F-term (patent law)
- This article is about the patent classification used in Japan. For F-term in theoretical physics, see F-term.
In Japanese patent law, F-term is a system for classifying Japanese patent documents according to the technical features of the inventions described in them. It complements the International Patent Classification (IPC) system by providing a means for searching documents from a different viewpoint than that provided by the IPC system.
The F-term system was developed in 1987 by the Japan Patent Office (JPO) and it is maintained by the same body. A symbol attached to a patent document, indicating that the invention disclosed in the document has a particular technical feature, is also called F-term.
The F-term classification system consists of themes and terms.
The coverage area of the IPC is divided into approximately 2900 categories, each of which is called a theme, and each theme spans a range of IPC subgroups. A theme identified by the title describing the range or the theme-code which consists of five digits allocated uniquely to each theme; for example, a theme spanning IPC range A01K 87/00--87/06 is identified by its title "Fishing rods" and its theme-code "2B019".
Each theme has a number of viewpoints and each document is classified repeatedly for each viewpoint in the respective theme. For example, Theme 2B019 "Fishing rods" has the following twelve viewpoints: structures, raw materials, surface processing and patterns, illumination, accessory implements, protective covers, plugs, fishing line guides, top guides, mounting cylinders, plate configurations and pipe elements.
From each viewpoint, documents are classified into several groups and labeled with a four-digit code called the "term" or "F-term". For example, from viewpoint "structures", all fishing rod documents are classified into fourteen groups such as AA01 "Cross-sectional configurations", AA03 "Built-in reels at the bottom of the rod", etc.; from viewpoint "raw materials", all fishing rod documents are classified into 23 groups such as AB01 "Rods of fiber-reinforced plastic (FRP)", AB41 "Natural materials combined with fiber-reinforced plastic (FRP)", etc.
All terms concerning a theme are put into a tabular form called an "F-term list", which are available online, e.g., 2B019. (Some descriptions of F-terms may seem strange because of incorrect translation from the original Japanese)
 | This article may require copy editing for grammar, style, cohesion, tone, or spelling. |
A fictional example
The F-term system will be best understood through a fictional example, since a practically-used example inevitably involves technical knowledge in a particular field. Let us assume we are to search a fictional cooking recipe database.
The IPC-style classification of recipes may be as follows:
X99Y 1/00 Dishes X99Y 1/02 . Meat dishes X99Y 1/04 . . comprising beef X99Y 1/06 . . comprising pork X99Y 1/08 . . comprising lamb X99Y 1/10 . comprising seafood X99Y 1/12 . comprising vegetables
This classification of recipes is based on a single viewpoint, the main ingredient of dishes. Hence we can browse all recipes of meat dishes by selecting recipes labeled "X99Y 1/02", "X99Y 1/04", or "X99Y 1/06"; we can browse all recipes of beef dishes by selecting recipes labeled "X99Y 1/04"; etc.
However, how can we browse all Chinese recipes? How can we pick up halaal lamb recipes without browsing all recipes? These problems are common when we use the IPC because the IPC is based on a single viewpoint. The problems can be solved using the F-term. The F-term-style classification of recipes may be as follows:
9Z999 Dishes (X99Y 1/00--1/12) AA INGREDIENTS AA11 Meat AA12 . Beef AA13 . Pork AA14 . Lamb AA21 Seafood AA22 . Fish AA31 Vegetable BB CUISINE BB41 Asian BB42 . Chinese BB43 . . Cantonese BB44 . Turkey BB51 European BB52 . French BB53 . Italian CC COOKING CC11 Boiled CC21 Fried CC31 Roasted CC41 Steamed DD SPECIAL DD11 Haraal DD12 Vegetalian
"9Z999" identifies each F-term sheet called theme. "X99Y 1/00--1/12" in the parentheses indicates this sheet is applicable to documents having the IPC range of X99Y 1/00--1/12. "AA", "BB", or "CC" identifies each viewpoint. "AA11", "AA12", etc. identifies each feature viewed from the specified viewpoint and it is called a term or a F-term.
We can pick up all Chinese recipes by selecting recipes having "BB42" on the front page. Similarly, we can pick up halaal lamb recipes by selecting recipes having both "AA14" and "DD11". This procedure can be done most efficiently using computers.
External links
- F-term lists by Japanese governmental agency