International Patent Classification (IPC)

The International Patent Classification (IPC) is a globally standardized system for categorizing patent documents based on their technical subject matter. Developed and maintained by the World Intellectual Property Organization (WIPO), the IPC is a foundational tool for prior art searches, patentability assessments, freedom-to-operate (FTO) analyses, and patent landscape studies.

Rather than relying solely on keywords which can vary by language, drafting style, or terminology the IPC enables searchers to locate all relevant patent documents within a technical field, regardless of how the invention is described.

The IPC consists of eight main sections, covering all fields of technology and comprising approximately 70,000 subclasses and groups.

How IPC Is Used in Practical Patent Searching

In professional patent searching, IPC codes are rarely used alone. Instead, they are combined with keywords to:

Narrow results to a specific technical field
Reduce irrelevant documents
Increase confidence that critical prior art has not been missed

A typical professional search query combines:

IPC classification → defines the technical domain
Keywords → capture the specific problem, function, or application

Example query structure (PATENTSCOPE syntax):


IC:(G01N) AND EN_ALLTXT:(TITRATION)

This query retrieves documents classified under chemical analysis (G01N) that also mention titration anywhere in the English text.

How WOIPS Identifies IPC and CPC?

WOIPS Feature

The WOIPS platform automatically analyzes your innovation's information using a trained artificial intelligence system and identifies the most relevant international patent classifications (IPC/CPC). It then uses these classifications to search for patent prior art search.

Section A:

Human Necessities

This section covers inventions related to daily human needs and lifestyle applications.

Examples:

Agricultural machinery and irrigation systems
Food processing methods and packaging technologies
Medical devices, diagnostic tools, and pharmaceuticals
Personal care products and fitness equipment

Typical IPC areas: A01 (Agriculture), A23 (Foods), A61 (Medical or Veterinary Science)


IC:(A61B) AND EN_ALLTXT:(DIAGNOSTIC)

Section B:

Performing Operations; Transport

This section includes industrial processes and transportation-related technologies.

Examples:

Manufacturing and assembly methods
Packaging, labeling, and material handling systems
Vehicles, logistics systems, and shipping technologies

Typical IPC areas: B01 (Physical or Chemical Processes), B60 (Vehicles), B65 (Conveying; Packaging)


IC:(B65D) AND EN_ALLTXT:(PACKAGING)

Section C:

Chemistry; Metallurgy

Section C focuses on chemical compositions, reactions, and material processing.

Examples:

Chemical compounds and formulations
Battery materials and electrolytes
Metal alloys and metallurgical processes

Typical IPC areas: C01–C14 (Chemistry), C21–C23 (Metallurgy)


IC:(C08G) AND EN_ALLTXT:(POLYMER)

Section D:

Textiles; Paper

This section relates to fiber materials, fabrics, and paper production.

Examples:

Textile manufacturing processes
Nonwoven fabrics and smart textiles
Paper processing and packaging materials

Typical IPC areas: D01 (Fibres), D03 (Weaving), D21 (Paper-making)


IC:(D01F) AND EN_ALLTXT:(SYNTHETIC FIBER)

Section E:

Fixed Constructions

Section E covers construction-related technologies and civil engineering solutions.

Examples:

Building structures and materials
Road, bridge, and tunnel construction methods
Smart building systems and modular construction

Typical IPC areas: E01 (Roads), E04 (Building), E05 (Locks, Keys)


IC:(E04B) AND EN_ALLTXT:(INSULATION)

Section F:

Mechanical Engineering; Lighting; Heating; Weapons; Blasting

This section includes mechanical systems and energy-related technologies.

Examples:

Engines, turbines, and power transmission systems
Heating, ventilation, and air-conditioning (HVAC) systems
Industrial lighting systems and safety mechanisms

Typical IPC areas: F01–F04 (Engines), F21 (Lighting), F24 (Heating)


IC:(F24F) AND EN_ALLTXT:(VENTILATION)

Section G:

Physics

Section G covers measurement, control systems, optics, and data processing technologies.

Examples:

Sensors, measuring instruments, and test equipment
Optical systems, imaging devices, and lasers
Control systems and signal processing methods

Typical IPC areas: G01 (Measuring), G02 (Optics), G05 (Control)


IC:(G01N) AND EN_ALLTXT:(SENSOR)

Section H:

Electricity

This section is highly relevant for software-related inventions, AI, and digital technologies.

Examples:

Artificial intelligence and machine learning systems
Computer architecture and data processing methods
Telecommunications, networks, and cybersecurity solutions

Typical IPC areas: H04 (Communications), H03 (Electronic Circuits), H01 (Basic Electrical Elements)


IC:(H04L) AND EN_ALLTXT:(ENCRYPTION)

Why IPC Is Essential for Prior Art and Patent Searches

Using IPC codes in patent searches allows inventors, patent professionals, and researchers to:

Identify all relevant prior art within a technical field
Overcome language barriers in global patent databases
Perform structured and repeatable patent searches
Improve accuracy in novelty and inventive step assessments

Each IPC code follows a hierarchical structure:

Section
Class
Subclass
Main Group
Subgroup

This hierarchy enables both broad exploratory searches and highly focused technical analyses, making IPC-based searching a cornerstone of professional patent research.

Practical Tip for Effective Searches

A best practice is to:

Start with broader IPC subclasses
Combine them with core technical keywords
Gradually refine the query using narrower IPC groups and additional keywords

This approach mirrors how professional patent examiners and patent attorneys conduct high-quality prior art searches. Read more about patent prior art search.

For official and detailed IPC definitions, users should consult the WIPO IPC classification resources.