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NASEP Research Guide

Engineering Librarian & CAPLA Liaison

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Paula C Johnson
Main Library A403

What is a patent?

A patent is the intellectual property right granted by the U.S. Government to an inventor "to exclude others from making, using, offering for sale, or selling the invention throughout the U.S. or importing the invention into the U.S." for a limited time in exchange for public disclosure of the invention when the patent is granted. In most cases, this is twenty years from the date of application. In some situations, the term of the patent may be extended due to delays in the processing of the application. After the patent has expired, the invention becomes public domain. In addition, patent owners must pay a maintenance fee at 3.5, 7.5, and 11.5 years after issue or else the patent will expire.

Whys & hows of patent searching

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. To do this, conduct a thorough patent search. This will usually involve searching a number of different patent sites, so it's useful to keep a log of all your search activity to avoid duplicate efforts.

See General Information Concerning Patents and Patent Process Overview for more information.

You can begin your search the following way:

1.  Brainstorm keywords to describe your invention, such as synonyms.

2.  Use your keywords to search for a similar match of your invention in Google Patents. The advanced search lets you enter phrases, exclude words, etc.

3.  If you find a similar invention, write down its class and subclass.

4.  Use the class and subclass to search patents and patent applications with the USPTO website classification search. The USPTO website is more current than Google Patents.

[Note: The default search is CPC (Cooperative Patent Classification), which harmonizes the former European Classification (ECLA) and United States Patent Classification (USPC) systems.]

5.  Trace related patents through references.

If you need to look through a large number of patents it might be worthwhile to make an appointment to use the PubWEST database at a Patent & Trademark Resource Center (PTRC). This database is not accessible except through a PTRC workstation.

Patent databases

Accessible to beginners and experts and is updated daily. It contains over than 95 million patent documents from around the world. Supporting information can help you understand whether a patent has been granted and if it is still in force.

Google Patents
Search and read the full text of patents from around the world with this database and find prior art in the index of non-patent literature.

USPTO Patent Full-Text and Image Database
Search all granted patents.

USPTO Patent Application Database
Search all of the applications for patent protection.

from the World Intellectual Property Organization (WIPO)

The Lens
Serves nearly all of the patents in the world as open, annotatable digital public goods that are integrated with scholarly and technical literature along with regulatory and business data.