In many countries, the first person to file for a patent is entitled to it. However, in the United States, the right to a patent is determined by who invented it first. If Mr. Grey had been able to prove he had created the first telephone, then the fact that he filed for his patent just a few hours after Mr. Bell filed would not have mattered. Whether the inventor abandons an invention or exercises due diligence in developing a working prototype also affects patent rights.
Regularly kept computer files and other reliable lab data are sources of proof, but a bound lab notebook is still the most dependable evidence in proving prior invention. The inventor must date and sign the lab book, and a witness must countersign it. Notes should be written in dark ink, so that information cannot be erased or changed. Legible handwriting is critical. The inventor ...
