Inter Partes Reexamination

By Eugene T. Perez

(A) Getting Started and Procedure
(B) Estoppel
(C) Petitions

Compared to an ex parte reexamination procedure, an inter partes reexamination proceeding provides a third party requester (hereinafter referred to as “TPR”) with a greater opportunity to participate, while maintaining most of the features which make reexamination a desirable alternative to litigation in the Federal Courts.   For instance, in an inter partes reexamination proceeding, the third party requester may respond to all substantive responses filed by the patent owner and either appeal an unfavorable decision by the Board of Patent Appeals and Interferences (BPAI) up to the CAFC or have the right to participate in any appeal taken by the patent owner to the CAFC.

As a summary, inter partes reexamination benefits for a TPR include:

1. Significant third party participation in the proceeding from the filing of a request for reexamination, reexamination being ordered, Examiner’s action closing prosecution, Appeal to the Board of Appeals and the Federal Circuit to the time the Reexamination Certificate is issued.

2. As in ex parte reexamination proceedings, the patent owner has a continuing duty of disclosure to the USPTO under 37 C.F.R. § 1.56 and there is no presumption of validity of patents with respect to which inter partes reexamination has been ordered.

3. For the most part, a different (Primary) Examiner will handle the inter partes reexamination proceeding than did the Examiner who examined the application that matured in to the patent undergoing inter partes reexamination. This may be beneficial or it may not.

4. Once reexamination is ordered, it continues until a reexamination Certificate is issued and cannot be withdrawn.

5. Once reexamination is ordered, the patent under reexamination no longer enjoys a presumption of validity.

6. During reexamination, claims are given their broadest reasonable interpretation, making it easier to reject the claims in view of prior art.

7. Patent Owner amendment and/or arguments can create prosecution history estoppel.

8. Previously cited art in the patent can be relied upon in a request for reexamination.

9. Claims amendments during the proceeding may provide intervening rights to an infringer.

10. Admissions against interest, if they are clear, unmistakable and unequivocal, can be used against the patent owner, not by themselves, but in connection with patents and printed publications.

Inter partes reexamination drawbacks for a TPR include:

1. A third party Requester cannot prevent a patent owner from amending existing claims and/or adding claims of the same scope or narrower scope to make them stronger and still be infringed by the third party requester.

2. Three estoppel provisions have been established against third party Requesters.

3. Responses to Patent Owner submissions are limited in time to 30 days from date served on third party requester.

4. No review of this proceeding in a federal district court (just the BPAI and the Federal Circuit), which means you are limited on appeal to the record before the USPTO.

5. If patent owner files a broadening reissue, it cannot be merged with an inter partes reexamination proceeding.

(A) Getting Started and Procedure

The inter partes reexamination starts with the filing of a request for reexamination, wherein the request must set forth the facts relevant to the reexamination, primarily facts pertaining to the application of the new prior art to the claims for which reexamination is requested.  Typically, should the USPTO grant the inter partes reexamination, a first Office Action issues.  With certain timelines, the patent owner files a response to the Office Action and the TPR can respond to any response filed by the patent owner.

However, mistakes are made by both the patent owner and TPR during the course of the inter partes reexamination proceeding.  In fact, mistakes can be made at any stage of the inter partes reexamination proceeding (i.e., initial requirements for filing the request for inter partes reexamination all the way to appeal). 

Subsequent to the first Office Action and upon a determination by the patent examiner that the issues have been “clearly developed”, the Examiner may issue an Action Closing Prosecution (“ACP”) which severely limits further attempts by the patent owner to introduce any additional changes to the patent claims or evidence supporting patentability.1

After the ACP issues, the patent owner may once file written comments and/or present a proposed amendment to the claims within the time period set in the ACP.2  Normally, the ACP will set a period of 30 days or one month (whichever is longer) from the mailing date of the ACP. Where the patent owner files comments and/or a proposed amendment, the third party requester may once file comments responsive to the patent owner's submission within 30 days from the date of service of the patent owner’s submission on the third party requester.3

Upon issuance of the ACP, a Notice of Appeal (“NOA”) cannot be filed by either party at this point. After receiving any additional comments from the patent owner, and any additional optional comments from the third party requester, the patent examiner may then issue a “Right of Appeal Notice” (or “RAN”) which then allows either party to appeal the reexamination.4

37 C.F.R. §§ 1.949 and 1.951 and M.P.E.P. § 2672 set the standard for the patent owner’s option after an ACP issues.  As stated in 37 C.F.R. § 1.951(a) and M.P.E.P. § 2672, any amendment as proposed by the patent owner is governed by the strict criteria of 37 C.F.R. § 1.116 (“Rule 116”) as to whether or not such amendment should be admitted.  Rule 116, subsection (b)(1)-(3), allows entry of a proposed amendment only when:

  • (1) an amendment is made to cancel claims or to comply with any requirement of form expressly set forth in previous Office Action;
  • (2) an amendment presenting rejected claims in better form for consideration on appeal that may be admitted; or
  • (3) an amendment touching the merits of the application or patent under reexamination may be admitted based on a showing of good and sufficient reasons why the amendment is necessary and was not earlier presented.

Thus, the patent owner has limited options once the ACP issues.  Any substantive changes to the claims will likely result in the in the filed Amendment not being entered.

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(B) Estoppel

As mentioned, a significant disadvantage of inter partes reexamination is the requirement that a third-party is “es­topped” (i.e. precluded) from ever asserting at a later time in any civil action (under 28 U.S.C. 1338) or subsequent inter partes reexamination the invalidity of any claim on any ground the third-party raised, or could have raised, during the inter partes proceeding.5

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(C) Petitions

There are three types of petitions as provided for in 37 C.F.R. §§ 1.181-183 (“Rule 181 Petition”, etc.).  Each type of petition serves a different purpose.

  1. Rule 181 Petition
    Regarding a Rule 181 petition, there are two types: (1) a premature ACP invoking supervisory authority of the USPTO Director; and (2) denial of entry of amendments filed in response to an ACP.6 

    Regarding the first type of Rule 181 petition (a premature ACP invoking supervisory authority of the USPTO Director), a typical situation is where an ACP has issued, and then the patent owner files an amendment wherein the claims are amended to address the ground(s) of prior art rejection(s).  Thereafter, the RAN indicates whether or not the claim amendments are entered for purposes of appeal.  If the claim amendments are not entered, the patent owner may file a Rule 181 petition to request entry.  However, many of these petitions are dismissed.7

  2. Rule 183 Petition

    A Rule 183 petition can be used to waive a rule specific in 37 C.F.R.  It is worth nothing that as stated in M.P.E.P. § 2673.02, when a Rule 181 petition is filed, the USPTO encourages that a Rule 183 petition be also filed to request waiver of the prohibition of an extension of time for filing an appeal brief. In effect, the petitioner is requesting that the due date for filing the appeal brief be tolled.

    As an example of a rule to be waived, and as mentioned, a response to a first Office Action or to the ACP cannot exceed 50 pages in length (but excludes claims and references).8 Patent Owner appellant briefs are not to exceed 30 pages or 14,000 words.9  A Rule 183 petition can be filed to waive such page/word limits.

  3. Rule 182 Petition
    As the third type of petition, a Rule 182 petition is used for questions not specifically provided for.  For instance, a Rule 182 petition can used by the patent owner to reopen prosecution.  However, remember that this is a petition that needs a decision from the USPTO.  Further, simply filing the Petition does not toll the time period for filing a response to an outstanding Office Action.

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  1. 37 Code of Federal Regulations (“C.F.R.”) § 1.949.
  2. 37 C.F.R. § 1.951(a).
  3. 37 C.F.R. § 1.951(b).
  4. 37 C.F.R. § 1.953.            
  5. 37 C.F.R. § 1.907.
  6. Manual of Patent Examining Procedure (“M.P.E.P.”) § 2672(VI) and § 2673.02.
  7. See, e.g., Reexamination Control Nos. 95/000,010, 95/000,020, 95/000,025, 95/000,070 and 95/000,071.
  8. 37 C.F.R. § 1.943(b).
  9. 37 C.F.R. § 1.943(c).