How long do U.S. patents last?
Since June 8, 1995, the term of any U.S. Utility patent has been basically 20 years. The 20 years is measured from the date the application for patent was filed, not the issue date of the patent. After the patent expires, it cannot be renewed and anyone is free to copy the invention described in it.
Last update on September 28, 2009 by Administrator.