Microsoft vouchers undercut patent claims

Novell's deal with Microsoft (on behalf of its customers, of course) could end up benefiting everyone in the open source community after all, thanks to a missing expiration date and a nifty little clause in GPLv3.

Microsoft announced last week that it holds exactly 235 patents which are infringed by Linux source code. It wasn't letting out much in the way of specifics, but the announcement prompted speculation that the software firm was about to start enforcing these patents, or using the threat of enforcement to bring OS distributors to heel as it did with Novell.

But thanks to the deal it did last year with Novell, these plans may now come to naught.

Free Software Foundation lawyer Eben Moglen points out that the "vouchers" Novell bought to indemnify its customers have no expiration date. This is fine and dandy, except that Microsoft becomes subject to GPLv3 as soon as the new license comes into effect. Then the indemnity Microsoft was so keen to extend to Novell's customers is extended to everyone else as well.

This is why:

GPLv3 says: "If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license providing freedom to use, propagate, modify or convey a specific copy of the covered work to any of the parties receiving the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it."

Moglen and other open sourcerers argue that this means as soon as someone buys SUSE after GPLv3 comes into effect, there is a reasonable defence for anyone Microsoft chooses to pursue for patent infringement.

According to various net reports, including Groklaw and Seattle PI blogger Todd Bishop, Mogeln said: "If you make deals with a party having patents, to pay tribute to that party, in return for protecting some but not all of your customers...you are violating the license, and you must stop distributing altogether."

Microsoft's lawyers are bound to have a contrary opinion, but for now they are keeping it to themselves.

The firm issued the following statement, which says very little:

“We note that the draft of the GPLv3 does not tear down the bridge Microsoft and Novell have built for their customers. It is unfortunate, however, that the FSF is attempting to use the GPLv3 to prevent future collaboration among industry leaders to benefit customers.”®