Thinking about it - why big companies don't move then? To avoid software patent cases? I mean they can still have skilled workers working in Silicon Valley, can't they? But the company is registered somewhere where they can't sue them. Or what am I missing here?
I would assume having an office in the country means a presence which means they follow the law. Plus just doing any kind of business inside the country, including contractors, makes them subject to local law.
I would not recommend taking advice on complicated matters of international intellectual property law from a Q&A site on the Internet. Go talk to a lawyer.
Edit: A quick Google found this, seems I would be OK. http://answers.onstartups.com/questions/21560/what-happens-w...