Searching for the Patently Obvious

By The History Detectives Team
29 June 2009
Category: DIY Investigations

Digging up a patent can shed light on objects you are investigating, and often make for very interesting reading.

If you have an object that has been widely manufactured and you are curious as to when it was invented and released, patents are a great way to establish provenance. A patent is a grant of property rights to a physical invention or innovation and can place an object in context, both historically and technologically.

Patents are also very useful for research as they always reference other related patents. These could be similar inventions or inspirations for the current one.

This week Wes Cowan investigated a more unusual patent - one that appeared to be an invention to do with the Manhattan Project, America’s top secret atomic program. In this case the patent was for a device that separated different isotopes of uranium and the parent documents gave detailed drawings and instructions on how to build this device.

This patent was given to Wes by a contributor, but how do you go about searching for patents for your own research?

A great place to search for patents online is The US Patent and Trademark Office, which approves patents in the US.

The website allows you to examine documents and drawings that are held in a few libraries and in Washington. It has every registered US patent from the first in 1790 to the most recent.

You are able to search by keywords, such as the object’s name and description, or by US patent number. If you do not know the number, find a patent that is similar to what you are after and make a record of its classification/sub classification number. By searching this classification number you will be able to see all related patents and should be able to find your particular patent.

Patents can also be researched at a Patent and Trademark Depository Library or PTDLs spread out over the country. These libraries are great resources giving the public access to copies of patents in several formats.

You can find your nearest PTDL here.

If the patent you are looking for is not registered in the US, you can search for it at the European Patent Office which provides a database of worldwide patents.

Check when the patent was originally submitted as the date patents are approved is typically two years after submission, but in some cases it is even longer.

Have you researched any patents? We would like to know about it. Do you have any tips or sources you think we should know about? Let us know in the form below.


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