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Patents and Designs

How to Find a Patent Document Using a Patent Number

The easiest way to retrieve a patent document from a patent database is by its publication or patent number. Patent documents can be identified by one or more numbers, including:

  • Provisional application number: the number assigned to a U.S. provisional application when it is filed;
  • Application number: the number assigned to the patent application when it is filed;
  • Publication number: the number assigned when the patent application is published at 18 months after filing; and
  • Patent number: the number assigned when the application becomes a patent.

The patent number usually appears in the top right-hand corner of the front page of a patent document.

Number Formats

Patent document numbers consist of three parts: a country code that identifies the country of origin, a document number and a kind code that identifies the type of document. Common country codes include CA (Canada), DE (Germany), EP (European Patent Office), JP (Japan) and US (United States). Kind codes include A (published application), B (US patent) and C (CA patent).

Patent Number Format


Search Tips


  • Look for a patent number on the product or packaging. Many companies print patent document numbers on their products as public notification of their patent rights. Use the patent number to search and retrieve a copy of the patent from a patent database.
  • Do include the country code but not the kind code
  • Identify the company that makes (or made) the product. Look for company names on both the product and its packaging. Remember that the company that distributes a product may be different from its manufacturer.