How does the “described” requirement differ between AIA and pre-AIA patent law?

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 MPEP clarifies that the “described” requirement remains essentially unchanged between pre-AIA and AIA patent law. It states: “The Office does not view the AIA as changing the extent to which a claimed invention must be described for a prior art document to anticipate the claimed invention under 35 U.S.C. 102.” This means that the standards for determining whether a prior art document sufficiently describes an invention to qualify as anticipatory prior art are consistent between the two regimes.