As it turns out, there are as many origin stories for barbecue as there are spellings of the word on neon signs. These explanations range from a linguistic attempt to connect barbecue to boucan (also French) to a tall tale tracing barbecue to a Texas rancher who happened to brand the initials B.Q. on his livestock.
Patent protection usually ends when the patent expires. Here are the expiration dates: For all utility patents filed before June 8, 1995, the patent term is 20 years from date of filing, or 17 years from date of issuance, whichever period is longer.
A patent may expire if its owner fails to pay required maintenance fees. Usually this occurs because attempts to commercially exploit the underlying invention have failed and the patent owner chooses to not throw good money after bad. Patent protection ends if a patent is found to be invalid.