What happens if a negative limitation lacks support in the original disclosure?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

If a negative limitation lacks support in the original disclosure, it can lead to rejection of the claim. According to MPEP 2173.05(i):

“Any claim containing a negative limitation which does not have basis in the original disclosure should be rejected under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, as failing to comply with the written description requirement.”

However, the MPEP also notes that the mere absence of a positive recitation is not always sufficient to establish a prima facie case for lack of descriptive support. The Novartis Pharms. Corp. v. Accord Healthcare, Inc. case clarified that while silence generally won’t suffice to support a negative limitation, there may be circumstances where a skilled artisan would understand a negative limitation to necessarily be present in a disclosure.

For a more detailed discussion on this topic, refer to MPEP § 2163 – § 2163.07(b), which covers the written description requirement of 35 U.S.C. 112(a).