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Patent Filing & Litigation

FAQ: What Do I Need to Know About Patent Classification?

Before you can begin working towards a patent for your idea, you will need to conduct a patent search to ensure that your idea is original. But before you can start this process, you will need to understand how the patent classification system works. Accurate search results will guide you throughout the patent lifecycle, so it’s crucial to know what you’re looking for and how to conduct your search properly.

How are patents classified?

Patents are classified by the technology or type of technical features employed in the invention described. Once the technology is designated, the concept or product will receive a code and be grouped with other related patents. Classification codes follow a layout scheme including section, class, subclass, group, and subgroup. The Cooperative Patent Classification system and the Internation Patent Classification system are the most commonly used.

What is Cooperative Patent Classification?

The Cooperative Patent Classification (CPC) is a partnership between the United States Patent Classification (USPC) and the European Classification (ECLA) systems established in 2013. The USPC and ECLA worked in coordination to combine the best practices from each system into a singular, strategic entity. It classifies technologies into about 200,000 subgroups. CPC remains in compliance with the International Patent Classification and is overseen by both the US Patent and Trademark Office and the European Patent Office.

How do you determine Cooperative Patent Classification?

The CPC is divided into nine main sections that are then further branched by class, subclass, group, and subgroup. The main sections are as follows:

A: Human Necessities
B: Performing Operations; Transporting
C: Chemistry; Metallurgy
D: Textiles; Paper
E: Fixed Construction
F: Mechanical Engineering; Lighting; Heating; Weapons; Blasting Engines or Pumps
H: Electricity
Y: General Tagging of New Technological Developments; General Tagging of Cross-over technologies spanning over several sections of the IPC; technical subjects covered by former USPC cross-reference art collections and digest

The CPC provides a full scheme and definition table that identifies each classification code. Updates to the code classification should also be considered prior to a search. To check for updates, visit the CPC website.

What is International Patent Classification?

Like the CPC, the International Patent Classification (IPC) provides a hierarchy to classify patents by technology and technical field. It is used for the selective dissemination of information and searching through prior patent art. Rather than classifying 200,000 subgroups like CPC, IPC only classifies patents and patent applications into 70,000 subgroups.

How do you determine International Patent Classification?

IPC uses a very similar system to CPC. This system uses the same A-H sections as CPC, but it lacks the ninth Y section for general tagging and new developments. Like CPC, IPC also has its own scheme and definitions available online.

How To Search Patents by Classification

Better, faster decision-making starts with’s InnovationQ+. We allow users to search and filter through CPC codes, patent numbers, conceptual statements, and invention disclosure excepts in one tool. Using a proprietary semantic AI engine to aggregate billions of global IP data points, you can search through patent and non-patent literature and get expert-level results more efficiently than other traditional alternatives. Our system also incorporates a five-star rating indicator, allowing you to gauge what results are most relevant to your search concept.