Until the day the patent issues, no rights can be claimed in the invention, even though the invention may have been made, sold, and used by the inventor and others during pendency of the application. Except in cases where the application has been published prior to the issuance of the patent, no claim of damages from infringement may be made with respect to actions taken prior to the Patent Date -- although further unauthorized manufacture and sales may be stopped, and use of unauthorized embodiments of an invention may be prohibited once the patent issues.

The Patent Date was once the determining factor in calculating the term of the patent. Prior to June 8, 1995, U.S. patents were given a term of 17 years from the Patent Date (provided they were properly maintained during that term). Since June 8, 1995, when the U.S. joined the Uruaguay Round Agreements -- regarding international cooperation in patent rights -- the term of a patent grant has changed: In general, the term of patents issuing from applications filed after June 8, 1995, is 20 years from the filing date of the application (again subject to proper maintenance). However, for a number of patents, including some that were in force on June 8, 1995, and all that issued after that date from applications filed before that date, the term, in most cases, is either 20 years from the application filing date or 17 years from the Patent Date, whichever is greater. A number of complex factors affect determination of the application filing date and the term of a particular patent, and a competent patent attorney should always be consulted.

The term of a design patent has always been, and remains, 14 years from the Patent Date.