Lawyers for Raj Rajaratnam had argued on appeal that the government improperly persuaded a judge in 2008 to permit a wiretap to be placed on Rajaratnam's cellphone. The wiretap was used to record 2,200 private conversations by the founder of the Galleon group of 14 hedge funds.
The 2nd U.S. Circuit Court of Appeals said Monday that wiretaps were properly used.
Rajaratnam, arrested in 2009, is serving an 11-year prison sentence after the government said he made $75 million illegally. Prosecutors obtained more than two dozen convictions in a case they once called the biggest insider trading prosecution in history.
His lawyers declined to comment Monday.