Former Goldman Sachs director Rajat Gupta "threw away his duties" when he passed confidential company information to hedge fund founder Raj Rajaratnam, a prosecutor told a US court, even as defence argued that the Indian American was not an insider trader and "does not belong in this courtroom".

The trial of Gupta, one of the most high profile Wall Street executives to be charged with insider trading, began in US District Court, Southern District of New York yesterday amid intense media glare.

In his opening remarks to the 12-member jury, Assistant US Attorney Reed Brodsky said Gupta "threw away his duties and responsibilities and broke the law," by sharing insider tips with Rajaratnam, who is currently serving an 11 year prison sentence on insider trading charges.

The case of illegal insider trading "is about this man," Brodsky said facing the jury and pointing his hand toward Gupta "and how he violated his duties and abused his position as a corporate insider".