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Title 35, PatentsRelease 119-110

§315 Relation to Other Proceedings or Actions

Title 35 › PART III — PATENTS AND PROTECTION OF PATENT RIGHTS › CHAPTER 31 — INTER PARTES REVIEW › § 315

Last updated Sep 22, 2026|Official source

Summary

Controls when an inter partes review can start, what happens to related court cases, and what limits apply after the review ends. You cannot start an inter partes review if the petitioner or a related party already filed a civil lawsuit challenging the same patent claim before filing the review petition. If the petitioner files a civil lawsuit after filing the review petition, that lawsuit is automatically paused until the patent owner asks the court to lift the pause, the patent owner files a civil action or counterclaim saying the petitioner infringed, or the petitioner asks the court to dismiss the suit. A counterclaim that only challenges validity does not count as starting a civil action for these rules. A petition for review must be filed within 1 year after the petitioner or a related party was served with an infringement complaint; that one-year limit does not apply to requests to join an existing review. The Patent Office Director may add other qualified petitioners as parties after a preliminary response or its deadline. While a review is pending, the Director can decide how other Patent Office matters about the same patent proceed, including pausing, moving, combining, or ending them. If the review ends with a final written decision, the petitioner (and its real parties in interest or privies) may not later challenge that same claim before the Patent Office, in a civil action under 28 U.S.C. 1338, or in a proceeding before the International Trade Commission under section 337 on any ground they raised or reasonably could have raised during the review.

Full Legal Text

Title 35, §315

Patents, Source: USLM XML via OLRC

(a)Infringer’s Civil Action.—
(1)Inter partes review barred by civil action.—
An inter partes review may not be instituted if, before the date on which the petition for such a review is filed, the petitioner or real party in interest filed a civil action challenging the validity of a claim of the patent.
(2)Stay of civil action.—
If the petitioner or real party in interest files a civil action challenging the validity of a claim of the patent on or after the date on which the petitioner files a petition for inter partes review of the patent, that civil action shall be automatically stayed until either—
(A)the patent owner moves the court to lift the stay;
(B)the patent owner files a civil action or counterclaim alleging that the petitioner or real party in interest has infringed the patent; or
(C)the petitioner or real party in interest moves the court to dismiss the civil action.
(3)Treatment of counterclaim.—
A counterclaim challenging the validity of a claim of a patent does not constitute a civil action challenging the validity of a claim of a patent for purposes of this subsection.
(b)Patent Owner’s Action.—
An inter partes review may not be instituted if the petition requesting the proceeding is filed more than 1 year after the date on which the petitioner, real party in interest, or privy of the petitioner is served with a complaint alleging infringement of the patent. The time limitation set forth in the preceding sentence shall not apply to a request for joinder under subsection (c).
(c)Joinder.—
If the Director institutes an inter partes review, the Director, in his or her discretion, may join as a party to that inter partes review any person who properly files a petition under section 311 that the Director, after receiving a preliminary response under section 313 or the expiration of the time for filing such a response, determines warrants the institution of an inter partes review under section 314.
(d)Multiple Proceedings.—
Notwithstanding section 135(a), 251, and 252, and chapter 30, during the pendency of an inter partes review, if another proceeding or matter involving the patent is before the Office, the Director may determine the manner in which the inter partes review or other proceeding or matter may proceed, including providing for stay, transfer, consolidation, or termination of any such matter or proceeding.
(e)Estoppel.—
(1)Proceedings before the office.—
The petitioner in an inter partes review of a claim in a patent under this chapter that results in a final written decision under section 318(a), or the real party in interest or privy of the petitioner, may not request or maintain a proceeding before the Office with respect to that claim on any ground that the petitioner raised or reasonably could have raised during that inter partes review.
(2)Civil actions and other proceedings.—
The petitioner in an inter partes review of a claim in a patent under this chapter that results in a final written decision under section 318(a), or the real party in interest or privy of the petitioner, may not assert either in a civil action arising in whole or in part under section 1338 of title 28 or in a proceeding before the International Trade Commission under section 337 of the Tariff Act of 1930 that the claim is invalid on any ground that the petitioner raised or reasonably could have raised during that inter partes review.

Legislative History

Notes & Related Subsidiaries

Editorial Notes

References in Text

section 337 of the Tariff Act of 1930, referred to in subsec. (e)(2), is classified to section 1337 of Title 19, Customs Duties.

Amendments

2011—Pub. L. 112–29 amended section generally. Prior to amendment, section related to appeals. 2002—Pub. L. 107–273, § 13202(c)(1), made technical correction to directory language of Pub. L. 106–113, which enacted this section. Subsec. (b). Pub. L. 107–273, § 13106(a), reenacted heading without change and amended text generally. Prior to amendment, text read as follows: “A third-party requester may— “(1) appeal under the provisions of section 134 with respect to any final decision favorable to the patentability of any original or proposed amended or new claim of the patent; or “(2) be a party to any appeal taken by the patent owner under the provisions of section 134, subject to subsection (c).” Subsec. (c). Pub. L. 107–273, § 13202(a)(4), struck out “United States Code,” after “title 28,”.

Statutory Notes and Related Subsidiaries

Effective Date

of 2011 AmendmentAmendment by Pub. L. 112–29 effective upon the expiration of the 1-year period beginning on Sept. 16, 2011, and applicable to any patent issued before, on, or after that

Effective Date

, with provisions for graduated implementation, see section 6(c)(2) of Pub. L. 112–29, set out as a note under section 311 of this title.

Effective Date

of 2002 AmendmentAmendment by section 13106(a) of Pub. L. 107–273 applicable with respect to any reexamination proceeding commenced on or after Nov. 2, 2002, see section 13106(d) of Pub. L. 107–273, set out as a note under section 134 of this title.

Effective Date

Section effective Nov. 29, 1999, and applicable to any patent issuing from an original application filed in the United States on or after that date, see section 1000(a)(9) [title IV, § 4608(a)] of Pub. L. 106–113, set out as an

Effective Date

of 1999 Amendment note under section 41 of this title. Estoppel Effect of Reexamination Pub. L. 106–113, div. B, § 1000(a)(9) [title IV, subtitle F, § 4607], Nov. 29, 1999, 113 Stat. 1536, 1501A–571, provided for estoppel from challenging certain facts determined during inter partes reexamination under former section 311 of this title and contained a

Severability

provision.

Reference

Citations & Metadata

Citation

35 U.S.C. § 315

Title 35, Patents

Last Updated

Sep 22, 2026

Release point: 119-110