Disclaimers

By Eugene T. Perez

A statutory “disclaimer” may be filed to either totally disclaim one or more claims of the patent, or to disclaim the entire term or any terminal part of the term of the patent (i.e., a “terminal disclaimer”).1

A disclaimer of one or more of the claims in the patent may be desired by the patentee after patent issuance, or even after a decision in a district court infringement action or declaratory judgment action finding one or more of the claims of the patent to be invalid. The disclaimer must be made with respect to a complete claim, not part of a claim. It is permissible to maintain a dependent claim which depends from a disclaimed independent claim. The patent owner, with the payment of the appropriate fee, may disclaim one or more of the claims found to be invalid by filing a disclaimer in writing for recordation in the USPTO.2 Thereafter the filed disclaimer will be considered as part of the original U.S. patent.

A patentee usually files a terminal disclaimer to disclaim the terminal part of the term of a granted patent if the patentee desires to remove an issue regarding double patenting.3 This type of terminal disclaimer filed with respect to a granted patent is essentially the same as that used for overcoming obviousness-type double patenting rejections encountered during prosecution of an application. It is important to note that terminal disclaimers affect not only the term of any patent granted on a patent application in which a terminal disclaimer is filed, but also restrict the right of the common assignee executing the terminal disclaimer to sell the patent rights of the granted patent to another while retaining the patent rights to the patent with respect to which the terminal disclaimer is made. In other words, both patents have to remain commonly assigned throughout their patent term.


  1. 35 United Stated Codes (“U.S.C.”) § 253 and 37 Code of Federal Regulations (“C.F.R.”) § 1.321.
  2. 37 C.F.R. § 1.321(a).
  3. 37 C.F.R. § 1.321(b).