How does the AIA affect the effective filing date of subject matter in prior art?

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 America Invents Act (AIA) introduced changes to how the effective filing date of subject matter in prior art is determined. Under AIA 35 U.S.C. 102(d), the effective filing date for subject matter in a U.S. patent document can be:

• The actual filing date of the patent or application
• The filing date of the earliest application to which the patent or application is entitled to claim a right of priority or benefit

This means that the effective filing date can potentially be earlier than the actual filing date of the document, which is crucial for determining prior art status.