"Mr. Icahn has never been accused of any wrongdoing and as he has said before, any suggestion he engaged in improper trading is inflammatory," the attorney for Icahn said.

Early in the insider trading investigation, federal authorities looked at what role, if any, Icahn may have had in sharing information with Walters about the consumer products company Clorox. Icahn was mounting a takeover bid for Clorox.

(Reporting By Jennifer Ablan; Editing by Bernard Orr)