In the
United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territo ...
, under current
patent law A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...
, the term of patent, provided that maintenance fees are paid on time, is 20 years from the filing date of the earliest U.S. or international ( PCT) application to which priority is claimed (excluding provisional applications). The
patent term The term of a patent is the maximum time during which it can be maintained in force. It is usually expressed in a number of years either starting from the filing date of the patent application or from the date of grant of the patent. In most patent ...
in the United States was changed in 1995 to bring U.S. patent law into conformity with the
World Trade Organization The World Trade Organization (WTO) is an intergovernmental organization that regulates and facilitates international trade. With effective cooperation in the United Nations System, governments use the organization to establish, revise, and e ...
Agreement on Trade-Related Aspects of Intellectual Property Rights The Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) is an international legal agreement between all the member nations of the World Trade Organization (WTO). It establishes minimum standards for the regulation by nat ...
(TRIPs) as negotiated in the
Uruguay Round The Uruguay Round was the 8th round of multilateral trade negotiations (MTN) conducted within the framework of the General Agreement on Tariffs and Trade (GATT), spanning from 1986 to 1993 and embracing 123 countries as "contracting parties". The ...
. As a side effect, it is no longer possible to maintain
submarine patent A submarine patent is a patent whose issuance and publication are intentionally delayed by the applicant for a long time, which can be several years, or a decade.
s in the U.S., since the patent term now depends on the priority date, not the issue date.
Design patent In the United States, a design patent is a form of legal protection granted to the ornamental design of an article of manufacture. Design patents are a type of industrial design right. Ornamental designs of jewelry, furniture, beverage containers ...
s have a shorter term than utility patents. Design patents filed on or after May 13, 2015 have a term of 15 years from issuance. Design patents filed prior to May 13, 2015 have a term of 14 years from issuance.


The original patent term under the 1790 Patent Act was decided individually for each patent, but "not exceeding fourteen years". The 1836 Patent Act (5 Stat. 117, 119, 5) provided (in addition to the fourteen-year term) an extension "for the term of seven years from and after the expiration of the first term" in certain circumstances, when the inventor hasn't got "a reasonable remuneration for the time, ingenuity, and expense". In 1861 the seven-year extension was eliminated and the term changed to seventeen years (, 248). The signing of the 1994
Uruguay Round Agreements Act The Uruguay Round Agreements Act (URAA; ) is an Act of Congress in the United States that implemented in U.S. law the Marrakesh Agreement of 1994. The Marrakesh Agreement was part of the Uruguay Round of negotiations which transformed the Gener ...
then changed the patent term from seventeen years from the date of issue to the current twenty years from the earliest filing date.

Adjustments possible under current law

PTO processing extension

If the
United States Patent and Trademark Office The United States Patent and Trademark Office (USPTO) is an agency in the U.S. Department of Commerce that serves as the national patent office and trademark registration authority for the United States. The USPTO's headquarters are in Al ...
fails to examine a patent application in time (deadlines for various steps are different), the patent term may be extended.;
American Inventors Protection Act The American Inventors Protection Act (AIPA) is a United States federal law enacted on November 29, 1999, as Public Law 106-113. In 2002, the Intellectual Property and High Technology Technical Amendments Act of 2002, Public Law 107-273, amended ...
(AIPA), enacted on November 29, 1999.
Extensions or other delay taken by the applicant can reduce or eliminate the extension. This extension is known as a Patent term adjustment (PTA). Its intention is to accommodate for delays caused by the US patent office during the Prosecution of a US patent application. The total PTA is an addition to the 20-year lifespan of a US patent. The delays are broadly classified into 4 types: * Type A - this delay is caused when USPTO fails to reply within the time period provided. As per US Patent law USPTO has to issue the First Office action within 14 months of filing of the application. All other office actions has to be issued within 4 months of receipt of an applicant response. Failing to this condition, type A delay will accounted. * Type B - USPTO estimates the normal prosecution period of an application to be 3 years, i.e. between the date of filing of the application and the issue of the patent. If the prosecution exceeds this time, then Type B delay come into place. Type B delay will calculated if no RCE (Request For Continued Examination) is filed Prior to completion of 3-year period. If the first RCE is filed after 3-year period then type B delay will be calculated up to the date of filing of RCE. * Type C - This type of delay is calculated in the events of secrecy orders or interferences. * Applicant Delay - Applicant delay occurs when the applicant fails to respond to the office action within 3 months of mailing of an office action. Calculation: *Type A delay= Date of issuance of office Action -(Date of receipt of applicant response + 4 Months/14 Months) *Type B delay=Date of issue of Patent/Date of filing of first RCE - (Date of filing of application + 3 years) *Total PTA =Type A+Type B + Type C - Applicant Delay -overlapping delays

Foreign filing priority

Patent Cooperation Treaty The Patent Cooperation Treaty (PCT) is an international patent law treaty, concluded in 1970. It provides a unified procedure for filing patent applications to protect inventions in each of its contracting states. A patent application filed und ...
provides a process for a patent filing to claim the priority date of an earlier foreign patent application. Within one year of filing a patent application in one country, an international patent application (which "designates" certain other countries, by default all contracting states) can be made. This holds the original priority date and starts the 20-year validity clock, while allowing the actual patent application in the designated countries (and the associated expenses) to be deferred an additional 20 months. Such a patent would expire earlier than 20 years after U.S. filing.

Reissue and reexamination

Even if the scope of a patent is narrowed, neither
reissue In the music industry, a reissue (also re-release, repackage or re-edition) is the release of an album or single which has been released at least once before, sometimes with alterations or additions. Reasons for reissue New audio formats Rec ...
reexamination In United States patent law, a reexamination is a process whereby anyone—third party or inventor—can have a U.S. patent reexamined by a patent examiner to verify that the subject matter it claims is patentable. To have a patent reexamined, ...
changes the original expiration date. A reissued or reexamined patent expires on the day the original granted patent would have ordinarily expired. Example: The validity of a patent (filing: January 1, 2000; issue: January 1, 2002; end: January 1, 2020) is challenged. The USPTO issues a Certificate of Reexamination on January 1, 2004. The reexamined patent is in force until January 1, 2020, assuming payment of all maintenance fees.

Terminal disclaimer

A terminal disclaimer is a process by which a patent's term is shortened because it duplicates the claims of another patent which expires sooner. If any claim of a pending patent application would have been obvious in light of at least one claim of the applicant's issued patents, the USPTO may reject that claim for obviousness-type double patenting and require the applicant to disclaim a part of the term of the pending application. For example, an applicant's patent A expires on December 24, 2000. The applicant filed another patent application two years later. Under some conditions, the second patent might expire later than the first (based upon the respective earliest claimed priority dates). If the applicant is required to file, and does file, a terminal disclaimer in the later filed patent, then the later filed patent will expire at the same time as the earlier filed patent, the extra term having been disclaimed ("terminal disclaimer"). In filing the terminal disclaimer, the later filed patent and the earlier filed patent must be, and remain, commonly owned. In the case of co-pending applications, either or both of the applications may have claims rejected for obviousness-type double patenting, and a terminal disclaimer may be required in either or both, in which case the earlier expiration date will control. After the Uruguay Round Agreements Act of 1994 (URAA), some patents with terminal disclaimers were eligible for a term adjustment because their referenced patents received a term adjustment under the URAA. Patents whose parents received extensions were eligible to file to receive a similar extension, because the claims they depended on were still protected. This has been discussed in the ''
Manual of Patent Examining Procedure The ''Manual of Patent Examining Procedure'' (MPEP) is published by the United States Patent and Trademark Office (USPTO) for use by patent attorneys and agents and patent examiners. It describes all of the laws and regulations that must be foll ...
''. A terminal disclaimer does not negate Patent Term Extension that has been granted under 35 U.S.C. 156. In a pharmaceutical patent dispute, Teva argued that Wyeth’s patent on zaleplon drug products (Sonata) had expired because of a terminal disclaimer. Wyeth (and its exclusive licensee King) argued that patent’s term was ongoing because of a Patent Term Extension due to FDA regulatory review delay. Under 35 U.S.C. 156(a), the term of a patent "shall be extended" after a series of provisions are satisfied. The district court found the language of the statute unambiguous and gives the court "no discretion". Thus, if the enumerated conditions are satisfied, the patentee is entitled to a term extension calculated pursuant to Section 156. Teva's motion to dismiss was consequently denied because "a terminally disclaimed patent is eligible for extension under ection156." The case is interesting because the patentee in the first instance had expressly disclaimed term subsequent to 2003 to get the patent granted. However, the holding of this case does not apply to Patent Term Adjustment granted under 35 U.S.C. 154. Such term adjustments will be subject to any terminal disclaimer that has been filed. There is now a similar case wherein a company was given extension under S.156 and the generic entrant arguing against such extension between Merck and Hi-tech for the drug dorzolamide (Trusopt). Here too, the first company (Merck) had filed a standard form terminal disclaimer. This patent was later given an extension and became the crux of the litigation.

FDA approval extension

Drug Price Competition and Patent Term Restoration Act The Drug Price Competition and Patent Term Restoration Act (Public Law 98-417), informally known as the Hatch-Waxman Act, is a 1984 United States federal law that encourages the manufacture of generic drugs by the pharmaceutical industry and es ...
(Hatch-Waxman Act) of 1984 provides patent holders on approved patented products with an extended term of protection under the patent to compensate for the delay in obtaining
Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...
(FDA) approval. ''Merck & Co., Inc. v. Hi-Tech Pharmacal Co., Inc.''80 F.3d 1543 (Fed. Cir. 1986)
/ref> ruled that patents extended under Hatch-Waxman are still eligible to URAA term extension. However, patents in force on June 8, 1995 solely because of the Hatch-Waxman term adjustment are not eligible.

See also

Supplementary protection certificate In the European Economic Area (European Union member countries, Iceland, Liechtenstein and Norway), a supplementary protection certificate (SPC) is a ''sui generis'' intellectual property (IP) right that extends the duration of certain rights a ...


Further reading

* For a detailed description of the laws and rules governing patent terms in the U.S., see the ''
Manual of Patent Examining Procedure The ''Manual of Patent Examining Procedure'' (MPEP) is published by the United States Patent and Trademark Office (USPTO) for use by patent attorneys and agents and patent examiners. It describes all of the laws and regulations that must be foll ...
Chapter 2700

External links

* {{USC, 35, 154 - Contents and term of patent; provisional rights

Manual of Patent Examining Procedure The ''Manual of Patent Examining Procedure'' (MPEP) is published by the United States Patent and Trademark Office (USPTO) for use by patent attorneys and agents and patent examiners. It describes all of the laws and regulations that must be foll ...
USPTO PTA calculation

Calculating Patent Term Adjustment Post-Novartis

United States patent law Time in government