Over the last week we've taken note of how Microsoft continues to sign up licensees for a patent portfolio it claims it owns that specifically cover Android. And as we continue to note, we are completely amused by Microsoft's ability to in fact do so. In fact Android could conceivably be contributing between $500 and $750 million to Microsoft's coffers on a yearly basis (there is no way to confirm this but various analysts have suggested as much). Most recently Microsoft signed up giant Hon Hai and ZTE.

Meanwhile, following its acquisition of Motorola Mobility, Google and Moto went on a supposed offensive to begin "cashing in" on Motorola's mobile patent portfolio, and immediately targeted Microsoft with a lawsuit that Google hoped would land it at least $4 billion or so. We ourselves thought this was a long shot for a number of reasons - among them that the patents in question were not the sort of patents from which company could generate huge licensing revenue. By this we mean Fair, Reasonable, and Non-Discriminatory (FRAND) and "standards-essential" patents (SEP), which almost always earns nothing more than nominal licensing fees.

As it turns out, a federal court in Seattle agrees with our assessment, having just delivered a ruling yesterday by U.S. District Judge James Robart determining that Google and Motorola Mobility are entitled to about $1.8 million a year from Microsoft for the use of the patents in question, which have to do with the H.264 video standard and the 802.11 wireless standard. We're not going to dissect the ruling - suffice it to say that these are in fact legitimate FRAND patents, and Google and Motorola were crazy to ever think they'd be worth more than what the court has ruled them to be worth.

One of the key arguments for Google acquiring Motorola Mobility was that Google would in fact be able to unlock tremendous value from Motorola's patent portfolio, which would in turn hugely defray the cost of buying the company in the first place. Google blew it as far as we're concerned. There is far less money to unlock from Motorola's patent portfolio than Google imagined, which in turn makes the acquisition far pricier than Google had planned it to be. Can we conclude that Google overpaid for Motorola Mobility? We'd say so!

April has not been a good month for Google or Motorola as far as patents are concerned. Here is a summary:

• Corrected ITC ruling finds Android's text selection to infringe two more claims of an Apple patent.
• Apple defeats Samsung in California claim construction battle on all patents but one SEP. Apple is now reasonably close to certain infringement findings involving Android.
• Foxconn parent Hon Hai signs with Microsoft: 20th royalty-bearing Android patent license deal.
• Setback for Google: German court finds Microsoft licensed to Motorola's push notification patent.
• Court-determined FRAND rate for Motorola's standard-essential patents is a blow to Google (this is what we covered above).
• ZTE becomes 20th device maker to take Android patent license from Microsoft.
• German appeals court stays Google v. Apple case over (likely invalid) push notification patent.
• Google loses appeal against Microsoft's German injunction over multi-part text message interface.

That is quite a list of patent losses. For those interested in much greater detail, head over to Foss Patents. We don't feel bad for Google in this case. And we continue to be amused by Microsoft's ability to earn revenue off of Android.