MPEP § 1834 — Correspondence (Annotated Rules)

§1834 Correspondence

USPTO MPEP version: BlueIron's Update: 2025-12-31

This page consolidates and annotates all enforceable requirements under MPEP § 1834, including statutory authority, regulatory rules, examiner guidance, and practice notes. It is provided as guidance, with links to the ground truth sources. This is information only, it is not legal advice.

Correspondence

This section addresses Correspondence. Primary authority: 37 CFR 1.10, 37 CFR 1.10(c), and 37 CFR 1.8. Contains: 4 requirements, 1 prohibition, and 4 other statements.

Key Rules

Topic

Request Content and Form

4 rules
MPEP GuidanceRequiredAlways
[mpep-1834-411e905fe8ef07aeda0432c3]
Requirement for Accompanying Letter Identifying International Application
Note:
Any paper submitted by the applicant, other than the international application itself, must be accompanied by a letter identifying the related international application and signed by the applicant.

(a) Any paper submitted by the applicant in the course of the international procedure provided for in the Treaty and these Regulations, other than the international application itself, shall, if not itself in the form of a letter, be accompanied by a letter identifying the international application to which it relates. The letter shall be signed by the applicant.

Jump to MPEP SourceRequest Content and FormSignature RequirementsPCT Request Form
MPEP GuidanceRequiredAlways
[mpep-1834-919675899a8db64d44488cea]
First Named Applicant Required for Identification
Note:
For international applications with multiple applicants, it is sufficient to identify the application by indicating the name of the first named applicant in any form or correspondence.

Where any international application indicates two or more applicants, it shall be sufficient, for the purpose of identifying that application, to indicate, in any Form or correspondence relating to such application, the name of the applicant first named in the request. The provisions of the first sentence of this Section do not apply to the demand.

Jump to MPEP SourceRequest Content and FormSignature RequirementsPCT Request Form
MPEP GuidanceInformativeAlways
[mpep-1834-33c28a5aa9fab1de87b0d40f]
Requirement for Identifying Letters to International Application
Note:
The Office requires letters accompanying papers other than the international application to identify the related application and be signed. Failure to comply results in notification and a time limit to remedy the omission.

If the Office finds that papers, other than the international application itself, are not accompanied by a letter identifying the international application to which they relate, or are accompanied by an unsigned letter, or are furnished in the form of an unsigned letter, it notifies the applicant and invites him or her to remedy the omission. The Office disregards the said papers or letter if the omission is not remedied within the time limit fixed in the invitation (PCT Rule 92.1(b)). If the omission has been overlooked and the paper taken into account, the omission is disregarded.

Jump to MPEP SourceRequest Content and FormSignature RequirementsPCT Request Form
MPEP GuidanceInformativeAlways
[mpep-1834-b92c0a326c6eb59a5dd4498e]
Omission of Identification Not Remedied Is Ignored
Note:
If the Office overlooks an omission in identifying the international application and processes a paper without proper identification, the omission is disregarded if not remedied within the time limit.

If the Office finds that papers, other than the international application itself, are not accompanied by a letter identifying the international application to which they relate, or are accompanied by an unsigned letter, or are furnished in the form of an unsigned letter, it notifies the applicant and invites him or her to remedy the omission. The Office disregards the said papers or letter if the omission is not remedied within the time limit fixed in the invitation (PCT Rule 92.1(b)). If the omission has been overlooked and the paper taken into account, the omission is disregarded.

Jump to MPEP SourceRequest Content and FormSignature RequirementsPCT Request Form
Topic

Certificate of Mailing

3 rules
StatutoryProhibitedAlways
[mpep-1834-0b4b3a62680e6fb78338afaa]
Certificate of Mailing Cannot Be Used for International Stage Filings
Note:
The certificate of mailing procedure set forth at 37 CFR 1.8 cannot be used to file papers during the international stage if a specific date of deposit is required.

The certificate of mailing by first class mail procedure set forth at 37 CFR 1.8 differs from the 37 CFR 1.10 Priority Mail Express® procedure. See 37 CFR 1.8(a)(2)(i)(D) and (E). It is important to understand that the 37 CFR 1.8 certificate of mailing procedure CANNOT be used for filing any papers during the international stage if the date of deposit is desired. If the 37 CFR 1.8 certificate of mailing procedure is used, the paper and/or fee will be accorded the date of receipt in the USPTO unless the receipt date falls on a Saturday, Sunday, or federal holiday in which case the date of receipt will be the next succeeding day which is not a Saturday, Sunday, or federal holiday (37 CFR 1.6(a)(1)). Accordingly, the certificate of mailing procedures of 37 CFR 1.8 are not available to have a submission during the international stage considered as timely filed if the submission is not physically received at the USPTO on or before the due date.

Jump to MPEP Source · 37 CFR 1.8Certificate of MailingExpress Mail Filing Date
StatutoryInformativeAlways
[mpep-1834-6fed5b47957df9f1e92beafa]
Certificate of Mailing Date Adjustment
Note:
If the certificate of mailing procedure is used, the filing date will be adjusted to the next business day if received on a weekend or holiday.

The certificate of mailing by first class mail procedure set forth at 37 CFR 1.8 differs from the 37 CFR 1.10 Priority Mail Express® procedure. See 37 CFR 1.8(a)(2)(i)(D) and (E). It is important to understand that the 37 CFR 1.8 certificate of mailing procedure CANNOT be used for filing any papers during the international stage if the date of deposit is desired. If the 37 CFR 1.8 certificate of mailing procedure is used, the paper and/or fee will be accorded the date of receipt in the USPTO unless the receipt date falls on a Saturday, Sunday, or federal holiday in which case the date of receipt will be the next succeeding day which is not a Saturday, Sunday, or federal holiday (37 CFR 1.6(a)(1)). Accordingly, the certificate of mailing procedures of 37 CFR 1.8 are not available to have a submission during the international stage considered as timely filed if the submission is not physically received at the USPTO on or before the due date.

Jump to MPEP Source · 37 CFR 1.8Certificate of MailingExpress Mail Filing Date
StatutoryInformativeAlways
[mpep-1834-fb363c473d99939d88a935c5]
Certificate of Mailing Not Timely During International Stage
Note:
A certificate of mailing under 37 CFR 1.8 cannot be used to consider a submission timely filed during the international stage if not physically received by the USPTO on or before the due date.

The certificate of mailing by first class mail procedure set forth at 37 CFR 1.8 differs from the 37 CFR 1.10 Priority Mail Express® procedure. See 37 CFR 1.8(a)(2)(i)(D) and (E). It is important to understand that the 37 CFR 1.8 certificate of mailing procedure CANNOT be used for filing any papers during the international stage if the date of deposit is desired. If the 37 CFR 1.8 certificate of mailing procedure is used, the paper and/or fee will be accorded the date of receipt in the USPTO unless the receipt date falls on a Saturday, Sunday, or federal holiday in which case the date of receipt will be the next succeeding day which is not a Saturday, Sunday, or federal holiday (37 CFR 1.6(a)(1)). Accordingly, the certificate of mailing procedures of 37 CFR 1.8 are not available to have a submission during the international stage considered as timely filed if the submission is not physically received at the USPTO on or before the due date.

Jump to MPEP Source · 37 CFR 1.8Certificate of MailingMaintenance Fee Due Dates
Topic

Priority Mail Express

2 rules
StatutoryInformativeAlways
[mpep-1834-870ff665868f8f3ab94029e5]
Priority Mail Express for International Applications
Note:
Papers filed with the USPTO in international applications must use Priority Mail Express and comply with 37 CFR 1.10 to have the mailing label date accepted as the filing date.

The Priority Mail Express® procedure set forth at 37 CFR 1.10 applies to papers filed with the U.S. Patent and Trademark Office (USPTO) in international applications. Accordingly, papers filed with the USPTO in international applications will be accorded by the USPTO the “date accepted” indicated on the Priority Mail Express® mailing label as the date of filing in the USPTO if the provisions of 37 CFR 1.10 are complied with. See MPEP § 513.

Jump to MPEP Source · 37 CFR 1.10Priority Mail ExpressCertificate of Mailing and TransmissionPCT International Application Filing
StatutoryInformativeAlways
[mpep-1834-efd6d1e0eacf6df7769951f1]
Date of Filing via Priority Mail Express
Note:
Papers filed with the USPTO in international applications will be considered filed on the date indicated on the Priority Mail Express mailing label if certain requirements are met.

The Priority Mail Express® procedure set forth at 37 CFR 1.10 applies to papers filed with the U.S. Patent and Trademark Office (USPTO) in international applications. Accordingly, papers filed with the USPTO in international applications will be accorded by the USPTO the “date accepted” indicated on the Priority Mail Express® mailing label as the date of filing in the USPTO if the provisions of 37 CFR 1.10 are complied with. See MPEP § 513.

Jump to MPEP Source · 37 CFR 1.10Priority Mail ExpressCertificate of Mailing and TransmissionPCT International Application Filing
Topic

Period for Reply (37 CFR 1.134)

2 rules
MPEP GuidanceRequiredAlways
[mpep-1834-3c785dfe96636a1a68e129dc]
Invitation to Remediate Non-Compliance Within Time Limit
Note:
If the applicant fails to meet the requirements in paragraph (a), they will be given an invitation to remedy the omission within a fixed time limit, which must be at least 10 days and no more than one month from the mailing of the invitation.

(b) If the requirements provided for in paragraph (a) are not complied with, the applicant shall be informed as to the non-compliance and invited to remedy the omission within a time limit fixed in the invitation. The time limit so fixed shall be reasonable in the circumstances; even where the time limit so fixed expires later than the time limit applying to the furnishing of the paper (or even if the latter time limit has already expired), it shall not be less than 10 days and not more than one month from the mailing of the invitation. If the omission is remedied within the time limit fixed in the invitation, the omission shall be disregarded; otherwise, the applicant shall be informed that the paper has been disregarded.

Jump to MPEP SourcePeriod for Reply (37 CFR 1.134)Signature RequirementsLate Payment and Reinstatement
MPEP GuidanceRequiredAlways
[mpep-1834-927aa4f2687c70242f6313b6]
Omission Must Be Remedied Within Time Limit
Note:
If an omission is corrected within the time limit specified in the invitation, it will be disregarded; otherwise, the applicant will be informed that the paper has been disregarded.

(b) If the requirements provided for in paragraph (a) are not complied with, the applicant shall be informed as to the non-compliance and invited to remedy the omission within a time limit fixed in the invitation. The time limit so fixed shall be reasonable in the circumstances; even where the time limit so fixed expires later than the time limit applying to the furnishing of the paper (or even if the latter time limit has already expired), it shall not be less than 10 days and not more than one month from the mailing of the invitation. If the omission is remedied within the time limit fixed in the invitation, the omission shall be disregarded; otherwise, the applicant shall be informed that the paper has been disregarded.

Jump to MPEP SourcePeriod for Reply (37 CFR 1.134)Signature RequirementsLate Payment and Reinstatement
Topic

International Searching Authority (ISA)

2 rules
MPEP GuidanceRequiredAlways
[mpep-1834-48d4c3b19e78cf564f5d1597]
Letters and Documents Must Match Application Language
Note:
Letters and documents submitted to the International Searching Authority or the International Preliminary Examining Authority must be in the same language as the international application, unless a translation has been provided.

(a) Subject to Rules 55.1 and 55.3 and to paragraph (b) of this Rule, any letter or document submitted by the applicant to the International Searching Authority or the International Preliminary Examining Authority shall be in the same language as the international application to which it relates. However, where a translation of the international application has been transmitted under Rule 23.1(b) or furnished under Rule 55.2, the language of such translation shall be used.

Jump to MPEP SourceInternational Searching Authority (ISA)International SearchPatent Cooperation Treaty
MPEP GuidancePermittedAlways
[mpep-1834-6bb440e4a8c576f9d4f781eb]
Language Use for Applicant Letters to ISA/IPPEA
Note:
An applicant's letter to the International Searching Authority or the International Preliminary Examining Authority may be in a language other than that of the international application, provided such authority authorizes its use.

(b) Any letter from the applicant to the International Searching Authority or the International Preliminary Examining Authority may be in a language other than that of the international application, provided the said Authority authorizes the use of such language.

Jump to MPEP SourceInternational Searching Authority (ISA)International SearchPatent Cooperation Treaty
Topic

Patent Cooperation Treaty

2 rules
MPEP GuidanceInformativeAlways
[mpep-1834-bf5e0edd428f4947461339ee]
Papers Must Be Accompanied By Letter Identifying Application
Note:
Applicants must ensure papers submitted to the Office are accompanied by a letter identifying the related international application. Failure to do so within the time limit results in the papers being disregarded.

If the Office finds that papers, other than the international application itself, are not accompanied by a letter identifying the international application to which they relate, or are accompanied by an unsigned letter, or are furnished in the form of an unsigned letter, it notifies the applicant and invites him or her to remedy the omission. The Office disregards the said papers or letter if the omission is not remedied within the time limit fixed in the invitation (PCT Rule 92.1(b)). If the omission has been overlooked and the paper taken into account, the omission is disregarded.

Jump to MPEP SourcePatent Cooperation TreatyRequest Content and FormSignature Requirements
MPEP GuidanceInformativeAlways
[mpep-1834-dac23b2f526ba8a541773138]
Correspondence to Common Representative or Agent Required
Note:
Correspondence must be addressed to the common representative, a appointed agent, or a special notification address as indicated.

Where there are two or more applicants who have appointed one or more common agents, correspondence will be addressed to that agent or the first-mentioned of those agents. Where no common agent has been appointed, correspondence will be addressed to the common representative (either the appointed common representative or the applicant who is considered to be the common representative (PCT Rule 90.2) at the indicated address; or, if the common representative has appointed one or more agents, to that agent or the first-mentioned of those agents; or, if the common representative has not appointed an agent but has indicated a special address for notifications, at that address.

Jump to MPEP SourcePatent Cooperation TreatyPCT International Application Filing
Topic

Priority Claim in PCT

1 rules
StatutoryInformativeAlways
[mpep-1834-73563bcf277d5ea11820982f]
Priority Mail Express Mailing Label Required for Date of Deposit
Note:
The rule requires the inclusion of a Priority Mail Express mailing label number on each paper or fee when there is a question regarding the date of deposit.

If there is a question regarding the date of deposit, the Priority Mail Express® provisions of 37 CFR 1.10(c) – (e) require, in addition to using the Priority Mail Express® Post Office to Addressee service, an indication of the Priority Mail Express® mailing label number on each paper or fee. In situations wherein the correspondence includes several papers directed to the same application (for example, Request, description, claims, abstract, drawings, and other papers) the correspondence may be submitted with a cover or transmittal letter, which should itemize the papers. The cover or transmittal letter must have the Priority Mail Express® mailing label number thereon.

Jump to MPEP Source · 37 CFR 1.10(c)Priority Claim in PCTCertificate of MailingPriority Mail Express
Topic

Article 19 Amendment Scope

1 rules
StatutoryRecommendedAlways
[mpep-1834-5b8845e95086df0b820d12b2]
Cover Letter Must Itemize Papers for Same Application
Note:
A cover or transmittal letter must be included when submitting multiple papers related to the same application, listing each document submitted.

If there is a question regarding the date of deposit, the Priority Mail Express® provisions of 37 CFR 1.10(c) – (e) require, in addition to using the Priority Mail Express® Post Office to Addressee service, an indication of the Priority Mail Express® mailing label number on each paper or fee. In situations wherein the correspondence includes several papers directed to the same application (for example, Request, description, claims, abstract, drawings, and other papers) the correspondence may be submitted with a cover or transmittal letter, which should itemize the papers. The cover or transmittal letter must have the Priority Mail Express® mailing label number thereon.

Jump to MPEP Source · 37 CFR 1.10(c)Article 19 Amendment ScopeArticle 19 Amendment TimingPCT Abstract Requirements
Topic

Article 19 Amendment Timing

1 rules
StatutoryRequiredAlways
[mpep-1834-20b0e8cd055967859217857e]
Cover or Transmittal Letter Must Include Mailing Label Number
Note:
The cover or transmittal letter for Priority Mail Express® correspondence must include the mailing label number to ensure proper tracking and handling of multiple application papers.

If there is a question regarding the date of deposit, the Priority Mail Express® provisions of 37 CFR 1.10(c) – (e) require, in addition to using the Priority Mail Express® Post Office to Addressee service, an indication of the Priority Mail Express® mailing label number on each paper or fee. In situations wherein the correspondence includes several papers directed to the same application (for example, Request, description, claims, abstract, drawings, and other papers) the correspondence may be submitted with a cover or transmittal letter, which should itemize the papers. The cover or transmittal letter must have the Priority Mail Express® mailing label number thereon.

Jump to MPEP Source · 37 CFR 1.10(c)Article 19 Amendment TimingPriority Claim in PCTPriority Mail Express
Topic

Signature Requirements

1 rules
MPEP GuidanceRequiredAlways
[mpep-1834-a7d0fdaab357630f3044d90d]
Signature Required for Letters
Note:
A letter submitted by the applicant must be signed.

(a) Any paper submitted by the applicant in the course of the international procedure provided for in the Treaty and these Regulations, other than the international application itself, shall, if not itself in the form of a letter, be accompanied by a letter identifying the international application to which it relates. The letter shall be signed by the applicant.

Jump to MPEP SourceSignature RequirementsRequest Content and FormPCT Request Form
Topic

Late Payment and Reinstatement

1 rules
MPEP GuidanceProhibitedAlways
[mpep-1834-2707ef9b267e46cff1bc53a8]
Invitation to Remedy Omission Must Have Reasonable Time Frame
Note:
The time limit for responding to an invitation to remedy an omission must be at least 10 days and no more than one month from the mailing of the invitation.

(b) If the requirements provided for in paragraph (a) are not complied with, the applicant shall be informed as to the non-compliance and invited to remedy the omission within a time limit fixed in the invitation. The time limit so fixed shall be reasonable in the circumstances; even where the time limit so fixed expires later than the time limit applying to the furnishing of the paper (or even if the latter time limit has already expired), it shall not be less than 10 days and not more than one month from the mailing of the invitation. If the omission is remedied within the time limit fixed in the invitation, the omission shall be disregarded; otherwise, the applicant shall be informed that the paper has been disregarded.

Jump to MPEP SourceLate Payment and ReinstatementPeriod for Reply (37 CFR 1.134)Signature Requirements
Topic

Signature Requirements

1 rules
MPEP GuidanceRequiredAlways
[mpep-1834-5fc7b29f1dbe537a1948f0c7]
Non-Compliance with Signature Requirements Disregarded if Paper Taken into Account
Note:
If the signature requirements provided in paragraph (a) are overlooked but the paper is still considered in the international procedure, any non-compliance shall be disregarded.

(c) Where non-compliance with the requirements provided for in paragraph (a) has been overlooked and the paper taken into account in the international procedure, the non-compliance shall be disregarded.

Jump to MPEP SourceSignature Requirements
Topic

Article 34 Amendments

1 rules
MPEP GuidanceInformativeAlways
[mpep-1834-84b30a3ddd06ead149cb2cc9]
Demand Not Required for Multiple Applicants
Note:
This rule states that the first sentence of Section 1834 does not apply to demands when an international application has two or more applicants.

Where any international application indicates two or more applicants, it shall be sufficient, for the purpose of identifying that application, to indicate, in any Form or correspondence relating to such application, the name of the applicant first named in the request. The provisions of the first sentence of this Section do not apply to the demand.

Jump to MPEP SourceArticle 34 AmendmentsDemand for Preliminary ExaminationInternational Preliminary Examination (Chapter II)
Topic

PCT International Application Filing

1 rules
MPEP GuidanceInformativeAlways
[mpep-1834-ffcdf72484daae39b1c7e6fc]
Correspondence to Common Agent Required
Note:
When multiple applicants have a common agent, all correspondence must be addressed to that agent or the first-mentioned agent.

Where there are two or more applicants who have appointed one or more common agents, correspondence will be addressed to that agent or the first-mentioned of those agents. Where no common agent has been appointed, correspondence will be addressed to the common representative (either the appointed common representative or the applicant who is considered to be the common representative (PCT Rule 90.2) at the indicated address; or, if the common representative has appointed one or more agents, to that agent or the first-mentioned of those agents; or, if the common representative has not appointed an agent but has indicated a special address for notifications, at that address.

Jump to MPEP SourcePCT International Application FilingPatent Cooperation Treaty

Citations

Primary topicCitation
Certificate of Mailing
Priority Mail Express
37 CFR § 1.10
Article 19 Amendment Scope
Article 19 Amendment Timing
Priority Claim in PCT
37 CFR § 1.10(c)
Certificate of Mailing37 CFR § 1.6(a)(1)
Certificate of Mailing37 CFR § 1.8
Certificate of Mailing37 CFR § 1.8(a)(2)(i)(D)
Priority Mail ExpressMPEP § 513
PCT International Application Filing
Patent Cooperation Treaty
PCT Rule 90.2
Patent Cooperation Treaty
Request Content and Form
PCT Rule 92.1(b)

Source Text from USPTO’s MPEP

This is an exact copy of the MPEP from the USPTO. It is here for your reference to see the section in context.

BlueIron Last Updated: 2025-12-31