A design patent protects a new, original, ornamental design for an article of manufacture. 35 USC section 171. “Ornamental” means that the design is purely decorative; the patentability is based on its visual aspects. Those aspects are the shape or configuration of an article (like the shape of a bottle or a vase), the surface ornamentation on the article (like a painting on the bottle or vase), or a combination of both. The design must be a design for a specific article; it cannot exist independently of the article. The must be visible during normal use of the article; it cannot be concealed.

Design patents protect only the appearance of the article, not any aspect of functionality. An article that is solely or primarily functional cannot be the subject of a design patent. If, however, the article has an ornamental design but is also functional, it may be the subject of both a design patent and a utility patent.

In order to obtain a design patent, the applicant must file a patent application. The patent application consists of a set of detailed drawings of all views of the article showing the design.  Unlike a utility patent application, a design patent application does not have a detailed written description of the invention but instead contains a sentence describing each drawing. A design application has only one claim, in contrast to a utility application which may have many claims.  In a design application, the claim is simply “the ornamental design for [the article] as shown and described in the drawings.”

The main requirements to obtain a design patent are the same as those for a utility patent. First, the design must be novel (not identical to any design in the prior art). Second, the design must be nonobvious to a designer of ordinary skill in the art. In addition, the design must not be indefinite; the drawings must clearly show the design. The application must also be enabled; that is, the drawings must be sufficient to show a designer of ordinary skill in the art how to make the design.

If a design patent application is allowed, the design patent has a term of 15 years from the date the patent issues. Unlike a utility patent, there are no maintenance fees to keep the design patent in force for its term.

A design patent has several advantages over a utility patent. A design patent application is much easier, less time-consuming, and less costly to prepare than a utility patent application.  Design patent applications proceed more quickly through the Patent and Trademark Office than utility applications. Design patent applications are also more likely to be granted by the PTO than utility applications. This is because a design patent is limited to the specific design shown in the drawings, so there is less prior art for the examiner to consider. However, this advantage is also the main disadvantage of a design patent: because a design patent is limited to the specific design shown in the drawings, the design patent provides narrower coverage (less protection) than a utility patent.

The test for infringement of a design patent is the “ordinary observer test.” Under this test, a design patent is infringed if an ordinary observer would consider the design suspected of infringing and the patented design to be substantially the same. Because a court does not need to construe the claim of a design patent, litigating infringement of a design patent is a little less complicated than utility patent infringement litigation.

In some cases, such as with flatwear, jewelry, fabrics, shoes, or furniture, where the visual aspect of an article is more important than its function, design patents are extremely useful. If there is a strong likelihood that a particular design will be copied, then a design patent is the strongest form of protection.