Without knowing how much MS sold them for, there's another possibility. "We don't want to sue Linux, but we want to make them pay...Hmmm, what if we 'auction'

Without knowing how much MS sold them for, there's another possibility. "We don't want to sue Linux, but we want to make them pay...Hmmm, what if we 'auction' these patents, knowing they're of most value to OIN etc so a related organisation will pay top dollar." It's probably not as much money as a massive lawsuit, but it's much cleaner, and doesn't tarnish the reputation or line lawyer pockets.