Former Goldman Sachs Group Inc Director Rajat Gupta suffered a tough blow in long-running insider trading case on Tuesday after a U. S. federal appeals court upheld his conviction and two-year prison term for securities fraud & conspiracy.

The 2nd U. S. Circuit Court of Appeals turned down Gupta's claim that the court should not have admitted wiretap evidence to determine that he had leaked information about Goldman's finances via phone to Galleon hedge fund founder Raj Rajaratnam.

Circuit Judge Amalya Kearse said that Gupta's calls that took place merely one minute after he learned 'extraordinary' information about Goldman's finances were powerful evidence that Gupta had provided Rajaratnam with confidential information.

Expressing disappointment on the ruling, Gupta's lawyer Seth Waxman said, "We're very disappointed in today's decision, believe Mr. Gupta is entitled to a new trial, and are closely reviewing the opinion with an eye toward further review."

Sixty-five-year-old Gupta, a former global MD of consulting firm McKinsey & Co, is the top corporate official convicted in the long-running probe into insider trading.

The U. S. government has so far won seventy-nine convictions and guilty pleas in its insider trading probe that was launched in October 2009. The federal appeals court's most recent ruling against Gupta is a fresh endorsement of the forceful tactics that government prosecutors have used to stop insider trading.