The United States Patent and Trademark office states: Since June 8, 1995, the United States Patent and Trademark Office has offered inventors the option of filing a provisional application for patent which was designed to provide a lower-cost first patent filing in the United States. Applicants are entitled to claim the benefit of a provisional application in a corresponding non-provisional application filed not later than 12 months after the provisional application filing date.
Under the provisions the corresponding non-provisional application would benefit in three ways: (1) patentability would be evaluated as though filed on the earlier provisional application filing date, (2) the resulting publication or patent would be treated as a reference as of the earlier provisional application filing date, and (3) the twenty-year patent term would be measured from the later non-provisional application filing date. Thus, domestic applicants are placed on equal footing with foreign applicants with respect to the patent term. Inventors may file U.S. provisional applications regardless of citizenship.
Unlike regular patent applications:
• Provisional applications are not examined on their merits.
• The benefits of the provisional application cannot be claimed if the one-year deadline for filing a non-provisional application has expired.
• It is recommended that the disclosure of the invention in the provisional application be as complete as possible.
• The inventor(s) named in the provisional application must have made a contribution to the invention as described. If multiple inventors are named, each inventor named must have made a contribution individually or jointly to the subject matter disclosed in the application.
Louis Paul of Louis Paul and Associates points out that the provisional patent sets the flag in the mountain and sets a date of invention in the patent office. It is not examined but does establish a priority date. Louis cautions that while the provisional patent application is not as formal as the regular patent application it must meet requirements of enablement that is it must disclose an operative invention. The provisional application is used primarily to fix the data and allow the inventor time to develop the invention further.