It takes flowcharts to keep track of all the mobile patent lawsuits under way. Apple sued HTC, while Kodak sued Apple, Samsung and Sony. RIM filed suit against Kodak and Motorola. And what are called nonpracticing entities (or patent trolls, if you prefer) such as Intellectual Ventures and NTP have sued pretty much the lot of them. It can seem - and some have argued - that the patent system itself is broken, forcing companies to spend more time and money on legal battles than research and development.