Chapter 1400
Chapter 1400 covers correction of issued patents through certificates of correction, reissue applications, and disclaimers. Key rule: broadening reissue MUST be filed within 2 years of patent grant — absolute deadline with no exceptions.
Core Concepts
Certificate of Correction — 35 USC 255 / MPEP 1481 Corrects minor errors in issued patents. USPTO error: certificate issued without fee. Applicant error: certificate issued with fee. Cannot be used to add new matter or broaden claims. Used for typographical errors, incorrect drawings, minor claim corrections.
Reissue Application — 35 USC 251 / MPEP 1401 Used to correct defective issued patent — error must have arisen without deceptive intent. Can broaden OR narrow claims. Broadening reissue: MUST file within 2 years of patent grant — absolute, no exceptions. Narrowing reissue: can file anytime during patent term.
Recapture Rule — MPEP 1412.02 Cannot use reissue to reclaim subject matter deliberately surrendered during prosecution to overcome rejection. Partial recapture may be allowed if claims are materially narrowed relative to surrendered subject matter. Recapture is an absolute bar — most tested reissue concept.
Intervening Rights — 35 USC 252 / MPEP 1460 Third party who makes/uses/sells patented article between grant and reissue has intervening rights. Absolute intervening rights: acts completed before reissue date protected. Equitable intervening rights: court discretion for ongoing activities. Critical rule: amended or new claims in reissue do not affect intervening rights for pre-reissue activity.
Disclaimer — 35 USC 253 / MPEP 1490 Statutory disclaimer: applicant dedicates entire patent or specific claims to public. Terminal disclaimer: limits patent term — used to overcome ODP. Filed with fee. Irrevocable once accepted.
Reexamination — MPEP 2209/2611 Ex parte reexamination: any person can request, based on patents or printed publications only. Inter partes reexamination: replaced by IPR under AIA for most purposes. Substantial new question of patentability (SNQ) required to order reexamination.
Key Rules
EXAM TIP
Two most tested concepts: (1) Broadening reissue 2-year absolute deadline — no petition, no extension, no exceptions. (2) Recapture rule — deliberately surrendered subject matter cannot be reclaimed through reissue, even if within 2 years. Both are absolute rules.
Common Traps
Search Terms
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