Steve Jobs with iPod
Video testimony by Steve Jobs recorded before his death was used in iTunes antitrust trialReuters

All plaintiffs in a billion-dollar class-action lawsuit brought against Apple on behalf of eight million iPod owners have been dismissed by the judge - but the trial will continue if lawyers can find a replacement.

In an unusual move, US District Judge Yvonne Gonzalez Rogers said the trial will continue if a replacement plaintiff can be found by the time proceedings open on 9 December.

The final plaintiff was kicked out of court after it emerged she did not own an iPod claimed to be affected by the lawsuit.

The latest twist in a trial which could cost Apple $1 billion (£637 million, €809m) comes after the late Apple co-founder Steve Jobs gave evidence via a video recorded months before his death in October 2011.

The Associated Press reports the judge said she was "troubled" by the legal team's failings, and scolded plaintiff Marianna Rosen after Apple lawyers successfully proved that, although two iPods she owned were included in those alleged to be affected, they were purchased with a credit card belonging to her husband's business, and thus she was not the legal owner.

The case must go on

Despite this, the judge said she had an obligation to the "millions of absent class members" to let the case continue, so long as another lead plaintiff can be found.

Lawyers acting on behalf of the iPod owners are seeking as much as $350m (£224m, €282m) in compensation from Apple, which is accused of "locking customers" into its products and services. However, should the plaintiffs win and Apple be found guilty of violating federal antitrust laws, this sum would be automatically tripled.

Started by three people in January 2005, the lawsuit accuses Apple of violating US antitrust law by preventing music purchased on iTunes from being played on devices other than iPods, and by not allowing music purchased on other services to be played on iPods.

But because Apple removed digital rights management (DRM) from iTunes in early 2009, the lawsuit only covers iPods purchased between September 2006 and March 2009. In all, 29 different models of iPod are included in the lawsuit.

Although some eight million people are being represented in the case, US law deems that there must be at least one named plaintiff who suffered the losses or injuries alleged in the case. Plaintiff's attorney Bonny Sweeney said her office had heard from a number of volunteers to take the role of lead plaintiff, and that they will "stand ready and willing" to take part in the trial later today.

Rossen put forward several iPods in her defence, but Apple lawyers dismissed them for either having the wrong software, or for being purchased outside of the time frame recognised by the case; her final two iPods were then dismissed because she was not their legal owner.