Since June 8, 1995, the United States Patent and Trademark Office (USPTO) 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, according to the USPTO website.
“Technically, there is no such thing as a ‘provisional patent.’ The patent law provides for a ‘provisional application,’ which isn’t subject to some of the formal requirements for a regular patent application. 
A provisional application, however, is not intended to, itself, provide any enforceable rights,” says Michael Lechter — a practicing attorney and the author of “Protecting Your #1 Asset, Creating Fortunes from Your Ideas, An Intellectual Property Handbook” — in his Inc. column online.
A provisional application for patent (provisional application) has a pendency lasting 12 months from the date the provisional application is filed, according to the USPTO. The 12-month pendency period cannot be extended.Therefore, an applicant who files a provisional application must file a corresponding non-provisional application for patent (non-provisional application) during the 12-month pendency period of the provisional application in order to benefit from the earlier filing of the provisional application.
A provisional application, which may not be filed for design inventions, allows filing without a formal patent claim, oath or declaration, or any information disclosure (prior art: in most systems of patent law, prior art constitutes all information that has been made available to the public in any form.) statement. It provides the means to establish an early effective filing date in a later filed non-provisional patent application. It also allows the term “Patent Pending” to be applied in connection with the description of the invention.
Lechter cautions:
— A provisional application is not examined by the Patent and Trademark Office (PTO) and is automatically abandoned 12 months after filing.
— It does not itself ever mature into a patent. For a patent to issue on the subject matter described in the provisional, a regular application claiming priority on the provisional application must be filed within a year of the provisional.
— A PPA costs $125 ($250 for a large company).
— There are reasons why you might want to file a provisional application, but saving money is not one of them. While you can delay a portion of the expense of preparing a regular application (the cost of preparing a full set of claims), the only time that you save money by filing a provisional application is if you ultimately decide not to pursue patent protection before you file the corresponding regular application.
So what have we learned? A provisional patent application is not a patent, but a document that allows for an early effective filing date in a later filed non-provisional patent application and let’s the creator use the term “Patent Pending” in relation to the product. You will still need to file a corresponding non-provisional application before the 12-month pendency of your provisional application expires, as a provisional application will not mature into a patent filing. A provisional patent application is only a part of the process, so even though it’s a cheaper and faster way to get your idea in the office, you will still need a non-provisional patent if you continue to pursue your idea.