A free public resource for patent system navigation worldwide.An initiative of Cambia

• Home
• Patent Search & Tools
  • Patent Search
  • Patent Search Help
  • Blast & Sequence Search
  • Patent Lens FAQs
• Patent Landscapes
  • Explore Patent Landscapes
  • Sequence Project (BLAST)
  • Patent Landscapes FAQs
• Intellectual Property
  • Patent Tutorials and FAQs
  • IP Policies and Practices
  • Patent Laws Around the World
• Media Centre
  • Cambia, BiOS, Patent Lens In The News
  • Press Releases
  • Audio & Video
• About Us
  • Our People
  • Careers
  • Contact Us

There are a number of additional factors that may affect the term of the patent. These include:

• Terminal disclaimers
• Patent term adjustments
• Patents that have lapsed due to failure to pay maintenance fees

Terminal Disclaimers

A terminal disclaimer is filed when the patentee wants to, or is required to disclaim a portion of, or all of a patent term. When a portion of a patent term is "disclaimed", it is said to have been "dedicated to the public". In effect, terminal disclaimers shorten the term of a patent, and lead to a patent term that expires sooner than would normally be predicted.

Terminal disclaimers are commonly filed to overcome an obviousness-type double-patenting rejection. This type of rejection is generally given when an applicant has two closely-related applications or patents. If the invention in the later-filed application is an obvious improvement of the invention in the first application, the Examiner may require that the later-filed patent expire on the same date as the first-filed patent. When this occurs, the patent term of the second application is shortened, or disclaimed.

See the section of the MPEP that relates to terminal disclaimers. This information is also in 37 CFR 1.321.

Patent Term Adjustments

Sometimes the patent term is extended for reasons of national interest. For example, in the European Community, law provides for extension of the patent term for patents disclosing new drugs for human use, to compensate for patent term lost while the patentee is unable to market a product because government approval is still pending. This is intended to provide a greater incentive for investment into research, opposing the counter-incentive of lengthy regulatory approval processes. Similar patent term restoration is provided by Japan, Israel, the U.S. and many other countries.

In some countries restoration of patent term for time spent in regulatory approvals extends to other types of medical devices, veterinary products and the like, but most often agricultural biotechnology patent applications are not considered under this rubric despite lengthy regulatory approval processes for food crops.

In the US, if the issue of a patent is delayed due to interference proceedings (a procedure attempting to resolve disputes over who was first to invent a particular technology), a secrecy order, or in other limited circumstances such as delays in patent office handling, the term of the patent can be extended for the period of delay, up to a total of five years. If it has been so extended, the extended portion of the term of the patent can be reduced for any period of time during which the applicant did not act with due diligence, such as replying in timely fashion to a patent examiner's question or office action. See a USPTO web page describing how patent term adjustments are calculated.

Lapsed Patents Due to Failure to Pay Maintenance Fees

Patents can lapse if required maintenance fees are not paid. Many countries require the payment of annuities annually, or maintenance payments at other intervals. Sometimes assignees knowingly or unintentionally fail to make such payments, so a patent that would otherwise be predicted to have a longer term may not actually be in force.