A couple of weeks ago I wrote about Microsoft's suit against TomTom, which alleged infringement of eight of its patents - including three that relate to TomTom's implementation of the Linux kernel.
I wrote there that this seemed part of a larger attack on Linux, and not just one on TomTom, as Microsoft nonetheless insisted.
This called forth a fair amount of disagreement, so I was glad to come across this post on Harald Welte's blog:
[MS] claim that this lawsuit has no relation whatsoever to Linux, and they're only targeting TomTom's specific implementation of Linux. I have actually reviewed the TomTom kernel sources a number of times during the last couple of years as part of gpl-compliance reviews. I can tell you, there is nothing "TomTom specific" in their FAT FS code. It is the plain fat/msdos/vfat file system like in every kernel.org kernel.
That seems pretty definitive. The question now is what Microsoft hopes to achieve by bringing this lawsuit. A fascinating explanation is provided as a comment to my original post from Jeremy Allison. He's one of the leaders of the Samba project, and knows more than most about how Microsoft thinks and operates, since he's been heavily involved in the EU's efforts to get interoperability information from the company. Here's what he wrote:
Top in Open Source
What people are missing about this is the either/or choice that Microsoft is giving Tom Tom.
It isn't a case of cross-license and everything is ok. If Tom Tom or any other company cross licenses patents then by section 7 of GPLv2 (for the Linux kernel) they lose the rights to redistribute the kernel *at all*.
Microsoft has been going around and doing these patent cross licensing deals with companies under NDA's so they never come to light for *years*.
That was the whole point of the Novell deal - Microsoft lawyers finally thought they'd found a way to *publicly* do these cross licensing deals and get around the GPLv2, but the GPLv3 put paid to that.
Tom Tom are the first company to publicly refuse to engage in this ugly little protection racket, and so they got sued. Had Tom Tom silently agreed to violate the GPL, as so many others have, then we'd only hear about a vague "patent cross licensing deal" just like the ones Microsoft announces with other companies.
Make no mistake, this is intended to force Tom Tom to violate the GPL, or change to Microsoft embedded software.
So it turns out that the TomTom lawsuit goes to the heart of Microsoft's attacks on Linux, and its effort to stop people using it in embedded systems – an increasingly popular option, and one, therefore, that is increasingly problematic for Microsoft.
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Update: Steven J. Vaughan-Nichols has corroboration of this analysis from no less a person than Horacio Gutierrez, Microsoft's "corporate vice president and deputy general counsel of intellectual property and licensing".