P2P services Morpheus, Grokster and Kazaa are due in court on 1 October following a judicial ruling that the defendants' motion for a summary judgment was premature.
Attorneys for the companies that run the services filed the summary judgment motion hoping to qualify for a "Betamax defence". This defence argues that the non-infringing uses of a technology should shield it from a copyright infringement suit, given that the technology has legitimate uses.
The Betamax defence originated in 1984, when the US Supreme Court ruled in Sony vs Universal City Studios that, although some uses of video recording technology infringe on copyright, that did not justify a ban on the technology.
While lawyers for the P2P defendants expressed disappointment that the judge delayed ruling on the motion, they indicated that they would press the Betamax defence during the jury trial.
Civil liberties group the Electronic Frontier Foundation (EFF) has pointed out that the software allows users to trade a variety of files, including shareware programs and public domain texts, not just copyright-protected works.
For the recording and motion picture industries, however, the widespread popularity of these services, which have only increased since the demise of the free-for-all version of Napster, represent a serious threat to business.