Techdirt: A few years back, Microsoft trumpeted a series of high-profile licensing deals with manufacturers of smartphones and tablets whose Android-based products, it claimed, were infringing on its patents. As we pointed out, the deals proved nothing about the validity of that claim — just that Microsoft and the companies concerned had come to some mutually-acceptable arrangement, of which nearly all details were kept secret. In particular, Microsoft refused to reveal which of its many patents it claimed were infringed upon by Android. This allowed it to point to the licensing deals as “proof” that Android was infringing without ever actually needing to demonstrate that in the courts. It could then go to other manufacturers and encourage them to sign up too, which of course strengthened its story yet further for the round of negotiations after that.
Unfortunately for Microsoft, China has just put a stop to that clever, self-sustaining approach by revealing the patents involved. Microsoft was required to list them as part of the approvals process by the Chinese Ministry of Commerce (MOFCOM) for the US company’s acquisition of Nokia. As Ars Technica explains:
A list of hundreds of patents that Microsoft believes entitle it to royalties over Android phones, and perhaps smartphones in general, has been published on a Chinese language website.

The patents Microsoft plans to wield against Android describe a range of technologies. They include lots of technologies developed at Microsoft, as well as patents that Microsoft acquired by participating in the Rockstar Consortium, which spent $4.5 billion on patents that were auctioned off after the Nortel bankruptcy.
More specifically:
The Chinese agency published two lists on a Chinese-language webpage where it laid out conditions related to the approved merger. The webpage has an English version, but it doesn’t include the patent lists. There’s a longer list [MS Word Doc] of 310 patents and patent applications and then a shorter list [MS Word Doc] of just over 100 patents and applications that MOFCOM focused on.
Doubtless lawyers at many companies with products using Android are busy poring over those lists, which include US patent numbers as well as titles in English. At the very least, the release of these lists will make Microsoft’s attempts to sign up new licensees much harder, since now companies will know exactly what Microsoft is claiming in this regard before they enter into any negotiations. Moreover, it’s good news for the open source community, which is able to examine what claims Microsoft might be making about the free software elements of Android, allowing those to be challenged with prior art, say, or coded around.
But there’s another important aspect here. Microsoft had managed to keep the lid on its secret anti-Android list of patents for many years. What changed things was the emergence of China as a sufficiently important market that the US company felt obliged to accede to the Chinese government’s demands for a full list of the patents involved. The publication of the patent lists on the MOFCOM Web site is an indication that China will play by its own rules here, even — or perhaps especially — when it is dealing with what was once the world’s most powerful computing company.