The ex-wife of one of America's richest men has sued the billionaire in New York for racketeering, saying he hid millions of dollars from her for decades.

Patricia Cohen's lawsuit was filed Wednesday in federal court in Manhattan against hedge fund operator Steven Cohen.

The lawsuit accuses Cohen of insider trading and says he had consistently and systematically defrauded her through repeated acts of mail and wire fraud. The couple separated in 1988 after nearly a decade of marriage.

The lawsuit noted Cohen was recently ranked by Forbes magazine as the 36th richest person in America, with a net worth of $6.4 billion.

Stanley Cohen spokesman Jonathan Gashalter said the lawsuit contained "ludicrous allegations made by a former spouse that are entirely without merit."

He also called the lawsuit "a transparent attempt to extort money."