Searching Application Numbers (continued)

To illustrate how to search application numbers, I will again use File 351, Derwent World Patents Index. Let's take a look at the application number we found in the U.S. patent for the Woosh and search that application number in Derwent.

I start by typing BEGIN 351 in the command text box. Next, I enter the application number in the command text box according to the chart above for a continuing series country.

s an=us 400997

Oh no, I obtained zero patent applications using the application number US 400997. That's strange!

In some countries, however, application numbers are reused. Thus, the application number may refer to different inventions with the only difference for the application number being in the date of application.

Go to the next page.

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