What is the critical reference date for a U.S. patent or patent application publication?

The critical reference date for a U.S. patent or patent application publication under 35 U.S.C. 102(e) as amended by the American Inventors Protection Act of 1999 (AIPA) (pre-AIA) is the earliest effective U.S. filing date. This is stated in MPEP 2136.03:

“The critical reference date of a U.S. patent or patent application publication under pre-AIA 35 U.S.C. 102(e) is the earliest effective U.S. filing date.”

This means that when considering a U.S. patent or patent application publication as prior art, examiners must look at the earliest effective U.S. filing date to determine its applicability as a reference.

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Topics: MPEP 2100 - Patentability, MPEP 2136.03 - Critical Reference Date, Patent Law, Patent Procedure
Tags: 35 U.S.C. 102(E), aipa, Critical Reference Date, effective filing date, patent application publication, U.S. Patent