Maybe. Kind of. Not so much... could be the answer to this question after recent changes in the Patent Law. The US has moved from a first to invent system (which is almost like it sounds) to a first inventor to file system. Under the old first to invent system, in the event of an applicant encountering a problem getting a patent through the patent office, or another trying to allege that a real inventor committed patent infringement, an inventor could always pull out his inventor notebooks and prove that he invented his widget or process before another, assuming he was also diligent about filing a patent application. By proving he was the first to invent, all the inventor's problems (or at least those relating to inventorship) would melt away. With the new law, the US has edged closer to how the rest of the world treats its inventors and has moved to a system where the first to file (almost) gets the patent.