What you need to know about provisional applications

Many inventors, for whatever reason, are under the impression that a provisional application is some sort of fast and cheap way of filing an application.

Before you take this route, I recommend that you educate yourself before you or someone prepares your provisional application.

Risks of Filing Provisional Patent Applications

Some people feel that the provisional application is an easy and inexpensive way to obtain a filing date and some patent rights, but they are usually unaware of the risks and downside.

These patent applications never issue into a patent, and can never be enforced to prevent someone from copying your invention. 

If a regular, complete, patent application is prepared and filed within a year from the filing date of the provisional patent application, the regular patent application may be entitled to the filing date of the provisional patent application, but only if the provisional application meets best mode and enablement requirements.  

In order to be valid, the provisional application must comply with the first paragraph of section 112 of the patent law. 
If the provisional application does not comply with this section, it will be invalid and will not provide a filing date. 

Foreign applications must be filed within one year of the filing date of the provisional application in order to be entitled to the filing date of the provisional application. 

If provisional applications are used, it is recommended that they be drafted as if they were a full regular patent application to make sure that they comply with the best mode and enablement requirements. 

For example, if an applicant in a provisional application says "the switch is a MOSFET"  where no specific type is essential, and then a patent attorney preparing a regular patent application corrects this by saying "there is a switch, it can be any type but in some embodiments it is a MOSFET",  be prepared for an argument during litigation that unless a competitor uses a MOSFET, there is no infringement regardless of what is recited in the claims because the inventor clearly only contemplated use of a MOSFET.

If there is no budget for a full application and a provisional application is filed, a full application drafted by a patent attorney should be filed as soon as possible after the provisional application is filed.  Thus, in the event that the provisional application does not comply with the provisions of 35 U.S.C. ' 112, first paragraph, it may be possible to prepare the regular application before any important deadlines are missed.  

With these risks in mind, provisional patent applications that are not drafted as full regular patent applications can still be useful for obtaining "patent pending" status if there is simply no budget for a full patent application.

A poorly written provisional patent application may be fatal to getting a patent for your invention.
If a provisional application is poorly written and leaves out sufficient written description of the invention, particularly on how to make and use the invention, the early priority date may not be relied upon.
Its always best to consult with an experienced patent agent and have a complete provisional patent application filed to avoid these types of issues.