The lawsuit, announced today, was filed in a US District Court in Nevada. It claims:
"AutoZone violated SCO's UNIX copyrights by running versions of the Linux operating system that contain code, structure, sequence and/or organization from SCO's proprietary UNIX System V code in violation of SCO's copyrights."
SCO requests "injunctive relief against AutoZone's further use or copying of any part of SCO's copyrighted materials and also requests damages as a result of AutoZone's infringement in an amount to be proven at trial."
The case is just the latest development in a dispute that began in March last year when SCO filed suit against IBM, accusing Big Blue of letting parts of UNIX 'slip' into Linux, in breach of SCO's rights.
It originally sued IBM for $1 billion, then increased the claim to $3 billion, and last week gained approval for the claim to be increased to $5 billion.
The case represents the biggest clash between open source and proprietary software groups since open source software began to be recognised as a credible business alternative to proprietary products.
Developments over the past year include a counter suit by IBM against SCO, the filing of a suit against SCO by Linux distributor Red Hat, and actions between Novell and SCO over who actually owns the intellectual property rights in the UNIX system.
In addition to this SCO has registered copyrights in critical UNIX source code (in the US, unlike the UK, there is a system of copyright registration), and in July 2003 it announced that it would begin contacting companies about their use of Linux and offer them the chance to purchase a UnixWare license – or risk facing an infringement suit.
SCO followed this up in December by sending written notices to its existing UNIX licensees – 6,000 in all – requesting confirmation that they are not in breach of their licence agreements, and have not used the UNIX code in Linux.
To date only one company has admitted purchasing a UnixWare licence: server provider EV1Servers.Net, earlier this week. According to SCO, the license will allow "EV1Servers.Net and its customers to continue running business operations on Linux servers without interruption or concern regarding SCO IP issues."
The announcement of the lawsuit against AutoZone, a Fortune 500 company, came the same day as the publication of a survey by Evans Data Corporation, suggesting that more than 90% of Linux developers believe that SCO's claims over Linux have no merit.
Nearly 60% of respondents to the Evans Data report have evaluated the intellectual property risks of Linux in their companies, but only 13% indicated the lawsuit would either "absolutely" or "probably" impact their company's adoption of Linux.
UPDATE:
Shortly after this story was written, SCO announced that it had filed a similar lawsuit against DaimlerChrysler Corp., suing the car giant in Detroit's Oakland County Circuit Court.