Can a negative limitation be used to overcome a prior art rejection?

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.

Yes, a negative limitation can be used to overcome a prior art rejection, provided it meets certain criteria. According to MPEP 2173.05(i):

“The mere absence of a positive recitation is not basis for an exclusion. 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.”

To use a negative limitation effectively:

• Ensure it has proper support in the original disclosure
• Demonstrate that it distinguishes the claimed invention from the prior art
• Show that it does not introduce new matter

For example, if a prior art reference teaches a device with a specific component, and your invention specifically excludes that component, you could potentially overcome the rejection by adding a negative limitation. However, this approach should be used judiciously and only when there is clear support in the original disclosure.