The U.S. Patent Office offers a reasonably priced ($10.00) service by which an inventor, during the development of an invention, may deposit in the Office a description of the invention. The deposit has no legal effect with respect to securing any patent rights in the invention, but it may serve as evidence of the date of conception of the invention. It is not examined by the Patent Office. The document you deposit is simply kept on file for two years. At the end of that period, the document is then destroyed, unless it is specifically referred to in an action in a then-pending patent application.

According to the Patent Office's documentation, documents deposited in this Program "should provide a more credible form of evidence than that provided by the popular practice of mailing a disclosure to oneself or another person by registered mail." That is the effective purpose of this Program, and its value lies in the fact that the United States accords patent rights to the first inventor -- the first to conceive an invention and reduce it to practice, as far as that fact can be documented -- rather than to the first to file an application for patent protection, as is the case in most other countries.

However, don't get the idea that either this Disclosure Document Program or the alluded-to practice of a registered letter in a safe deposit box will ensure your rights in an invention indefinitely or protect an idea that may lead to an invention at all. Although documentation of the date of conception of your invention can be beneficial to you, there are pitfalls you must be aware of. In the first place, in order for your Disclosure Document to be effective in some future controversy, the disclosure must describe your invention "in sufficient detail to enable a person having ordinary knowledge in the field of the invention to make and use the invention." That level of detail is not too different from the manner of description that will be required in a subsequent patent application. Naturally, some development time would intervene between achieving the ability to describe your invention as the Program requires and achieving, within reason, the "best mode" of the invention that is expected to be disclosed in a patent application. However, in most cases, development time should not be, and is not expected to be, very long, which leads to the second caution.

As an inventor seeking patent protection, you have a duty to be diligent in bringing forth your invention to the benefit of society. The patent system, both in the U.S. and internationally, aims to encourage invention and imposes penalties upon those who seek to hold back or hide inventions and delay progress. A Disclosure Document, should it become material in a patent application, that shows no evidence of development commensurate with the time that the Document shows to have passed, may affect the patentability of your invention.

Finally, the date of filing a Disclosure Document is not the same, and does not afford you the same benefits of priority, as the filing date of a patent application. If your invention is developed to the point that you can describe it sufficiently for someone to make or use it, then perhaps it would be to your advantage to proceed with a patent application, or a provisional patent application, instead of the Disclosure Document.