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Searching a Japanese patent/publication number

Patent/Publication Numbers

A patent/publication number is assigned to every published patent document, e.g., examined, unexamined, patent application, or granted patent. The only difference is the kind code. A patent/publication number, whether for the granted patent or the application, is searched in the Patent/Publication Number (/PN) field.

Patent Number System

The Patent Numbering System table demonstrates the various patent numbering systems and how to search for the respective patent numbers on STN, using the STN format. If you are familiar with the Derwent format, that format may also be used.

Searching for Japanese patents

When searching for a Japanese patent prior to 2000, the Year of the Emperor is included in the patent number. The Year of the Emperor was set to 1 when a new emperor took the throne in 1989. For Japanese patents published prior to 1989, subtract 25 from the Western Year to determine the Year of the Emperor. For Japanese patents published in 1989 or later, subtract 88 from the Western Year to determine the Year of the Emperor.

Prior to 1950, a Japanese patent was assigned a continuous serial number.

Search tips for locating Japanese patents

Be aware of the following search tips when searching for patents using a patent/publication number:

• The Western Year 1989 may be represented by the Year of the Emperor 64 or 01
• In CA and CAplus, when you EXPAND on a Japanese patent published since 1989, precede the digit by 0 (e.g., 01, 02, etc.) for the Year of the Emperor
• In INPADOCDB, when you EXPAND on a Japanese patent published since 1989, use only the number (e.g., 1, 2, etc.) for the Year of the Emperor
• For some Japanese patents, the PN for an A kind code has the same value as a different patent's B kind code

Patent Numbering System	STN Format	Format Description
Countries that use a continuous numbering system (ex: USA granted patents, EP, AU)	CCNNNN/PN	CC - ISO country code NNNN - 1-8 digit number without spaces or punctuation (this is a variable length number)
Countries that restart the numbering each year (Ex: JP starting in 2000, WO, BR, USA patent applications)	CCYYYYNNNNNN/PN or CCYYYY-NNN/PN (The system will replace the "-" with the correct number of zeros.)	CC - ISO country code YYYY - the publication year NNNNNN - 6-digit number without spaces or punctuation (if necessary, add leading zeros to make it a total of 6 digits or add a dash)
Japan, prior to 2000, which restarted published application numbering each year	JPEENNNNNN/PN	JP - ISO country code for Japan EE - last 2 digits of the Japanese Emperor year NNNNNN - 6-digit number without spaces or punctuation (if necessary, add leading zeros to make it a total of 6 digits)
Calculating the Year of the Emperor
Emperor	Year of the Emperor	Western Year
Hirohito	25-64	1950-1989
Akihito	01-12	1989-2000