A design patent protects the ornamental look of a product. To be valid, a design patent cannot protect functional or utilitarian aspects of a product - only the ornamental appearance.
A design patent application requires formal illustrations from a dedicated patent illustrator.
Design patents are less expensive to obtain and are more likely to be allowed by the U.S. Patent Office. Design patents can be an attractive option for a small business commercializing a product with a unique three-dimensional look. If a product has novel functionality and a novel appearance it is protectable under a utility patentand a design patent.