Are District Courts Gun-Shy of Applying the HZNP Meds. LLC v. Actavis Labs. UT, Inc. Indefinite Standard at the Claim Construction Phase?

The Federal Circuit in HZNP Meds. LLC v. Actavis Labs. UT, Inc., 940 F.3d 680 (Fed. Cir. 2019) reiterated that the term “consisting essentially of” permits inclusion of components not listed in a claim, provided that they do not materially affect the basic and novel properties of the invention. Id. at 693. Importantly, the Federal Circuit also found that it was permissible for a District Court to both define the basic and novel properties of a formulation, and then to find that the term “consisting essentially of” was indefinite at the claim construction phase.  Id. at 698-99.  Thus, opening a viable avenue for indefiniteness challenges to claims for which the basic and novel properties are not specifically defined in the patent specification.  Whether the District Courts will pick up the mantle set in HZNP Meds. waits to be seen.  However, District Judge Brian R. Martinotti, of the District of New Jersey, recently deferred ruling on the indefiniteness of “consisting essentially of” during claim construction so that the parties could develop a more complete record.  Par Pharm., Inc. v. Sandoz, Inc., 2020 U.S. Dist. LEXIS 39776 (D. N.J. March 9, 2020).  Sandoz even consented to this approach during the Markman hearing. Id. Judge Martinotti’s decision suggests that Sandoz should provide expert testimony in support of its assertion that the term “consisting essentially of” as used in claim 1 of U.S. Patent No. 9,375,478 is invalid as indefinite under 35 U.S.C. § 112, because the specification of does not disclose the basic and novel properties encompassed by claim.  This ruling further implies that the claim construction phase of a Hatch-Waxman litigation, due to the potential need for expert testimony, is not the most opportune time to press a § 112 defense.  And, as a practical matter, page limitations for a brief during claim construction also counsel that indefiniteness may be a fight better fought elsewhere.  It seems likely, however, that the capacity for making out an indefiniteness defense at the claim construction phase of a case will depend on the specific claim and specific term.