Can post-filing date evidence be used to determine enablement or written description?

No, post-filing date evidence cannot be used to determine enablement or written description under 35 U.S.C. 112(a). The MPEP 2124 clearly states:

It is impermissible to use a later factual reference showing the state of the art existing after the effective filing date of the application to determine whether the application is enabled or described as required under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph.

This restriction ensures that the assessment of enablement and written description is based on the knowledge available at the time of filing, not on subsequent developments in the field.

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Topics: MPEP 2100 - Patentability, MPEP 2124 - Exception To The Rule That The Reference Must Be Prior Art, Patent Law, Patent Procedure
Tags: 35 u.s.c. 112(a), Enablement, Post-Filing Date Evidence, Written Description