Exhibitions & conferences [3/2001]

Japanese FI classification and F-terms now available in English

A feature of Japanese patent documentation is the FI and F-term classification system developed by the Japanese Patent Office (JPO). Since April 2001, it has been possible to search Japanese patent literature using FI classification and F-terms in English.

FI (File Index) classification

FI or "File Index" is the internal classification system used by the Japanese Patent Office to classify the technical content of patent documents and to organise prior-art searches more efficiently.

FI classifications are made up of an International Patent Classification (IPC) sub-group, followed by an IPC subdivision symbol in the form of a three-digit number. These IPC subdivision symbols are unique to FI classes and are structured hierarchically. Optionally, a file discrimination symbol in the form of a letter can be added.

Example of FI subdivisions for G06F9/00Example of FI subdivisions for G06F9/00

With its various subdivisions, the File Index (FI) classification has about 170 000 classes, whereas the IPC has some 70 000 only.


This classification is applied to patent documents in parallel to the IPC and FI classifications.

While the IPC classifies documents mostly from a single technical viewpoint, the F-term classification works from multiple viewpoints. In effect, the technical content of patent documents is analysed by JPO examiners and divided into different themes, each theme being given a special "theme code". Themes are further split into terms ("term codes"). Term codes are assigned according to various technical viewpoints (eg material, operation, product, purpose, etc.).

Example of F-term: 2B003 AA 01

2B003 Theme code (representing a technological field)
AA Viewpoint (material, operation, purpose, etc.)
01 Figure (subdividing the viewpoint)

Thus, every F-term consists of a five-digit theme code and four-digit terms, for example 2B003AA01. In our example, 2B003 is the theme code ("artificial fish reefs"), corresponding to FI classes A01K61/00,311 - 61/00,321. AA01 is the term, in this case "sunken installation configurations".

There are currently about 1 700 different theme codes with a total of some 350 000 terms.

Searching with FI classification and F-terms

In spring 2001, FI and F-terms were made available to the public in English, with search facilities, as part of the JPO's IPDL service (www.ipdl.jpo.go.jp/homepg_e.ipdl).

Patent Map Guidance

Users who are not familiar with the FI or F-term classifications should start their searches by consulting the Patent Map Guidance service. This service offers an overview of the main FI sections, with the option of displaying the corresponding lower hierarchy levels, complete with descriptions in English. For F-terms it is possible to display groups of theme codes, descriptions of the various theme codes, and the complete F-term lists in English. A searchable concordance list allows users to determine the corresponding F-term theme codes for FI classes and vice versa.

FI/F-term search

This newly established search facility allows users to search the complete spectrum of Japanese patent and utility model publications. Coverage for patents goes back to 1914, and utility models are covered back to 1912.

For more information on FI classification and F-terms or any other aspect of Japanese patent information, please contact Irene Schellner or Andrea Pfau:
Tel.: +43 1 52126 4372
Fax: +43 1 52126 4197
e-mail: jpinfo@epo.org


[free subscription to paper issue] [back to news] [home page] [contact]