What is the significance of an affidavit or declaration under 37 CFR 1.131(a) in overcoming a pre-AIA 35 U.S.C. 102(e) 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.

An affidavit or declaration under 37 CFR 1.131(a) can be used to overcome a pre-AIA 35 U.S.C. 102(e) rejection by proving prior invention. However, it’s important to note that this method has limitations.

The MPEP states: “An affidavit or declaration under 37 CFR 1.131(a) can overcome a prior art rejection under pre‑AIA 35 U.S.C. 102(e) by proving invention of the claimed subject matter by the inventor or at least one joint inventor prior to the effective date of the reference relied upon in the rejection.“

However, there are restrictions on when this method can be used. The MPEP further clarifies: “When the claims of the reference U.S. patent or U.S. patent application publication and the application are directed to the same invention or are obvious variants, an affidavit or declaration under 37 CFR 1.131(a) is not an acceptable method of overcoming the rejection.“