According to Fortune magazine, Microsoft claim that Linux infringes 235 of its patents. 42 of the patent infringements are claimed to be in the kernel.

This could be interesting. If Microsoft sues major FOSS users like Red Hat, surely they will be counter-sued by major corporations like IBM and Oracle who have a vested interest in open source software.

The crux of the whole argument seems to be whether software is patentable. The Free Software Foundation's head layer, Eben Moglen, says, "the free world says that software is the embodiment of knowledge about technology, which needs to be free in the same way that mathematics is free... Everybody is allowed to know as much of it as he wants, regardless of whether he can pay for it, and everybody can contribute and everybody can share."

There's interesting discussion on the issue over at EdBrill.com. The author of the Fortune article, Roger Parloff, is discussing the details on his own blog. I'm betting it's being discussed at Slashdot, but I didn't see an attention-grabbing headline.