Looks like Apple's going on the warpath, kids. Just a few months after Cupertino got into it with Nokia over phone patents, Apple's filed suit against HTC, alleging that the company is infringing 20 patents "related to the iPhone's user interface, underlying architecture, and hardware." Steve, you have something to say?
"We can sit by and watch competitors steal our patented inventions, or we can do something about it. We've decided to do something about it," said Steve Jobs, Apple's CEO. "We think competition is healthy, but competitors should create their own original technology, not steal ours."
Okay then. We're pulling the complaint filing now, we'll let you know the exact details as soon as we learn them.

Update: HTC just gave us a statement -- this is apparently coming totally out of the blue for them, since Apple hasn't even served the complaint yet.
We only learned of Apple's actions based on your stories and Apple's press release. We have not been served yet so we are in no position to comment on the claims. We respect and value patent rights but we are committed to defending our own innovations. We have been innovating and patenting our own technology for 13 years.
Update 2: We mean it when we say this was all just filed in the past few hours -- it's not yet in the court's systems. We just got the PDFs and put the full list of claims from the federal lawsuit below, but remember not to take the names of the patents literally or directly, since they don't mean much. We'll poke each one apart and tease out what's really at stake as we go along.

[We've now looked at each and every patent in both cases in-depth -- check it out here.]

Update 3: We've just learned that Apple submitted over 700 pages of exhibits to the District Court, which is a little nuts. In addition, the ITC complaint lists a number of specific HTC handsets as exhibits, including the Nexus One, Touch Pro, Touch Diamond, Touch Pro2, Tilt II, Pure, Imagio, Dream / G1, myTouch 3G, Hero, HD2, and Droid Eris. That's really a full range of HTC phones, running both Android and Windows Mobile, with and without Sense / TouchFLO. Interestingly, the Android sets are specifically included because they run Android, while the WinMo sets are called out specifically for including DSP chips, not anything to do with Windows Mobile.
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Apple / HTC Delaware filing

Gallery | 41 Photos

Apple / HTC ITC filing