Proper Marking of Patents

Often a business takes a product to market at about the same time that patent applications are filed with the U.S. Patent Office. Sadly, if a patent ever issues, several years have passed. Products often evolve over time. My question that I submit for feedback is this: What should a business do as to marking a product that does not completely reflect all of the features of the claims of the patent that ultimately issues from the U.S. patent office? How should patent attorneys counsel clients?

My general answer is this. The patentee should mark products that the patentee reasonably considers covered by the description found in the patent.

The relevant law to consider is found in 35 U.S.C. 287, which is titled “Limitation on damages and other remedies; marking and notice,” (emphasis added). Section (a) states in relevant part that “Patentees . . . making, offering for sale, or selling within the United States . . . or importing any patented article into the United States, may give notice to the public that the same is patented,” (emphasis added). According to this section, this may be done “either by fixing thereon the word ‘patent’ . . . together with the number of the patent, or” . . . affixing the same to the packaging. Thus, there appears to be no explicit requirement to acquire some kind of legal determination (e.g. opinion of counsel, judicial ruling) that a claim of an issued patent actually covers a properly marked product of the patentee.

The purpose of marking is to “give notice to the public” that a patent could be involved with a product. A potential infringer should then seek out a patent attorney to look closer into the matter. If a little over-notice is given, it is not a big deal. The consequence of “over marking” to the patentee seems simple: no infringement will be found and no damages will be awarded to the patentee.