A provisional patent application is an optional and temporary utility patent application that only lasts 12 months from its filing date. It is never reviewed or examined during its 12-month lifetime and it is never issued as any kind of patent.
The filing costs of a provisional patent application are less than a non-provisional patent application, but overall a provisional application is a more expensive and time-consuming route. because it requires filing a non-provisional patent application.
Although the provisional application requirements are more informal compared to nonprovisional requirements, the safest strategy is to file the same patent application as both a provisional and non-provisional patent application. An incomplete provisional patent application can result in loss of all patent rights in the U.S. and around the world. Complications may arise if the provisional application is not identical to the subsequently filed non-provisional and foreign patent applications, especially because the provisional patent application exceptions exist only in the U.S.
Ultimately, the provisional patent application is a placeholder. It shifts the beginning and end of the 20-year term for patent coverage by one year and gives patent pending status while the inventor does market research and attends to other business needs before the non-provisional and foreign applications are filed.