Mr Quattrone made his name during the technology boom

A US appeals court delivered the ruling on Tuesday, just nine days before Mr Quattrone was due to report to prison.

A spokesman for Mr Quattrone welcomed the decision.

"We remain very confident that the conviction will be reversed, and that Frank Quattrone will not have to serve a day in jail," he said.

Mr Quattrone was found guilty earlier this year of hindering an investigation into whether his bank, CSFB, had given some clients privileged access to 'hot' new technology stocks.

White collar

The case centred on an e-mail he forwarded to colleagues advising them to "clean up" their files.

The e-mail was sent in December 2000, after regulators had launched an inquiry into allegations that some banks, including CSFB, regularly gave clients shares in newly-floated tech stocks in return for continued investment banking business.

Mr Quattrone has said he was simply instructing CSFB staff to follow the bank's policy of routinely purging outdated documents, and did not intend to obstruct the investigation.

Mr Quattrone was one of the first Wall Street bankers to recognise the stock market potential of internet and technology firms.

During the 1990s, he worked on the stock market flotations of illustrious tech sector firms such as Netscape, and Cisco Systems, and is reported to have once earned $120m (�66m) in a single year.

He is one of several high-profile business figures to have received prison sentences as part of a recent crackdown on white collar crime.