(HuffingtonPost) - A federal jury in New York City sided with a Florida billionaire Thursday, finding that a California businessman defrauded him by selling bottles of phony vintage wine.

The jury in Manhattan returned its verdict and was then sent back to determine how much businessman Eric Greenberg owes William Koch, a yachtsman who won the America's Cup in 1992.Outside the courtroom, Koch was smiling and said he hoped the verdict sent a message to those in the wine auction market who follow a code of silence about fake wines.

He had sued Greenberg to seek the return of $320,000 he spent on 24 wines at a 2005 auction.

Greenberg – a former billionaire who built two Internet consulting companies before the 2000 collapse of those stocks reportedly reduced his net worth by as much as 90 percent – had insisted on the witness stand that he never intentionally sold a bad bottle of wine."I wouldn't sell a fake wine," he said as one of the trial's first witnesses. "I've never intentionally sold fake wine in my life."