Well, it was bound to happen: Linux vendors Red Hat and Novell have been sued for patent infringement. Groklaw is reporting that on Tuesday, the two companies were sued by IP Innovation LLC and Technology Licensing Corp. for violating three patents having to do with windowing user interfaces.
The lawsuit represents the first test of what happens when open source collides with patents, and it's interesting for a couple reasons. First, notice that all the other Linux vendors are missing from the defendants list, most notably IBM. That could be because IBM has already licensed the patents in a different context. (In June, Apple settled a patent infringement lawsuit with the same plaintiffs over at least one of the patents involved here.)
Stollen from Frank Hayes Blog