Patent Information

How to Search By Patent Number

Need to locate a patent by its patent number?

Do you have a U.S. patent number in hand and want to find a copy of the full patent?

Here are 4 quick ways to search by patent number, and then obtain the full text of the patent.

1. Go to the USPTO Number Search Site and enter your number in the search box.
(Example: 5,976,023 )

2. Go to the PAT2PDF site and enter your number in the search box. This site gives you a PDF version of the patent to download for free.
(Example: 5,976,023 or 5976023)

3. Go to the advanced patent search page of Google Patent Search and enter your number in the "Patent Number" search box.
(Example: 5976023)

4. Go to the Yahoo! site and enter the word "patent" and
your patent number in the search box. The first result will be a Yahoo! Shortcut that will take you directly to the patent in the USPTO database.
(Example: patent 5976023)

U.S. Patent Databases

The best free U.S. patent databases are:


USPTO Patent Databases

The official United States Patent and Trademark Office site includes access to the full-text of patents from 1976-. Full-page images of patents areincluded from 1790-.

You may need to download a specific TIFF image browser plugin to view the actual page images of the patents (be sure to read the directions.)

Use the "Advanced Search" link on the front page for more complex searches.



Delphion Intellectual Property Network
The Delphion Intellectual Property Network contains searchable bibliographic data (information about the patent) and the complete text of all patents since 1974, and bibliographic text and some images from 1971.
It also includes the full images for patents dated 1790-1971

You may find the Delphion site easier to use than the USPTO site. You must register in order to use the free portions of this Web site.

This site also provides many additional services for a fee.



freepatentsonline
This site includes the searchable text of patents from patent number 4,000,000 (December 1976) to the present. While not as complete as the first two databases, it is easy to search and has some nice display features.

Patent Search Process

The USPTO has developed a seven step patent search process. All the steps can now be done using free Web sources.

1) Search the Index
to the U.S. Patent Classification to begin to get an idea of the relevant classes and subclasses pertaining to your search.

2. Use the U.S.Manual of Classification to further identify the classes and subclasses by which to search.

3. Review the Classification Definitions to further refine your searching by class and subclass or to add additional classes and subclasses to your search. ( More about Classification Definitions. )

4. To make sure you are on the right track, browse sample patent titles and abstracts obtained from your search. Use the
USPTO Patent Databases or the Delphion Intellectual Property Network .

5. Once you are are sure of the relevant classes and subclasses, retrieve a listing of the individual patent numbers from all the relevant classes/subclasses.

Again, use the USPTO Patent Databases or the Delphion
Intellectual Property Network. You should also look at relevant published patent applications

6. Use the U.S. Official Gazette to look at descriptions of each patent to eliminate those not relevant. (OR go directly to Step 7 and eliminate irrelevant patents as you look at the full patent documents.) (More about the Official Gazette. )

7. Use the USPTO Patent Databases or the Delphion Intellectual Property Network to review the complete patent documents.

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