Best Mode: District Court Improperly Invalidated Patent that Mis-Identified Best Mode

Green Edge Ent. LLC v. Rubber Mulch Etc. LLC (Fed. Cir. 2010)

You might guess from the names of the parties that the subject matter of the dispute is rubber mulch. Green Edge's patent covers a synthetic rubber mulch that is shaped and colored to imitate a natural mulch. In its patent application, Green Edge indicated that a variety of systems could be used to add color to the rubber, but the application also spelled out one particular "VISICHROME" system by Futura Coatings as being the "most preferred" system. It turns out that Futura Coatings never made or sold system under the name of VISICHROME. Rather, the product Green Edge should have identified was "Product Code 24009." The name VISICHROME apparently came from a sales letter from a Futura Vice President who had referred to a VISICHROME system.

Best Mode: During the infringement litigation, the Eastern District of Missouri court held the patent invalid for failure to disclose the best mode under 35 USC § 112 – finding that VISICHROME did not exist and "that Green Edge had concealed the best mode by disclosing 'a misleading, non-existent name instead of the number' when no similar product was available on the market."

Section 112 of the patent act requires that the patent specification "set forth the best mode contemplated by the inventor of carrying out his invention." Federal Circuit precedent has held that such a "best mode" need only be described if the inventors subjectively possessed a best mode on the filing date of the application. Even then, the question is whether the inventor "concealed" the preferred mode from the public.

The second prong asks whether the inventor has disclosed the best mode and whether the disclosure is adequate to enable one of ordinary skill in the art to practice the best mode of the invention. The second inquiry is objective; it depends upon the scope of the claimed invention and the level of skill in the relevant art.

Although not suggested by the statute, the best mode requirement is generally examined on an element-by-element basis. Here, Green Edge clearly had a preferred approach for coloring the rubber pieces and thus was required to disclose that "best mode."

On appeal, the Federal Circuit reversed – holding that the best mode had not been objectively concealed. The court's reasoning was that a competitor looking for "VISICHROME" might have been able to find it around the time of the invention since at least one Futura Coatings executive had been using that name in sales letters.

The disclosure might have, at the time the application was filed, been specific enough to describe the colorant so as to enable a person of ordinary skill in the art to make the claimed product using Futura's 24009 product. The application for the '514 patent was filed in October 1997, and [the Futura VP's] letter describing Futura's "Visichrome" colorant system was written in July 1997. Thus, despite [the VP's] inability to remember why he used the term "Visichrome" in his letter, it is at least possible, even likely, that in October 1997, at the time of filing, someone contacting Futura to obtain the "Visichrome" colorant system would have received a response similar to Jarboe's letter of that July.

In the end, the court held that summary judgment was inappropriate. On remand, a jury could still find the patent invalid on best mode.