Napster was granted a slight reprieve on Monday, albeit in the form of an another injunction from US District Judge Marilyn Hall Patel.

Patel issued an injunction essentially ordering Napster to continue with the blocking mechanism it put into place on its file-sharing service on Sunday night.

The injunction puts the burden of notification on the recording industry, which must provide four things to Napster for songs to be blocked: the title of the work to be blocked, the name of the artist, one or more filenames used to identify the song on Napster, and copyright certification.

Under the injunction, Napster will have three business days to "prevent such files (identified by the plaintiffs) from being included in the Napster index", in which case Napster would then use its 'screen' to prevent other users seeing the specific file in any database, thereby making it impossible to download.

One analyst was surprised that the judge appears to be letting Napster's blocking software serve as the main source of blocking titles. "I certainly don't think the blocking has been very effective so far. People are already getting around it," Malcolm Maclachlan, electronic media analyst with research firm IDC, said.

IDC is part of the IDG group, as is PC Advisor.