Welcome to the new version of the Patents Manual. Please note there are changes to the numbering and sequence of the chapters and pages in the manual. You are encouraged to take the time to explore and familiarise yourself with this new structure.

4.2.1.1.1 Structure of the IPC

Date Published

IPC Structure

The whole classification set of the IPC is called a scheme. The IPC employs a hierarchical system using sections, classes, subclasses, groups and subgroups as its organisational units.

The highest level is the section. Each section is divided into classes. Classes are made up of one or more subclasses. Each subclass is broken down into main groups. Each part of this hierarchical structure is identified by classification symbols.


IPC Sections

The IPC contains eight sections (A-H).

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

Hierarchy of Subgroups

The hierarchy among subgroups is determined by the number of dots preceding their titles and not by the numbering of the subgroups.

For example: Consider the following classification subgroups





  • G01N 33/49 is hierarchically inferior to the two-dot group G01N 33/483 and the three-dot group G01N 33/487
  • G01N 33/50 is of the same hierarchical level as G01N 33/483


IPC Symbols and Titles

Each IPC place/entry (section, class, subclass, group) is characterised by a Symbol and a Title.

Symbol = a combination of letters and numbers with the exception of the sections, of which the symbol is a capital letter.

Title = phrase describing the technical content (scope)





For more detailed explanations and examples, see Part II. Layout of Classification Symbols and Part III. Hierachical Structure of the Classification of the Guide to the IPC (pages 4-7).


Amended Reasons

Amended Reason Date Amended

Publish from Draft

Back to top