Microsoft just announced that it's gotten yet another unfortunate Android phone maker to pay up or be sued for patent infringement. What this means for Android is pretty clear, it's a big threat, one that Google doesn't seem to be doing much about.
But the deal also had to do with Chrome OS. It's not the first to mention Chrome OS either. This is important because Chrome OS is completely different to Android, there's hardly anything linking them.
Chrome OS is the Linux kernel, some low-level and purpose built libraries along with some GNU, Linux libraries and Google Chrome, the browser.
If Microsoft is claiming that it holds a patent for any of these than any Linux maker is going to be in peril. Not that Microsoft hasn't threatened Linux before.
Notably, Microsoft doesn't have a patent deal over Chrome with Samsung, which actually builds Chromebooks.