The United States Court of Appeals for the Federal Circuit recently held in Great Northern v. Henry Molded Products that a patent on a product for supporting rolls of material, such as cellophane or steel, was invalid for failing to disclose the "best mode." The plaintiff, Great Northern, sold a product called ROLLGUARD II and obtained a patent. Defendant, Henry Molded Products, sold a similar product called STAKKER and obtained a patent. Great Northern sued Henry, and both patents were in-suit.
The law requires that a patent "set forth the best mode contemplated by the inventor of carrying out his invention." The "best mode" rule, as applied by the court, requires that "production details" that relate to the "quality or nature" of the invention, but which are routine (i.e., known to those of ordinary skill in the art), need not be disclosed in the patent. However, non-routine "production details" must be disclosed.
The STAKKER product (made from molded pulp) could not be produced without diamond-shaped indentations being added during production to maintain its shape. These indentations, however, were not disclosed in Henry's patent, and Henry produced no evidence to show that the diamond-shaped indentations were routine. Since this "production detail" was not put in the patent, it was invalidated.
Great Northern teaches two lessons. First, non-routine "production details" relating to the "nature and quality" of the product must be disclosed. Second, diligence should be exercised by the inventor(s) to ensure that improvements to the invention prior to the patent application filing date are disclosed to the patent attorney for evaluating any "best mode" issues.