What is the main difference between AIA 35 U.S.C. 103 and pre-AIA 35 U.S.C. 103?

The most significant difference between AIA 35 U.S.C. 103 and pre-AIA 35 U.S.C. 103(a) is the timing of the obviousness determination. As stated in the MPEP:

AIA 35 U.S.C. 103 determines obviousness before the effective filing date of the claimed invention, rather than as of the time that the claimed invention was made.

This change primarily affects cases where there is evidence of an invention date prior to the effective filing date, which is typically presented through an affidavit or declaration under 37 CFR 1.131.

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Topics: MPEP 2100 - Patentability, MPEP 2158 - Aia 35 U.S.C. 103, Patent Law, Patent Procedure
Tags: AIA, effective filing date, Invention Date, Obviousness