(Clarification: This post analyzes patent reexaminations of a subject patent that claims the benefit of an earlier filed CIP and/or provisional application for priority purposes.  In such circumstances, intervening art presenting a Substantial New Question of patentability (SNQ) may be applied calling into question these priorty dates.  In such unique circumstances, enablement and written description issues pertaining to the originally issued patent claims will be considered by the USPTO for the purpose of detemining whether or not the priority claim is properly supported.  Of course, such an analysis of original patent claims is not performed outside of these limited circumstances). 

According the MPEP §§ 2258 and 2658, the USPTO during a reexamination proceeding will not consider 35 U.S.C. § 112, 1st paragraph issues with respect to the reexamination of original patent claims. It will, however, consider such issues where new or amended claims are presented or where any part of the disclosure is amended.

Nevertheless, where the patent subject to reexamination has claimed the benefit of the filing date of an earlier filed U.S. or foreign patent application, reexamination proceedings may be based on intervening patents or printed publications where the patent claims under reexamination may be entitled only to the actual filing date of the patent.

But can this strategy be used as a “back door” attack on the original patent claims’ compliance with 35 U.S.C. § 112, 1st paragraph where the patent for which reexamination is sought is a continuation or divisional patent?

Do the examiners in the Central Reexamination Unit have to make a determination of original continuation or divisional patent claims’ compliance with 35 U.S.C. § 112, 1st paragraph when assessing whether the parent application or patent complies with 35 U.S.C. § 112, 1st paragraph?

Suppose that the original patent’s prosecution history includes no intervening prior art. In such circumstance, the original examiner presumably made no affirmative determination as to the right of priority. Further assume that the patents or printed publications included in the reexamination request are non-cumulative with respect to the prior art of record in the original patent’s file history and raise a substantial new question of patentability against the original patent claims, if these claims are not entitled to the filing date of the earlier filed applications.

In accordance with the MPEP §2258 (I)(C), reexamination can be ordered under these facts, even though the effect will be to assess whether the original patent claims have adequate written description support and are full enabled.

The patent owner will likely presents arguments and evidence during reexamination that the parent applications provide adequate support for the original patent claims rather than amending or cancelling claims, or that the right to priority was determined in the original prosecution. (For an example of this issue where priority was assessed in the original prosecution see Reexamination Control No. 95/000,312 (discussing the Aotake reference)).

Advisedly, a third party requester should consider using inter partes reexamination rather than ex parte reexamination in order to fully participate in the proceedings. It is highly likely that the third party will need to rely on expert declaration evidence to rebut the patent owner’s showings as to why the original patent claims are entitled to an earlier filing date to antedate the intervening prior patents or printed publications.