Unix dispute aired by Novell and SCO

SCO Group and Novell have begun publicly airing documents related to their dispute over Unix copyrights - important factors in SCO's claim to intellectual property rights for the Linux operating system.

SCO's and Novell's documents offer details of the 1995 deal under which Novell sold its Unix business to SCO's predecessor.

The documents also are the basis for SCO's current claims to Linux and Novell's belief that it can protect its customers from SCO's legal demands.

Lindon, Utah-based SCO is fighting with corporate users of Linux - and the software industry at large - and has engaged in a high-profile legal battle with IBM, all in an effort to establish its claim to fees for use of the open source operating system.

SCO believes that Unix software was illegally moved into Linux and is demanding that companies that use Linux pay it licence fees. Provo, Utah-based Novell is challenging the move by arguing it retains key Unix copyrights and offering legal protection for customers who buy its products, called SuSE Linux.

Both companies' websites now offer interested parties the opportunity to scrutinise the Asset Purchase Agreement from 1995, a crucial amendment to that contract.

SCO also released press materials issued when the company purchased its Unix assets from Novell. SCO asserts that the press release confirms that the company purchased the Unix intellectual property along with the Unix business and source code, among other things.

Novell released several recent letters to and from SCO regarding the auditing of SCO's use of Unix; Novell's assertion that IBM is permitted to release its enhancements to Unix as open source software as long as it doesn't release the original Unix source code; and Novell's efforts to nullify SCO's move to cancel the Unix contracts of IBM and Silicon Graphics.

SCO believes that the Asset Purchase Agreement provided Novell with a Unix licence but under the condition that Novell use the licensed technology only for internal purposes or for resale in bundled and integrated products sold by Novell that do not directly compete with Unix products marketed by SCO. SCO further maintains that a Novell Linux offering violates that part of the agreement.

However, in late December, Novell, which bought Unix from AT&T before selling at least some of the intellectual property to a SCO predecessor, disputed SCO's claims of Unix copyright ownership.

Novell said the US Copyright Office gave it copyright registrations for 11 versions of System V Unix. Legal action between the two companies is expected as a result of those claims.

Matt Hines and Stephen Shankland write for CNET News.com.