How are predictability and criticality relevant to the written description requirement?

In In Re Global IP Holdings (Fed. Cir. 2019), the Court of Appeals vacated the Patent Trial and Appeal Board's decision and instructed the Board to consider predictability and criticality to determine whether Global IP's written description satisfies the proper legal standard.

Global IP filed a reissue application in U.S. Patent No. 8,690,233 to replace the term "thermoplastic" with "plastic" in three independent claims. In the reissue application, the inventor filed a declaration that, at the time of the invention, he was aware of the use of plastics other than thermoplastics for the formation of a sandwich-type composite panel with a cellular core.

The Examiner rejected Global's reissue claims, finding that "the specification only supports thermoplastics "and that Global "cannot claim the full range of plastics, which would include thermosetting as well as thermoplastics," thereby introducing new matter. The Board affirmed the Examiner's rejection, explaining that "regardless of the predictability of results of substituting alternatives, or the actual criticality of thermoplastics in the overall invention, [Globla's] Specification, as a whole, indicates to one skilled in the art that the inventors have possession only of the skins and core comprising specifically thermoplastics."

The Court held that the Board was mistaken in its legal analysis of whether Global's specification complies with the written description requirement. The Court stated that "the level of detail required to satisfy the written description requirement varies depending on the nature and scope of the claims and on the complexity and predictability of the relevant technology." The Court further stated that, in addition to predictability, the criticality or importance of an unclaimed limitation to the invention could be relevant to the written description inquiry.

Accordingly, a variation that is predictable to a person of ordinary skill in the art is more likely to be covered by a specification. Moreover, variations of a non-critical invention component are more likely to be covered by the specification.

To discuss the written description requirement of a patent specification, contact TCP Lawl at info@tcplawfirm.com or John Laurence by phone at 917-612-1059.