Ex Parte Reexamination

Ex parte reexamination (EPR) is a USPTO administrative proceeding in which the USPTO reexamines the patentability of one or more claims of an issued patent based on prior art patents or printed publications. LEGAL BASIS: 35 U.S.C. §§ 302–307 (enacted as part of the Patent Act of 1980); regulations at 37 C.F.R. §§ 1.510–1.570; AVAILABILITY: any person (including anonymous third parties — the request can be filed by a third party without identifying themselves; the USPTO rules permit anonymous filing) may file an EPR request at any time during the enforceable life of a patent; the patent owner can also request EPR of their own patent; COST: current USPTO fee for a third-party EPR request: $18,400 (small entity: $9,200; micro entity: $4,600) as of 2024; significantly less expensive than IPR ($20,000+ just for the filing fee, plus attorney fees of $50–200K); SCOPE: only §§ 102 (anticipation) and 103 (obviousness) grounds based on prior art PATENTS and PRINTED PUBLICATIONS are permitted; cannot raise § 101 (subject matter eligibility), § 112 (specification issues), or public use/on-sale bar (§ 102(b) events that are not documented in patents or publications); STATISTICS: the USPTO grants EPR requests on substantially new questions of patentability at approximately 90%+ rate; of those reexaminations, roughly 25–30% result in all claims cancelled; 65–70% result in amended or unchanged claims.

The threshold for ordering an EPR is whether the request raises a 'substantial new question of patentability' (SNQ). SNQ STANDARD: 35 U.S.C. § 303; a question of patentability is 'substantial' if there is a non-frivolous likelihood that the prior art raises a real and substantial question about the validity of at least one claim; SNQ means the question is new to the USPTO examination — either: (a) a reference not previously considered by the examiner; (b) a reference previously considered but now cited in a different way or combination; (c) a reference in a new combination not previously made; SUBSTANTIAL NEW vs. IPR'S REASONABLE LIKELIHOOD: SNQ is an EASIER standard than the IPR threshold of 'reasonable likelihood that the petitioner would prevail' (§ 314(a)); SNQ is approximately equivalent to 'reasonable likelihood' in practice, but historically was applied somewhat more liberally; WHAT RAISES SNQ: (1) a prior art patent that anticipates at least one claim (§ 102); (2) a combination of prior art references that would have made the claimed invention obvious (§ 103); (3) a reference that was considered by the examiner but only to reject a different claim or different claim limitation; WHAT DOES NOT RAISE SNQ: arguments already made and considered during prosecution with the same prior art in the same combination; REQUESTER STATEMENT: the EPR request must include: (1) a statement identifying each claim challenged; (2) a citation to each prior art patent/publication; (3) a detailed explanation of how each claim is anticipated or rendered obvious by the cited art (claim charts).

THE EPR PROCESS (third-party requester): (1) FILING: request filed under § 302; includes request form, prior art citations, claim charts, fee; (2) FILING ACKNOWLEDGMENT: USPTO acknowledges receipt; (3) SNQ DETERMINATION (within ~3 months): Director (in practice, the OPLA or a supervisor) determines whether a SNQ exists; if yes, reexamination ordered; if no, request denied — no appeal for third-party requester (patent owner can appeal denial); (4) ORDER FOR REEXAMINATION: notice published in Official Gazette; patent owner notified; prosecution opens; (5) PATENT OWNER'S RESPONSE: patent owner has 2 months (extendable) to: (a) respond to office actions; (b) amend claims to overcome prior art; (c) present arguments; third-party requester has ONE opportunity to submit comments on the patent owner's response, within 30 days — after that, the requester is locked out; (6) PATENT OWNER-ONLY PROSECUTION: after the requester's one comment, prosecution proceeds between the patent owner and the examiner only ('ex parte' = one-sided); (7) NOTICE OF INTENT TO ISSUE REEXAMINATION CERTIFICATE (NIRC): examiner concludes; patent owner can request reconsideration; (8) REEXAMINATION CERTIFICATE: issued; claims that survive are confirmed; cancelled claims are listed; amended claims are published; TYPICAL TIMELINE: 18–36 months from filing to certificate; THIRD-PARTY ANONYMITY: EPR is the only USPTO proceeding where the requesting party can remain completely anonymous; patent owner never learns who filed the request; useful for competitors who do not want to reveal their identity or litigation plans.

The AIA (2012) replaced inter partes reexamination (INTER PARTES REEX, 35 U.S.C. §§ 311–318) with IPR for patents with AIA effective dates. Key comparisons: EX PARTE REEXAMINATION vs. IPR: (1) REQUESTER PARTICIPATION: EPR = requester has only one comment opportunity, then locked out; IPR = petitioner fully participates throughout, submits reply briefs, depositions, expert declarations; (2) THRESHOLD: EPR = SNQ (lower); IPR = reasonable likelihood of prevailing (higher); (3) ESTOPPEL: EPR = none (no estoppel against district court arguments); IPR = § 315(e) estoppel if joined and final written decision — petitioner cannot assert grounds raised or reasonably could have raised in IPR; (4) ANONYMITY: EPR = anonymous filing permitted; IPR = RPI disclosure required (§ 312(a)(2)); (5) COST: EPR filing fee = $18,400; IPR filing fee = $20,000 (up to 20 claims); (6) APPEAL: EPR = patent owner appeals to PTAB then to CAFC; IPR = Federal Circuit review of PTAB decisions; (7) GROUNDS: same for both (§§ 102/103, prior art patents/publications only); INTER PARTES REEXAMINATION vs. EPR: inter partes reexamination (pre-AIA, available for patents filed on or after November 29, 1999) was more participatory than EPR; replaced by IPR; WHEN TO USE EPR vs. IPR: EPR preferred when: (1) requester wants to remain anonymous; (2) no estoppel risk desired; (3) challenger does not want to commit to full IPR resources; (4) patent is pre-AIA with unknown effective date; IPR preferred when: (1) stronger prior art; (2) full participation and discovery; (3) faster timeline (12–18 months vs. 18–36 months EPR).

EPR serves distinct strategic purposes that IPR does not: (1) ANONYMOUS COMPETITIVE INTELLIGENCE: a competitor can silently challenge a rival's key patent without revealing identity; the patent owner doesn't know who challenged the patent or why — preventing retaliation or early settlement pressure; (2) CLEARING FTO: companies performing freedom-to-operate analysis may file EPR to preemptively clear potentially blocking patents before product launch; if claims are cancelled or narrowed, the FTO analysis improves without the company becoming a named IPR petitioner; (3) NO ESTOPPEL RISK: EPR creates NO estoppel — the challenging party retains the right to raise any invalidity defense in district court litigation; this is the most significant strategic advantage over IPR; use EPR as a low-risk challenge that doesn't foreclose later district court arguments; (4) SUPPLEMENTING PROSECUTION: patent owners can request EPR of their own patent to: (a) confirm validity with a reexamination certificate (bolsters patent in future licensing or litigation); (b) amend claims to strengthen or broaden (broadening only permitted within first 2 years); (c) cite prior art cumulatively and get an examiner record showing patentability; (5) PARALLEL TO LITIGATION: EPR can be filed simultaneously with litigation without IPR's § 315(b) time-bar issues; there is no 1-year bar for EPR based on service of a complaint; (6) LITIGATION STAY: defendants can use EPR (filed by a third party if defendant wants anonymity) to seek a litigation stay — though courts are less likely to stay for EPR than for IPR because EPR takes longer and has no estoppel; (7) INTERNATIONAL: foreign parties who face US export controls or injunctions based on the patent can file anonymous EPR without triggering US presence or RPI disclosure.