Clients often want to know if they can file a patent application after they started selling, offering for sale, or telling the public about their invention. In most circumstances, the answer is ‘yes’; however, it is not without some caveats.

One drawback is the loss of patent protection in some foreign countries. Therefore, a patent application should be filed in the U.S. before any public disclosure of the invention if the right to file foreign patent applications is to be preserved.

A U.S. patent application can be filed any time within one year of publicly disclosing, publicly using, selling or first offering to sell the invention to another. This “in public use or on sale” in the U.S. results in an inventor losing their right to a patent on their invention and is termed a “statutory bar”.

The “on-sale bar” applies when two conditions are satisfied before the critical date. First, the product must be the subject of a commercial offer for sale. Second, the invention must be ready for patenting.

It seems very little use and very little publicity are required to constitute a “public use.” Typically public use is defined by its natural and intended way. However, private use of one’s own invention is permissible.

There is an exception to the “on-sale” or “public use” bars – an experimental use. The experimental use exception provides that an activity that would place an invention “in public use or on sale” would not trigger the statutory bar if the use or sale was incidental to experimentation.

The preceding discussion is intended for informational purposes only and should not be construed as legal advice. Please contact one of our attorneys to learn more about statutory bar dates or any other aspect of intellectual property law.