How does inter partes reexamination differ from ex parte reexamination?
Inter partes reexamination differs from ex parte reexamination in several procedural aspects, but not in the substance considered. The MPEP states:
“Inter partes reexamination differs from ex parte reexamination in matters of procedure, such as when the third party requester can participate, the types of Office actions and the timing of issuance of the Office actions, and the requirement for identification of the real party in interest. Inter partes reexamination also differs from ex parte reexamination in the estoppel effect it provides as to the third party requesters and when the initiation of a reexamination is prohibited.”
However, the substantive examination is the same for both types of reexamination, focusing on prior art patents, printed publications, and compliance with 35 U.S.C. 112 for new or amended claims.
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