Us Code § 301 - Citation of prior art and written statements

Full text of Us Code United States Code § 301 — Citation of prior art and written statements, with citation guidance and answers to common questions.

§ 301. Citation of prior art and written statements

(a) In General.—Any person at any time may cite to the Office in writing—

(1) prior art consisting of patents or printed publications which that person believes to have a bearing on the patentability of any claim of a particular patent; or

(2) statements of the patent owner filed in a proceeding before a Federal court or the Office in which the patent owner took a position on the scope of any claim of a particular patent.


(b) Official File.—If the person citing prior art or written statements pursuant to subsection (a) explains in writing the pertinence and manner of applying the prior art or written statements to at least 1 claim of the patent, the citation of the prior art or written statements and the explanation thereof shall become a part of the official file of the patent.

(c) Additional Information.—A party that submits a written statement pursuant to subsection (a)(2) shall include any other documents, pleadings, or evidence from the proceeding in which the statement was filed that addresses the written statement.

(d) Limitations.—A written statement submitted pursuant to subsection (a)(2), and additional information submitted pursuant to subsection (c), shall not be considered by the Office for any purpose other than to determine the proper meaning of a patent claim in a proceeding that is ordered or instituted pursuant to section 304, 314, or 324. If any such written statement or additional information is subject to an applicable protective order, such statement or information shall be redacted to exclude information that is subject to that order.

(e) Confidentiality.—Upon the written request of the person citing prior art or written statements pursuant to subsection (a), that person's identity shall be excluded from the patent file and kept confidential.

(Added Pub. L. 96–517, §1, Dec. 12, 1980, 94 Stat. 3015; amended Pub. L. 112–29, §6(g)(1), Sept. 16, 2011, 125 Stat. 311.)


Editorial Notes

Amendments

2011—Pub. L. 112–29 amended section generally. Prior to amendment, text read as follows: "Any person at any time may cite to the Office in writing prior art consisting of patents or printed publications which that person believes to have a bearing on the patentability of any claim of a particular patent. If the person explains in writing the pertinency and manner of applying such prior art to at least one claim of the patent, the citation of such prior art and the explanation thereof will become a part of the official file of the patent. At the written request of the person citing the prior art, his or her identity will be excluded from the patent file and kept confidential."


Statutory Notes and Related Subsidiaries

Effective Date of 2011 Amendment

Pub. L. 112–29, §6(g)(3), Sept. 16, 2011, 125 Stat. 312, provided that: "The amendments made by this subsection [amending this section] shall take effect upon the expiration of the 1-year period beginning on the date of the enactment of this Act [Sept. 16, 2011] and shall apply to any patent issued before, on, or after that effective date."

Effective Date

Section effective July 1, 1981, and applicable to patents in force as of July 1, 1981, or issued thereafter, see section 8(b) of Pub. L. 96–517, set out as an Effective Date of 1980 Amendment note under section 41 of this title.

About This Section

35 U.S.C. § 301 is part of Title 35 of the United States Code. The United States Code is the official codification of federal statutes maintained by the Office of the Law Revision Counsel of the U.S. House of Representatives. Congress amends the Code through new public laws, which are eventually incorporated into the relevant title.

This section may be cited in legal writing as 35 U.S.C. § 301. For the most current official text, including any recent amendments, use the official source links below. Do not rely on this page as the sole authority for legal citation or litigation.

How to Read This Statute

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This page is intended for research and educational use. Lawyers, students, journalists, and compliance professionals can use it as a starting point, but should always verify the current text through an official government source before relying on it for legal advice, filings, or compliance decisions.

Sources

Source: official Us Code text · Last verified 2026-08-27

Frequently Asked Questions About Us Code § 301

What does United States Code § 301 cover?

Section 301 ("Citation of prior art and written statements") is part of the United States Code, the codified statutory law of Us Code. It sets out the legal rule or procedure described in the text above. Statutes are amended regularly, so always verify against the official source.

How do I cite Us Code § 301?

A common citation format is "United States Code § 301" (Us Code). Legal writing may require the code abbreviation, section number, and year or edition. Match the style required by your court, professor, or publisher.

Is this the official text of Us Code law?

No. This page is for research and education and may not include the most recent amendments. For official current law, check the Us Code official source linked on this page or consult a licensed Us Code attorney.

How does Us Code § 301 apply to my situation?

Statutes are interpreted in context, and application depends on your specific facts. Only a licensed attorney in Us Code can advise on how this section applies to you. Contact your state or local bar association for a referral.

Sources & Verification

Not legal advice. Verify against the official source and consult a licensed attorney in Us Code.