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Patent Information

Resources selected to assist students and researchers in the areas related to patents and patent information

What is a patent classification system?

A patent classification system breaks down patentable technology into manageable units. Since the total number of patents is so large, classification search is useful to find all patent publications in a particular technical area.

The International Patent Classification (IPC) is currently used by over 70 patent authorities to classify and index the subject matter of published patent specifications. The IPC is maintained and is administered by the World Intellectual Property Organisation (WIPO), based in Geneva. IPC combines letters and numbers to categorize very precisely the technology described in a patent document. It divides patentable technology into 8 key areas:

A: Human Necessities
B: Performing Operations, Transporting
C: Chemistry, Metallurgy
D: Textiles, Paper
E: Fixed Constructions
F: Mechanical Engineering, Lighting, Heating, Weapons, Blasting
G: Physics
H: Electricity

Within these areas technology is divided and subdivided to a detailed level, which allows the subject matter of a patent specification to be very thoroughly classified. Every patent document published has at least one IPC symbol printed on the front page.

International Patent Classification Current version

Other Schemes: Cooperative Patent Classification | U.S. Patent Classification | European Classification (ECLA)

Patent application

FAQ on Patent Applications at CityU

How to apply for a patent in:

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