Post-Grant Patent Proceedings

Supplemental Examination

The AIA's inequitable conduct shield — correcting the record before litigation.

Quick Answer

35 U.S.C. § 257 lets patent owners submit any information to the USPTO for reconsideration. If the request is filed before any inequitable conduct lawsuit, the resulting supplemental examination certificate permanently shields the patent from unenforceability claims based on that information.

Purpose

Why Supplemental Examination Exists

Before the AIA, a patent owner who discovered undisclosed prior art after issuance had limited options: file a reissue application (complex, triggers prosecution history estoppel issues), file an ex parte reexamination (may raise SNQ, starts reexamination), or do nothing (risk inequitable conduct defense in litigation). The Therasense, Inc. v. Becton, Dickinson & Co. (Fed. Cir. 2011 en banc) standard raised the bar for inequitable conduct — requiring but-for materiality and specific intent to deceive — but did not eliminate the threat.

35 U.S.C. § 257 created a new proactive option: a patent owner can voluntarily bring any relevant information to the USPTO's attention, and if the USPTO considers it, the patent is immunized from inequitable conduct claims based on that information. It's essentially a prosecutorial "clean slate" for pre-identified issues.

35 U.S.C. § 257(c)(1)

"A patent shall not be held unenforceable on the basis of conduct relating to information that had been considered, reconsidered, or corrected during a supplemental examination of the patent, unless the allegation of conduct relating to such information is … based upon information submitted in a fraudulent manner."

Process

Step-by-Step: Supplemental Examination

File supplemental examination request (Form PTO/SB/440)

Up to 12 items of information may be presented per request. Each item must include the information itself and an explanation of its relevance. The request is filed by the patent owner (not a third party) and cannot be filed after a civil action for inequitable conduct is pending.

Filing fee: $2,000 (large entity), $1,000 (small), $500 (micro). Additional $4,500/$2,250/$1,125 if reexamination ordered.

USPTO determines whether SNQ is raised (within 3 months)

The USPTO reviews each item and determines whether any item raises a 'substantial new question of patentability' — the same SNQ standard as ex parte reexamination. If no SNQ on any item: the USPTO issues a supplemental examination certificate. Certificate = inequitable conduct shield.

No SNQ → Supplemental examination certificate issued

If no item raises an SNQ, a supplemental examination certificate issues. The patent is confirmed as fully examined with respect to those items. The inequitable conduct shield is established. No further examination occurs — the patent terms are unchanged.

SNQ found → Ex parte reexamination ordered

If any item raises an SNQ, the USPTO orders an ex parte reexamination of the claims for which the SNQ applies. The proceeding follows standard ex parte reexamination rules — the patent owner has full participation rights (responses, amendments, interviews). The examiner may reject claims, patent owner responds.

Ex parte reexamination concludes → Certificate issued

Reexamination ends with a reexamination certificate confirming, canceling, or amending claims. If claims survive, the inequitable conduct shield applies. If claims are canceled, the shield is moot for those claims. The shield still applies to surviving claims.

Comparison

Supplemental Examination vs. Other Post-Grant Options

	Supplemental Exam	Ex Parte Reexam	Reissue
Who can file	Patent owner only	Anyone (including third parties)	Patent owner only
Primary purpose	Inequitable conduct shield	Challenge claim validity	Correct errors, broaden/narrow claims
Grounds	Any relevant information	§§ 102/103 prior art only	Error or claim correction
Estoppel?	None on patent owner	None (ex parte)	Intervening rights for broadened claims
Prosecution history estoppel?	Only if reexam ordered and amendments made	Yes — amendments create estoppel	Yes — amendments create estoppel
Claim broadening?	No	No	Yes — within 2 years of issuance
Timing bar	Must file before inequitable conduct civil action	Any time; director-ordered within 2 years	2 years for broadening claims
Inequitable conduct shield?	Yes — primary purpose	No	No

FAQ

What is supplemental examination?

Supplemental examination is a post-grant USPTO proceeding under 35 U.S.C. § 257 (added by the AIA, effective September 16, 2012) that allows a patent owner to request that the USPTO consider, reconsider, or correct information believed to be relevant to the patent. Its primary legal effect: a patent cannot be held unenforceable based on conduct or information that was considered, reconsidered, or corrected during supplemental examination — provided the supplemental examination request was filed before a civil action for inequitable conduct was brought.

When should a patent owner file for supplemental examination?

Before licensing or litigating — especially when: (1) there is undisclosed prior art that may have been material to the original prosecution; (2) an IDS was submitted but a reference was accidentally omitted; (3) inventors or prosecution counsel did not disclose third-party publications or prior commercial activity known to them; (4) there's concern that a reference disclosed in foreign counterparts was not submitted to the USPTO. The supplemental examination request must be filed before a civil action for inequitable conduct is filed — once a complaint is filed, the proceeding cannot eliminate existing inequitable conduct claims.

What can supplemental examination correct?

Any information 'believed to be relevant to the patent' — including prior art not submitted during prosecution, prior art submitted but arguably not adequately flagged, incorrect statements in the specification or IDS, prior public use or sale not disclosed, and other information potentially material under the materiality standard of 37 C.F.R. § 1.56. The scope is intentionally broad — the patent owner describes the information and explains its relevance.

What happens after a supplemental examination request is filed?

The USPTO has 3 months to determine whether the information raises a substantial new question of patentability (SNQ). If no SNQ: the patent owner receives a supplemental examination certificate — the record is considered corrected for inequitable conduct purposes. If SNQ: the USPTO orders ex parte reexamination of the identified claims. The reexamination proceeds like a standard ex parte reexamination — the patent owner can respond to any rejections. If claims survive, an ex parte reexamination certificate issues.

Are there limitations on the inequitable conduct shield from supplemental examination?

Yes — the shield has a critical exception: if the information submitted contains or is based on a fraudulent statement (submitted as part of a scheme to defraud the USPTO), the inequitable conduct shield does not apply. Additionally, the shield doesn't apply if a civil action alleging inequitable conduct was already filed before the supplemental examination request. The shield also doesn't eliminate existing criminal fraud liability or § 285 exceptional case fees based on non-inequitable-conduct conduct.