Reissue v. Supplemental Examination

By Naphtali Y. Matlis

The Leahy-Smith America Invents Act of 2011 ("AIA") provides several ways for patent owners to amend and correct issued patents, including reissue and supplemental examinationReissue was an option under the previous patent law, but the AIA made a significant change to the rules governing when and how a reissue may be sought.  Supplemental examination is an entirely new avenue for patent owners to identify and correct potential problems in issued patents.  Problems in issued patents may include inoperable or ineffective claims, failure to disclose prior art references, incorrect inventorship, and other issues that may affect the validity or enforceability of the patent claims.  Of these problems, those related to or caused by inequitable conduct are of special interest due to the recent decision by the Court of Appeals for the Federal Circuit in Therasense, Inc. v. Becton, Dickinson & Co.1  This article explains the holding of Therasense, and how Therasense impacts a patent owner’s decision in choosing reissue or supplemental examination to either change the claim scope or correct the prosecution history record.

Inequitable Conduct After Therasense

Inequitable conduct is a defense to an allegation of patent infringement.  The contention is that the patent in question is not valid because the patent applicant breached their duty of candor and good faith to the U.S. Patent and Trademark Office while applying for a patent.  Breaches of duty of candor can include:

(a) failure to submit material prior art known by the applicant;

(b) failure to explain references in a foreign language or submit pre-existing full or partial translations of the references;

(c) misstatements of fact, including misstatements in affidavits concerning patentability; and

(d) misdescription of inventorship (authorship).

Failure to submit material prior art known by the applicant is only a breach of the duty of candor and good faith when the prior art is “material.” The Court of Appeals for the Federal Circuit, in the en banc re-hearing of Therasense, held that “as a general matter, the materiality [of prior art] required to establish inequitable conduct is but-for materiality” (emphasis added). In other words, if an applicant does not disclose information about prior art, that information is material for purposes of inequitable conduct only if, had the PTO been aware of the undisclosed prior art, it would not have allowed (not necessarily rejected) a claim in the patent.  The court went on to say that although reissue cannot cure inequitable conduct per se, the fact that the PTO was made aware of, and considered, a previously omitted prior art reference during reissue and nonetheless issued the patent indicates that the previously omitted prior art reference was not “but-for” material.

Changes To Reissue

The AIA amended 35 U.S.C. § 251 to remove the language "without any deceptive intention" from the law governing reissue, opening the way for a much wider range of errors to be corrected through reissue under section 251(a), which now reads as follows:

(a) In General. – Whenever any patent is, through error deemed wholly or partly inoperative or invalid, by reason of a defective specification or drawing, or by reason of the patentee claiming more or less than he had a right to claim in the patent, the Director shall, on surrender of such patent and the payment of the fee required by law, reissue the patent for the invention disclosed in the original patent, and in accordance with new and amended application, for the unexpired part of the term of the original patent. No new matter shall be introduced into the application for reissue.

By removing “without any deceptive intention” from section 251(a), the AIA, in conjunction with Therasense, arguably opens the door for patent owners to address questions of inequitable conduct via reissue.  A patent owner may now admit to a defect in a patent, such a defect potentially including an omitted prior art reference.  By submitting the reference for consideration during reissue, a patent owner may address the issue of but-for materiality.  Since the reference is considered during reissue, the previous omission is no longer but-for material within the meaning of the Therasense holding if the claim(s) in question survive the reissue process.

It should be noted, however, that Therasense addresses only the question of materiality of intentionally omitted prior art.  Inequitable conduct related to failure to explain references and mis-statements of fact is not discussed by the Federal Circuit as something that can be addressed or otherwise cured in a reissue.  Although the words “without deceptive intent” have been removed from the law governing reissue, those aspects of inequitable conduct have yet to be tested in the courts or otherwise interpreted and evaluated in light of the new law.

Additionally, reissue allows for the addition of narrower, dependent claims.  The Federal Circuit, in its decision in the In re Tanaka decision,2 stated that the addition of narrower, dependent claims in a patent reissue is an “error” as contemplated by section 251(a).  Reissue therefore also provides a way for patent owners to add new dependent claims that were previously omitted.

 Supplemental Examination

Under 35 U.S.C. § 257, "[a] patent owner may request supplemental examination of a patent in the Office to consider, reconsider, or correct information believed to be relevant to the patent." Within three months of receiving such a supplemental examination request, the PTO must conduct the supplemental examination and issue a certificate indicating whether the information presented in that request "raises a substantial new question of patentability."3 If it is determined that the request raises a substantial new question of patentability, an ex parte reexamination will be conducted to address each new question of patentability identified in the supplemental examination.4

The AIA does not specify or limit the type of information that may be corrected through this supplemental examination procedure. The only requirement is that the information must be “believed to be relevant to the patent.”5 Furthermore, the resulting reexamination is not limited to patents and printed publications as required under the ex parte reexamination rules of chapter 30.6 Supplemental examination can therefore be used to address issues relating to 35 U.S.C. §§ 101, 112, or inequitable conduct.

A particular advantage of the supplemental examination procedure is that the AIA specifically states that a patent cannot be held unenforceable based upon information that was "considered, reconsidered, or corrected during a supplemental examination of the patent."7  The supplemental examination therefore arguably provides a process for curing a potentially broader range of inequitable conduct, as well as issues related to enablement, written description, patentable subject matter, clarity of claim terms, and a host of other potential barriers to patent enforceability.

Consider Supplemental Examination To Confirm, Reissue To Repair and Prepare

Although both reissue and supplemental examination provide avenues for effectively curing certain types of defects or problems in a patent, including pre-empting or otherwise resolving issues related to inequitable conduct, each has particular advantages and disadvantages making them particularly suitable in different situations.

Supplemental examination is expensive.8  Also, supplemental examination results in an ex parte reexamination in the event a supplemental examination request results in a substantial new question of patentability, which limits the patent owner's options.  The patent owner cannot stop an ex parte reexamination. Specifically, there is no option for a patent owner to file a Request For Continued Examination (RCE) after a “final” office action in a re-examination.  The only option after a “final” office action during reexamination is appeal, either to the BPAI or to the courts.  However, supplemental examination offers significant advantages over reissue.  Unlike reissue, a request for supplemental examination does not require a patent owner to admit a defect in the patent.  Also, unlike reissue, a decision on supplemental examination must be made within three months of request submission.  Furthermore, a request for supplemental examination that is determined to raise no substantial new questions of patentability ends with that determination.    Patent owners preparing to enforce their patent(s) may therefore opt to file a request for supplemental examination as an enforcement preparation technique.  If the patent owner is relatively certain that there are no problems with the patent and that there is no material prior art that has not yet been considered, they may wish to request supplemental examination on the expectation that supplemental examination will be denied / refused and the information considered in the supplemental examination request will be disqualified from later use by defendants seeking to render a the patent invalid or otherwise unenforceable.

However, a patent owner actually aware of a particular issue or defect in a patent is still served better by requesting reissue than supplemental examination.  Reissue is less costly than supplemental examination even if no re-examination results from supplemental examination, and also offers the advantage of making all patent prosecution options available to the patent owner, including an RCE in the event of a “final” office action.  Furthermore, failures to previously disclose material prior art, even if done with deceptive intent, may now arguably be cured by reissue, making it a viable option for addressing or correcting otherwise un-enforceable or inoperable claims and thereby avoiding invalidation of the whole patent.  Further, a reissue application can be abandoned, the patent will still have the original claims.  However, the reissue process can be slow compared to ex parte reexamination.

The choice of whether to pursue supplemental examination or reissue is therefore one that must balance concerns of cost and concerns about the patent itself.  The advantages of speedy resolution, reference disqualification, and of not having to admit to any defect in the patent conferred by the supplemental examination process come at significant financial cost and also at the price of being locked into a re-examination proceeding should the supplemental examination request identify a substantial new question of patentability.  Additionally, the patent owner only has limited ability to direct the attention of the PTO to particular aspects of the patent. 

Reissue, while slower and predicated on the admission of a defect in the patent, gives the patent owner more flexibility and ability to make corrections and changes that the patent owner knows are necessary.   Both are powerful and versatile tools available to patent owners to help them prepare for patent enforcement by pre-empting or forestalling the affirmative defense of invalidating a patent on grounds inequitable conduct.

Also, a patent owner seeking to enforce a patent may, upon review, realize that one or more specific aspects of their invention, although discussed in the specification, are not explicitly claimed.  Adding those specific aspects in dependent claims as part of a pre-enforcement review and preparation is, because of the In re Tanaka ruling, now possible.  Ultimately, the choice of whether to pursue reissue or supplemental examination will be determined by the facts and specific situation of a patent owner.  Supplemental examination is tool to confirm that a patent is in good order for enforcement, whereas reissue is a way to affirmatively fix known deficiencies in a patent in preparation for enforcement.


  1. 99 U.S.P.Q.2d 1065 (Fed. Cir. 2011).
  2. 98 U.S.P.Q.2d 1331 (Fed. Cir. 2011).
  3. § 257(a).
  4. § 257(b).
  5. § 257(a).
  6. § 257(b).
  7. § 257(c)(1).
  8. See USPTO proposed fee schedule at http://www.uspto.gov/aia_implementation/fee_setting_-_ppac_hearing_attachment_1-table_of_patent_fee_changes_7feb12.pdf  and proposed rules in Fed. Reg., Vol. 77, No. 16, Jan. 25, 2012.