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Find patents

You have an idea for an invention, or have gone so far as to create a prototype. Before marketing your invention, you will need to determine if your invention has already been patented. Start by conducting a thorough patent search.

What is a patent?

A patent is a right of ownership granted to a person by the government to exclude others from making or selling the claimed invention for a period of twenty years.

There are three main types of patents:

  • Utility – granted for the function of something that is mechanical, electrical, chemical, compositional, or any combination of these
  • Design – granted solely on the look or appearance of something
  • Plant – granted for unique, asexually reproduced plants

See general information concerning patents (including how to file an application).

Search for patents

You may need to search a number of different patent sites, so it is useful to keep a log of all your search activity.

To begin your search:

  1. Brainstorm keywords to describe your invention. Be sure to think of synonyms.
  2. Search Google Patents using your keywords. The advanced search lets you enter phrases or exclude a word.
  3. Write down the class and subclass of the similar invention.
  4. Use the class and subclass to search patents and patent applications at the U.S. Patent and Trademark Office's patent classification search.
  5. Trace related patents through references.

See also: 7-step U.S. patent search strategy (U.S. Patent and Trademark Office).