MPEP § 1701 — Office Personnel Not To Express Opinion on Validity, Patentability, Expiration Date, or Enforceability of Patent (Annotated Rules)

§1701 Office Personnel Not To Express Opinion on Validity, Patentability, Expiration Date, or Enforceability of Patent

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

This page consolidates and annotates all enforceable requirements under MPEP § 1701, 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.

Office Personnel Not To Express Opinion on Validity, Patentability, Expiration Date, or Enforceability of Patent

This section addresses Office Personnel Not To Express Opinion on Validity, Patentability, Expiration Date, or Enforceability of Patent. Primary authority: 35 U.S.C. 282, 37 CFR 104.1, and 37 CFR 104.21. Contains: 1 requirement, 1 prohibition, 4 guidance statements, 2 permissions, and 3 other statements.

Key Rules

Topic

Determining Expiration Date

15 rules
StatutoryInformativeAlways
[mpep-1701-ad5f7abdc88814f5aa3e1771]
Requirement for Determining Expiration Date During Examination
Note:
USPTO employees must determine the expiration date of a patent during examination of a non-reissue patent application.

Every patent is presumed to be valid. See 35 U.S.C. 282, first sentence. Public policy demands that every employee of the United States Patent and Trademark Office (USPTO) refuse to express to any person any opinion as to the validity or invalidity of, or the patentability or unpatentability of any claim in any U.S. patent or the expiration date of any patent, except to the extent necessary to carry out (A) an examination of a non-reissue patent application where determination of the expiration date of a patent is necessary to conduct examination of the non-reissue patent application,

Jump to MPEP SourceDetermining Expiration DateReissue Patent TermStatutory Authority for Examination
StatutoryInformativeAlways
[mpep-1701-94d259ade1153cdeee54ed89]
Court Determines Patent Validity
Note:
Patent validity must be determined by a court, not USPTO personnel. No employee may express opinions on patent validity or enforceability.

The question of validity or invalidity is otherwise exclusively a matter to be determined by a court. Likewise, the question of enforceability or unenforceability is exclusively a matter to be determined by a court. Members of the patent examining corps are cautioned to be especially wary of any inquiry from any person outside the USPTO, including an employee of another U.S. government agency, the answer to which might indicate that a particular patent should not have issued. No USPTO employee may pursue a bounty offered by a private sector source for identifying prior art. The acceptance of payments from outside sources for prior art search activities may subject the employee to administrative disciplinary action.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryInformativeAlways
[mpep-1701-844f620ba267f24e16397be7]
Court Determines Enforceability of Patent
Note:
The enforceability of a patent is exclusively determined by a court, as per the rule.

The question of validity or invalidity is otherwise exclusively a matter to be determined by a court. Likewise, the question of enforceability or unenforceability is exclusively a matter to be determined by a court. Members of the patent examining corps are cautioned to be especially wary of any inquiry from any person outside the USPTO, including an employee of another U.S. government agency, the answer to which might indicate that a particular patent should not have issued. No USPTO employee may pursue a bounty offered by a private sector source for identifying prior art. The acceptance of payments from outside sources for prior art search activities may subject the employee to administrative disciplinary action.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryRecommendedAlways
[mpep-1701-298fef0e91bb72dcb6e15c2e]
USPTO Examining Corps Must Avoid External Inquiries Indicating Invalid Patents
Note:
Members of the USPTO examining corps are advised to avoid responding to external inquiries that could suggest a patent should not have been issued.

The question of validity or invalidity is otherwise exclusively a matter to be determined by a court. Likewise, the question of enforceability or unenforceability is exclusively a matter to be determined by a court. Members of the patent examining corps are cautioned to be especially wary of any inquiry from any person outside the USPTO, including an employee of another U.S. government agency, the answer to which might indicate that a particular patent should not have issued. No USPTO employee may pursue a bounty offered by a private sector source for identifying prior art. The acceptance of payments from outside sources for prior art search activities may subject the employee to administrative disciplinary action.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryPermittedAlways
[mpep-1701-15f10733f6bf39dbe472da76]
USPTO Employees Cannot Pursue Private Sector Bounties for Identifying Prior Art
Note:
This rule prohibits USPTO employees from accepting bounties offered by private sector sources to identify prior art, subjecting them to administrative disciplinary action if they do so.

The question of validity or invalidity is otherwise exclusively a matter to be determined by a court. Likewise, the question of enforceability or unenforceability is exclusively a matter to be determined by a court. Members of the patent examining corps are cautioned to be especially wary of any inquiry from any person outside the USPTO, including an employee of another U.S. government agency, the answer to which might indicate that a particular patent should not have issued. No USPTO employee may pursue a bounty offered by a private sector source for identifying prior art. The acceptance of payments from outside sources for prior art search activities may subject the employee to administrative disciplinary action.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryPermittedAlways
[mpep-1701-9caf746479b8db3276a30012]
Payments for Prior Art Searches Prohibited
Note:
USPTO employees are not permitted to accept payments from outside sources for prior art search activities, which may result in administrative disciplinary action.

The question of validity or invalidity is otherwise exclusively a matter to be determined by a court. Likewise, the question of enforceability or unenforceability is exclusively a matter to be determined by a court. Members of the patent examining corps are cautioned to be especially wary of any inquiry from any person outside the USPTO, including an employee of another U.S. government agency, the answer to which might indicate that a particular patent should not have issued. No USPTO employee may pursue a bounty offered by a private sector source for identifying prior art. The acceptance of payments from outside sources for prior art search activities may subject the employee to administrative disciplinary action.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryPermittedAlways
[mpep-1701-f5ded529afeda4c7686de6a7]
Factors Affecting Patent Term Expiration
Note:
Office employees must not provide opinions on specific patent expiration dates but should use the USPTO's patent term calculator as a resource.

Office employees may provide factual information regarding the calculation of patent term in general (i.e., a design patent term is 15 years-from-grant if the underlying design patent application was filed on or after May 13, 2015, and 14 years-from-grant if the design application was filed earlier). However, office employees should refuse to provide a determination or express an opinion addressing any patent owner or public inquiries as to a specific patent's expiration date, except as provided above in items A-H. A number of factors may affect calculation of a patent term expiration date, both pre- and post-issuance, that may create difficulty in accurately calculating the term of a patent. In the event of any inquiries, the USPTO has provided a downloadable patent term calculator as a resource to help the public estimate the expiration date of a patent at www.uspto.gov/patent /laws-and-regulations/ patent-term-calculator. See also MPEP § 2701.

Jump to MPEP SourceDetermining Expiration DateDesign Patent TermPatent Term Expiration
StatutoryInformativeAlways
[mpep-1701-bc6e0c575266ff41dca8bf65]
Public Can Use Patent Term Calculator to Estimate Expiration Dates
Note:
USPTO provides a downloadable patent term calculator for the public to estimate the expiration date of a patent, aligning with MPEP § 2701.

Office employees may provide factual information regarding the calculation of patent term in general (i.e., a design patent term is 15 years-from-grant if the underlying design patent application was filed on or after May 13, 2015, and 14 years-from-grant if the design application was filed earlier). However, office employees should refuse to provide a determination or express an opinion addressing any patent owner or public inquiries as to a specific patent's expiration date, except as provided above in items A-H. A number of factors may affect calculation of a patent term expiration date, both pre- and post-issuance, that may create difficulty in accurately calculating the term of a patent. In the event of any inquiries, the USPTO has provided a downloadable patent term calculator as a resource to help the public estimate the expiration date of a patent at www.uspto.gov/patent /laws-and-regulations/ patent-term-calculator. See also MPEP § 2701.

Jump to MPEP SourceDetermining Expiration DateDesign Patent TermPatent Term Expiration
StatutoryRecommendedAlways
[mpep-1701-b184a84c72e95e25db231652]
Inquire About US Patent Existence Before Searching
Note:
Examiners must check if an invention is already patented in the US before conducting a field of search. If it has been patented, no search should be suggested.

When a field of search for an invention is requested, examiners should routinely inquire whether the invention has been patented in the United States. If the invention has been patented, no field of search should be suggested.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryRecommendedAlways
[mpep-1701-edab2f0320cddd493e8d25ac]
No Field of Search for Patented Invention
Note:
Examiners should not suggest a field of search if the invention has already been patented.

When a field of search for an invention is requested, examiners should routinely inquire whether the invention has been patented in the United States. If the invention has been patented, no field of search should be suggested.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryRecommendedAlways
[mpep-1701-3b6012d373170308beb9867d]
Patent Examiner Silence on Examination Considerations
Note:
Patent examiners must not discuss whether specific references were considered during examination or how claims would have been allowed if different evidence was used.

Employees of the USPTO, particularly patent examiners who examined an application which matured into a patent or a reissued patent or who conducted a reexamination proceeding, should not discuss or answer inquiries from any person outside the USPTO as to whether or not a certain reference or other particular evidence was considered during the examination or proceeding and whether a claim would have been allowed over that reference or other evidence had it been considered during the examination or proceeding. Likewise, employees are cautioned against answering any inquiry concerning any entry in the patent or reexamination file, including the extent of the field of search and any entry relating thereto. The record of the file of a patent or reexamination proceeding must speak for itself.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryInformativeAlways
[mpep-1701-48885c61acf2ddcf7d487ae2]
Employees Must Not Discuss Patent File Entries
Note:
USPTO employees are prohibited from answering inquiries about entries in patent or reexamination files, including the extent of the field of search.

Employees of the USPTO, particularly patent examiners who examined an application which matured into a patent or a reissued patent or who conducted a reexamination proceeding, should not discuss or answer inquiries from any person outside the USPTO as to whether or not a certain reference or other particular evidence was considered during the examination or proceeding and whether a claim would have been allowed over that reference or other evidence had it been considered during the examination or proceeding. Likewise, employees are cautioned against answering any inquiry concerning any entry in the patent or reexamination file, including the extent of the field of search and any entry relating thereto. The record of the file of a patent or reexamination proceeding must speak for itself.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryRequiredAlways
[mpep-1701-0a3143e24bbf83ae1d1fffc5]
Record of File Must Speak for Itself
Note:
Employees must not discuss whether specific evidence was considered during patent examination or reexamination, as the file record should be self-explanatory.

Employees of the USPTO, particularly patent examiners who examined an application which matured into a patent or a reissued patent or who conducted a reexamination proceeding, should not discuss or answer inquiries from any person outside the USPTO as to whether or not a certain reference or other particular evidence was considered during the examination or proceeding and whether a claim would have been allowed over that reference or other evidence had it been considered during the examination or proceeding. Likewise, employees are cautioned against answering any inquiry concerning any entry in the patent or reexamination file, including the extent of the field of search and any entry relating thereto. The record of the file of a patent or reexamination proceeding must speak for itself.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryProhibitedAlways
[mpep-1701-b7786d38daad61a0a67772d7]
Inquiries to Patent Examiners Prohibited
Note:
Practitioners must not ask members of the patent examining corps any improper questions. Refusal to answer public inquiries on these matters is not discourteous and should not imply an opinion on validity, patentability, or enforceability.

Practitioners shall not make improper inquiries of members of the patent examining corps. Inquiries from members of the public relating to the matters discussed above must out of necessity be refused and such refusal should not be considered discourteous or an expression of opinion as to validity, patentability or enforceability.

Jump to MPEP SourceDetermining Expiration DatePatent Term ExpirationPatent Term
StatutoryInformativeAlways
[mpep-1701-2242a693e5aed00019a80954]
Definitions and Exceptions for Expiration Date Determination
Note:
This rule requires that the definitions from 37 CFR 104.1 and exceptions in 37 CFR 104.21 apply to determining the expiration date of a patent.

The definitions set forth in 37 CFR 104.1 and the exceptions in 37 CFR 104.21 are applicable to this section.

Jump to MPEP Source · 37 CFR 104.1Determining Expiration DatePatent Term ExpirationPatent Term
Topic

Notice of Expiration

1 rules
StatutoryInformativeAlways
[mpep-1701-79cafabe4b174b2a2551f3b4]
USPTO Employees Must Not Express Opinions on Patent Validity
Note:
USPTO employees are required to refrain from stating opinions about the validity, patentability, or expiration date of patents unless necessary for specific official actions.
Every patent is presumed to be valid. See 35 U.S.C. 282, first sentence. Public policy demands that every employee of the United States Patent and Trademark Office (USPTO) refuse to express to any person any opinion as to the validity or invalidity of, or the patentability or unpatentability of any claim in any U.S. patent or the expiration date of any patent, except to the extent necessary to carry out:
  • (A) an examination of a non-reissue patent application where determination of the expiration date of a patent is necessary to conduct examination of the non-reissue patent application,
  • (B) an examination of a reissue application of the patent,
  • (C) a supplemental examination proceeding or reexamination proceeding to reexamine the patent,
  • (D) an interference or derivation proceeding involving the patent,
  • (E) a patent term adjustment or extension under 35 U.S.C. 154 and/or 35 U.S.C. 156 where determination of the expiration date of a patent is necessary to determine the adjustment or extension,
  • (F) a notification that a patent has expired for failure to pay maintenance fee,
  • (G) a consideration of a request under the regulations (e.g., a petition) wherein determination of patent term is necessary or arises as an ancillary matter, or
  • (H) an inter partes or post-grant review of the patent.
Jump to MPEP SourceNotice of ExpirationDetermining Expiration DateReissue Patent Term
Topic

PTE Determination Procedure

1 rules
StatutoryInformativeAlways
[mpep-1701-d9a6970fe6157b8be3095fe7]
Requirement for Patent Term Extension Determination
Note:
Employees must determine patent term adjustments or extensions under specific conditions, but not express opinions on patent validity or expiration dates.

Every patent is presumed to be valid. See 35 U.S.C. 282, first sentence. Public policy demands that every employee of the United States Patent and Trademark Office (USPTO) refuse to express to any person any opinion as to the validity or invalidity of, or the patentability or unpatentability of any claim in any U.S. patent or the expiration date of any patent, except to the extent necessary to carry out:

(E) a patent term adjustment or extension under 35 U.S.C. 154 and/or 35 U.S.C. 156 where determination of the expiration date of a patent is necessary to determine the adjustment or extension,

Jump to MPEP SourcePTE Determination ProcedureDetermining Expiration DatePatent Term Extension
Topic

Term Lapse for Maintenance Fee

1 rules
StatutoryInformativeAlways
[mpep-1701-d2f1d318043dac1e841c5338]
Notification Requirement for Maintenance Fee Lapse
Note:
USPTO employees must notify when a patent expires due to failure to pay maintenance fees, but cannot express opinions on patent validity or expiration dates otherwise.

Every patent is presumed to be valid. See 35 U.S.C. 282, first sentence. Public policy demands that every employee of the United States Patent and Trademark Office (USPTO) refuse to express to any person any opinion as to the validity or invalidity of, or the patentability or unpatentability of any claim in any U.S. patent or the expiration date of any patent, except to the extent necessary to carry out:

(F) a notification that a patent has expired for failure to pay maintenance fee,

Jump to MPEP SourceTerm Lapse for Maintenance FeePost-Issuance & Maintenance FeesPatent Expiration for Nonpayment
Topic

15-Year Term from Grant

1 rules
StatutoryRecommendedAlways
[mpep-1701-4546e19662873a35eea7b5f5]
Office Employees Must Provide General Information on Design Patent Terms
Note:
Office employees can provide general information about design patent terms but must not give opinions on specific patents' expiration dates.

Office employees may provide factual information regarding the calculation of patent term in general (i.e., a design patent term is 15 years-from-grant if the underlying design patent application was filed on or after May 13, 2015, and 14 years-from-grant if the design application was filed earlier). However, office employees should refuse to provide a determination or express an opinion addressing any patent owner or public inquiries as to a specific patent's expiration date, except as provided above in items A-H. A number of factors may affect calculation of a patent term expiration date, both pre- and post-issuance, that may create difficulty in accurately calculating the term of a patent. In the event of any inquiries, the USPTO has provided a downloadable patent term calculator as a resource to help the public estimate the expiration date of a patent at www.uspto.gov/patent /laws-and-regulations/ patent-term-calculator. See also MPEP § 2701.

Jump to MPEP Source15-Year Term from GrantDetermining Expiration DateDesign Patent Term

Citations

Primary topicCitation
Notice of Expiration
PTE Determination Procedure
35 U.S.C. § 154
Notice of Expiration
PTE Determination Procedure
35 U.S.C. § 156
Determining Expiration Date
Notice of Expiration
PTE Determination Procedure
Term Lapse for Maintenance Fee
35 U.S.C. § 282
Determining Expiration Date37 CFR § 104.1
Determining Expiration Date37 CFR § 104.21
15-Year Term from Grant
Determining Expiration Date
MPEP § 2701

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