Once your provisional patent application is filed with the U.S Patent Office, you have exactly twelve months to apply for a full patent in order to claim the earlier filing date as the date of invention. This can be done in two ways:

1. Filing a full patent application that claims the provisional patent’s filing date.


2. Filing a petition to convert the provisional patent into a full patent application.

Although both of these actions result in a full patent application, the term of the patent will differ. With the first option, your patent term will be measured from the date that your full patent filed. With the second option, the term will be measured from the filing date of the provisional patent. Thus, with the first option, you are effectively able to add up to an extra year to your patent term.

In order for the full patent application to have the benefit of the provisional patent’s filing date, the description of the invention in the provisional patent application must be similar in sufficient detail to the invention as described in the full patent application. In other words, the U.S. Patent Office must be able to confirm that the invention described in your provisional patent application is the same as the invention covered in your full patent application.

Therefore, it is important to be as thorough as possible when disclosing your invention in the provisional patent application. For this reason, the U.S. Patent Office highly recommends that you include professional illustrations of your invention with your provisional patent application.

In addition, since a provisional patent application is not reviewed by the U.S. Patent Office, the filing of a provisional patent does not guarantee that you will actually be awarded a full patent. Instead, the full patent application is evaluated on its own merit. Only if the full patent application is approved will the provisional patent’s filing date be used as the priority date of the patent.