Month: January 2022

The US Patent Classification (USPC) System

In order for searches of the existing patent database to be conducted in a reasonable manner the entire collection of patents is organized into a classification system, known as the Manual of Patent Classification. Utility patents are divided into 460 numbered classes identified by a 3-digit number and title. Some examples are:

  • 084 Music
  • 257 Active solid-state devices (e.g., transistors, solid-state diodes)
  • 709 Electrical computers and digital processing systems: multicomputer data transferring

Each class is divided into sub-classes arranged in a hierarchical manner and known as the “class schedule” as you can see from how to file a patent with InventHelp article.

Part of the Class 257 schedule is shown below:

1. Bulk effect device
2. Bulk effect switching in amorphous material
3. With means of localizing region of conduction (e.g., “pore” structure)
4. With specified electrode composition or configuration
5. In array
6. Intervalley transfer (e.g., “Gunn” effect)
7. In monolithic integrated circuit
8. Three or more terminal device

A classification consists of Class/Subclass, so a bulk effect semiconductor device, for example, employing the Gunn effect would have a classification of 257/6. One or more classifications are assigned to a patent or patent application based primarily upon the disclosure of the subject matter in the Claims.

Taken as a whole, there are more than 154,000 class/subclass combinations in the USPC! This means that a person performing an exhaustive search of the USPC must have an expert understanding of both the subject matter and the USPC itself. Read more about patenting process on patent my invention through InventHelp.