How does the exception to the prior art rule affect patent litigation?

The exception to the prior art rule, as described in MPEP 2124, can have significant implications in patent litigation. This exception allows for the use of post-filing date evidence in certain circumstances, which can affect arguments related to enablement, written description, and the state of the art.

For example, the Federal Circuit case Amgen Inc. v. Sanofi (2017) illustrates this point:

Post-effective-filing-date evidence could be relied upon to show that patent failed to disclose a representative number of species of a claimed genus, and to show that patentees may have engaged in undue experimentation to enable the full scope of the claims before the effective filing date.

However, it’s crucial to note that while such evidence can be used to challenge the sufficiency of disclosure or enablement, it cannot be used to determine whether the application met the requirements of 35 U.S.C. 112(a) at the time of filing. This nuanced application of later evidence can significantly impact the strategies employed in patent litigation.

To learn more:

Topics: MPEP 2100 - Patentability, MPEP 2124 - Exception To The Rule That The Reference Must Be Prior Art, Patent Law, Patent Procedure
Tags: Enablement, Patent Litigation, Post-Filing Date Evidence, Written Description