MPEP § 216.01 — Perfecting Claim for Priority Under 35 U.S.C. 119(a)-(d) or (f) After Issuance of a Patent (Annotated Rules)

§216.01 Perfecting Claim for Priority Under 35 U.S.C. 119(a)-(d) or (f) After Issuance of a Patent

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

This page consolidates and annotates all enforceable requirements under MPEP § 216.01, 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.

Perfecting Claim for Priority Under 35 U.S.C. 119(a)-(d) or (f) After Issuance of a Patent

This section addresses Perfecting Claim for Priority Under 35 U.S.C. 119(a)-(d) or (f) After Issuance of a Patent. Primary authority: 35 U.S.C. 255, 35 U.S.C. 120, and 35 U.S.C. 119(a). Contains: 4 requirements, 1 prohibition, 5 permissions, and 1 other statement.

Key Rules

Topic

AIA Effective Dates

4 rules
StatutoryRequiredAlways
[mpep-216-01-af04d8e21de424dbacbae314]
Petition for Unintentionally Delayed Priority Claim Requires Further Examination
Note:
A petition to accept an unintentionally delayed priority claim should not be granted if further examination would be required, such as when the foreign application has a pre-March 16, 2013 filing date and the patent was examined under AIA FITF provisions.

Except in certain situations, a certificate of correction can generally be used to perfect a claim to foreign priority where a petition under 37 CFR 1.55(e) to accept an unintentionally delayed priority claim is filed with a request for a certificate of correction in an issued patent. See MPEP § 214.02 for a discussion of the requirements for the petition. In situations where further examination would be required, the petition should not be granted. For example, further examination would be required where grant of the petition would cause the patent to be subject to a different statutory framework, e.g., where the foreign application has a pre-March 16, 2013 filing date in a patent that was examined under the first inventor to file (FITF) provisions of the AIA. In such situations, the filing of a reissue application with a petition for an unintentionally delayed priority claim would be required.

Jump to MPEP Source · 37 CFR 1.55(e)AIA Effective DatesKey Changes Under AIAPetition for Delayed Priority Claim
StatutoryRequiredAlways
[mpep-216-01-6f6e3eaadde61e176e4969a4]
Petition Grant Requires Further Examination if Causing Different Statutory Framework
Note:
A petition to accept an unintentionally delayed foreign priority claim cannot be granted without further examination, especially when it would cause the patent to fall under a different statutory framework like pre-AIA rules.

Except in certain situations, a certificate of correction can generally be used to perfect a claim to foreign priority where a petition under 37 CFR 1.55(e) to accept an unintentionally delayed priority claim is filed with a request for a certificate of correction in an issued patent. See MPEP § 214.02 for a discussion of the requirements for the petition. In situations where further examination would be required, the petition should not be granted. For example, further examination would be required where grant of the petition would cause the patent to be subject to a different statutory framework, e.g., where the foreign application has a pre-March 16, 2013 filing date in a patent that was examined under the first inventor to file (FITF) provisions of the AIA. In such situations, the filing of a reissue application with a petition for an unintentionally delayed priority claim would be required.

Jump to MPEP Source · 37 CFR 1.55(e)AIA Effective DatesKey Changes Under AIAAIA Overview and Effective Dates
StatutoryPermittedAlways
[mpep-216-01-60119872c5d5855e4a5357a4]
Claim to Foreign Priority Benefits Through Reissue
Note:
A claim to foreign priority benefits can be perfected through a reissue application if the original requirements were not met, or further examination is needed.

As an alternative to requesting a certificate of correction, a claim to foreign priority benefits can be perfected by way of a reissue application in accordance with the rationale set forth in Brenner v. State of Israel, 400 F.2d 789, 158 USPQ 584 (D.C. Cir. 1968). In circumstances where a claim to foreign priority benefits cannot be perfected via a certificate of correction because the requirements of 35 U.S.C. 119(a) – (d) or (f) had not been satisfied in the patented application, or its parent, prior to issuance, and the requirements of 37 CFR 1.55 are not met, or where the correction sought would require further examination (e.g., where the foreign application has a pre-March 16, 2013 filing date in a patent that was examined under the first inventor to file (FITF) provisions of the AIA) the claim to foreign priority benefits can be perfected only by way of a reissue application. Note that 37 CFR 1.55(h) provides that the requirement for a certified copy of the foreign application will be considered satisfied in a reissue application if the patent for which reissue is sought satisfies the requirement for a certified copy of the foreign application and such patent is identified as containing a certified copy of the foreign application.

Jump to MPEP Source · 37 CFR 1.55AIA Effective DatesKey Changes Under AIAAIA Overview and Effective Dates
StatutoryProhibitedAlways
[mpep-216-01-b0a6e341feb7988137187eca]
Claim to Foreign Priority Benefits Must Be Perfected by Reissue Application
Note:
When the requirements for foreign priority cannot be met via a certificate of correction, a reissue application is required to perfect the claim.

As an alternative to requesting a certificate of correction, a claim to foreign priority benefits can be perfected by way of a reissue application in accordance with the rationale set forth in Brenner v. State of Israel, 400 F.2d 789, 158 USPQ 584 (D.C. Cir. 1968). In circumstances where a claim to foreign priority benefits cannot be perfected via a certificate of correction because the requirements of 35 U.S.C. 119(a) – (d) or (f) had not been satisfied in the patented application, or its parent, prior to issuance, and the requirements of 37 CFR 1.55 are not met, or where the correction sought would require further examination (e.g., where the foreign application has a pre-March 16, 2013 filing date in a patent that was examined under the first inventor to file (FITF) provisions of the AIA) the claim to foreign priority benefits can be perfected only by way of a reissue application. Note that 37 CFR 1.55(h) provides that the requirement for a certified copy of the foreign application will be considered satisfied in a reissue application if the patent for which reissue is sought satisfies the requirement for a certified copy of the foreign application and such patent is identified as containing a certified copy of the foreign application.

Jump to MPEP Source · 37 CFR 1.55AIA Effective DatesKey Changes Under AIAAIA Overview and Effective Dates
Topic

Foreign Priority Claims

3 rules
StatutoryPermittedAlways
[mpep-216-01-16d3557bf3dc6c740cb9fddd]
Cure Foreign Priority Claim After Issuance Via Certificate of Correction or Reissue Application
Note:
The failure to claim foreign priority before patent issuance can be corrected using a certificate of correction under 35 U.S.C. 255 and 37 CFR 1.323, provided the requirements of 37 CFR 1.55 are met, or by filing a reissue application.

The failure to perfect a claim to foreign priority prior to issuance of the patent may be cured via a certificate of correction under 35 U.S.C. 255 and 37 CFR 1.323, provided the requirements of 37 CFR 1.55 are met, or by filing a reissue application.

Jump to MPEP Source · 37 CFR 1.323Foreign Priority ClaimsReissue Application FilingPriority and Benefit Claims
StatutoryPermittedAlways
[mpep-216-01-4831a7ce1a8b4678bfd04d13]
Request to Issue Certificate of Correction for Foreign Priority Benefits
Note:
A request to issue a certificate of correction can be used to perfect a claim to foreign priority benefits after the patent has been issued.

As an example of when a request to issue a certificate of correction may be used in order to perfect a claim to foreign priority benefits, see In re Van Esdonk, 187 USPQ 671 (Comm’r Pat. 1975). In In re Van Esdonk, a claim to foreign priority benefits had not been filed in the application prior to issuance of the patent. However, the application was a continuation of an earlier application in which the requirements of 35 U.S.C. 119(a) – (d) or (f) had been satisfied. Accordingly, the Commissioner held that the “applicants’ perfection of a priority claim under 35 U.S.C. 119 in the parent application will satisfy the statute with respect to their continuation application.”

Jump to MPEP Source · 37 CFR 1.55Foreign Priority ClaimsPriority and Benefit ClaimsDomestic Benefit Claims (35 U.S.C. 120/121)
StatutoryInformativeAlways
[mpep-216-01-aef8ac6cd8813468f0fa2f83]
Claim to Foreign Priority After Patent Issuance
Note:
A claim to foreign priority benefits can be perfected in a continuation application even if not initially filed, provided the parent application satisfied 35 U.S.C. 119(a)-(d) or (f) requirements.

As an example of when a request to issue a certificate of correction may be used in order to perfect a claim to foreign priority benefits, see In re Van Esdonk, 187 USPQ 671 (Comm’r Pat. 1975). In In re Van Esdonk, a claim to foreign priority benefits had not been filed in the application prior to issuance of the patent. However, the application was a continuation of an earlier application in which the requirements of 35 U.S.C. 119(a) – (d) or (f) had been satisfied. Accordingly, the Commissioner held that the “applicants’ perfection of a priority claim under 35 U.S.C. 119 in the parent application will satisfy the statute with respect to their continuation application.”

Jump to MPEP Source · 37 CFR 1.55Foreign Priority ClaimsPriority and Benefit ClaimsDomestic Benefit Claims (35 U.S.C. 120/121)
Topic

Domestic Benefit Claims (35 U.S.C. 120/121)

3 rules
StatutoryInformativeAlways
[mpep-216-01-4d2e8e4074c7fb33bfe3d35a]
Priority Claim for Continuation Application
Note:
Perfection of a priority claim in the parent application satisfies the statute with respect to the continuation application.

As an example of when a request to issue a certificate of correction may be used in order to perfect a claim to foreign priority benefits, see In re Van Esdonk, 187 USPQ 671 (Comm’r Pat. 1975). In In re Van Esdonk, a claim to foreign priority benefits had not been filed in the application prior to issuance of the patent. However, the application was a continuation of an earlier application in which the requirements of 35 U.S.C. 119(a) – (d) or (f) had been satisfied. Accordingly, the Commissioner held that the “applicants’ perfection of a priority claim under 35 U.S.C. 119 in the parent application will satisfy the statute with respect to their continuation application.”

Jump to MPEP Source · 37 CFR 1.55Domestic Benefit Claims (35 U.S.C. 120/121)Priority and Benefit ClaimsForeign Priority Claims
StatutoryInformativeAlways
[mpep-216-01-ef5977b9cebfe85aa92c4633]
Claim to Foreign Priority in Continuing Application Constitutes Affirmation of Prior Expression for Subject Matter Commonality
Note:
A claim to foreign priority benefits in a continuing application, where the claim has been perfected in the parent application, is essentially an affirmation of the applicant’s previously expressed desire for subject matter commonality under 35 U.S.C. 119(a)-(d) or (f).

Although In re Van Esdonk involved the patent of a continuation application filed under former 37 CFR 1.60, it is proper to apply the holding of that case in similar factual circumstances to any patented application having benefits under 35 U.S.C. 120. This is primarily because a claim to foreign priority benefits in a continuing application, where the claim has been perfected in the parent application, constitutes in essence a mere affirmation of the applicant’s previously expressed desire to receive benefits under 35 U.S.C. 119(a) – (d) or (f) for subject matter common to the foreign, parent, and continuing applications.

Jump to MPEP Source · 37 CFR 1.60Domestic Benefit Claims (35 U.S.C. 120/121)Foreign Priority ClaimsPriority and Benefit Claims
StatutoryPermittedAlways
[mpep-216-01-c481f66ed40e622497068037]
Requirement for Perfecting Foreign Priority Claim After Patent Issuance
Note:
A certificate of correction may be requested if the foreign priority requirements were met before patent issuance and no further examination is needed.

In summary, a certificate of correction under 35 U.S.C. 255 and 37 CFR 1.323 may be requested and issued in order to perfect a claim for foreign priority benefit in a patent if (1) the requirements of 35 U.S.C. 119(a) – (d) or (f) had been satisfied in the patented application or in a parent application prior to issuance of the patent, (2) the requirements of 37 CFR 1.55 are met, and (3) the correction sought would not require further examination.

Jump to MPEP Source · 37 CFR 1.323Domestic Benefit Claims (35 U.S.C. 120/121)Foreign Priority ClaimsPriority and Benefit Claims
Topic

Petition for Delayed Priority Claim

2 rules
StatutoryPermittedAlways
[mpep-216-01-5872d752830d0bc13b4d9ab2]
Petition for Unintentionally Delayed Foreign Priority Claim
Note:
A petition under 37 CFR 1.55(e) to accept an unintentionally delayed foreign priority claim can be used with a request for a certificate of correction in an issued patent, subject to certain conditions.

Except in certain situations, a certificate of correction can generally be used to perfect a claim to foreign priority where a petition under 37 CFR 1.55(e) to accept an unintentionally delayed priority claim is filed with a request for a certificate of correction in an issued patent. See MPEP § 214.02 for a discussion of the requirements for the petition. In situations where further examination would be required, the petition should not be granted. For example, further examination would be required where grant of the petition would cause the patent to be subject to a different statutory framework, e.g., where the foreign application has a pre-March 16, 2013 filing date in a patent that was examined under the first inventor to file (FITF) provisions of the AIA. In such situations, the filing of a reissue application with a petition for an unintentionally delayed priority claim would be required.

Jump to MPEP Source · 37 CFR 1.55(e)Petition for Delayed Priority ClaimUnintentional Delay StandardDelayed Benefit/Priority Claims
StatutoryRequiredAlways
[mpep-216-01-9a91011a0a219e284f625904]
Reissue Application for Unintentionally Delayed Priority Claim
Note:
When further examination is required due to an unintentionally delayed priority claim, a reissue application must be filed along with the petition.

Except in certain situations, a certificate of correction can generally be used to perfect a claim to foreign priority where a petition under 37 CFR 1.55(e) to accept an unintentionally delayed priority claim is filed with a request for a certificate of correction in an issued patent. See MPEP § 214.02 for a discussion of the requirements for the petition. In situations where further examination would be required, the petition should not be granted. For example, further examination would be required where grant of the petition would cause the patent to be subject to a different statutory framework, e.g., where the foreign application has a pre-March 16, 2013 filing date in a patent that was examined under the first inventor to file (FITF) provisions of the AIA. In such situations, the filing of a reissue application with a petition for an unintentionally delayed priority claim would be required.

Jump to MPEP Source · 37 CFR 1.55(e)Petition for Delayed Priority ClaimUnintentional Delay StandardDelayed Benefit/Priority Claims
Topic

Ordering Certified Copies

2 rules
StatutoryRequiredAlways
[mpep-216-01-c5321650500ffa6824fed603]
Priority Claim and Certified Copy Allowed After Patent Issuance
Note:
Allows filing of a priority claim and certified copy through petition even after patent issuance if no timely initial claim was made.

Effective May 13, 2015, 37 CFR 1.55(g) provides that the claim for priority and the certified copy of the foreign application must be filed within the pendency of the application, unless filed with a petition under 37 CFR 1.55(e), (f), or (g) as appropriate. 37 CFR 1.55(g) eliminates the need in many instances to file a reissue application in order to perfect a claim for foreign priority. Specifically,

(B) Where a priority claim under 37 CFR 1.55 was not timely made, 37 CFR 1.55(g) allows the priority claim and the certified copy required under 37 CFR 1.55 to be filed pursuant to a petition under 37 CFR 1.55(e) even if the application is not pending (e.g., a patented application) in situations where the correction sought would not require further examination.

Jump to MPEP Source · 37 CFR 1.55(g)Ordering Certified CopiesForeign Priority ClaimsCertified Copies of Documents
StatutoryPermittedAlways
[mpep-216-01-6bd2ab5d35f39197e7f946e3]
Requirement for Certified Copy of Foreign Application
Note:
Applicant must include a certified copy of the foreign application in a prior-filed nonprovisional application claiming benefit under 35 U.S.C. 120, 121, 365(c), or 386(c) to satisfy the requirement for a certified copy in a subsequent application.

37 CFR 1.55(h) provides that the requirement for a certified copy of the foreign application will be considered satisfied in an application if a prior-filed nonprovisional application for which a benefit is claimed under 35 U.S.C. 120, 121, 365(c), or 386(c) contains a certified copy of the foreign application and the prior-filed nonprovisional application is identified as containing a certified copy of the foreign application. Thus, applicant may request a certificate of correction under 35 U.S.C. 255 and 37 CFR 1.323 where the prior-filed nonprovisional application is identified as containing a certified copy of the foreign application and where the priority claim was timely made in the application claiming benefit under 35 U.S.C. 120, 121, 365(c), or 386(c) and the certified copy of the foreign application was timely filed in the parent application.

Jump to MPEP Source · 37 CFR 1.55(h)Ordering Certified CopiesCertified Copies of DocumentsDomestic Benefit Claims (35 U.S.C. 120/121)
Topic

Design Claim Form

1 rules
StatutoryRequiredAlways
[mpep-216-01-6fd34752392e7e2d843d2c81]
Priority Claim and Certified Copy Must Be Filed During Pendency
Note:
The claim for priority and certified copy of the foreign application must be filed during the pendency of the application, unless a petition under specific conditions is filed.
Effective May 13, 2015, 37 CFR 1.55(g) provides that the claim for priority and the certified copy of the foreign application must be filed within the pendency of the application, unless filed with a petition under 37 CFR 1.55(e), (f), or (g) as appropriate. 37 CFR 1.55(g) eliminates the need in many instances to file a reissue application in order to perfect a claim for foreign priority. Specifically,
  • (A) Where the priority claim required under 37 CFR 1.55 was timely filed in the application but was not included on the patent because the requirement under 37 CFR 1.55 for a certified copy was not satisfied, the patent may be corrected to include the priority claim via a certificate of correction under 35 U.S.C. 255 and 37 CFR 1.323, accompanied by a grantable petition under 37 CFR 1.55(f) or, in the case of a design application, a grantable petition under 37 CFR 1.55(g). In this situation, a petition under 37 CFR 1.55(e) to accept an unintentionally delayed priority claim is not needed. A grantable petition under 37 CFR 1.55(f) or (g) must include the fee set forth in 37 CFR 1.17(g) and a showing of good and sufficient cause for the delay in filing the certified copy of the foreign application; and
  • (B) Where a priority claim under 37 CFR 1.55 was not timely made, 37 CFR 1.55(g) allows the priority claim and the certified copy required under 37 CFR 1.55 to be filed pursuant to a petition under 37 CFR 1.55(e) even if the application is not pending (e.g., a patented application) in situations where the correction sought would not require further examination.
Jump to MPEP Source · 37 CFR 1.55(g)Design Claim FormDesign Foreign Priority (6 Months)Foreign Priority Claim Requirements

Citations

Primary topicCitation
Domestic Benefit Claims (35 U.S.C. 120/121)
Foreign Priority Claims
35 U.S.C. § 119
AIA Effective Dates
Domestic Benefit Claims (35 U.S.C. 120/121)
Foreign Priority Claims
35 U.S.C. § 119(a)
Domestic Benefit Claims (35 U.S.C. 120/121)
Ordering Certified Copies
35 U.S.C. § 120
Design Claim Form
Domestic Benefit Claims (35 U.S.C. 120/121)
Foreign Priority Claims
Ordering Certified Copies
35 U.S.C. § 255
Design Claim Form37 CFR § 1.17(g)
Design Claim Form
Domestic Benefit Claims (35 U.S.C. 120/121)
Foreign Priority Claims
Ordering Certified Copies
37 CFR § 1.323
AIA Effective Dates
Design Claim Form
Domestic Benefit Claims (35 U.S.C. 120/121)
Foreign Priority Claims
Ordering Certified Copies
37 CFR § 1.55
AIA Effective Dates
Design Claim Form
Ordering Certified Copies
Petition for Delayed Priority Claim
37 CFR § 1.55(e)
Design Claim Form37 CFR § 1.55(f)
Design Claim Form
Ordering Certified Copies
37 CFR § 1.55(g)
AIA Effective Dates
Ordering Certified Copies
37 CFR § 1.55(h)
Domestic Benefit Claims (35 U.S.C. 120/121)37 CFR § 1.60
AIA Effective Dates
Petition for Delayed Priority Claim
MPEP § 214.02

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