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Patents: Finding patents

Finding US patents

The U.S. Patent & Trademark Office (USPTO) Patent Database includes full text of patents from 1790 - present and also provides TIFF images of most of them.

By Patent Number

  1. Go to USPTO Database.
  2. Select Patent Number Search or Publication Number Search.

By Subject

  1. Go to USPTO Database and select Quick Search. Enter keywords in the search box.
  2. Find a patent that is close to what you're looking for.
  3. Note the Cooperative Patent Classification (CPC) number/Subclass for that patent, e.g. A01D 711/111 .
  4. Do a search of that Class/Subclass in USPTO Database to find more patents on that subject.

OR ...

  1. Go to CPC Classification System Scheme and search for common terms or keywords.
  2. Use the Class/Subclass numbers you found to check the CPC Classification System Scheme to see if they are on target.
  3. Search by Class/Subclass numbers in USPTO Database.

 You can use the same method of searching in other patent databases on the web.  See the Patent Websites tab in this guide for more databases.

 

See this excellent tutorial from the US Patent and Trademark Office on the patent search process.

This is a helpful guide from the USPTO which uses their 7 Step Strategy with new CPC code system.

Finding international patents

The European Patent Office maintains a free database of worldwide patents (including U.S. patents) called Espacenet. Images of patents are provided in PDF format, but can only be printed one page at a time.

By Patent Number

  1. Go to Espacenet and enter the patent number (with or without the country code) in the Smart Search box.
  2. All documents with that number will be listed. 
  3. Choose the patent record you are looking for.

By Subject

  1. Go to Espacenet Advanced Search page and enter your keywords in the "Title or abstract" box.
  2. Find a patent that's close to what you're looking for.
  3. Note the International Classification number/Subclass for that patent, e.g. H04B1/59.
  4. Do a search of that Class/Subclass in the serch box at the Espacenet Classification Search page to find more patents on that subject.

 

Espacenet Tutorial - How to search esp@cenet, the European Patent Office's online patent database

 

See the Patent Websites tab for additional international patent databases.

 

Finding chemical patents

Chemical Abstracts Service (CAS) indexes chemical patents from approximately 25 countries and patent organizations. UC San Diego affiliates may search the online CAS database, SciFinder. It does require a one-time registration (links below).

You can find patents by search on references or reactions, then browsing the results or filtering to see only patents. Along with linking out to patents, you can also use the PatentPak viewer to view the patents with the chemistry content highlighted.

Tutorials on Finding Patents