Because Google is not actually doing anything infringing.
Google is writing code, but software patents in the US do not apply to abstract code. They apply to specific devices. So if a patent is being infringed, it is done by the phone manufacturers and shippers, and not Google.
If that sounds odd, then it is, but that is how the patent system currently works.
Edit: Case in point, the Nexus S is named in the suit despite being pure Android and having a fairly unique design.
If the main thrust of the suit is around the physical design, they probably have to go after the OEMs, not Google. Seems like Google could probably duck that.
It might be because Google is too powerful. It might be because Google isn't the one putting the OS on phones and selling them, companies like HTC and Samsung are -- maybe that makes it difficult to successfully sue Google directly. In any case, it's clear that Apple and Microsoft are willing to do anything to keep Android from becoming a dominant mobile OS. As John Gruber wrote [1]:
"The patent suit against HTC [...] is all about Google - about creating a situation where Android is no longer a free operating system for handset makers in the U.S., because the cost of using it is an expensive legal defense against Apple."
Perhaps also of interest: a John Gruber piece [2] arguing against software patents, using quotes from Paul Graham, Tim Bray, and Will Shipley.
[1] http://daringfireball.net/2010/03/napalm_in_the_morning
[2] http://daringfireball.net/2010/03/this_apple_htc_patent_thin...
If you go after Google you go after a company that obviously has a big stake in mobile share and will want to fight for it.
If you go after individual phone makers, they have to decide if it is worth continuing going down this path. Even more likely, a new phone maker might get scared off at producing a clone that doesn't have the financial resources to fight Apple.
It looks like this is more around form factor which is on Samsung, and only slightly related to screen UI.
Sure but it's just using google maps API with a fancy UI.
> Also keep in mind that there is almost certainly some sort of SLA/contract ensuring continued access to Google Maps data for some time period
And I'm pretty sure there's a clause that would void that contract should apple sue google over patents.
> say, Bing-powered map graphics
Bing map is way inferior to google maps, otherwise apple would have switched a long time ago.
The major companies making maps are TeleAtlas, Navteq, and Google. TeleAtlas is owned by TomTom, Navteq is owned by Nokia. Navteq is used by Google, Microsoft and Mapquest. If Apple ever wanted to switch to another map provider, it wouldn't need a middleman like Microsoft.
Sure but it's just using google maps API with a fancy UI.
If so, then I reckon that's temporary, given that Apple bought companies like Placebase, Poly9, and Siri.
http://www.appleinsider.com/articles/10/07/14/apple_acquires...
http://www.appleinsider.com/articles/09/10/01/apple_purchase...
http://www.appleinsider.com/articles/10/04/28/apple_acquires...