The SCO Group has insisted that changes made by Silicon Graphics (SGI) to some of its Unix code will not be enough to prevent termination of SGI's Unix licence.

SCO plans to revoke SGI's Unix licence even though the latter claims to have removed all potentially offending code from its XFS journalling file system, now in Linux. But this does not go far enough, SCO has told vnunet.com.

The licence is due to be terminated on 14 October, two months after a warning letter was sent to SGI complaining that it had allowed code to be transferred from SCO's Unix System V into Linux.

The letter, dated 13 August, claimed that SGI subjected SCO's source code to "unrestricted disclosure, unauthorised transfer and disposition, and unauthorised use and copying".

In response SGI this week issued an open letter, signed by vice president of software Rich Altmaier, saying it had reviewed the XFS code and changed 200 lines out of more than a million supplied to Linux.

But the letter added: "Notably, it appears that most or all of the System V code fragments we found had previously been placed in the public domain, meaning it is very doubtful that the SCO Group has any proprietary claim to these code fragments in any case."

In response, SCO's director of public relations, Blake Stowell, told vnunet.com: "Making minor amendments to its XFS file system doesn't cure the breach. SGI must do more as outlined [in the August letter] to cure all of their breaches."

SCO has yet to decide how to enforce SGI's licence termination, but Stowell hinted that the company may remove all SGI's rights under its contract.

"We don't believe that SGI has taken all of the steps necessary to cure all of the breaches, and in fact in our letter to them, we state 'SGI's breaches of these agreements cannot be cured'.

"Nonetheless, we will provide SGI with two months to remedy all violations of these agreements."

SCO is currently suing IBM for $3bn, claiming the company misappropriated its Unix code by allowing it to be used in Linux. It terminated IBM's System V licence in June.

It has since told Linux customers they must buy a Unix System V licence from SCO.

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