• A pair of manufacturers are engaged in litigation over the specific design of a solar lightbulb.
  • Design patents are used to protect the appearance of a product rather than the product’s functionality.

The Gerson Companies, a home décor products importer based in Olathe, Kansas, has sued Quanxin Lighting and Electrical (USA) Inc. in federal court in Delaware last month for infringement of a design patent. The patent is directed to the design of a solar-powered lightbulb. In the lawsuit, Gerson has requested monetary damages and an injunction preventing Quanxin USA’s continued sale of the allegedly infringing products.

Most patent litigation in the United States involves a utility patent, which protects the function, chemical composition, or construction of a product. The Gerson case, however, involves a design patent. A design patent protects a product’s appearance rather than its functionality. Once a company has protected the appearance of its product with a design patent, any new product that looks to an ordinary purchaser to be “substantially the same” as the protected appearance may be found to infringe the design patent. As with utility patents, a finding of infringement can lead to an injunction prohibiting the sale of the infringing product and/or the payment of monetary damages to the patent owner.

Gerson has asserted U.S. Patent No. D789,568 against Quanxin USA, an American subsidiary of an international electronics manufacturer based in China. [Note 1]. The asserted design patents are directed to the appearance of a solar lightbulb, as shown below:

It is important to note that the solid lines of the image above represent the claimed design, while the dashed lines represent design elements of the product that are not protected. For example, the shape of the light bulb – which has been used practically since the invention of the incandescent light – is not claimed by Gerson’s design patent. Instead, the design patent claims the base of the lightbulb having a small solar panel, and the shape of the filament.

Quanxin is alleged to manufacture and sell solar lightbulbs having this appearance:

Gerson alleges that Quanxin USA’s infringing products are sold in Home Depot as “Solar Eureka Mercury Bulb” and at Sam’s Club as “Members Mark 6 Mercury Glass Powered Light Bulbs.” Gerson asks the court to find that Quanxin USA infringes its design because not only is Quanxin USA’s product appearance “substantially the same” as Gerson’s protected design, but they are “so similar as to be nearly identical such that an ordinary observer would be deceived by the similarity in the designs.”

Quaxin USA will next have an opportunity to answer the allegations leveled by Gerson. One defense likely to be raised by Quaxin USA is that the design features allegedly protected by Gerson’s design patent are functional and therefore not entitled to design protection.