What is the critical reference date for pre-AIA 35 U.S.C. 102(e) prior art?

The critical reference date for pre-AIA 35 U.S.C. 102(e) prior art is an important concept in determining whether a reference qualifies as prior art under this section. While the MPEP excerpt provided doesn’t give a specific definition, it refers to MPEP § 2136.03 for more information:

“see MPEP § 2136.03 regarding critical reference date of pre‑AIA 35 U.S.C. 102(e) prior art”

Generally, the critical reference date for a U.S. patent or U.S. patent application publication under pre-AIA 35 U.S.C. 102(e) is the earliest effective U.S. filing date. This could be:

• The actual filing date of the U.S. application
• The filing date of a prior application if the reference is entitled to claim the benefit of an earlier filing date under 35 U.S.C. 120, 121, or 365(c)

For a more detailed explanation, please refer to MPEP § 2136.03.

To learn more:

• critical reference date
• pre-AIA 35 U.S.C. 102(e)
• prior art
• effective filing date