It isn't clear that Google is one of the companies who pays them. If Microsoft went after Google it seems like Google would have made a stink about it. Microsof

It isn't clear that Google is one of the companies who pays them. If Microsoft went after Google it seems like Google would have made a stink about it. Microsoft generally goes after companies they expect to be compliant (such as Amazon, who was already paying a patent fee for using Linux on their servers). It seemed like in the past their method was to say they have patents covering X (in the past X was Linux) and you can license them for some specified amount. I don't think they were specific. If you refused, they would throw out some specifics and take you to court (see TomTom). I haven't paid much attention to patents in the mobile space so I'm not sure if things have changed. I'm pretty sure Apple has a cross-licensing agreement with Microsoft, they appear to be more focused on a common enemy these days.