How do I conduct a patent search?

Intellectual property filings are useful in determining whether your invention is “novel” (truly new) and whether you have the freedom to commercialize your invention without infringing on other claims that are already under patent protection. You can search for patent applications and granted patents through the government and intergovernmental agencies listed below.

Canadian Intellectual Property Office (CIPO): CIPO’s Canadian Patent Database provides access to 93 years of patent descriptions and images. Guidelines for searching the database is available under the “Help: Searching for Text” link.

United States Patents and Trademarks Office (USPTO): The USPTO provides a quick introductory webinar, How to Conduct a Preliminary U.S. Patent Search: A step by step strategy.

European Patent Office (EPO): This international patent database contains patents from 90 countries and regions. Espacenet is the EPO’s patent database, which offers free access to information about inventions and technical developments from 1836 to today. A quick video introduction to the database can be found here.

World Intellectual Property Organization (WIPO): The WIPO database includes patent information from countries around the world, and often provides English versions of the filings in part (such as the abstract) or in full.

Seven Step Strategy also provides a useful starting point for the patent search process.


Patent searching tips
The University of Toronto patent searching guide suggests that to be most effective in your search for patents you must determine how your invention works, NOT how you will use your invention.

  • Start by making a list of words that describe your idea (including synonyms)
  • Record class/subclass of any related terms
  • Ask yourself:
    • What does the invention do?
    • What is the end result/anything unique/special/ unexpected?
    • What is it made of/method or material of fabrication?
    • What is it used for? (think verbs, as well as nouns)
  • Keep track of useful and non-useful patents (by patent number) to avoid duplication of efforts

To look up patents granted to or filed by specific companies, conduct an “Assignee” search using the company name. Keep in mind that company names are not always in a standard, uniform format, or the filing may be under the name of the parent, subsidiary or other affiliated entity.

Viewing full-text patent images on the USPTO site requires a TIFF viewer and browsing of documents is limited to one page at a time. Once you’ve identified the relevant patents of interest, use Google Patents to access and download the full document as a PDF.