A US court has ruled that song-swapping site Napster can resume operations.

The decision overturns a ruling last week ordering Napster to remain offline until it complied with an injunction to remove all copyrighted music.

But it is unclear whether Napster will ever resume its free song-swapping service because it is preparing to launch a paid subscription service later this year.

Napster spokeswoman Ricki Seidman said: "We have no immediate comment on when we are going to start."

Court wrangles

Napster, sued by the recording industry in 1999 for copyright infringement, went offline on 2 July to install new software that would keep copyrighted material off the company's site.

On 11 July, District Court Judge Marilyn Hall Patel ordered the site to stay offline after the company said it could not guarantee that 100% of the copyrighted songs on the network could be removed.

Napster immediately appealed and in a short one-page order on Wednesday, the appeals court ruled that Judge Patel's order was stayed "pending a further order of this court".

It is not the first time the appeals court has reversed Judge Patel's orders in this case.

Industry 'confident'

In February, the court modified Judge Patel's order demanding Napster remove all protected works from its site.

It said Napster must remove the works, but only after the recording industry notified Napster which files on Napster's servers contained copyrighted songs.

Napster reminded the appeals court of that earlier ruling when it asked the appeals court to lift Judge Patel's most recent order.

The Recording Industry Association of America (RIAA) noted that the court only temporarily lifted Judge Patel's order and will hear arguments on the case later this year. The industry said it expected to win then.

An RIAA attorney said: "We are confident that after a thorough review the 9th Circuit Court of Appeals will uphold Judge Patel's decision."

He added that the appeal court decision still required Napster to remove copyrighted works that both it and Judge Patel had found were violating copyright laws.

"It is important to note that the ruling does not change in any way the fact that Napster must prevent copyrighted works from appearing on its system as previously ordered by the court."