International Patent Classification (IPC)

The International Patent Classification system (IPC), established by the Strasbourg Agreement 1971, is a hierarchical system which uses language-independent symbols to classify patents and utility models according to the area of technology to which they relate.

The technical content of almost all the patent documents published worldwide is classified using this system.

The publishing office assigns an IPC symbol or symbols which are valid at the time of publication of the application.

You can find the text of the IPC and related documentation (e.g. IPC Guide (2012) ) on the IPC page of the World Intellectual Property Organization (WIPO) website.

IPC classification symbols are made up of a letter denoting the IPC section (e.g. A), followed by a number (two digits) denoting the IPC class (e.g. A63), then a letter denoting the IPC subclass (e.g. A63B). A number (variable, 1-4 digits) denotes the IPC main group (e.g. A63B49). This is followed by a forward slash "/" and a number (variable, 2-6 digits) denoting the IPC subgroup (e.g. A63B49/02).

Note: IPC symbols printed with a blank after the fourth letter or digit must be entered in the search field in Espacenet without any blanks.

You do not need to use wildcards, as the data is "auto-truncated", meaning that each symbol is indexed at different levels. All you need to enter, for example, is either B65 (class level), B65D (subclass level), B65D81 (main group level) or B65D81/32 (subgroup level).

In other words, A63B49 will search for all the symbols under main group A63B49/00 (including the main group itself).

You can enter up to ten symbols. The default operator is AND.

You can also refine your search using search modifiers:

• ai: selects IPC, invention information
• an: selects IPC, additional information

Example: an:G11B5/84

Invention information is information in patent documents which describes or presents the technical innovations made known in the publication and which adds to the prior art.

Additional information is non-trivial technical information which does not in itself represent an addition to the state of the art but might constitute useful information for the searcher.

Search modifiers should be entered in lower-case letters.

The IPC symbols are displayed according to the following priorities:

• Classification symbols allocated by offices using the full IPC come before classification symbols allocated by offices classifying in main groups only
• Invention information comes before additional information
• Current IPC symbols come before old IPC symbols (versions 1-7)
• Old IPC symbols (versions 1-7) are displayed in normal font and prefixed with the label "(IPC1-7)"

The IPC symbols in the result list (and in the documents) are displayed as follows:

• IPC symbols allocated by offices classifying in the full IPC: in italics
• IPC symbols allocated by offices classifying in main groups only: non-italics
• Invention information symbols: bold
• Additional information symbols: non-bold

You can search the IPC without using search modifiers.