37 CFR § 1.948 - Limitations on submission of prior art by third party requester following the order for reexamination.

---
identifier: "/us/cfr/t37/s1.948"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "37 CFR § 1.948 - Limitations on submission of prior art by third party requester following the order for  reexamination."
title_number: 37
title_name: "Patents, Trademarks, and Copyrights"
section_number: "1.948"
section_name: "Limitations on submission of prior art by third party requester following the order for  reexamination."
chapter_name: "UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE"
subchapter_number: "A"
subchapter_name: "GENERAL"
part_number: "1"
part_name: "RULES OF PRACTICE IN PATENT CASES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "35 U.S.C. 2(b)(2), unless otherwise noted."
regulatory_source: "24 FR 10332, Dec. 22, 1959, unless otherwise noted."
cfr_part: "1"
---


# 1.948 Limitations on submission of prior art by third party requester following the order for  reexamination.

(a) After the *inter partes* reexamination order, the third party requester may only cite additional prior art as defined under § 1.501 if it is filed as part of a comments submission under § 1.947 or § 1.951(b) and is limited to prior art:

(1) which is necessary to rebut a finding of fact by the examiner;

(2) which is necessary to rebut a response of the patent owner; or

(3) which for the first time became known or available to the third party requester after the filing of the request for *inter partes* reexamination proceeding. Prior art submitted under paragraph (a)(3) of this section must be accompanied by a statement as to when the prior art first became known or available to the third party requester and must include a discussion of the pertinency of each reference to the patentability of at least one claim.

(b) [Reserved]