
This article gives us the list of all the companies that Microsoft is licensing to and suing and highlights the interesting fact the company led by CEO Steve Ballmer is "double dipping" - that is "seeking licensing fees both from the "original equipment manufacturer" (OEM) who mostly designs the device (e.g. Samsung) and from the "original device manufacturer" (ODM) who primarily handles manufacturing the device (e.g. Foxconn)" - with a certain success since 55 percent of the Android ODMs and 53 percent of Android OEMs entered into licensing agreements. The following paragraph, which a quick outline of the 9 main patents that Android is said to infringe, is also definitely worth a read.
Finally Jason Mick argues that the validity of Microsoft patents will be much harder to call into question, since they appear to reach a high threshold of novelty and non-obviousness (contrary to Apple) and finishes with an interesting comment "(...)one crucial thing to remember is that these patents will expire. Many are expiring within two years, and almost all will be expired within a decade. As a result, within a decade Microsoft's license agreements with Android OEMs and ODMs will almost certainly be drastically restructured. (...) Microsoft can revel in its licensing successes for now, but if it doesn't continue to push ahead in the mobile realm, its gains will be short-lived." It seems that Microsoft understood that fact very well, since the company received more than 3000 patents in 2010...