Can previously considered art raise a substantial new question of patentability?

Yes, previously considered art can raise a substantial new question of patentability under certain circumstances. The MPEP 2216 clarifies:

“The substantial new question of patentability may be based on art previously considered by the Office if the reference is presented in a new light or a different way that escaped review during earlier examination.”

This provision was introduced by the Patent and Trademark Office Authorization Act of 2002, which allows for a substantial new question to be raised based on “old art” if it is presented in a new context or with a new interpretation. However, simply asking the Office to reconsider old art based on changes in legal standards (such as the KSR decision on obviousness) without presenting the art in a new light is not sufficient to raise a substantial new question of patentability.

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Topics: MPEP 2200 - Citation Of Prior Art And Ex Parte Reexamination Of Patents, MPEP 2216 - Substantial New Question Of Patentability, Patent Law, Patent Procedure
Tags: ex parte reexamination, patent examination, Substantial New Question