How Terminal Disclaimer Effects Life of a U.S. Patent?

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What is Terminal Disclaimer? 

A terminal disclaimer is a statement by which an applicant disclaims or dedicates to the public some part of term of the patent or complete term of a patent which is under examination at USPTO. Thus, an application for the patent, when filed in USPTO, faces rejections such as double patenting (discussed below in detail), then a terminal disclaimer is filed. 

This is done in order to overcome double patenting rejection by patent examiner in USPTO. If the United States Patent and Trademark Office (USPTO) gives a second patent to the inventor, similar to one already owned by the inventor, the applicant will have to file a terminal disclaimer for the second patent in order to overcome double patenting rejection.  

Thus, one should note that by filing a terminal disclaimer, the applicant/inventor are disowning or disclaiming some term of their patent to be granted, thus the life of the patent will not extend rather it will decrease or be cut to be not more than life of the parent application. Therefore, we can say that the disclaimed patent (patent under examination, yet to be granted) cannot extend beyond the life or term of the parent patent or prior patent, on the basis of which, double patenting rejection was asserted. Terminal disclaimers can nullify or disclaim potential patent term adjustment for the disclaimed patent in such a way that its life or term will not exceed the life of other patent. 


Table of Contents

As the name suggests, terminal disclaimer will disclaim term of the patent, i.e., the rights of the patent will be disclaimed after a certain term. 

Now one must be wondering, why have I never noticed it. Well, it is right there at top left of patent PDF under the notice section along with patent term adjustment, patent term extension, etc. 

Potential PTA for the disclaimed patent may be invalidated by terminal disclaimers. Particularly, PTA cannot be used to extend a patent’s term over the deadline specified in a submitted (and accepted) terminal disclaimer. 

Who files Terminal Disclaimer? 

An inventor or an applicant who owns entire patent right, title and interest can file terminal disclaimer. The inventor can be named as applicant in the patent application. Also, an assignee or an applicant who owns all rights to the patent can file terminal disclaimer.   

Further, for the applications filed before September 16, 2012, an inventor may legally have someone else file the terminal disclaimer. However, for the patent applications filed after this date, only the original applicant can file a terminal disclaimer, except if the applicant has listed a lawyer or patent agent in first application, they can also file terminal disclaimer on behalf of applicant. 

When to file Terminal Disclaimer? 

When an applicant files an application by making very small changes to already existing patent owned by the same applicant, the newly filed application may be granted to the applicant but under certain conditions.  

In other words, a patent can’t be filed twice by just introducing small changes. The USPTO applies double patenting rejection. In order to overcome this, one must file a terminal disclaimer. 

Filing a terminal disclaimer will help you have a patent with small changes to the already existing patent just by reducing or disclaiming or disowning the term of the newly filed application to be not more than that of the original patent. Hence, the second patent (on which terminal disclaimer is filed) will also expire when the first one also expires. Also, the terminal disclaimer is filed on the second patent only when the inventor/applicant owns all rights to both the patents. If under any circumstances, the first patent expires, or is sold, the inventor or applicant would not be able to enforce the second patent.  

Further, if multiple patents or applications are mentioned or disclosed in the terminal disclaimer, the earliest filing date of a patent/application mentioned is considered for disclaiming the term of the patent. 

The only exception is when the first patent is abandoned such as due to non-payment of fees, the second patent (with terminal disclaimer) will complete its term, but not beyond the true life of the first patent had it not been abandoned. 

Additionally, terminal disclaimer should be used following any alterations to the patent term, which will be covered in more depth below. Furthermore, a terminal disclaimer may be revoked prior to the grant of the patent by submitting a petition under 37 C.F.R. 1.182 asking for the revocation of the recorded terminal disclaimer. A terminal disclaimer, however, once a patent has been granted, it cannot be cancelled. 

Double Patenting 

There are two types of double patenting – 1) Statutory double patenting and 2) Non-statutory double patenting or also called obvious double patenting.  

The statutory double patenting rejection is applied when two patents have identical claims.  

The non-statutory double patenting is applied when two patents have very similar claims but not identical claims. For such type of double patenting, a terminal disclaimer is filed.  

If a patent with similar claims is issued somehow, one can file terminal disclaimer after issuance as well.  The non-statutory double patenting comes into play when the two patents have common inventor, applicant or assignee and when second patent is rendered obvious from the disclosure of first patent.   

In some cases, when the claims of an invention are going in two different directions indicating two different inventions, the inventor, applicant or assignee are suggested by USPTO to file two patents for the two different inventions. In such scenarios, one cannot file a terminal disclaimer. 

Case Studies

Calculation of life for US Patents without terminal disclaimer: 
Earliest filing date + 20 years= Anticipated Expiry date 
Earliest filing date + (PTA or PTE if any) + 20 years= Adjusted Expiry Date 

Calculation of life for US Patents with terminal disclaimer:
Earliest filing date + 20 years= Anticipated Expiry date 
Earliest filing date + (PTA or PTE if any) + 20 years= Adjusted Expiry Date* 

Let us now go through some examples to better understand how terminal disclaimer will effect the life of a U.S. patent, along with effective PTA or PTE. 

Case Study 1

Filed on January 1st, 2000 is Patent A. 
The continuation of Patent A is Patent B. 
Patent B was issued with a terminal disclaimer over Patent A. 

How Terminal disclaimer effects life of a U.S. patent

Case Study 2

Patent A is filed on January 1, 2002 
Patent B is a continuation of Patent A 
Terminal disclaimer filed in patent B against patent A 

How Terminal disclaimer effects life of a U.S. patent

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