Terminal disclaimer

A terminal disclaimer in patent law is explained by section 1490 of the Manual of Patent Examining Procedure:

“

A disclaimer is a statement filed by an owner ... of a patent or of a patent to be granted, in which said owner relinquishes certain legal rights to the patent. ... [A] terminal disclaimer under 37 CFR 1.321(a) and (b) [is] used to disclaim or dedicate a portion or the entire term of all of the claims of a patent.

”

The purpose of a terminal disclaimer is to extend the lifetime of a patent:

“

First, we note that an [obviousness-type double patenting] ODP determination depends on an assessment of obviousness, i.e., whether the claims of a later-expiring patent would have been obvious over the claims of an earlier-expiring patent owned by the same party. If so, absent a terminal disclaimer, the later-expiring claims are invalid. Application of that determination requires determining which is the later-expiring patent, which is why the date when PTA or PTE is applied matters.

”

In re Cellect, LLC, 81 F.4th 1216, 1226 (Fed. Cir. 2023).

As explained further the Federal Circuit:

“

By disclaiming that portion of the second patent which would extend beyond the expiration of the first, the patentee gives up any extension of patent protection that might have resulted. Braithwaite, 379 F.2d at 601, 154 USPQ at 35. Initial patent applications involved in the present case were filed in England, and later, corresponding applications were filed in the United States. In October, 1962, an omnibus continuation-in-part application containing over 450 working examples was filed in the United States. This application eventually issued as the '911 patent, which expired on November 26, 1991.

”

Ortho Pharm. Corp. v. Smith, 959 F.2d 936, 940-41 (Fed. Cir. 1992).