How does the “time of invention” differ for AIA and pre-AIA applications in equivalence determinations?

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.

The “time of invention” consideration differs for AIA (America Invents Act) and pre-AIA applications in equivalence determinations:

• For AIA applications: The relevant time is “before the effective filing date of the claimed invention.”
• For pre-AIA applications: The relevant time is “at the time of the invention.”

MPEP 2183 notes: “For applications subject to the first inventor to file (FITF) provisions of the AIA, the relevant time is “before the effective filing date of the claimed invention”. For applications subject to pre-AIA 35 U.S.C. 102, the relevant time is “at the time of the invention”.” This distinction is crucial when considering prior art and determining equivalence in patent examination.