US Code

Public Law 119-83 (04/13/2026)

35 U.S.C. § 315

Relation to other proceedings or actions

(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 sections 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 .—

section 1338 of title 28The 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 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.

Pub. L. 106–113, div. B, § 1000(a)(9) [title IV, § 4604(a)]113 Stat. 1536 Pub. L. 107–273, div. C, title III116 Stat. 1900–1902 Pub. L. 112–29, § 6(a)125 Stat. 300 (Added , , , 1501A–569; amended , §§ 13106(a), 13202(a)(4), (c)(1), , ; , , .)

Editorial Notes

References in Text

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

Amendments

Pub. L. 112–292011— amended section generally. Prior to amendment, section related to appeals.

Pub. L. 107–273, § 13202(c)(1)Pub. L. 106–1132002—, made technical correction to directory language of , which enacted this section.

Pub. L. 107–273, § 13106(a)Subsec. (b). , 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).”

Pub. L. 107–273, § 13202(a)(4)Subsec. (c). , struck out “United States Code,” after “title 28,”.

Statutory Notes and Related Subsidiaries

Effective Date of 2011 Amendment

Pub. L. 112–29section 6(c)(2) of Pub. L. 112–29section 311 of this titleAmendment by effective upon the expiration of the 1-year period beginning on , and applicable to any patent issued before, on, or after that effective date, with provisions for graduated implementation, see , set out as a note under .

Effective Date of 2002 Amendment

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

Effective Date

Pub. L. 106–113section 41 of this titleSection effective , 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 , set out as an Effective Date of 1999 Amendment note under .

Estoppel Effect of Reexamination

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