The provisional patent application provides the inventor with the all-important priority date.
It offers an extra year of protection (which means instead of 20 years of protection if the patent is granted, it is 21 years).
A 12-month period to more fully develop the product is provided (vital if development includes financing of rather important functions not yet in place.)
It doesn’t require a specific format; in some cases, a design drawing and specification, a paper, or just a handwritten description along with a photograph is all that is filed.
It is relatively inexpensive to file (for smaller entities; for larger entities.)
It requires far less paperwork to be filed.
The provisional patent application is never examined by the U.S. Patent Office, as with a regular patent application. It is only reviewed for formal maters such as to be sure a check is enclosed.
After a provisional application is filed, the invention can be disclosed or sold without fear of losing patent rights so long as a full utility patent application is filed within a year of the filing date of the provisional.
