Shouldn't this loophole be closed? Something like: only allow the exclusive owner of a patent to sue potential infringers. That isn't enough to make shell companies a losing proposition, though, because they still contain the risk of losing a suit. I prefer the bond idea, it is a simple and more direct route to making NPEs liable for their actions.
Something along those lines might be an improvement but then you have the issue of a parent company in the US not being able to assign those rights to a European based subsidiary to defend them there.
I think it's probably dealing with the wrong problem which is the need for more fundamental reform of IP law.
