MPEP § 2304.04(b) — Requiring a Claim (Annotated Rules)

§2304.04(b) Requiring a Claim

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

This page consolidates and annotates all enforceable requirements under MPEP § 2304.04(b), 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.

Requiring a Claim

This section addresses Requiring a Claim. Primary authority: 35 U.S.C. 132(a), 35 U.S.C. 132, and 35 U.S.C. 102(b). Contains: 8 requirements, 1 prohibition, 4 permissions, and 8 other statements.

Key Rules

Topic

Declaration of Interference

6 rules
StatutoryProhibitedAlways
[mpep-2304-04-b-4ee5a7f57e60b271e4393569]
Claim Must Not Encompass Prior Art
Note:
The claim must not include prior art or any other barred elements to avoid invalidating the application.

Given the cost and complexity of interferences, a requirement to add a claim under 37 CFR 41.202(c) should not be lightly made. Before making the requirement, the examiner should consult with an Interference Practice Specialist (IPS). The following principles should guide the examiner in exercising discretion to make this requirement:

(B) The required claim must not encompass prior art or otherwise be barred.

Jump to MPEP Source · 37 CFR 41.202(c)Declaration of InterferenceInterference Proceedings (Pre-AIA)
StatutoryRequiredAlways
[mpep-2304-04-b-26658f587f727c9ccc0aefe9]
Claim Not Required When Applicant Denies Invention
Note:
A claim should not be required if the applicant explicitly states that the commonly described subject matter is not their invention.

Given the cost and complexity of interferences, a requirement to add a claim under 37 CFR 41.202(c) should not be lightly made. Before making the requirement, the examiner should consult with an Interference Practice Specialist (IPS). The following principles should guide the examiner in exercising discretion to make this requirement:

(D) A claim should not be required when the applicant expressly states that the commonly described subject matter is not the applicant’s invention.

Jump to MPEP Source · 37 CFR 41.202(c)Declaration of InterferenceInterference Proceedings (Pre-AIA)
StatutoryRequiredAlways
[mpep-2304-04-b-d61d6031a47b12e1dc16b014]
Claim from Published Application Must Be Allowed Before Adding
Note:
A claim based on a published application should not be required unless the original claim has been allowed, considering the cost and complexity of interferences.

Given the cost and complexity of interferences, a requirement to add a claim under 37 CFR 41.202(c) should not be lightly made. Before making the requirement, the examiner should consult with an Interference Practice Specialist (IPS). The following principles should guide the examiner in exercising discretion to make this requirement:

(E) A claim based on a claim from a published application should not be required unless the claim from the published application has been allowed.

Jump to MPEP Source · 37 CFR 41.202(c)Declaration of InterferenceInterference Proceedings (Pre-AIA)
StatutoryRequiredAlways
[mpep-2304-04-b-997381a2411f50b523f98af6]
Required Claim Must Be Added for Interference
Note:
Applicants must add a required claim under 37 CFR 41.202(c) when directed by the examiner, or face losing priority on that claim and related subject matter.

If required to add a claim under 37 CFR 41.202(c), the applicant must do so. Refusal to add a required claim will operate as a concession of priority for the subject matter of the required claim. The applicant would then be barred from claiming, not only the subject matter of the required claim, but any subject matter that would have been anticipated or rendered obvious if the required claim were treated as prior art. See In re Ogiue, 517 F.2d 1382, 1390, 186 USPQ 227, 235 (CCPA 1975).

Jump to MPEP Source · 37 CFR 41.202(c)Declaration of InterferenceInterference Proceedings (Pre-AIA)Obviousness
StatutoryRequiredAlways
[mpep-2304-04-b-719bb9377f54d79f24fca212]
Refusal to Add Required Claim Concedes Priority
Note:
If an applicant refuses to add a required claim, it is considered a concession of priority for the subject matter of that claim and any related subject matter.

If required to add a claim under 37 CFR 41.202(c), the applicant must do so. Refusal to add a required claim will operate as a concession of priority for the subject matter of the required claim. The applicant would then be barred from claiming, not only the subject matter of the required claim, but any subject matter that would have been anticipated or rendered obvious if the required claim were treated as prior art. See In re Ogiue, 517 F.2d 1382, 1390, 186 USPQ 227, 235 (CCPA 1975).

Jump to MPEP Source · 37 CFR 41.202(c)Declaration of InterferenceInterference Proceedings (Pre-AIA)Obviousness
StatutoryInformativeAlways
[mpep-2304-04-b-60e2a975a04f6daebaace6d5]
Required Claim Must Be Added to Provoke Interference
Note:
If an applicant refuses to add a required claim, it is considered a concession of priority and bars claiming the subject matter of the required claim and any anticipated or obvious subject matter.

If required to add a claim under 37 CFR 41.202(c), the applicant must do so. Refusal to add a required claim will operate as a concession of priority for the subject matter of the required claim. The applicant would then be barred from claiming, not only the subject matter of the required claim, but any subject matter that would have been anticipated or rendered obvious if the required claim were treated as prior art. See In re Ogiue, 517 F.2d 1382, 1390, 186 USPQ 227, 235 (CCPA 1975).

Jump to MPEP Source · 37 CFR 41.202(c)Declaration of InterferenceInterference Proceedings (Pre-AIA)Obviousness
Topic

35 U.S.C. 112 – Disclosure Requirements

6 rules
StatutoryRequiredAlways
[mpep-2304-04-b-64559555d49ed1547e42873e]
Claims Must Be Supported by Description
Note:
The application must provide adequate support under 35 U.S.C. 112(a) for the subject matter of the required claim.

Given the cost and complexity of interferences, a requirement to add a claim under 37 CFR 41.202(c) should not be lightly made. Before making the requirement, the examiner should consult with an Interference Practice Specialist (IPS). The following principles should guide the examiner in exercising discretion to make this requirement:

(C) The application must provide adequate support under 35 U.S.C. 112(a) for the subject matter of the required claim.

Jump to MPEP Source · 37 CFR 41.202(c)Disclosure RequirementsDeclaration of InterferenceInterference Proceedings (Pre-AIA)
StatutoryInformativeAlways
[mpep-2304-04-b-270a86d0d0792cadb5f06c1f]
Improvement to Described Work Not Requiring Interference
Note:
An application can claim an improvement to work attributed to another inventor without requiring an interference if the named inventor does not claim the original work.

An application describes work that it attributes to another who is not named as an inventor in the application (“other inventor”), but also describes and claims an improvement to that work. The other inventor has received a patent for the original work. The application may in some sense have 35 U.S.C. 112(a) support for an interfering claim to the other inventor’s work. Nevertheless, the application expressly states that the commonly described subject matter is not the invention of the inventor named in the application. No interfering claim should be required.

Jump to MPEP SourceDisclosure Requirements
StatutoryInformativeAlways
[mpep-2304-04-b-ccccc817410c066ecca683dc]
Improvement Over Other Inventor’s Work Not Subject to Interference
Note:
An application can claim an improvement over work patented by another inventor without requiring an interfering claim.

An application describes work that it attributes to another who is not named as an inventor in the application (“other inventor”), but also describes and claims an improvement to that work. The other inventor has received a patent for the original work. The application may in some sense have 35 U.S.C. 112(a) support for an interfering claim to the other inventor’s work. Nevertheless, the application expressly states that the commonly described subject matter is not the invention of the inventor named in the application. No interfering claim should be required.

Jump to MPEP SourceDisclosure Requirements
StatutoryPermittedAlways
[mpep-2304-04-b-5bc92886a0eeebca1943da82]
Written Description May Support Interfering Claim to Other Inventor’s Work
Note:
The application may include a claim that supports the other inventor's work even if it does not name them as an inventor, provided it expressly states the described subject matter is not their invention.

An application describes work that it attributes to another who is not named as an inventor in the application (“other inventor”), but also describes and claims an improvement to that work. The other inventor has received a patent for the original work. The application may in some sense have 35 U.S.C. 112(a) support for an interfering claim to the other inventor’s work. Nevertheless, the application expressly states that the commonly described subject matter is not the invention of the inventor named in the application. No interfering claim should be required.

Jump to MPEP SourceDisclosure Requirements
StatutoryInformativeAlways
[mpep-2304-04-b-bfcd52c1f1bc6c1e710cda18]
Specification Must Exclude Other Inventor’s Work
Note:
The application must specify that the commonly described subject matter is not the invention of the named inventor, even if it claims an improvement to work by another inventor who has a patent for that original work.

An application describes work that it attributes to another who is not named as an inventor in the application (“other inventor”), but also describes and claims an improvement to that work. The other inventor has received a patent for the original work. The application may in some sense have 35 U.S.C. 112(a) support for an interfering claim to the other inventor’s work. Nevertheless, the application expressly states that the commonly described subject matter is not the invention of the inventor named in the application. No interfering claim should be required.

Jump to MPEP SourceDisclosure Requirements
StatutoryRequiredAlways
[mpep-2304-04-b-aa5075f7893d4f8a752f849b]
No Interfering Claim for Described Improvement
Note:
An application describing an improvement to work patented by another inventor should not be required to claim the original work as its own invention.

An application describes work that it attributes to another who is not named as an inventor in the application (“other inventor”), but also describes and claims an improvement to that work. The other inventor has received a patent for the original work. The application may in some sense have 35 U.S.C. 112(a) support for an interfering claim to the other inventor’s work. Nevertheless, the application expressly states that the commonly described subject matter is not the invention of the inventor named in the application. No interfering claim should be required.

Jump to MPEP SourceDisclosure Requirements
Topic

35 U.S.C. 103 – Obviousness

6 rules
StatutoryInformativeAlways
[mpep-2304-04-b-8b391992ee150dc84cfbe088]
Generic Claim Does Not Require Species Claim
Note:
An application supporting a generic claim does not need to include the species claim, even if it is disclosed in the patent.

An application has support for both a generic claim G and a species claim G1. The applicant only claims the genus G. A patent discloses and claims only G1. Under the facts of this example, there is no evidence that genus G would have rendered the species G1 obvious. If for some reason the patent is not available as a reference against the application, the examiner may require the applicant to add a claim to species G1 after consulting with an IPS.

StatutoryInformativeAlways
[mpep-2304-04-b-67ef50b4b27864f40b27cbf4]
Applicant Must Claim Genus G Only
Note:
The applicant must claim the genus G, even if a species within it (G1) is disclosed in another patent.

An application has support for both a generic claim G and a species claim G1. The applicant only claims the genus G. A patent discloses and claims only G1. Under the facts of this example, there is no evidence that genus G would have rendered the species G1 obvious. If for some reason the patent is not available as a reference against the application, the examiner may require the applicant to add a claim to species G1 after consulting with an IPS.

StatutoryInformativeAlways
[mpep-2304-04-b-359eaefe2e321c68c46029be]
Species Claim Required When Only Species Disclosed
Note:
If a patent discloses and claims only a specific species (G1) within a genus (G), the applicant must include a claim to that species during examination.

An application has support for both a generic claim G and a species claim G1. The applicant only claims the genus G. A patent discloses and claims only G1. Under the facts of this example, there is no evidence that genus G would have rendered the species G1 obvious. If for some reason the patent is not available as a reference against the application, the examiner may require the applicant to add a claim to species G1 after consulting with an IPS.

StatutoryInformativeAlways
[mpep-2304-04-b-f690e8756d53a049ff759712]
Species Not Rendered Obvious by Genus
Note:
The application must claim the genus G, but there is no evidence that species G1 would have been obvious from genus G.

An application has support for both a generic claim G and a species claim G1. The applicant only claims the genus G. A patent discloses and claims only G1. Under the facts of this example, there is no evidence that genus G would have rendered the species G1 obvious. If for some reason the patent is not available as a reference against the application, the examiner may require the applicant to add a claim to species G1 after consulting with an IPS.

StatutoryPermittedAlways
[mpep-2304-04-b-a7e39af611a785625ff4cdef]
Requirement to Add Claim for Species G1 if Patent Not Available as Reference
Note:
The examiner may require the applicant to add a claim for species G1 if the patent is not available as a reference against the application, even though support exists for both genus G and species G1.

An application has support for both a generic claim G and a species claim G1. The applicant only claims the genus G. A patent discloses and claims only G1. Under the facts of this example, there is no evidence that genus G would have rendered the species G1 obvious. If for some reason the patent is not available as a reference against the application, the examiner may require the applicant to add a claim to species G1 after consulting with an IPS.

StatutoryRequiredAlways
[mpep-2304-04-b-ff6409b6566f54b05e61e779]
Required Claim Bars Future Claims
Note:
If an applicant must add a required claim, they cannot later claim any subject matter that would have been anticipated or rendered obvious by the required claim.

If required to add a claim under 37 CFR 41.202(c), the applicant must do so. Refusal to add a required claim will operate as a concession of priority for the subject matter of the required claim. The applicant would then be barred from claiming, not only the subject matter of the required claim, but any subject matter that would have been anticipated or rendered obvious if the required claim were treated as prior art. See In re Ogiue, 517 F.2d 1382, 1390, 186 USPQ 227, 235 (CCPA 1975).

Jump to MPEP Source · 37 CFR 41.202(c)ObviousnessDeclaration of InterferenceInterference Proceedings (Pre-AIA)
Topic

Interference Proceedings (Pre-AIA)

3 rules
StatutoryPermittedAlways
[mpep-2304-04-b-a2d7d5cd66f1493eff773ba1]
Requirement for Adding Claim That Does Not Interfere with Another Application or Patent
Note:
The examiner may require an applicant to add a claim that does not interfere with claims in another application or patent.

The examiner may, pursuant to 35 U.S.C. 132(a), require an applicant to add a claim that would interfere with the claim of another application or patent. For example, the requirement may be made to obtain a clearer definition of the interfering subject matter or to establish whether the applicant will pursue claims to the interfering subject matter. When the requirement is based on a published application with allowed claims or a patent, the examiner must identify the published application or the patent in making the requirement.

Jump to MPEP SourceInterference Proceedings (Pre-AIA)
StatutoryPermittedAlways
[mpep-2304-04-b-1f1864b6aafc3e9875ac6662]
Requirement for Claim to Interfere with Another Application or Patent
Note:
The examiner may require an applicant to add a claim that would interfere with another application or patent, seeking clarity on the interfering subject matter or confirming the applicant's pursuit of such claims.

The examiner may, pursuant to 35 U.S.C. 132(a), require an applicant to add a claim that would interfere with the claim of another application or patent. For example, the requirement may be made to obtain a clearer definition of the interfering subject matter or to establish whether the applicant will pursue claims to the interfering subject matter. When the requirement is based on a published application with allowed claims or a patent, the examiner must identify the published application or the patent in making the requirement.

Jump to MPEP SourceInterference Proceedings (Pre-AIA)
StatutoryRequiredAlways
[mpep-2304-04-b-decf6994936e6084c444af49]
Requirement for Identifying Published Application with Allowed Claims
Note:
The examiner must identify a published application with allowed claims when making a requirement based on it.

The examiner may, pursuant to 35 U.S.C. 132(a), require an applicant to add a claim that would interfere with the claim of another application or patent. For example, the requirement may be made to obtain a clearer definition of the interfering subject matter or to establish whether the applicant will pursue claims to the interfering subject matter. When the requirement is based on a published application with allowed claims or a patent, the examiner must identify the published application or the patent in making the requirement.

Jump to MPEP SourceInterference Proceedings (Pre-AIA)
Topic

Prior Art Under AIA 35 U.S.C. 102 (MPEP 2150-2159)

2 rules
StatutoryInformativeAlways
[mpep-2304-04-b-22e238beedd3d611090d4424]
Patent Is Pre-AIA Prior Art Against Interfering Claims
Note:
A patent serves as pre-AIA prior art against any possible interfering claims, without requiring an interfering claim to be established.

A patent is pre-AIA 35 U.S.C. 102(b) prior art against any possible interfering claim. No interfering claim should be required.

Jump to MPEP SourcePrior Art Under AIA 35 U.S.C. 102 (MPEP 2150-2159)Prior Art Under Pre-AIA 35 U.S.C. 102 (MPEP 2131-2138)AIA vs Pre-AIA 102 (MPEP 2151)
StatutoryRequiredAlways
[mpep-2304-04-b-b5418740794957a4ba418d00]
Prior Art Under AIA 35 U.S.C. 102 No Interfering Claim Required
Note:
A patent is pre-AIA 35 U.S.C. 102 prior art against any possible interfering claim, and no such claim should be required.

A patent is pre-AIA 35 U.S.C. 102(b) prior art against any possible interfering claim. No interfering claim should be required.

Jump to MPEP SourcePrior Art Under AIA 35 U.S.C. 102 (MPEP 2150-2159)Prior Art Under Pre-AIA 35 U.S.C. 102 (MPEP 2131-2138)AIA vs Pre-AIA 102 (MPEP 2151)
Topic

Assignee as Applicant Signature

2 rules
StatutoryInformativeAlways
[mpep-2304-04-b-d3cc13d4f547d3ca7b4635b9]
Claim Support Requirement After One Year
Note:
The applicant must support any new claim added to the patent more than one year after issuance, as previously not claiming the same subject matter.

The patent issued more than one year ago and the applicant did not previously have a claim to the same subject matter. Any added claim would most likely be time barred under pre-AIA 35 U.S.C. 135(b)(1). No interfering claim should be required.

Jump to MPEP SourceAssignee as Applicant SignatureApplicant and Assignee Filing Under AIAAIA vs Pre-AIA Practice
StatutoryRequiredAlways
[mpep-2304-04-b-c0c67ff1c1c7b0ce4d9cd657]
Interference Not Required for New Claims
Note:
New claims added to a patent filed over a year ago do not require interference if the applicant did not previously claim the same subject matter.

The patent issued more than one year ago and the applicant did not previously have a claim to the same subject matter. Any added claim would most likely be time barred under pre-AIA 35 U.S.C. 135(b)(1). No interfering claim should be required.

Jump to MPEP SourceAssignee as Applicant SignatureApplicant and Assignee Filing Under AIAAIA vs Pre-AIA Practice
Topic

Rejection of Claims

1 rules
StatutoryRecommendedAlways
[mpep-2304-04-b-f8c1e8fe42b51dabe43fc838]
Requirement for Interference Not to Be Easily Made
Note:
Examiners must consult an IPS before requiring a claim under 37 CFR 41.202(c) due to the cost and complexity of interferences, ensuring adherence to specific principles.
Given the cost and complexity of interferences, a requirement to add a claim under 37 CFR 41.202(c) should not be lightly made. Before making the requirement, the examiner should consult with an Interference Practice Specialist (IPS). The following principles should guide the examiner in exercising discretion to make this requirement:
  • (A) An interference should generally not be suggested if examination of the application is not otherwise completed.
  • (B) The required claim must not encompass prior art or otherwise be barred.
  • (C) The application must provide adequate support under 35 U.S.C. 112(a) for the subject matter of the required claim.
  • (D) A claim should not be required when the applicant expressly states that the commonly described subject matter is not the applicant’s invention.
  • (E) A claim based on a claim from a published application should not be required unless the claim from the published application has been allowed.
Jump to MPEP Source · 37 CFR 41.202(c)Rejection of ClaimsRejections Not Based on Prior ArtRejection on Prior Art
Topic

Statutory Authority for Examination

1 rules
StatutoryRecommendedAlways
[mpep-2304-04-b-10b461048d13e82b5a68657e]
Interference Should Not Be Suggested If Application Examination Is Not Complete
Note:
Examiners should not suggest an interference if the application examination is not otherwise completed, considering the cost and complexity of interferences.

Given the cost and complexity of interferences, a requirement to add a claim under 37 CFR 41.202(c) should not be lightly made. Before making the requirement, the examiner should consult with an Interference Practice Specialist (IPS). The following principles should guide the examiner in exercising discretion to make this requirement (A) An interference should generally not be suggested if examination of the application is not otherwise completed.

Jump to MPEP Source · 37 CFR 41.202(c)Statutory Authority for ExaminationExamination ProceduresRejection of Claims
Topic

AIA vs Pre-AIA Practice

1 rules
StatutoryInformativeAlways
[mpep-2304-04-b-79b590b68ebe4ac42c2cfa90]
Pre-AIA Claim Time Barred After Issuance
Note:
Any new claim added would most likely be time barred under pre-AIA 35 U.S.C. 135(b)(1) after the patent issued more than one year ago and no previous claim existed for the same subject matter.

The patent issued more than one year ago and the applicant did not previously have a claim to the same subject matter. Any added claim would most likely be time barred under pre-AIA 35 U.S.C. 135(b)(1). No interfering claim should be required.

Jump to MPEP SourceAIA vs Pre-AIA PracticeAssignee as Applicant SignatureApplicant and Assignee Filing Under AIA

Examiner Form Paragraphs

Examiner form paragraphs are standard language that you might see in an Office Action or communication from the USPTO. Examiners have latitude to change the form paragraphs, but you will often see this exact language.

¶ 23.04 ¶ 23.04 Requiring Applicant to Add Claim to Provoke Interference

The following allowable claim from [1] is required to be added for the purpose of an interference:

[2]

The claim must be copied exactly.

Applicant is given TWO (2) MONTHS from the mailing date of this communication to add the claim. Refusal to add a required claim will operate as a concession of priority for the subject matter of the required claim, but will not result in abandonment of this application. See 37 CFR 41.202(c) and MPEP § 2304.04(b) . EXTENSIONS OF THIS TIME PERIOD MAY BE GRANTED UNDER 37 CFR 1.136(a) but in no case can any extension carry the date for reply to this letter beyond the maximum period of SIX MONTHS set by statute ( 35 U.S.C. 133 ). If the interference would be with a patent, applicant must also comply with 37 CFR 41.202(a)(2) to (a)(6) .

Citations

Primary topicCitation
Prior Art Under AIA 35 U.S.C. 102 (MPEP 2150-2159)35 U.S.C. § 102(b)
35 U.S.C. 112 – Disclosure Requirements
Rejection of Claims
35 U.S.C. § 112(a)
Interference Proceedings (Pre-AIA)35 U.S.C. § 132(a)
AIA vs Pre-AIA Practice
Assignee as Applicant Signature
35 U.S.C. § 135(b)(1)
35 U.S.C. 103 – Obviousness
35 U.S.C. 112 – Disclosure Requirements
Declaration of Interference
Rejection of Claims
Statutory Authority for Examination
37 CFR § 41.202(c)
Form Paragraph § 23.04
35 U.S.C. 103 – Obviousness
Declaration of Interference
In re Ogiue, 517 F.2d 1382, 1390, 186 USPQ 227, 235 (CCPA 1975)

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