MPEP 2234
Entry of Amendments

Ninth Edition of the MPEP, Revision 10.2019, Last Revised in June 2020

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2234    Entry of Amendments [R-07.2015]

37 C.F.R. 1.121 Manner of making amendments in applications.


  • (j) Amendments in reexamination proceedings. Any proposed amendment to the description and claims in patents involved in reexamination proceedings must be made in accordance with § 1.530.


37 C.F.R. 1.530 Statement by patent owner in ex parte reexamination; amendment by patent owner in ex parte or inter partes reexamination; inventorship change in ex parte or inter partes reexamination.


  • (d) Making amendments in a reexamination proceeding. A proposed amendment in an ex parte or an inter partes reexamination proceeding is made by filing a paper directing that proposed specified changes be made to the patent specification, including the claims, or to the drawings. An amendment paper directing that proposed specified changes be made in a reexamination proceeding may be submitted as an accompaniment to a request filed by the patent owner in accordance with § 1.510(e), as part of a patent owner statement in accordance with paragraph (b) of this section, or, where permitted, during the prosecution of the reexamination proceeding pursuant to § 1.550(a) or § 1.937.
    • (1) Specification other than the claims. Changes to the specification, other than to the claims, must be made by submission of the entire text of an added or rewritten paragraph including markings pursuant to paragraph (f) of this section, except that an entire paragraph may be deleted by a statement deleting the paragraph, without presentation of the text of the paragraph. The precise point in the specification must be identified where any added or rewritten paragraph is located. This paragraph applies whether the amendment is submitted on paper or compact disc ( see §§ 1.96 and 1.825 ).
    • (2) Claims. An amendment paper must include the entire text of each patent claim which is being proposed to be changed by such amendment paper and of each new claim being proposed to be added by such amendment paper. For any claim changed by the amendment paper, a parenthetical expression "amended," "twice amended," etc., should follow the claim number. Each patent claim proposed to be changed and each proposed added claim must include markings pursuant to paragraph (f) of this section, except that a patent claim or proposed added claim should be canceled by a statement canceling the claim, without presentation of the text of the claim.
    • (3) Drawings. Any change to the patent drawings must be submitted as a sketch on a separate paper showing the proposed changes in red for approval by the examiner. Upon approval of the changes by the examiner, only new sheets of drawings including the changes and in compliance with § 1.84 must be filed. Amended figures must be identified as "Amended," and any added figure must be identified as "New." In the event a figure is canceled, the figure must be surrounded by brackets and identified as "Canceled."
    • (4) The formal requirements for papers making up the reexamination proceeding other than those set forth in this section are set out in § 1.52.
  • (e) Status of claims and support for claim changes. Whenever there is an amendment to the claims pursuant to paragraph (d) of this section, there must also be supplied, on pages separate from the pages containing the changes, the status (i.e., pending or canceled), as of the date of the amendment, of all patent claims and of all added claims, and an explanation of the support in the disclosure of the patent for the changes to the claims made by the amendment paper.
  • (f) Changes shown by markings. Any changes relative to the patent being reexamined which are made to the specification, including the claims, must include the following markings:
    • (1) The matter to be omitted by the reexamination proceeding must be enclosed in brackets; and
    • (2) The matter to be added by the reexamination proceeding must be underlined.
  • (g) Numbering of patent claims preserved. Patent claims may not be renumbered. The numbering of any claims added in the reexamination proceeding must follow the number of the highest numbered patent claim.
  • (h) Amendment of disclosure may be required. The disclosure must be amended, when required by the Office, to correct inaccuracies of description and definition, and to secure substantial correspondence between the claims, the remainder of the specification, and the drawings.
  • (i) Amendments made relative to patent. All amendments must be made relative to the patent specification, including the claims, and drawings, which are in effect as of the date of filing the request for reexamination.
  • (j) No enlargement of claim scope. No amendment may enlarge the scope of the claims of the patent or introduce new matter. No amendment may be proposed for entry in an expired patent. Moreover, no amendment, other than the cancellation of claims, will be incorporated into the patent by a certificate issued after the expiration of the patent.
  • (k) Amendments not effective until certificate. Although the Office actions will treat proposed amendments as though they have been entered, the proposed amendments will not be effective until the reexamination certificate is issued and published.


Amendments which comply with 37 CFR 1.530(d) through (j) (and are formally presented pursuant to 37 CFR 1.52(a) and 37 CFR 1.52(b), and contain all fees required by 37 CFR 1.20(c) ) are entered in the reexamination file.

Patent claims must not be renumbered, and the numbering of the claims added during reexamination must follow the number of the highest numbered patent claim.

ALL amendments in reexamination proceedings, including examiner’s amendments made at the time when the Notice of Intent to Issue Ex Parte Reexamination Certificate (NIRC) is prepared (37 CFR 1.121(g) does not apply in reexamination proceedings), must be presented in the form of a full copy of the text of each claim which is amended and each paragraph of the description which is amended. In other words, the entire claim or paragraph must be presented for any amendment of the claim or paragraph.

If a portion of the text is amended more than once, each amendment should indicate ALL of the changes (insertions and deletions) in relation to the current text of the patent under reexamination.

Although amendments will be entered for purposes of examination, the amendments are not legally effective until the reexamination certificate is issued and published.

See MPEP § 2250 for manner of making amendments by patent owner and for examples of proper claim amendment format. For clerical handling of amendments, see MPEP § 2270. See also MPEP § 2221 for amendments included in the request filed under 35 U.S.C. 302 by the patent owner. For entry of amendments in a merged proceeding, see MPEP § 2283 and § 2285.