MPEP § 707.05(e) — Data Used in Citing References (Annotated Rules)

§707.05(e) Data Used in Citing References

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

This page consolidates and annotates all enforceable requirements under MPEP § 707.05(e), 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.

Data Used in Citing References

This section addresses Data Used in Citing References. Primary authority: 37 CFR 1.104(d). Contains: 1 requirement, 7 guidance statements, and 6 other statements.

Key Rules

Topic

PTO-892 Notice of References Cited

8 rules
StatutoryRecommendedAlways
[mpep-707-05-e-19cf6bccfbbb83d123638f50]
Examiner Must Provide Citations on PTO-892
Note:
The examiner is required to provide citations on the Notice of References Cited form PTO-892.

37 CFR 1.104(d) (see also MPEP §§ 707.05 and 901.05(a)) requires the examiner to provide certain data when citing references. The examiner should provide the citations on the “Notice of References Cited” form PTO-892 (copy at MPEP § 707.05).

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedCitation of References (MPEP 707.05)Examiner's Action (37 CFR 1.104)
StatutoryRecommendedAlways
[mpep-707-05-e-c768c4dd0c395c934fb85939]
Non-Patent Documents Must Be Cited on PTO-892
Note:
Sufficient information must be provided to identify and locate non-patent documents for citation on the PTO-892 form.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedCitation of References (MPEP 707.05)Reference Identification Requirements
StatutoryRecommendedAlways
[mpep-707-05-e-c3a6b8f6d5aa498fbffa2b2f]
Sufficient Information for Publication Citation Required
Note:
Examiners must provide enough details to identify and locate publications cited in the PTO-892 Notice of References Cited.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedReference Identification RequirementsCitation of References (MPEP 707.05)
StatutoryInformativeAlways
[mpep-707-05-e-63dc38b2cf3806655c2a2fac]
Books on Interlibrary Loan Must Use Other Library Call Numbers
Note:
When citing books on interlibrary loan, use the call numbers from the lending library instead of STIC's.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedReference Identification RequirementsCitation of References (MPEP 707.05)
StatutoryRecommendedAlways
[mpep-707-05-e-69700b5bbcda0cc2c80b081b]
Proper Citation of Non-Patent Documents
Note:
This rule outlines how to properly cite non-patent documents, including abstracts and Alien Property Custodian publications, on the PTO-892 form.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedReference Identification RequirementsCitation of References (MPEP 707.05)
StatutoryRecommendedAlways
[mpep-707-05-e-f2b3431cb2be9eb0bd307acd]
Same Convention for Citing Articles from Periodicals
Note:
Ensure consistent citation format when referencing articles in periodicals.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedReference Identification RequirementsCitation of References (MPEP 707.05)
StatutoryRecommendedAlways
[mpep-707-05-e-fade2ce7890999fe67cdf637]
Call Number for STIC-Owned Periodicals Required
Note:
The call number must be cited for periodicals owned by the Scientific and Technical Information Center (STIC), but not for those borrowed from other libraries.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedReference Identification RequirementsCitation of References (MPEP 707.05)
StatutoryRecommendedAlways
[mpep-707-05-e-367da38d9dff6176964ba830]
Copy in Technology Center Required
Note:
If the copy relied on is located only in the Technology Center making the action, include 'Copy in Technology Center — —' to indicate its location.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)PTO-892 Notice of References CitedReference Identification RequirementsCitation of References (MPEP 707.05)
Topic

Examiner's Action (37 CFR 1.104)

2 rules
StatutoryInformativeAlways
[mpep-707-05-e-b1f0b4a70ed58e4080020dad]
Citations Required for References
Note:
The examiner must provide specific data when citing references on the Notice of References Cited form.

37 CFR 1.104(d) (see also MPEP §§ 707.05 and 901.05(a)) requires the examiner to provide certain data when citing references. The examiner should provide the citations on the “Notice of References Cited” form PTO-892 (copy at MPEP § 707.05).

Jump to MPEP Source · 37 CFR 1.104(d)Examiner's Action (37 CFR 1.104)Examination ProceduresPTO-892 Notice of References Cited
StatutoryRequiredAlways
[mpep-707-05-e-c1e515fd8f5ed745a07c3e12]
Call Number Required for Books
Note:
For books, provide the specific pages relied on along with the STIC call number as required by 37 CFR 1.104(d).

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)Examiner's Action (37 CFR 1.104)Examination ProceduresPTO-892 Notice of References Cited
Topic

Hague Agreement Overview

2 rules
StatutoryInformativeAlways
[mpep-707-05-e-397710c26f4cfa9bb7c03b8f]
International Design Registrations Do Not Get Unique Publication Numbers
Note:
When citing an international design registration, both the International Registration Number and publication date must be included as no unique publication number is assigned.

International registrations published by the World Intellectual Property Organization (WIPO) under the Hague Agreement Concerning the International Registration of Industrial Designs (also known as published international design applications) are not assigned a publication number uniquely identifying the published international registration. When citing an international registration, both the International Registration Number (referenced by INID Code 11 in the publication) and the publication date should be included. See the third item under example 5 of subsection IV below.

Jump to MPEP SourceHague Agreement OverviewBasic Hague Agreement PrinciplesInternational Design Applications
StatutoryInformativeAlways
[mpep-707-05-e-bc723f47166363f980eae5fb]
Publication Requires INID and Date for International Design Applications
Note:
When citing an international design application, both the International Registration Number and publication date must be included.

International registrations published by the World Intellectual Property Organization (WIPO) under the Hague Agreement Concerning the International Registration of Industrial Designs (also known as published international design applications) are not assigned a publication number uniquely identifying the published international registration. When citing an international registration, both the International Registration Number (referenced by INID Code 11 in the publication) and the publication date should be included. See the third item under example 5 of subsection IV below.

Jump to MPEP SourceHague Agreement OverviewBasic Hague Agreement PrinciplesInternational Design Applications
Topic

Reference Identification Requirements

2 rules
StatutoryInformativeAlways
[mpep-707-05-e-a08095865da4acefedd777a5]
Call Number Must Appear on Spine or Title Page
Note:
The call number for a book must be located on the spine if it is thick enough, otherwise it should appear on the back of the title page.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)Reference Identification RequirementsPTO-892 Notice of References CitedCitation of References (MPEP 707.05)
StatutoryInformativeAlways
[mpep-707-05-e-3bcee41e9a7e5967b68594ad]
Article Identification In Periodicals Must Include Author, Title, Volume, Issue, Date, And Pages
Note:
The rule requires that when citing articles from periodicals, sufficient information must be provided to identify the article, including author(s), title of the article, volume number, issue number, date, and pages.

Abstracts, abbreviatures, Alien Property Custodian publications, withdrawn U.S. patents, withdrawn U.S. patent application publications, and other non-patent documents should be cited under the section “Non-Patent Documents” on the form PTO-892). See MPEP § 711.06(a) for citation of abstracts, and abbreviatures. See MPEP § 901.06(c) for citation of Alien Property Custodian publications. In citing a publication, sufficient information should be given to determine the identity and facilitate the location of the publication. For books, the data required by 37 CFR 1.104(d) (MPEP § 707.05) with the specific pages relied on identified together with the Scientific and Technical Information Center (STIC) call number will suffice. The call number appears on the “spine” of the book if the book is thick enough and, in any event, on the back of the title page. Books on interlibrary loan will be marked with the call numbers of the other library, of course. THIS NUMBER SHOULD NOT BE CITED. The same convention should be followed in citing articles from periodicals. The call number should be cited for periodicals owned by the STIC, but not for periodicals borrowed from other libraries. In citing periodicals, information sufficient to identify the article includes the author(s) and title of the article and the title, volume number issue number, date, and pages of the periodical. If the copy relied on is located only in the Technology Center making the action (there may be no call number), the additional information, “Copy in Technology Center — —” should be given.

Jump to MPEP Source · 37 CFR 1.104(d)Reference Identification RequirementsPTO-892 Notice of References CitedCitation of References (MPEP 707.05)
Topic

Specification

1 rules
StatutoryRequiredAlways
[mpep-707-05-e-5a03a2d3a65a40e9b5953bd7]
Specification Must Include Specific Sheet and Page Numbers
Note:
When citing part of a reference, the specific sheet and page numbers must be included along with the total number of sheets and pages.

Where less than the entire disclosure of the reference is relied upon, the sheet and page numbers specifically relied upon and the total number of sheets of drawing and pages of specification must be included (except applicant submitted citations). If the entire disclosure is relied on, the total number of sheets and pages are not required to be included on the PTO-892.

Jump to MPEP SourceSpecificationPatent Application ContentOptional Specification Content
Topic

Optional Specification Content

1 rules
StatutoryRequiredAlways
[mpep-707-05-e-ec8bba9c9e9ef018dd5374d3]
Entire Disclosure Not Requiring Sheet and Page Numbers
Note:
If the entire reference disclosure is relied upon, sheet and page numbers do not need to be included on the PTO-892.

Where less than the entire disclosure of the reference is relied upon, the sheet and page numbers specifically relied upon and the total number of sheets of drawing and pages of specification must be included (except applicant submitted citations). If the entire disclosure is relied on, the total number of sheets and pages are not required to be included on the PTO-892.

Jump to MPEP SourceOptional Specification ContentSpecificationPatent Application Content
Topic

Basic Hague Agreement Principles

1 rules
StatutoryRecommendedAlways
[mpep-707-05-e-153d6c8a882918769d117029]
Citation Requires INID and Publication Date for International Registrations
Note:
When citing an international registration, both the International Registration Number (INID) and the publication date must be included.

International registrations published by the World Intellectual Property Organization (WIPO) under the Hague Agreement Concerning the International Registration of Industrial Designs (also known as published international design applications) are not assigned a publication number uniquely identifying the published international registration. When citing an international registration, both the International Registration Number (referenced by INID Code 11 in the publication) and the publication date should be included. See the third item under example 5 of subsection IV below.

Jump to MPEP SourceBasic Hague Agreement PrinciplesInternational Design ApplicationsHague Agreement Overview
Topic

Sequence Listing Format

1 rules
StatutoryRequiredAlways
[mpep-707-05-e-0007cc8b0a2f8dae61471ce0]
Format for Electronic Document Citations Must Match Paper Documents
Note:
The U.S. Patent and Trademark Office requires that the citation format of electronic documents be similar to paper documents, including additional information such as retrieval date and source.
The U.S. Patent and Trademark Office follows the format recommended by World Intellectual Property Organization (WIPO) Standard ST.14, “Recommendation for the Inclusion of References Cited in Patent Documents.” The format for the citation of an electronic document is as similar as possible to the format used for paper documents of the same type, but with the addition of the following information in the locations indicated, where appropriate:
  • (A) the type of electronic medium provided in square brackets [] after the title of the publication or the designation of the host document, e.g., [online], [CD-ROM], [disk], [magnetic tape]. If desired, the type of publication (e.g., monograph, serial, database, electronic mail, computer program, bulletin board) may also be specified in the type of medium designator;
  • (B) the date when the document was retrieved from the electronic media in square brackets following after the date of publication, e.g., [retrieved on March 4, 1998], [retrieved on 1998-03-04]. The four-digit year must always be given.
  • (C) identification of the source of the document using the words “Retrieved from” and its address where applicable. This item will precede the citation of the relevant passages.
  • (D) reference to the unique Digital Object Identifier (DOI) number, or other unique identification number, if known.
  • (E) if considered necessary, the standard identifier and number assigned to the item, e.g., ISBN 2-7654-0537-9, ISSN 1045-1064. It should be noted that these numbers may differ for the same title in the printed and electronic versions.
  • (F) where multiple renderings of the same document are published (e.g., PDF and HTML), an indication of the format (e.g., paper, PDF) and the location of the cited document.
  • (G) use paragraph numbers, sentence numbers and line numbers (if available) to describe the specific location of the cited material within an electronic document.
  • (H) claim numbers, figure numbers, chemical formula numbers, mathematical formula numbers, table heading numbers, gene sequence numbers, and computer program listing numbers if available.
  • (I) specific headings within the document structure such as Best Mode of Performing the Invention or Industrial Applicability can be indicated if page, paragraph, and line numbers are not available in a cited patent document in electronic format.
  • (J) specific passages of the text can be indicated if the format of the document includes pagination or an equivalent internal referencing system, or by the first and last words of the passage cited.
Jump to MPEP SourceSequence Listing FormatPTAB JurisdictionSequence Listing Content

Citations

Primary topicCitation
Examiner's Action (37 CFR 1.104)
PTO-892 Notice of References Cited
Reference Identification Requirements
37 CFR § 1.104(d)
Examiner's Action (37 CFR 1.104)
PTO-892 Notice of References Cited
Reference Identification Requirements
MPEP § 707.05
Examiner's Action (37 CFR 1.104)
PTO-892 Notice of References Cited
Reference Identification Requirements
MPEP § 711.06(a)
MPEP § 901.04
MPEP § 901.04(a)
MPEP § 901.05(a)
Examiner's Action (37 CFR 1.104)
PTO-892 Notice of References Cited
Reference Identification Requirements
MPEP § 901.06(c)

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