Knobbe Martens
Apr 14, 2020

Ignoring Antecedent Basis in the Claim Results in Reversal of Patentability Determination

Technical Consumer Prods., Inc. v. Lighting Science Grp Corp.

Before Dyk, Chen, and Stoll; Appeal from the P.T.A.B.

Summary:  A term with a narrow antecedent basis in an open ended claim may allow a wider range of prior art references to anticipate

Technical Consumer Products (“TCP”) petitioned for IPR of the claims of the ’968 patent owned by Lighting Science Group (“LSG”), based on anticipation or obviousness in view of the Chou reference.  The Board determined that TCP failed to demonstrate that Chou disclosed a single limitation, referred to as the “H/D limitation,” which required a particular height to diameter ratio of “the heat sink.”  The Board determined that the only way Chou could meet the H/D limitation was to remove an essential element of Chou (the second heat sink) and ruled the claims were not unpatentable.

The Federal Circuit vacated and remanded.  The Court looked to the plain language of the claim and determined that the H/D limitation required “the heat sink” to have a particular ratio of H/D.  The Court further explained that antecedent basis for “the heat sink” could be found in earlier claims and required “the heat sink” to have a particular structure.  The parties agreed that Chou had two structures that functioned as heat sinks, however, only one heat sink in Chou had the particular structures required to be “the heat sink,” as claimed.  LSG argued that both heat sinks in Chou needed to be included in the H/D calculation because both components provided the “heat sink” feature in Chou, and separating them rendered Chou inoperable. The Court rejected this argument because TCP’s theory of anticipation did not require removing the second heat sink. Rather TCP’s theory of anticipation did not include the second heat sink in the H/D calculation because only the first sink had the required structures to be “the heat sink,” as recited by the claim.  In addition, because the claim was open ended the Court explained that it did not preclude the presence of additional heat sinks.  Accordingly, the Court agreed with TCP’s claim construction and position regarding Chou, and remanded to the Board for further consideration.

The Court also noted that the Board reached the opposite conclusion regarding Chou’s disclosure when reviewing a nearly identical limitation in a related patent.  “It is difficult to reconcile [the Board’s] seemingly inconsistent findings” and the Court agreed with the Board’s analysis in the other case.

Editor: Paul Stewart

Written by: Brandon G. Smith & Karen Cassidy