The priority date is a critically important feature because it establishes the date when the disclosed invention was first made practical. To rely on the priority date, within one year of filing the provisional application the inventor must file a regular patent application, basing it on the information contained in the provisional application.

What this provides is a one-year cushion. During that year, as the product or concept is further developed, additional provisional applications can be filed and relied upon for the priority date. Failure to file within one year of the original or subsequent provisional applications results in the loss of the priority date.

Because the provisional application will not be substantively examined, claims defining the scope of the invention are unnecessary. But to rely on the priority date of the provisional, the disclosed invention has to support the broadest invention that is ultimately claimed in the disclosed patent grant.

A description of the invention and supportive drawings are also part of the provisional application. A provisional application can even protect a theoretically working model that is not yet reduced to practice. Just as the filing fees are substantially reduced, so are the legal fees because far less work is involved.

Development should be continued with the goal of filing for a regular patent within one year of the priority date always foremost. And as the development continues, it’s often wise to file additional, more current provisional applications. The provisional application is not a substitute for a regular patent application, which should be filed as soon as possible. We recommend that the provisional application be drafted with all the details available and then filed as soon as possible to obtain a priority date.

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Howard M. Cohn & Associates has extensive and varied experience in all aspects of Intellectual Property law, with a unique specialty in patent and trademark preparation and prosecution. Schedule an appointment or call us at 800-613-1067.