Chapter §21.05 Reexamination

• Jurisdiction: United States

§21.05 Reexamination

[A] Overview

Reexamination is a much newer administrative procedure in the U.S. patent system than reissue, having been established by legislation enacted in 1980.²⁰⁵ Reexamination's purpose was to provide a lower-cost alternative to federal court litigation in which to resolve certain questions of validity. Congress was influenced by studies showing that in the 1950s and 1960s, a large portion of the U.S. patents adjudicated invalid by federal courts were invalidated based on newly discovered prior art that had never been considered by the USPTO.²⁰⁶ Reexamination was seen as creating a relatively low-cost method of obtaining a USPTO examination on this newly discovered prior art. Reexamination represented, if not a copy of, at least the closest parallel in U.S. practice to the well-regarded post-grant opposition procedure of the European patent system.²⁰⁷

In practice, reexamination did not prove to be the panacea its proponents hoped for. The reexamination system was criticized as biased in favor of patent owners because of the extremely limited opportunities for third-party participation. Responding to these and other concerns, Congress as part of the American Inventors Protection Act of 1999 enacted a second, inter partes form of reexamination (renaming the original form ex parte reexamination). Although it offered greater participation for third parties, inter partes reexamination suffered from its own shortcomings in terms of a severe estoppel provision and procedural delays.²⁰⁸ In the America Invents Act of 2011, Congress phased out inter partes reexamination and replaced it with a new proceeding called "inter partes review" (eff. Sept. 16, 2012).²⁰⁹

Both ex parte and inter partes reexamination are detailed below. The statutes governing ex parte reexamination are found at 35 U.S.C. §§301–307 and continue in effect post-AIA. The statutes dealing with inter partes reexamination are found at 35 U.S.C. §§311–318 (2006) and are no longer in effect after September 16, 2012. In order to initiate either type of reexamination, the USPTO must be convinced that a "substantial new question of patentability"²¹⁰ arises from the prior art on which the request is based, as discussed below.

If a substantial new question of patentability exists, the USPTO will issue an order for reexamination.²¹¹ The reexamination of a patent proceeds in essentially the same manner as an original examination.²¹² Reexaminations are decided in the first instance by individual examiners, as in the examination of original applications.

Importantly, the presumption of validity that applies to an issued patent under 35 U.S.C. §282 is no longer applicable once a patent is in reexamination; in rejecting claims during reexamination the USPTO examiner is not required to satisfy the rigorous "clear and convincing" standard that applies in federal court litigation challenging the validity of issued patents.²¹³ Moreover, the USPTO will interpret the claims of the patent to be reexamined under the "broadest reasonable construction" standard,²¹⁴ which may result in a broader scope being assigned than would be the case in a federal district court validity challenge.²¹⁵

At the completion of either type of reexamination proceeding, the USPTO will issue a "Reexamination Certificate" that becomes part of the official patent document. The certificate will operate to (1) cancel any claim of the issued patent that is determined to be unpatentable, (2) confirm any claim of the issued patent that is determined to be patentable, and/or (3) incorporate into the issued patent any proposed amended claims or new claims that have been determined to be patentable.²¹⁶

Although confirmation of the patentability of reexamined patent claims may impress a jury by seemingly imbuing the patent with a "gold plated" aura, as a matter of law such confirmation does not confer on the reexamined patent a "super" or heightened presumption of validity. The reexamined claims may still be invalidated in federal court litigation even though they survived and were confirmed in reexamination. Nor does reexamination confirmation eviscerate any genuine issues of material fact underlying the question of validity. In its January 2018 decision in Exmark Mfg. Co. Inc. v. Briggs & Stratton Power Prod. Grp., LLC,²¹⁷ the Federal Circuit vacated a district court's summary judgment of no invalidity of a patent's claim 1 for anticipation or obviousness, apparently based solely on the fact that claim 1 had survived multiple reexaminations involving the same prior art.²¹⁸ In so doing the Circuit held that

a reexamination confirming patentability of a patent claim alone is not determinative of whether a genuine issue of fact precludes summary judgment of no invalidity. Surviving a reexamination does not warrant ipso facto summary judgment that a patent is not invalid. Holding otherwise would improperly give complete deference and preclusive effect to the PTO's patentability determination, foreclosing challenges to patent validity in district court based on the same prior art. ²¹⁹

[B] Ex Parte Reexamination

[1] Who Can Request

The ex parte reexamination procedure, the "older" form of reexamination, is governed by 35 U.S.C. §§301–307 and continues to be available post-America Invents Act of 2011. Although the name "ex parte" might suggest otherwise, this form of reexamination can be requested by anyone, not just the patent owner.²²⁰ Even the Director of the USPTO has requested reexamination of patents issued by his own agency.²²¹ When someone other than the patent owner requests that a patent be reexamined, that person or entity is generally referred to as the "third-party requester." A third-party requester may be anonymous.²²²

The ex parte nature of this form of reexamination reflects the very limited opportunities for participation by the third-party requester after it files the request for reexamination. If the USPTO orders reexamination, the patent owner will be permitted to file a responsive statement, which may include a proposed amendment to his claims, or new claims.²²³ The third-party requester will receive a copy of this statement and can file a response to it.²²⁴ From that point on, however, the reexamination proceeds much like the initial examination of an original application; the prosecution is conducted entirely between the patent owner and the USPTO, and the administrative records are maintained in secrecy (until application publication or patent issuance).²²⁵

It is commonly thought that because it has so little opportunity to participate, a third party (who is often in the position of accused or potential infringer of the patent) should request ex parte reexamination only if it has "dead-on" prior art that is virtually sure to invalidate the claims. If the third party's attempt does not succeed and the reexamination certificate confirms the patentability of all the claims, the patent may take on a "gold-plated" hue to judges and juries who will understand that the USPTO has twice confirmed its validity. It is likely that post-AIA, third parties will far less often seek ex parte reexamination and instead will petition for inter partes or post-grant review of patents.

[2] Statutory Grounds for Reexamination

Sections 301 and 302 of the Patent Act significantly limit the grounds on which reexamination of a patent can be sought. A request for reexamination can be based only on prior art consisting of patents or printed publications,²²⁶ which means that patentability can be challenged in reexamination only under an appropriate portion of 35 U.S.C. §102 (lack of novelty) or under 35 U.S.C. §103 (obviousness).²²⁷ Reexamination cannot be sought to challenge inventorship, or to assert non-eligibility or lack of utility under 35 U.S.C. §101, or nonenablement or noncompliance with the written description of the invention requirement under 35 U.S.C. §112(a). Under pre-AIA rules, reexamination could not be used to inquire into potentially invalidating on sale or public use bars under 35 U.S.C. §102(b) (2006).

[3] Substantial New Question of Patentability

Before it will issue an order for reexamination, the USPTO must find that the request raises a "substantial new question of patentability."²²⁸ The purpose of incorporating this threshold requirement into the statute was to prevent abuse of the system and harassment of patentees by third parties making multiple requests for reexamination without a substantial basis.²²⁹ The standard applied by the USPTO for identifying a substantial new question sufficient to support an order for reexamination is that the prior art identified in the request would be considered "important" in deciding patentability to a reasonable examiner, but need not necessarily render the claims prima facie unpatentable.²³⁰

Can a substantial new question of patentability be based on prior art that was known to the USPTO during examination of the original application? The Federal Circuit's 1997 decision in In re Portola Packaging, Inc.²³¹ temporarily eliminated this possibility.²³² The Portola court held that the agency could not make rejections in reexamination based on any combination of prior art references that were previously considered by the USPTO in the prosecution of the original application, even where the claims had been amended during reexamination such that they were not the same as those considered in the original examination.

The facts of Portola are these: During examination of the original application, a number of prior art references were cited by the examiner, including the "Hunter" patent and the "Faulstich" patent. Specifically, the examiner rejected certain claims of the original application as anticipated under §102 by Hunter, and other claims as obvious under §103 in view of Faulstich in combination with two other references.²³³ The applicant amended the claims in response to the rejections, added new claims, and was ultimately granted a...