A nonprovisional patent application is normally considered the regular utility patent application. It’s what you file to get the USPTO to review your utility application and hopefully grant your patent. A provisional patent application, on the other hand, does not get reviewed. If done correctly, however, a provisional patent application can be a useful and cost effective tool in obtaining “patent pending” status for a functional invention.
Nonprovisional patent applications must follow a certain format and include, among other things, at least one claim. These are the applications that PTO examiners review and are typically written by patent attorneys. Provisional patent applications, on the other hand, need not follow a strict format. Since their primary purpose is to allow the applicant to get a filing date and patent pending status with respect to what is disclosed, provisional patent applications offer a great deal of flexibility to applicants in disclosing inventions. See a brief explanation of a provisional provided by the PTO.
So, why file a provisional patent application? The decision often boils down to cost. Since provisionals need not adhere to a strict format (and, thus, do not require the expensive fees of a patent attorney or agent), they enable applicants to quickly and inexpensively obtain patent pending status. Provisional applications essentially expire at the 1-year anniversary from the filing date unless a nonprovisional application is timely filed with a priority claim.
What are the risks associated with a provisional patent application? There are several, but one significant risk relates to the level of detail in the disclosure filed, or more precisely, the lack thereof. If you file a nonprovisional within 1 year of the filing date of the provisional, the disclosure in your provisional, including the written description and any drawings, must adequately support the subject matter claimed in the nonprovisional application. You will be able to benefit from the earlier provisional priority date if the claims in subsequent nonprovisional are sufficiently disclosed in the earlier provisional filing. If you add new subject matter that is unsupported by the provisional, then that new matter does not get the earlier provisional filing date, but rather the later nonprovisional filing date.
The PTO does a good job of providing some cautions concerning provisionals. If you’re serious about filing a provisional, make sure to elaborate and expand upon your descriptions and drawings, and include as many alternative approaches as possible to accomplishing the same results.