The United States has a significant gap in its intellectual property laws. Every other major country has a system of industrial-design registration, which provides quick and relatively inexpensive protection for nonfunctional product designs. Under these systems, a new design for a chair, a pair of sunglasses or the door of a microwave oven can be protected from the outset by making a relatively simple filing.

The United States has no such system. As an alternative, owners of successful designs have long sought protection under the trademark laws. But doing so has become increasingly difficult. Three recent decisions, which denied protection to designs that were the subject of “incontestable” trademark registrations, summarize why relying on trademark law to protect product designs is not a sure thing.