There are many articles written on advantages of filing a provisional application; however, it may be understood that filing provisional application does come with some disadvantages as well, as summarized below.

• Delay in Issuance of a Patent:

A provisional application cannot result in a patent, and a complete application will eventually have to be filed. Accordingly, the initial filing of a provisional application, instead of the immediate filing of a regular application, essentially delays the issuance of any resulting patent.

• Earlier Publication:

For applications subject to eighteen months’ publication, filing an early provisional application will result in early publication, and thus loss of any trade secret rights relatively early, which could affect funding.

• Higher Total Cost:

The overall cost of initially filing a provisional application and then following up with the filing of an actual application will necessarily be higher than the immediate filing of a regular application, considering the extra official fee and patent attorney’s fee.

• Risk of Inadequate Disclosure:

If the provisional application inadequately discloses the invention eventually claimed in the related actual application, the actual application may not be accorded the priority of the provisional application filing date, and this the whole purpose of filing the provisional application would be nullified.

• Accelerated Foreign Filing Costs:

Filing a provisional patent application starts the one-year period within which foreign patent protection must be applied This leaves the applicant with comparatively tight time frame to fulfil both non-provisional (complete) application filing requirement as well as the foreign filing requirement, and may consequently increase overall cost.

• Potential Prosecution History Estoppel:

If the provisional application is filed with claims and one of the claims is relatively broad, and it is necessary to narrow the claim during preparation or prosecution of the non-provisional or complete application, prosecution history estoppel can result.

So one must take these factors into consideration before make decision to proceed with filing of the provisional application for the invention disclosure. Generally, initially filing a provisional application should be considered:

• when it is desirable to shift the active term of any resulting patent into the future by up to one year; and/or

when it is desirable to delay the cost of examining the application in the Patent Office for up to one year.