningham said.