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1851 Identification of Patent Documents [R-07.2015]

The examiner, in completing the international search report as well as the written opinion and international preliminary examination report, is required to cite the references in accordance with the provisions of Administrative Instructions Sections 503 and 611 and WIPO Standard ST.14. These sections of the Administrative Instructions require reference citations to include, in addition to other information which is apparent from the forms which the examiner fills out, an indication of the two-letter country code of the country or entity issuing or publishing the document and the standard code for identifying the kind of patent document. The discussion which follows is limited to the identification of patent documents (and nonpatent publications) and a listing of the two-letter country codes for countries or other entities which issue or publish industrial property information.

The standard codes for identifying different kinds of patent documents are found in the “WIPO Handbook on Industrial Property Information and Documentation” - WIPO Standard ST.16 which is published by the World Intellectual Property Organization. The listing is extensive. The Quality Assurance Specialists in each Technology Center (TC) have a complete copy of Standard ST.16. It is also accessible on WIPO’s website ( Provided herein is an abbreviated version representing the countries and codes commonly used by the examiner in preparing search reports.

U.S. patents published before January 2, 2001, are Code A documents generally. Beginning with patents published on January 2, 2001, U.S. patents are Code B documents. Patent Application Publications, first published on March 15, 2001, are Code A documents. Reexamination certificates published before January 2, 2001, are Code B documents. Reexamination certificates published on or after January 2, 2001, are Code C documents. Tables providing a complete list of the kind codes of patents and other documents published by the USPTO are included in MPEP §  901.04(a). All nonpatent literature documents are Code N. Numerical designations are sometimes found on published documents along with the letter code designation. These should be used by the examiner only if such numerical designation is on the document. Numerical codes along with letter codes can be found, for example, on certain published patent documents such as the German Offenlegungsschrift and published international applications. If numerical designations are not provided, the examiner should use only the letter code designation.

The most commonly cited documents are patents and published patent applications. A guideline for the citation of such documents is listed below. The listing is indicated in the order in which the elements should be listed.

In the case of a patent or published patent application:

  • (A) The Office that issued the document, by the two letter code (WIPO Standard ST.3);
  • (B) The number of the document as given to it by the Office that issued it (for Japanese patent documents the indication of the year of the reign of the Emperor must precede the serial number of the patent document);
  • (C) The kind of document, by the appropriate symbols as indicated on the document under WIPO Standard ST.16 or, if not indicated on that document, as provided in that Standard, if possible;
  • (D) The name of the patentee or applicant (in capital letters, where appropriate, abbreviated);
  • (E) The date of publication of the cited patent document or, in case of a corrected patent document, the date of issuance of the corrected patent document as referred to under INID code (48) of WIPO Standard ST.9 and, if provided on the document, the supplementary correction code as referred to under INID code (15);
  • (F) Where applicable, the pages, columns, lines or paragraph numbers where the relevant passages appear, or the relevant figures of the drawings.

The following examples illustrate the citation of a patent document as indicated above:

JP 10-105775 A (NCR INTERNATIONAL INC.) 24 April 1998 (24.04.1998) paragraphs 26 to 30.

DE 3744403 A1 (JOSEK, A.) 29 August 1991 (29-08-1991), page 1, abstract.

US 5,635,683 A (MCDERMOTT, R. M. et al.) 03 June 1997 (03/06/1997), column 7, lines 21 to 40.


The Code, WIPO Standard ST.16 is subdivided into mutually exclusive groups of letters. The groups characterize patent documents, nonpatent literature documents (N), and restricted documents (X). Groups 1-7 comprise letters enabling identification of documents pertaining to different publication levels.

Part 7.3 "Examples and Kinds of Patent Documents" provides, in the first document (Part 7.3.1), examples of patent documents, previously and currently published, or intended to be published, listed according to code. The second document (Part 7.3.2) contains a listing, in alphabetical order of issuing industrial property office, of kinds of patent documents and their codes, as applied by the offices. Finally, the third document (Part 7.3.3) provides access to a collection of samples of first pages of patent documents published by industrial property offices.

Country Codes

The two-letter country codes are set forth in WIPO Standard ST.3, which is published in the “WIPO Handbook on Industrial Property Information and Documentation” and is accessible via the Internet at the WIPO website ( en/part_03_standards.html). WIPO Standard ST.3 provides, in Annex A, Section 1, a listing of two-letter country codes and/or organizational codes in alphabetic sequence of their short names for the states, other entities and intergovernmental organizations issuing or publishing industrial property documents. Codes for states or organizations that existed on January 1, 1978, but that no longer exist are provided in Annex B, Section 2. Annex B, Section 1 lists States for which the Codes have changed.



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Last Modified: 02/16/2023 12:58:18