A Linux evangelist reckons that Microsoft 's deal with Novell weakens its patent claim against Linux. Eben Moglen was quoted as saying the software giant's patent claims were "to disrupt free software production through the inculcation of a large inventory of most-likely invalid patents." Moglen represents the Free Software Foundation (FSF).

Last week Microsoft claimed that Linux and many other open source applications violate the best part of 250 (count 'em) of its patents. Moglen alleges that the FSF has tripped up Microsoft with the latest version of the GPL, or General Public License, under which most open-source programs are distributed.

Novell has already paid for so-called 'vouchers' which indemnify it from any action as part of its deal with Microsoft, but which, says Moglen, make Microsoft a Linux distributor. But they aren't dated, so they can be used at any time.

And the new version 3 of the General Public License - due to come in later this year - means that everybody else will be indemnified from any claim, too. "Our goal," says Moglen, "is to add one more layer of probable defense against the Microsoft patent aggression, which Microsoft has just been busy thumping its tub about this week".

According to the Fortune article which broke the original story, Microsoft doesn't believe its distribution of Novell coupons would make it subject to the GPL in any way. So even if Microsoft were to press through its claims, when GPL v3 comes in it will be legally shown to have licensed its patents, he says.

"So...Novell will be protected for the long haul, and Microsoft will be endangered for the long haul by GPL 3, and that's as it should be.

"Once that has happened, patent defenses will, under the license, have moved out into the broad community and be available to anybody who Microsoft should ever sue for infringement," says Moglen.