Is the date of conception or reduction to practice relevant for determining the pre-AIA 35 U.S.C. 102(e) reference date?

No, the date of conception or reduction to practice is not relevant for determining the pre-AIA 35 U.S.C. 102(e) reference date. The MPEP clearly states:

“When the cases are not in interference, the effective date of the reference as prior art is its filing date in the United States (which will include certain international filing dates), as stated in pre-AIA 35 U.S.C. 102(e). The date that the prior art subject matter was conceived or reduced to practice is of no importance when pre-AIA 35 U.S.C. 102(g) is not at issue.”

Key points to remember:

  • The pre-AIA 35 U.S.C. 102(e) reference date is based on the filing date, not the date of conception or reduction to practice.
  • This applies to U.S. patents and certain international applications with a U.S. filing date.
  • The date of conception or reduction to practice only becomes relevant in interference proceedings or when pre-AIA 35 U.S.C. 102(g) is at issue.

This principle was affirmed in the case of Sun Studs, Inc. v. ATA Equip. Leasing, Inc., where the court held that when pre-AIA 35 U.S.C. 102(e) applies but not pre-AIA 35 U.S.C. 102(g), the filing date of the prior art patent is the earliest date that can be used to reject or invalidate claims.

To learn more:

Topics: MPEP 2100 - Patentability, MPEP 2136.03 - Critical Reference Date, Patent Law, Patent Procedure
Tags: Conception, Patent Prior Art, Pre-Aia 35 U.S.C. 102(E), reduction to practice