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.
There are maintenance fees to be paid during the life of a utility patent, and if they are not paid on time the patent will expire earlier than the maximum 20-year-from-filing term. After the patent expires, the invention is available to all. Design Patents are valid for a period of 14 years from the date of issue.