Indefiniteness Is In the Eye of the Beholder

A recently designated precedential decision from the PTAB, McAward,¹ and a recent Federal Circuit decision, BASF Corporation,² highlight the differences in the USPTO’s and the court’s interpretation of the definiteness requirement.

In McAward, the PTAB explicitly stated that it rejects the Nautilus standard for determining indefiniteness, and instead applies the Packard approach.³ Nautilus requires that claims be “viewed in light of the specification and prosecution history [to] inform those skilled in the art about the scope of the invention with reasonable certainty,”⁴ whereas Packard requires that “[a] claim [be found] indefinite when it contains words or phrases whose meaning is unclear.”⁵ In its analysis, the Board reasoned that the USPTO “bears responsibility for testing claims for indefiniteness prior to issuance”⁶ and should evaluate the claims in their broadest reasonable interpretation for words or phrases whose meanings may be unclear. The Board asserted that interpreting the claims as broadly as reasonable during prosecution allows the USPTO to ensure that proposed patent claims are “clear, unambiguous, and drafted as precisely as the art allows.”⁷ The Board also recognized that the “broadest reasonable interpretation” standard differs from the standard used in the courts during patent litigation proceedings. The Board concluded that the USPTO’s to claim construction “naturally results in an approach to resolving questions of compliance with § 112 that fundamentally differs from a court’s approach to indefiniteness.”⁸ The Board thus chose not to adopt the Nautilus standard during patent examination, citing the opportunity for claim amendments during prosecution as justification for a lower threshold for ambiguity for the USPTO compared to the courts.

In McAward, the claims appealed to the Board were directed to a water detector “configured to be reliably installed by an untrained installer or a homeowner and to not require the services of a plumber or electrician to perform installation, thereby permitting widespread and cost effective adoption.” The Examiner rejected the claims under 35 U.S.C. § 112(b) as being unclear and indefinite, stating that “the claim language does not provide any structure to the apparatus or system that would allow it to be configured to function as described in the claims.”⁹ The Board affirmed the Examiner’s rejection.

By contrast, the Federal Circuit decision in BASF v. Johnson illustrates the definiteness standard set forth in Nautilus. The claims at issue in BASF v. Johnson are directed to a catalyst system for treating exhaust gas, comprising materials “effective for catalyzing” or “effective to catalyze” a specific reaction.¹⁰ BASF Corporation, the patentee, sued Johnson Matthey Inc. for infringement. Johnson argued that the “effective for catalyzing” and “effective to catalyze” language is indefinite and filed an expert declaration stating that the patent does not define a minimum level of function or particular measurement standard to define the “effective” limitation. The district court agreed with Johnson and ruled the claims invalid for indefiniteness.

Upon appeal by BASF, the Federal Circuit reversed the district court judgment of invalidity based on indefiniteness. The Federal Circuit first set forth the standard of review under Nautilus: “would the ‘composition… effective to catalyze’ language, understood in light of the rest of the patent and the knowledge of the ordinary skilled artisan, have given a person of ordinary skill in the art a reasonably certain understanding of what compositions are covered?” ¹¹

Under this analysis standard, the Federal Circuit ruled that the district court erred by failing to consider that the specification teaches a specific arrangement of the catalysts, and thus any known catalysts can be used as long as they can fulfill their “claimed role in the claimed architecture.”¹² The Federal Circuit further states that the specification and the claims of the patent provide descriptions of the chemical reactions and their improvements, using the particular arrangement of catalysts, as well as exemplary compositions that are “effective” to catalyze the reactions. The Federal Circuit also noted that the extrinsic evidence, i.e., expert declarations, could not support a finding of lack of reasonable certainty because Johnson’s expert himself stated that materials capable of performing the claimed reactions (i.e., catalysts) were known in the art at the time of the invention, and that objective tests to determine effectiveness of the catalysts were available and well-known at the time. The Federal Circuit found that the expert declaration confirmed the relevant skilled artisan would “reasonably understand what level (under what conditions) would qualify a composition as a claimed catalyst.”¹³ Thus, the Federal Circuit ruled that in view of the intrinsic and extrinsic evidence, there is no support for a ruling of indefiniteness of the claims in question.

McAward and BASF v. Johnson illustrate the different approaches to the definiteness standard employed by the Board versus the Federal Circuit. Claims in the pre-issuance stage, which have the opportunity for amendment, are given their broadest reasonable interpretation for words or phrases whose meanings may be unclear, while patented claims are evaluated based on whether a person of ordinary skill in the art can understand the claim in view of the specification and prosecution history. Thus, the different approaches to claim construction result in different interpretations of indefiniteness.