What are the key differences between pre-AIA 35 U.S.C. 102(a), (b), and (e)?

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.

Pre-AIA 35 U.S.C. 102 subsections (a), (b), and (e) each define different types of prior art. According to MPEP 2139.02:

• 35 U.S.C. 102(a) covers knowledge or use by others in the U.S., or patents or printed publications anywhere, before the invention by the applicant.
• 35 U.S.C. 102(b) relates to public use or sale in the U.S., or patents or printed publications anywhere, more than one year before the application date.
• 35 U.S.C. 102(e) pertains to earlier-filed U.S. patent applications that are published or granted as patents.

Understanding these differences is crucial for patent examiners when evaluating prior art and determining patentability under the pre-AIA system. Each subsection has its own specific criteria and time frame for what qualifies as prior art.