IP Law Daily BASF’s catalytic converter patent was not invalid for indefiniteness
Monday, November 20, 2017

BASF’s catalytic converter patent was not invalid for indefiniteness

By Cheryl Beise, J.D.

The federal district court in Wilmington, Delaware, erred in finding that a patent directed to a dual coating systems for performing catalytic conversion of exhaust owned by BASF Corporation was invalid for indefiniteness, the U.S. Court of Appeals for the Federal Circuit has held. The evidence did not support the finding that a person of ordinary skill in the relevant art would not understand language describing compositions "effective" to catalyze nitrogen oxides and ammonia oxidation. The district court’s judgment of invalidity in favor of BASF competitor Johnson Matthey, Inc., was reversed and the case remanded (BASF Corp. v. Johnson Matthey, Inc., November 20, 2017, Taranto, R.).

BASF Corporation owns U.S. Patent No. 8,524,185 (the ’185 patent), entitled "Integrated SCR and AMOx catalyst systems," is directed to systems for performing catalytic conversion of nitrogen oxides (NOx) in an exhaust gas stream. The patent claims a partly-dual-layer, two-zone coating system, arranged on a substrate over which exhaust gas passes—a coat along the full length of the substrate containing "a material composition B effective to catalyze selective catalytic reduction (SCR) of NOx"; and beneath part of that coat, on the outlet end of the gas passage, a partial-substrate undercoat containing "a material composition A effective for catalyzing NH3 oxidation" (ammonia oxidation, or AMOx). The specification sets out the specific stoichiometric chemical reactions for the catalysts. It identifies a variety of materials that can be used for "material composition A" (e.g., "refractory metal oxide[s] containing alumina, silica, zirconia, titania, ceria") and "material composition B" (e.g., an "aluminosilicate molecular sieve [with] one of the crystal framework types FAU, MFI, MOR, BEA"). The specification also includes various examples of how catalyst layers are prepared and how they perform under practical engine conditions in comparison to the prior art.

In 2014, BASF sued competitor Johnson Matthey Inc., for infringement of the ’185 patent. The district court concluded that the "effective for catalyzing"/"effective to catalyze" language is indefinite and entered judgment of invalidity on all claims. According to the district court, each claim failed to limit the "material composition A" or the "material composition B" to any specific materials, instead utilizing the functional term "effective" to purportedly define the compositions. BASF appealed.

The Federal Circuit reviewed the district court’s indefiniteness ruling de novo, noting that the Supreme Court in Nautilus, Inc. v. Biosig Instruments, Inc. held that a patent claim is indefinite if, when "read in light of the specification delineating the patent, and the prosecution history, [the claim] fail[s] to inform, with reasonable certainty, those skilled in the art about the scope of the invention." 134 S. Ct. 2120, 2124 (2014).

Thus, the issue on appeal was whether the "composition … effective to catalyze" language—understood in light of the rest of the patent and the knowledge of the ordinary skilled artisan—would have given a person of ordinary skill in the art a reasonably certain understanding of what compositions are covered. After reviewing the record, the Federal Circuit concluded that "[t]he district court’s reasoning supplies no basis to answer that question in Johnson’s favor."

Functional language. The district court expressed concern about the functionality of the claim language. However, the Nautilusreasonable certainty standard does not exclude claim language that identifies a product by what it does. Moreover, the Federal Circuit has long held that the indefiniteness does not preclude defining a particular claim term by its function. What is needed, the appeals court explained, "is a context-specific inquiry into whether particular functional language actually provides the required reasonable certainty."

Knowledge of relevant skilled artisan. The district court next found that the claims do not "recite a minimum level of function needed to meet this ‘effective’ limitation nor a particular measurement method to determine whether a composition is ‘effective’ enough to fall within the claims." However, the district court failed to define what "recited" information a person of ordinary skill in the art would need to be given to understand, with reasonable certainty, whether a composition is "effective to catalyze" the SCR (of NOx) or AMOx reactions. The district court’s conclusion was "entirely unsupported, whether by reference to the specification or other intrinsic evidence or by reference to extrinsic evidence," the Federal Circuit observed.

The claims and specification provide that any known SCR and AMOx catalysts can be used as long as they play their claimed role in the claimed architecture. They further provide exemplary material compositions that are "effective" to catalyze the SCR of NOx and the oxidation of ammonia, disclose the chemical reactions that define the "SCR function" and "NH3 oxidation function," and illustrate through figures, tables, and accompanying descriptions how the purportedly novel arrangement of the catalysts results in improved percent conversion of ammonia and improved nitrogen selectivity.

The Federal Circuit was not persuaded that a relevant skilled artisan, reading the claims in light of the specification, "would lack reasonable certainty as to what compositions are ‘effective to catalyze’ the reactions at issue—or, equivalently, what compositions are SCR catalysts or AMOx catalysts—in the context of this patent." The ’185 patent’s asserted advance over the prior art was in the partly-dual-layer arrangement to create a two-phase operation for performing the identified conversion processes, not in the choices of materials to perform each of the required catalytic processes.

The extrinsic evidence also failed to show that a person of ordinary skill in the art would lack reasonable certainty as to what compositions would qualify as an SCR or AMOx catalyst in this context. Both parties’ experts agreed that materials capable of performing the claimed reactions were known in the art at the time of the invention and that objective tests to determine the effectiveness of the catalysts in question, e.g., percent conversion, were available and known as well.

Because the record did not contain intrinsic or extrinsic evidence to support indefiniteness, the district court’s judgment was reversed and the case remanded.

The case is No. 2016-1770.

Attorneys: Deanne Maynard, Counsel (Morrison & Foerster LLP) for BASF Corp. Douglas E. McCann (Fish & Richardson, PC) for Johnson Matthey Inc.

Companies: BASF Corp.; Johnson Matthey Inc.

MainStory: TopStory Patent FedCirNews

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