U.S. design patents had hit rock bottom a few years ago in terms of enforcement in the courts (they were too easy to design around and not so easily enforced). But the pendulum is swinging back, and U.S. design patents are becoming a very useful tool in one’s IP asset portfolio.

This conclusion was underscored in the Federal Circuit’s Pacific Coast Marine Windshields Limited v. Malibu Boats, LLC decision earlier this month. Plaintiff/patent owner Pacific Coast has a design patent comprising a boat windshield with four vent holes. The competitor-defendant design has three vent holes. Of significance to the decision, Pacific Coast’s originally filed design also comprised two vent holes and no vent holes in the single design patent application. But the U.S. Patent Office deemed such alternative designs to be separate inventions and required Pacific Coast to elect which design it wanted to prosecute in that application. Pacific Coast elected the four-vent-holes design and surrendered the rest.

The trial court granted summary judgment to defendants because it concluded that Pacific Coast surrendered any broader claim scope in the election process. But the appellate court didn’t agree, and held that as a matter of law the surrendered designs were only those with two vent holes or no vent holes, not three vent holes. So the appellate court remanded the case to the district court to determine whether the three-vent-holes design is a “colorable imitation” of the four vent holes design. Such “strict construction” of the scope of surrendered material may allow a broader interpretation of design patent claims. Design patent owners, take note.