1. Reexamination Defense Begins with the Prior Art Request
An ex parte reexamination request does not reopen every issue in an issued patent. The requester must identify a substantial new question of patentability based on patents or printed publications and explain how the cited art applies to the challenged claims.
The Request Must Map Prior Art to Claims
Under 35 U.S.C. § 302 and 37 C.F.R. § 1.510, the request must identify each challenged claim and explain the pertinency and application of the cited references. Reading that mapping claim by claim shows where the real dispute begins.
- List each challenged claim and the reference asserted against it.
- Check whether the request explains how each cited reference applies.
- Separate this USPTO record from broader patent law issues.
A 2026 Pre-Order Paper Adds an Early Choice
For requests filed on or after April 5, 2026, USPTO procedure allows a patent owner to file a pre-order paper before the § 303 decision. The paper must be filed within 30 days after service; that period is not extendable.
- Use the filing to explain why the alleged teaching would not be important to a reasonable examiner.
- Keep the paper limited to information relevant to the SNQ determination.
- Remember that § 303 still requires the USPTO to decide the request within three months.
2. The Patent Owner Faces an Early Response Choice
If the USPTO orders reexamination, the patent owner then decides whether to file the statement authorized by § 304 and whether claim changes are worth pursuing. That choice matters because a statement gives the requester one defined reply opportunity.
An Owner Statement Opens a Requester Reply
Section 304 gives the patent owner at least two months to file a statement addressing the new patentability question. If the owner files one, the requester has two months from service to reply.
- Decide whether the statement adds enough value to justify a requester reply.
- Keep the response tied to the patentability questions raised by the cited art.
- Coordinate proposed claim language with patent prosecution strategy.
Amendments Can Narrow but Not Enlarge Claims
Section 305 permits amended or new claims during reexamination, but no proposed claim may enlarge the scope of an existing patent claim. The owner should weigh patentability against the commercial value of narrower wording.
- Compare proposed language with the issued claim before filing.
- Test whether narrower wording still covers important products or methods.
- Record why the amendment answers the cited prior art.
3. Ex Parte Reexamination Is Examiner-Led, Not a PTAB Trial
After the statement and reply periods end, reexamination follows examination-style procedures. The examiner drives the patentability review, and the third-party requester loses its active role after the permitted reply. That structure is different from an adversarial PTAB trial.
The Requester'S Active Participation Ends Early
USPTO rules end the requester's active participation after the reply allowed by 37 C.F.R. § 1.535. The requester continues to receive Office actions and served papers, but cannot keep briefing the merits as a trial participant.
| Participant | Role after the Reply Stage |
|---|---|
| Patent owner | Responds to Office actions and may amend claims |
| Requester | Receives papers but has no continuing active role |
| Examiner | Conducts the patentability examination |
Patent owner
- Role after the Reply StageResponds to Office actions and may amend claims
Requester
- Role after the Reply StageReceives papers but has no continuing active role
Examiner
- Role after the Reply StageConducts the patentability examination
The Record Develops through Office Actions
The owner answers examiner rejections through written prosecution and may use permitted examiner interviews. Ex parte reexamination does not include ordinary civil discovery, a Markman hearing, or an adversarial merits trial.
- Build responses around the examiner's stated grounds.
- Use technical declarations or interviews when they fit the prosecution record.
- Compare other USPTO options through post-grant proceedings analysis.
4. Appeal and Certification Can Affect Parallel Litigation
A final rejection does not necessarily end the patent owner's options. The owner may appeal an adverse patentability decision, while the requester cannot participate in that appeal. The final certificate then identifies which claims remain, change, or are canceled.
The Patent Owner Controls the Appeal Path
Under § 306, the patent owner may appeal a final rejection to the Patent Trial and Appeal Board. After the Board's final decision, the owner may appeal the reexamination decision to the Federal Circuit under § 141.
- Preserve arguments needed for Board review in the written record.
- Keep appeal positions consistent with the reexamination history.
- Coordinate related federal litigation without treating the proceedings as identical.
The Certificate Defines the Resulting Claim Set
Section 307 requires a reexamination certificate after appeal rights end. It cancels claims finally found unpatentable, confirms claims found patentable, and incorporates patentable amended or new claims.
- Track which issued claims survive without amendment.
- Review the statutory effect of amended or new claims before enforcement decisions.
- Compare the certified claims with claims asserted in pending litigation.
5. Frequently Asked Questions
Can a patent owner request ex parte reexamination of its own patent?
Yes. A patent owner may file a request and may include a proposed amendment, subject to the applicable reexamination rules.
Can a physical product alone serve as the basis for the request?
The request must be based on prior art patents or printed publications. A physical product alone does not replace that statutory basis, although a qualifying publication about it may be relevant.
Can the patent owner interview the examiner during reexamination?
Yes. Examiner interviews are permitted in ex parte reexamination, but the third-party requester cannot attend or participate in those interviews.
Does filing ex parte reexamination automatically stop a related lawsuit?
No. Reexamination and litigation can proceed at the same time. Any stay must be sought and decided separately in the court case.
6. Review an Ex Parte Reexamination Defense with SJKP
SJKP's attorneys can review the reexamination request, cited prior art, claim strategy, USPTO responses, appeal options, and parallel litigation together. The firm can define the response around the claims and procedural posture actually at issue.
26 Aug, 2026
