How Long Does a Patent Last?

Before June of 1995, the patent laws in the United States provided that the term of a utility or plant patent ended seventeen years from the date of patent grant. To comply with Article 33 of the Trade-Related Aspects of Intellectual Property Rights (TRIPS) Agreement resulting from the Uruguay Round Agreements of the General Agreement on Tariffs and Trade (GATT), the United States was required to establish a minimum term for patent protection ending no earlier than twenty years from the date the application was filed. Thus, the Uruguay Round Agreements Act amended 35 U.S.C. § 154, and these amendments took effect on June 8, 1995.

Generally speaking, utility and plant patent applications filed on or after June 8, 1995, have a term that begins on the date the patent issues and ends on the date that is twenty years from the date on which the application for the patent was filed in the United States. If the application that ultimately issues contains a specific reference to an earlier filed US or international application, the term ends twenty years from the filing date of the earliest such application. This patent term provision is referred to as the “twenty-year term.”

All utility and plant patents that were in force on June 8, 1995, or that issued on an application that was filed before June 8, 1995, have a term that is the greater of the “twenty-year term” or seventeen years from the patent grant. A patent granted on an international application filed before June 8, 1995, and which entered the national stage before, on or after June 8, 1995, will have a term that is the greater of seventeen years from the date of grant or twenty years from the international filing date or any earlier filing date relied upon for priority purposes.

The twenty-year patent term is the general rule. During the life of the patent it will still be necessary to make maintenance fee payments in order to keep the patent alive. Further, if there is delay introduced on the part of the Patent Office additional patent term will be added on to compensate the patent applicant for unwarranted administrative delay. The topic of administrative delay and the extension of patent term goes beyond this basic primer and relates to patent term extension (for patents issuing on applications filed on or after June 8, 1995, but before May 29, 2000) or patent term adjustment (for utility and plant patent applications filed on or after May 29, 2000). We will tackle patent term extension and patent term adjustment in another article at a later time. If you are interested in that topic please see Chapter 2700 of the MPEP.

What follows is discussion of some special circumstances relating to specific types of patent applications.

Design Patents

Design patents have a term of fourteen years from the date of the patent grant. 

Continuing Applications

A patent granted on a continuation, divisional, or continuation-in-part application that was filed on or after June 8, 1995, will have a term which ends twenty years from the filing date of earliest application for which a benefit is claimed as a result of either a US or international application, regardless of whether the application for which a benefit is claimed was filed prior to June 8, 1995.

International Patent Applications

A patent granted on an international application filed on or after June 8, 1995, which enters the national stage in the United States, will have a term which ends twenty years from the filing date of the international application. A continuation or a continuation-in-part application claiming of an international application will have a term which ends twenty years from the filing date of the parent international application.

Foreign Priority

Foreign priority is not considered in determining the term of a patent. Accordingly, an application claiming foreign priority has a term which ends twenty years from the filing date of the application in the United States and not the priority date.

Provisional Applications

Domestic priority under 35 U.S.C. 119(e) to one or more U.S. provisional applications is not considered in the calculation of the twenty-year term. The twenty-year term is calculated from the filing date of the non-provisional application that claims priority from the earlier filed provisional application.