Reexamination vs. IPR

Ex parte reexamination (EPR) and inter partes review (IPR) are both USPTO procedures for challenging issued patents on prior art grounds, but they differ fundamentally in procedure, timing, participation, and outcome: EX PARTE REEXAMINATION (EPR): governed by 35 U.S.C. §§ 302–307; any person (even an anonymous third party) may request EPR; the requester files a request identifying prior art; USPTO determines whether there is a 'substantial new question of patentability' (SNQ) — a lower threshold than IPR institution; if EPR is ordered, prosecution is conducted by an examiner with the patent owner; THE REQUESTER DROPS OUT: after the EPR is ordered, the third-party requester has NO FURTHER PARTICIPATION except for filing one reply after the patent owner's first response to any prior art rejection; the requester cannot participate in examiner interviews, submit further art, or appeal the outcome (only the patent owner can appeal); result: EPR is primarily a way to put prior art in front of the examiner, not an adversarial proceeding; INTER PARTES REVIEW (IPR): governed by 35 U.S.C. §§ 311–319; only a person who is not the patent owner and has not been served with a complaint alleging infringement for more than one year; filed with PTAB (not an examiner); adversarial trial proceeding with full participation by both sides; institution standard: 'reasonable likelihood petitioner prevails on ≥1 claim'; TIMING: EPR has NO timing bar (can file at any time, even during litigation); IPR has a 1-year bar from service of complaint (§ 315(b)); ESTOPPEL: EPR creates no estoppel; IPR creates estoppel in district court for grounds raised or reasonably could have been raised after FWD.

Ex parte reexamination has specific use cases where it is superior to IPR: ADVANTAGES OF EPR: NO TIMING BAR: EPR can be filed at any time — before litigation, during litigation, even after a district court verdict on invalidity (the patent could be reexamined and claims narrowed even after a verdict); unlike IPR which is barred 1 year after complaint service; NO STANDING REQUIREMENT: any person can file EPR; does not require being a defendant in litigation; ideal for third parties who want to clear a problematic patent before they are sued; LOWER COST: EPR costs $12,000–$50,000 in attorney fees vs. $300K–$500K for IPR; LOW FILING FEE: $16,120 (large entity) vs. $19,000+ for IPR; ANONYMITY: EPR can be filed anonymously through a third party; useful for companies that don't want to reveal they are worried about a patent before being sued; NO ESTOPPEL: EPR creates no estoppel for the requester in subsequent district court proceedings; can raise the same art again in litigation; DISADVANTAGES OF EPR: MINIMAL PARTICIPATION: after the initial request and one reply, the requester is out of the proceeding; SLOW: EPR proceedings take 2–4 years on average (vs. ~18 months for IPR); cannot be expedited unless combined with concurrent litigation; LOW INVALIDATION RATE: the examiner reviews claims with a patent owner who can argue and amend; EPR success rate (claim cancellation) is much lower than IPR (~30–40% of requests result in at least one claim being cancelled vs. ~60–70% of instituted IPRs); NO DEPOSITIONS OR ORAL ARGUMENT: EPR is a written-only proceeding before an examiner; no oral testimony, no cross-examination of experts; SNQP STANDARD IS LOW, BUT: even when SNQ is found and EPR ordered, the examiner may ultimately confirm all claims — the patent owner can traverse every rejection in writing.

Despite IPR's higher cancellation rate, there are specific scenarios where EPR is the better choice: SCENARIO 1 — PAST THE 1-YEAR IPR WINDOW: if you have been sued for more than 1 year (§ 315(b) time bar), IPR is unavailable; EPR has no timing bar; use EPR to continue invalidating the patent even after IPR becomes unavailable; this is the most common reason to choose EPR over IPR; SCENARIO 2 — PRESERVING INVALIDITY ARGUMENTS FOR DISTRICT COURT: IPR estoppel bars raising in district court any prior art that was raised OR reasonably could have been raised in the IPR; EPR creates no estoppel; if you need to preserve all invalidity arguments for district court, EPR puts some art in the record without estopping other art; strategic note: this only works if the art you put in EPR is clearly your weakest art — the strong art must be preserved for district court; SCENARIO 3 — ANONYMOUS CLEARANCE BEFORE SUIT: if you want to challenge a patent before being sued (clearance work), EPR can be filed anonymously without triggering any IPR time bar issues; SCENARIO 4 — LOW BUDGET: $50,000 total cost for EPR vs. $300,000–$500,000 for IPR; startups and small companies with limited litigation budgets may use EPR to pursue invalidation when IPR cost is prohibitive; SCENARIO 5 — SUPPLEMENTAL EXAMINATION FOR PATENT OWNERS: patent owners can self-request EPR (supplemental examination) to cure potential inequitable conduct issues; submit prior art the inventor knew about but didn't disclose to the USPTO; supplemental examination shields the patent from inequitable conduct claims for the submitted art; WHEN IPR IS SUPERIOR: when within 1 year of complaint service; when a fast, final result is needed (IPR has a 12-month FWD deadline; EPR has no deadline); when the prior art is strong and full adversarial presentation would strengthen the challenge; when the requester wants direct participation and oral argument.

EPR and district court litigation can run simultaneously, creating complex strategic interactions: NO AUTOMATIC STAY: filing an EPR request does NOT automatically stay district court proceedings; motion to stay is required; courts are generally reluctant to stay cases for EPR because EPR is slow (2–4 years) and the requester has minimal participation; IPR stays are more commonly granted because of the faster timeline and higher cancellation rate; COURT'S STAY ANALYSIS: the same 3-factor test applies as for IPR stays: (1) stage of litigation; (2) prejudice to patent owner; (3) whether EPR would simplify the issues; for EPR: factor 3 weighs against stay because EPR may not simplify issues (claims can only be narrowed, not broadened in EPR; the examiner may confirm all claims); CLAIM SCOPE NARROWING: if EPR results in claim narrowing (the examiner allows amended narrower claims), the district court damages and infringement analysis changes; narrowed claims may provide absolute intervening rights to the defendant for products made before reexamination certificate; PROSECUTION HISTORY: the EPR prosecution history becomes part of the patent's file history; arguments made in EPR can limit claim scope via prosecution history estoppel in district court (just as original prosecution arguments do); PATENT OWNER'S AMENDMENT STRATEGY: during EPR, the patent owner typically narrows claims to avoid the prior art; this creates prosecution history estoppel and may eliminate infringement by the very product that prompted the EPR request; FINAL CERTIFICATE: when EPR concludes, a reexamination certificate issues confirming, amending, or canceling claims; this certificate is the operative claim set going forward in all proceedings.

Post-grant review (PGR) is a third PTAB proceeding that allows broader invalidity challenges than IPR but has a strict 9-month filing window: PGR BASIS: 35 U.S.C. §§ 321–329; available only for patents with an effective filing date on or after March 16, 2013 (first-inventor-to-file patents under AIA); filing window: within 9 MONTHS of the patent's grant or reissuance; ANY § 112, § 102, § 103, OR § 101 GROUNDS: unlike IPR (prior art § 102/103 only), PGR can challenge: § 112 written description, enablement, indefiniteness; § 101 patent eligibility (abstract idea); § 102/103 prior art; INSTITUTION STANDARD: 'more likely than not that at least one challenged claim is unpatentable' — slightly higher standard than IPR's 'reasonable likelihood'; ADVERSARIAL PROCEEDINGS: same trial format as IPR (PTAB panel of 3 APJs; briefing; expert cross-examination; oral argument; FWD within 12 months of institution); ESTOPPEL: same estoppel rules as IPR — after FWD, petitioner estopped from raising grounds raised or reasonably could have been raised in district court; TACTICAL USE: file PGR within 9 months for newly granted patents with § 112 invalidity concerns (written description, enablement, indefiniteness); these grounds are unavailable in IPR; IPR timing: also 9 months to file PGR; if you miss the PGR window, IPR is the next available PTAB proceeding (with its prior-art-only limitation); COMPARISON SUMMARY: EPR = any time, no estoppel, slow, minimal participation, low cost; IPR = within 1 year of complaint, estoppel, fast, adversarial, prior art only; PGR = within 9 months of grant, estoppel, fast, adversarial, any invalidity ground; each fills a different strategic niche.