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Finding patent information: Classification

Patent classification systems

Patent classification systems work in the same way as the library's shelfmark system:  they assign a number to a subject.  This can be very helpful when searching patent databases: there can be many different words to describe the same topic.  If you can find a number for your topic you don't have to search for all the possible words, you can use the number instead.

International Patent Classification (IPC)

IPC is managed by the World Intellectual Property Organisation (WIPO). The main categories are:

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

It is a hierarchical system and you can drill down to a very specific subject. For example:

G                 Physics
G02              Optics
G02C           Spectacles, sunglasses or goggles ...
G02C5          Construction of non-optical parts
G02C5/14     . Side members
G02C5/20     .. Adjustable, telescopic

Co-operative Patent Classification System (CPC)

The Cooperative Patent Classification (CPC) is based on the IPC but gives a more specific level of detail.  It is jointly managed by the EPO and the US Patent and Trademark Office.  Sections A-H are organised in the same way but there is an additional section:

Y - General tagging of new technological developments; etc.

UK patent application GB2340173A

The patent we are looking at, GB2340173A, has two International Patent Classification codes:

A63B 29/00 - Apparatus for mountaineering 

F16B 45/02 - Hooks with pivoting closing member

You could use these codes to search for similar inventions, without having to use keywords.