I just read Microsoft's announcement of patent infringement action against Motorola in a US district court as well before the US International Trade Commission (which can ban imports of infringing devices).
Here's my initial reaction:
This is very significant but only the latest in a series of patent cases involving Android, after Apple suing HTC and Oracle going after Google itself.
These patent suits brought forward by industry giants with massive patent portfolios unmatched by Google are dark clouds over Android. Google must now act constructively and try to work out amicable arrangements with those right holders. Otherwise I'm afraid that third-party application developers investing their money, creativity and hard work in the Android platform will be harmed because of an irresponsible approach to intellectual property in a market in which patents have always played an essential role. Android phone vendors and other parties will also be affected, but application developers are the ones I'm most concerned about in all of this.
I will try to obtain more information and will comment in more detail soon (during or right after the weekend).
[Update 1] Microsoft Corporate Vice President and Deputy General Counsel Horacio Gutiérrez has published a blog posting on TechNet outlining Microsoft's view.
[Update 2] This Seattle Post-Intelligencer article contains links from which to download the documents filed with the district court as well as the International Trade Commission. Those documents list the patents and products concerned.
[Update 3] Meanwhile I have published two follow-up postings. This article explains the US International Trade Commmission's role as a patent enforcement agency that could ban entry of Motorola's Android-based phones into the US market within 18 months. And this article talks about how the patent situation surrounding Android might escalate. It also contains an overview of all patents asserted by Apple, Oracle and Microsoft against Android, sorted by category. Microsoft's related patents are explained in some more detail.
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