What triggers an order for inter partes reexamination?

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.

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.”