Unlike the mandatory written description requirement for U.S. patents outlined in 35 U.S.C. § 112, drawings are only required when necessary for the understanding of the subject matter sought to be patented (35 U.S.C. § 113). While a written description—the patent specification—may indeed describe an invention in full, clear, concise and exact terms (35 U.S.C. § 112), there is much to be said for a detailed rendering, as expressed in the well-worn English language idiom, “A picture is worth a thousand words.” Today, nearly all U.S. patent applications are submitted with illustrations.
But there was a time when the United States Patent and Trademark Office (PTO) required drawings. Upon its inception in 1790, every patent application had to be accompanied by an illustration. Additionally, the Office required inventors to submit a model with the patent application, which were mini (1 foot), three-dimensional mockups of an invention (Patent Models Index: Volume 1: Listings by Patent Number and Invention Name, by Barbara Suit Janssen). Early patent drawings differ significantly from today’s drawing, from intricate shaded and textured images to (primarily) sparse black-and-white line drawings. Such changes in patent drawings are the result of adjustments in patent application rules, writes Wired author Alexandra Chang (“The History (and Artistic De-Evolution) of Patent Drawings”). The PTO no longer requires that patent applicants hire a professional draftsperson and, in 2000, the PTO adjusted its rules to focus on drawings that communicate the invention to the Examiner and to focus on readable drawings in published applications and patents. While a modern drawing does have to explain an invention, says Chang, it doesn’t have to do so in an especially beautiful way. Perhaps one exception to the present, plain-spoken drawings are plant patents, which, should be artistically and competently executed and, unlike utility patent drawings, do not include view numbers and reference characters unless required by the examiner. Plant drawings must disclose all distinctive characteristics of the plant and may be in colors, particularly if color is a distinguishing characteristic of the new variety (MPEP § 1606).
The current pared-down approach to patent illustration is not without specific guidelines, though, which are outlined in the Manual of Patent Examining Procedure (MPEP § 608.02). For design and utility applications, black and white drawings are normally required, specifically India ink, or its equivalent that secures solid black lines. Black and white photographs, including photocopies of photographs, are not ordinarily permitted, but the PTO will accept photographs in utility and design patent applications if photographs are the only feasible medium for illustrating the claimed invention. Color drawings and photographs can be permitted in design applications and, on occasion, permitted in utility applications upon petition if the only practical medium to disclose a claimed invention. Color drawings and photographs are not permitted in international applications.
Patent drawings are usually formatted on 8.5 by 11 pages or “sheets.” The PTO requires the sheets to be numbered, as well as the differing views of the invention. View numbers are preceded with the abbreviation, “FIG.” Reference characters, arrows, and lead lines are used for clarifying details outlined in the specification. Drawings are not required to be drawn to scale, though the drawing must be large enough to adequately show an invention reduced by two-thirds. Shading, legends, and copyright notices, though uncommon, can be included.
A quick Internet search for “patent drawings” brings PTO specifications into focus, particularly the contrast between early and modern patent illustrations. For example, take a look at United States Patent No. 1,290,847, issued January 7, 1919, and titled “Airship” and compare it to United States Design Patent No. D618677S1, issued June 29, 2010, and titled, “Electronic Device.” Technology and time differences aside, “Airship” drawings are detailed images of an open-air flying machine, complete with pilots with goggles and a backdrop of countryside scenery, along with the inventors’ names, George C. St. Louis and Calvin Pearson, in elaborate script. Apple’s “Electronic Device” images, however fabulous the iPhone is, are simple line drawings—with a bit of shading and typeset number references—of its now very familiar rectangle-with-rounded-corners shape. The difference in illustrative approach is striking.
There are those who yearn for the lost art of patent drawings. To be sure, the detailed images from the early 1900s are appealing to look at, which may explain the cottage industry of framed vintage patents. However, it can be argued that today’s utilitarian, technical approach to patent drawings more aptly protects the nature of invention in the ever-expanding world of intellectual property.