On Feb 25, 2020, Full Federal Circuit denied Horizon’s petition for en banc rehearing over indefiniteness ruling.
Previously on Oct 10, 2019, Federal Circuit affirmed district court’s decision on obviousness and indefiniteness. You can read the summary “reported here on this blog”. Specifically, District Court & Federal Circuit found the term “consisting essentially of” invalid as indefinite. Court said that “consisting essentially of” covers only the specified elements and those that do not materially affect the basic and novel properties of the claimed invention. Here, “better drying time” is basic and novel properties of the claimed invention & it does not properly defined in the specification. Because two different methods mentioned in the specification for evaluating “better drying time” do not provide consistent results at consistent times. Therefore, POSA would not know under what standard to evaluate the drying rate. Thus, court concluded that the phrase “consisting essentially of” was indefinite based on its finding that the basic and novel property of “better drying time” was indefinite on this record.
In en banc petition, Horizon argued that panel erred in holding that the claims reciting “consisting essentially of” are indefinite because the basic and novel properties that the specification indicates the claimed composition possess are indefinite. Judge Lourie joined by Judges Newman, O’Malley, and Stoll expressed their dissent over denial of petition. Judge Lourie said that better drying time is not in the claim, and it is the claims that the statute requires be definite. The “consisting essentially of” language connotes that those specified are the claim’s essential ingredients, but it is not closed to others. The word “essential” is key. The possibility of inclusion of others, implied by the language at issue here, does not make what is recited and essential indefinite.