What is a U.S. Patent?
A U.S. patent is essentially a right which the government grants to the inventor permitting him “to exclude others from making, using, or selling the invention” within the U.S., its territories and possessions. You may obtain a patent on any “new, useful process, machine, or composition of matter, or any new and useful improvement thereof.” However, contrary to a common misconception, a U.S. patent does not grant the inventor a right to make or use the invention himself–he may do so only if he does not infringe someone else’s unexpired patent.
The U.S. government grants patents for a term of 20 years from the filing date (14 years from issue date for design patents). Congress may extend the term only in special circumstances. After the term expires, you lose your exclusive right to the invention. Everyone is now free to exploit the product which you disclosed in the patent. In addition, failure to pay maintenance fees will result in the patent prematurely expiring