It is claimed that the the terms are incompatible with the General Public Licence (GPL), the licence that governs the Linux operating system.
"The agreement is going to run foul of the GPL," Mark Webbink, a director with the Software Freedom Law Center said. The group offers legal support to open source developers and users.
Full details of the agreement have yet to be published, but Webbink bases his assertions on information that has been released so far.
Siding with Webbink, Red Hat's general counsel Michael Cunningham said in an emailed statement that the firm has "concerns that the patent arrangements may have not been made compatible with open source licensing".
A spokesperson for the European Union did not immediately return a request for comment.
Microsoft on Monday agreed to end its appeal against a 2004 European Commission ruling that seeks to ensure fair competition in the software market. The ruling mandates that Microsoft provides third party software developers with the interoperability information required to create products that work well with Microsoft software.
Microsoft will offer non-public interoperability information at a €10,000 flat fee. Commercial vendors can purchase a licence for Microsoft's patents on the interoperability information at a royalty fee of 0.4 percent of revenues, while non-commercial open source projects will receive a royalty free patent pledge.
The EU stressed that the agreement would open up the interoperability information to open source developers. "I have always said that open source software developers must be able to take advantage of [the 2004 ruling]: now they can," the Commission's competition commissioner Neelie Kroes boasted in a press release.
The patent licensing offer however is worthless to commercial Linux vendors, claims a source who is familiar with the terms of the agreement who spoke on the condition of anonymity. The licence only covers the distributor who purchased the licence (Red Hat for instance) and its customers.
The Microsoft licence doesn't cover recipients further downstream – for instance if a Red Hat customer gives a copy of the software to a partner. Because Microsoft is limiting the licence to the vendor and its first customer, it runs foul with the GPL.
The open source licence explicitly prohibits such discriminatory licensing. The open source licence therefore renders the EU mandated patent licensing useless to GPL vendors, argued Webbink.
The overall agreement does however have some value to open source vendors.
"It will take some degree of effort, but one should not assume that they will simply have to take the patent licence," said Webbink.
"This is the best solution within the constraints that the Commission has to live with. It's not a perfect solution, but it's a solution that open source could potentially work with. It will take some further work."
Microsoft's patents are estimated to cover only 25 to 30 percent of the interoperability information. A company could purchase the non-public interoperability information and use it to build software that stays clear of areas that are covered by Microsoft's patents.
Webbink also suggested that the Open Innovation Network (OIN) could build a patent portfolio to cover Microsoft interoperability. The company collects patents that cover key open source applications and uses those to defend the software from patent threats. If Microsoft would file a patent claims against an open source vendor in the interoperability space, OIN could use its patents to lodge a counterclaim.
Some of Microsoft's patents will prove to be unenforceable. Or developers could work around the patent by architecting their software in such a way that the Microsoft patents don't apply.
Microsoft's EU patent pledge incompatible with GPL
By Tom Sanders on Oct 25, 2007 7:40AM
Linux vendors will be unable to license Microsoft's interoperability patents under the terms that were mandated by the European Commission, open source legal experts argue.
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