Patents and Trademarks

How do I search for patent information?

Government agencies or patent offices tend to have the most authoritative information on patents in a particular country. They're a good place to look when you need to verify information or are doing research that has legal implications.

U.S. Patent & Trademark Office (USPTO) 

• The USPTO is the federal agency for granting U.S. patents and registering trademarks. They have separate databases for patent applications (AppFT) and awarded patents (PatFT).

Google Patents

• Google has made nearly all US and European patent documents available in searchable full-text. While it's a great tool for beginners, it has some limitations for the more experienced patent searcher.
• Google Patent Searching Guide

CIPO's Canadian Patent Database

• CIPO lets you access 153 years of patent descriptions and images. You can search, retrieve and study more than 2,470,000 patent documents.

European Patent Office (EPO)

• Espacenet offers free access to more than 130 million patent documents worldwide, containing information about inventions and technical developments from 1836 to today. Includes PDFs of US patents filed in other countries.
• http://www.epo.org/searching/free/espacenet.html (available in German, English, or French)

China Patent Office Database (SIPO)

• Click the "English" link at the top of the page to search in English.

Japan Patent Office (JPO)

• Click the "English" link at the top of the page to search in English.

World Intellectual Property Organization (WIPO)

• WIPO is an agency of the United Nations. Its database allows searching for patents worldwide.

You can also search for patents by their classification. These resources can help you do that:

• Index to the United States Patent Classification (USPC) System

  Classes arranged alphabetically. Links are provided to each numerical class, which is presented as an expandable tree. Links may include definitions, which are extremely useful in understanding the rationale for a classification assignment.

• Cooperative Patent Classification (CPC)

  Partnership between the USPTO and the EPO to harmonize their existing classification systems and move towards a common classification scheme. The initial release was in 2012. As of 2013, the CPC replaces the ECLA, the classification scheme used by the European Patent Office.

• European Classification System (ECLA)

  Used by the European Patent Office (EPO) examiners for their patent application searches, ECLA was a more detailed version of the IPC. As of 2013, it was replaced by the Cooperative Patent Classification (CPC) scheme, which the USPTO also adopted.

• International Patent Classification (IPC) Portal

  Search engine and background documentation for the IPC.