Can a reexamination proceeding itself be involved in an interference?

No, a reexamination proceeding itself cannot be involved in an interference proceeding. The MPEP clearly states: “Although a patent being reexamined via a reexamination proceeding may become involved in an interference proceeding, the reexamination proceeding itself can never be involved in an interference proceeding.

This is based on the language of 35 U.S.C. 135(a), which specifies that interferences can only be declared between applications or between an application and an unexpired patent. The MPEP explains: “The reexamination proceeding is neither an application nor a patent.”

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Topics: MPEP 2200 - Citation Of Prior Art And Ex Parte Reexamination Of Patents, MPEP 2284 - Copending Ex Parte Reexamination And Interference Proceedings, Patent Law, Patent Procedure
Tags: interference, patent law, USPTO procedures