This is a short article to help beginner's who are new to patent class codes learn to use them effectively in Amplified.

What are class codes and why use them?

Every patent has a set of tags indicating the technology fields covered by the invention. These are called classification codes or class codes. Using patent classification codes to filter results is a powerful way to see only results about very specific technical aspects.

There are multiple classification systems but the most common and widely applied are the Cooperative Patent Classification System (CPC) and International Patent Classification System (IPC). These class codes are organized hierarchically starting from broad high-level codes called Sections that are followed by class, subclass, and group codes which are increasingly specific. In this article, we'll focus on CPC codes.

Understanding CPC codes

At the highest level, CPC codes are organized into 9 broad areas. We've included the codes and definitions below for your reference.

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
Y: GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS

Amplified already understands technology well enough that you won't need to use these high level codes in your searching. However, deeper level codes are extremely specific which, when used as a filter, can be a powerful complement to your Amplified results. For example, the CPC code C07D 203/00 is defined as Heterocyclic compounds containing three-membered rings with one nitrogen atom as the only ring hetero atom. Whoa, that's a lot of detail. Here's how that code is organized in the CPC hierarchy:

Browsing definitions and searching for class codes

Thanks to a variety of free online resources, it is easy to search for a class code and see it's definition. The European Patent Office provides a free online service called Espacenet where you can quickly browse class codes or search using specific keywords as shown below.

Espacenet Cooperative Patent Classification Service: https://worldwide.espacenet.com/classification

Let's try searching for a relevant CPC codes together

Imagine you were looking for information about a smart toaster and decided to explore those that do not require a wifi connection and instead utilize short-range communications only. You can do this by adding a class filter, for example H04W4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication.

Finding this code is easy. You can quickly find this code by navigating to the Espacenet CPC service and typing in a keyword, for example, bluetooth or clicking through the codes to browse them.

H04W 4/00 is about wireless networks but if you click on that code you'll see a list of even more detailed codes.

If you scroll down through this list you'll find H04W 4/80 which is specifically related to short range communication such as NFC and RFID.

Using a specific class code like this as a filter on top of your existing Amplified results is a fast and powerful way to quickly locate relevant results or quickly explore a technology field from different angles.

A word of warning

Classification codes are created by people and assigned by people. With over 260,000 codes and millions of new patents every year this is a monumental task and despite best efforts there will always be subjectivity in how they are used as well as human error. So, while you can do a lot with class codes they are not guaranteed to include every patent that fits the definition. So, after using class code filters, it is always a good idea to remove your filters and turn on learning so you can capture relevant results not covered by the class codes.

Congratulations, this should be enough information for you to use class codes effectively in Amplified!

For curious minds, the EPO and USPTO have jointly prepared free and publicly available documentation and training on classification codes.

CPC Training: https://www.cooperativepatentclassification.org/Training

Official definitions and detailed information about IPC codes: https://www.wipo.int/classifications/ipc/en/faq/

Search and browse IPC codes: https://www.wipo.int/classifications/ipc/ipcpub/

Official definitions and detailed information about CPC codes: https://www.cooperativepatentclassification.org/obj

Search and browse CPC codes: https://worldwide.espacenet.com/classification

Did this answer your question?