What triggers an order for inter partes reexamination?

An order for inter partes reexamination is triggered when the Director finds that a substantial new question of patentability (SNQ) affecting a claim of a patent is raised, or that there is a reasonable likelihood that the requester would prevail (RLP) with respect to at least one of the claims challenged in the request.

As stated in MPEP 2646:

For a request filed prior to September 16, 2011: “If, in a determination made under section 312(a), the Director finds that a substantial new question of patentability affecting a claim of a patent is raised, the determination shall include an order for inter partes reexamination of the patent for resolution of the question.”

For a request filed between September 16, 2011 and September 15, 2012: “If, in a determination made under section 312(a), the Director finds that it has been shown that there is a reasonable likelihood that the requester would prevail with respect to at least 1 of the claims challenged in the request, the determination shall include an order for inter partes reexamination of the patent for resolution of the question.”

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Topics: MPEP 2600 - Optional Inter Partes Reexamination, MPEP 2646 - Decision Ordering Reexamination, Patent Law, Patent Procedure
Tags: inter partes reexamination, patent claims, Reasonable Likelihood Of Prevailing, substantial new question of patentability