In re Global IP Holdings LLC, Appeal 2018-1426 (Fed. Cir. July 5,2019), concerns patent law’s written description requirement, under 35 USC § 112. The patentee is trying to reissue its patent on a carpeted load floor of a car. The patented floor includes thermoplastic components. The components, according to the patentee, ought not have been limited to thermoplastics, rather each should have been any plastic. So, the patentee sought to reissue the patent with a claim to the broader invention. The Patent Office examiner rejected the revised claim. The patent’s written description, explained the examiner, said nothing about plastics other than thermoplastics. The patentee argued to no avail that “the type of plastic used is not critical to the invention and plastics other than thermoplastics were predictable options.” The Board nevertheless upheld the rejection. Regardless of predictability and criticality, said the Board, the patent’s description demonstrates to the relevant reader that the inventors intellectually possessed only thermoplastic components.

On appeal, the Federal Circuit “held that the Board legally erred in its analysis.” Binding precedent, the court noted, explains that the detail in the patent required to satisfy the written description requirement varies depending on, among other things, the predictability of the relevant technology. Ariad Pharm., Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010) (en banc). Contrary to the Board’s pronouncement, said the court, predictability of substituting plastics other than thermoplastics is relevant. Other binding precedent has “held that criticality or importance of an unclaimed limitation to the invention can be relevant to the written description inquiry.” Slip Op. at 7 (citing In re Peters, 723 F.2d 891, 893–94 (Fed. Cir. 1983)). Ariad, said the court, did not reject the Peters holding. Continuing, the court held “that, in some cases, the criticality or importance of the expressly disclosed species [here, thermoplastics] may be relevant to whether an inventor had possession of the claimed genus [here, plastics].” Id. Accordingly, the court vacated the Board’s decision, noting the Board should address predictability and criticality in further examination.

So in some cases, criticality will matter to the written description analysis. And in some cases, predictability will matter to that analysis. The analysis, like a nose of wax, best rests perhaps with advocacy, for the court offers no great guidance. Further, the court never mentions the Supreme Court’s analogous decision in White v. Dunbar, 119 U.S. 47 (1886). White concerned a reissue patent on a method of preserving shrimp in a fabric-lined, metal can where “the claim in the original patent was for placing textile fabric between the can and its contents; whilst in the reissue it is for interposing between the metal can and the shrimps an enveloping material for the shrimps.” Id. at 49–50. The Court explained the importance of the claim and the impropriety of deviating from its terms:

Some persons seem to suppose that a claim in a patent is like a nose of wax which may be turned and twisted in any direction, by merely referring to the specification, so as to make it include something more than, or something different from, what its words express. The context may, undoubtedly, be resorted to, and often is resorted to, for the purpose of better understanding the meaning of the claim; but not for the purpose of changing it, and making it different from what it is. The claim is a statutory requirement, prescribed for the very purpose of making the patentee define precisely what his invention is; and it is unjust to the public, as well as an evasion of the law, to construe it in a manner different from the plain import of its terms. This has been so often expressed in the opinions of this court that it is unnecessary to pursue the subject further.

Id. at 51–52. Said the Supreme Court in concluding the reissue patent in White is invalid: “This is certainly, on its face, a very important enlargement of the claim; and we see nothing in the context of the specification in the original patent which could possibly give the claim so broad a construction.” Id. at 50. In mentioning the context of the specification, the Court did not refer to predictability or criticality, issues the Board must now consider on remand.