SCO has rejected claims from Victorian-based open source advocates that its call for commercial users to purchase Unixware licences could be a breach of Australian trade practices laws.

Open source lobby group Open Source Victoria (OSV) has asked the Australian Competition and Consumer Commission (ACCC) to investigate its claim that SCO's call breaches parts of the Trade Practices Act concerned with misleading and deceptive conduct.

SCO public affairs director Blake Stowell has rejected the claims.

The fracas over the license spun-off from a high-profile contractual and copyright dispute between SCO and global technology giant IBM.

SCO filed a US$1 billion lawsuit against IBM in March, alleging it illegally placed portions of code from its software, Unix System V, into the widely-used open source operating system Linux. The code was then made available -- falsely, claims SCO -- to Linux users under the legal aegis of the General Public License

SCO increased legal pressure on IBM in June. It terminated IBM's right to use or distribute a version of Unix it had developed for its AIX server software, and sought an injunction preventing it from using Unix System V.

SCO early this week registered copyrights over Unix System V in the U.S. and began manoeuvering to demand license fees from commercial users of Linux.

However, OSV spokesperson Con Zymaris argues SCO has already forfeited any copyright the company had over the code because it continued Internet-distribution of a version of the Linux kernel containing it under the GPL after its executives had laid their claim against IBM.

The GPL requires software developers that use open source code to jettison any claims to copyright over new products they develop from it in order to retain rights to distribute them.

"[SCO] can't just come back later and say we want to extract license fees...it's just not possible to do so," said Zymaris.

However, Stowell said other portions of the GPL support its right to protect its code. He says that SCO never gave IBM permission to place the code in Linux, rendering the terms of the license void.

However, SCO's Stowell said the company had pulled versions of the Linux kernel at the centre of the dispute from Internet distribution in recent weeks. According to Stowell SCO Chief Executive Officer, Darl McBride, requested the kernel be pulled offline in order to avoid creating perception the company was complicit with breach of its copyright.

Stowell's statement appears to be at odds with those of some Linux users. Open source enthusiasts who contacted ZDNet Australia claimed that SCO is still making the kernel available under the GPL and point to FTP sites within the caldera.com domain (www.caldera.com is an alternative host for SCO's Web-presence however, according to whois.com, the domain is currently available for renewal).

The ACCC said it will be seeking further information about the issue before it makes a statement on the matter.

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