37 CFR 1.945 - Response to Office action by patent owner in inter partes reexamination.
(a) The patent owner will be given at least thirty days to file a response to any Office action on the merits of the inter partes reexamination.
(b) Any supplemental response to the Office action will be entered only where the supplemental response is accompanied by a showing of sufficient cause why the supplemental response should be entered. The showing of sufficient cause must include:
(1) An explanation of how the requirements of § 1.111(a)(2)(i) are satisfied;
(2) An explanation of why the supplemental response was not presented together with the original response to the Office action; and
(3) A compelling reason to enter the supplemental response.