One source of uncertainty in the patent system relates to the difficulty in identifying products that are protected with a patent. This paper studies the adoption by U.S. patentees of “virtual patent marketing” namely the online provision of constructive notice to the public that an article is patented. It proposes a simple model of the decision to adopt patent marking and empirically examines factors that affect adoption.
Data suggest that about 12 percent of patent holders overall provide virtual marking information (and perhaps about 25 percent of commercially active assignees). Econometric analysis suggests that the most discriminant factor of the adoption of virtual marking is the size of the patent portfolio. The likelihood of adoption increases with portfolio size, consistent with evidence that firms with a larger patent portfolio are more likely to be infringed.