The latest and final draft of the forthcoming General Public License, version 3, states that companies that distribute open-source software cannot extend patent protection to some users of the software and not others, regardless of how or from whom the user received it.
Microsoft claims that Linux and other open-source software programs violate 235 of its patents. In November, the company struck an alliance with Novell under which Microsoft agreed not to sue Novell's Linux customers. Microsoft gained the right to resell Novell's SuSE Linux products and services at a markup.
The latter fact makes Microsoft a Linux distributor for the purposes of GPLv3, according to the Free Software Foundation. The FSF controls the licensing process around open-source software.
Under new terms inserted into the final draft of GPLv3, "If you arrange to provide patent protection to some of the people who get the software from you, that protection is automatically extended to everyone who receives the software, no matter how they get it," according to an explanation of the rules posted on the FSF Web site.
"This means that the patent protection Microsoft has extended to Novell's customers would be extended to everyone who uses any software Novell distributes under GPLv3," the FSF continued.
FSF makes no bones about the motivation behind the new language. The provision is a means "to attack the Microsoft-Novell deal," the group stated.
The new rules are included in what the FSF is calling a "last call" draft of GPLv3. The organization said it expects the document to be finalized within 30 days.
If GPLv3 takes effect in its current form, it could force Microsoft to either terminate its alliance with Novell or give up its patent claims over parts of Linux. In Microsoft's favor, however, is the fact that Linux inventor Linus Torvalds has previously said that he intends to maintain the Linux kernel under GPLv2, which doesn't forbid arrangements like the Microsoft-Novell alliance.
Still, it could prove impractical for Microsoft and Novell to distribute only those parts of Linux not covered by GPLv3.
Last week, Novell warned in a regulatory filing that changes to the open-source license contemplated by GPLv3 could undermine its relationship with Microsoft.
Microsoft officials on Thursday slammed the Free Software Foundation over the draft. "It is unfortunate that instead of encouraging industry collaboration to solve problems for customers, going forward the FSF wants to burn down this bridge," said Horacio Gutierrez, Microsoft's VP for intellectual property and licensing, in an e-mail.