37 CFR § 42.107 - Preliminary response to petition.

---
identifier: "/us/cfr/t37/s42.107"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "37 CFR § 42.107 - Preliminary response to petition."
title_number: 37
title_name: "Patents, Trademarks, and Copyrights"
section_number: "42.107"
section_name: "Preliminary response to petition."
chapter_name: "UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE"
subchapter_number: "A"
subchapter_name: "GENERAL"
part_number: "42"
part_name: "TRIAL PRACTICE BEFORE THE PATENT TRIAL AND APPEAL BOARD"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "35 U.S.C. 2(b)(2), 3, 6, 21, 23, 41, 134, 135, 143, 153, 311, 312, 314, 316, 318, 321-326, 328; Pub. L. 112-29, 125 Stat. 284; and Pub. L. 112-274, 126 Stat. 2456."
regulatory_source: "77 FR 48669, Aug. 14, 2012, unless otherwise noted."
cfr_part: "42"
---


# 42.107 Preliminary response to petition.

(a) The patent owner may file a preliminary response to the petition. The response is limited to setting forth the reasons why no *inter partes* review should be instituted under 35 U.S.C. 314 and can include supporting evidence. The preliminary response is subject to the word count under § 42.24.

(b) *Due date.* The preliminary response must be filed no later than three months after the date of a notice indicating that the request to institute an *inter partes* review has been granted a filing date. A patent owner may expedite the proceeding by filing an election to waive the patent owner preliminary response.

(c) [Reserved]

(d) *No amendment.* The preliminary response shall not include any amendment.

(e) *Disclaim Patent Claims.* The patent owner may file a statutory disclaimer under 35 U.S.C. 253(a) in compliance with § 1.321(a) of this chapter, disclaiming one or more claims in the patent. No *inter partes* review will be instituted based on disclaimed claims.

[77 FR 48727, Aug. 14, 2012, as amended at 81 FR 18766, Apr. 1, 2016]