The court said the access ban must be lifted because a law normally invoked to obtain the seizure of criminal assets had been transformed into "an atypical prohibitory order" obliging the ISPs to refrain from providing their services.

Simona Lavagnini, a lawyer representing the interests of the Italian music industry, said she was confident the Court of Cassation would uphold the validity of the ISP ban. "This instrument has already been used to combat child pornography and phishing. If it wasn't possible to use it in this case in relation to foreign Web sites, it would mean there is a gap in our legislation," Lavagnini said in a telephone interview.

Lavagnini said there was no prospect of The Pirate Bay founders ever being extradited from Sweden to serve a term in an Italian jail, but there were better chances of a possible fine being levied and of assets being seized to compensate the plaintiffs in the case for damages.

The Pirate Bay's founders have shown no sign yet of having been deterred by the Swedish verdict. Sunde sent a Twitter message after his conviction saying: "Stay calm -- nothing will happen to TPB, us personally or filesharing whatsoever. This is just a theater for the media."

Sunde's Italian lawyer, Giovanni Battista Gallus, also professed optimism about the likely outcome of an eventual Italian trial. "I continue to maintain that no punishable activity has taken place in Italy. We can't allow the criminalization of an instrument such as torrent tracking, which can be employed for perfectly legal uses," Gallus said in a telephone interview.

The response to torrent trackers was similar to the initial official reaction to the introduction of video-recording machines, which can be used for both legal and illegal activities, Gallus said.

Sunde had not been notified that he was under investigation by the Italian authorities and had only found out about it because it had been widely reported in the media, Gallus said. "He was amazed to discover that he was subject to criminal proceedings in Italy, a country that he has never visited and where no servers associated with The Pirate Bay are located."

Gallus said the Italian court would have to consider how the European Union's directive on e-commerce applied to operators who mediated between third parties but did not make any copyright material directly available themselves.