Processing All Things Federal Circuit
August 11, 2023 - Last Week in the Federal Circuit

Last Week In The Federal Circuit (July 31 – August 4): Federal Circuit Reminds To Focus On The Claims


This week’s case of the (recent) week could serve as a crash course in several areas of patent law. It touches on Hatch-Waxman litigation and the Orange Book, claim construction, anticipation/obviousness, written description and enablement, infringement, induced infringement, and a parallel IPR proceeding. But as discussed below, the most interesting aspects of the decision relate to safety and efficacy for claimed treatments, the effect of ongoing IPR proceedings, and anticipation of product-by-process claims.

Precedential opinions: 4

Non-precedential opinions: 3

Rule 36: 0

Longest pending case from argument: Bufkin v. McDonough, No. 22-1089 (178 days)

Shortest (non-Rule 36) pending case from argument:Teradata Corporation v. SAP SE, No. 22-1286 (54 days)

Case of the (recent) week: United Therapeutics Corp. v. Liquidia Techs., Inc., Nos. 2022-2217, 2023-1021 (July 24, 2023) 

Panel: Judges Lourie, Dyk, and Stoll with Judge Lourie writing the opinion

You should read this case if: you have a matter involving (1) pharmaceutical patents where a party wishes to read safety and efficacy requirements into the claims or (2) allegations of induced infringement when a parallel IPR decision has issued but is still subject to appellate review.

United Therapeutics holds a New Drug Application for an inhaled solution for treating pulmonary hypertension. Liquidia later filed a § 505(b)(2) New Drug Application, one of two abbreviated approval pathways under the Hatch-Waxman Act (the other being an abbreviated new drug application). United asserted that Liquidia’s proposed competing solution infringed two United patents, one claiming a method of treatment and the other a composition. After a bench trial, the district court found the method patent valid and infringed and the composition patent infringed but invalid. The parties cross-appealed and the Federal Circuit affirmed.

On appeal, Liquidia argued that the district court erred in refusing to construe the claim term “treating pulmonary hypertension” to require that the treatment be safe and effective. The parties’ experts agreed that a known subset of patients would not benefit from the claimed treatment. Even so, the Federal Circuit agreed it was improper to read safety and efficacy requirements into the claims where not explicitly included. “Questions of safety and efficacy in patent law have long fallen under the purview of the FDA.”

This argument spilled over into enablement and written description. Liquidia argued that because it was known that some patients would not benefit from the claimed treatment, the disclosure failed to enable the full scope of the invention. But the claims simply required improving hemodynamics, not necessarily being a net positive for a patient. Whether studies showed some patients had “increased mortality, yet showed ‘improvement in a patient’s hemodynamics,’ may be an issue for the FDA. But our focus is on the claimed invention.” The Federal Circuit thus affirmed that the method patent was enabled. Similarly, with written description, Liquidia’s argument that a patent needs separate disclosure “for each individual variant of the condition” likewise failed. “A subset of unresponsive patients is not analogous to unsupported species in a generic claim to chemical compounds.”

This case also clarifies the effect of parallel IPR proceedings on a finding of induced infringement. The PTAB issued a written decision finding the treatment method patent invalid. Liquidia argued this precluded intent to induce infringement. But the appeal of the IPR decision was ongoing. The Court held that “[a] pending, non-final litigation does not negate an intent to infringe that is otherwise supported by the evidence.” 

One final area of interest relates to the other asserted patent involving a composition. The Federal Circuit refers to it as a “product-by-process” claim; it recites a composition prepared by a specific process. The district court found that a prior reference disclosed the composition as claimed. United argued that the reference did not teach that the prior-art composition was made using the process recited in the claim. The Federal Circuit was unpersuaded:  “As these claims are product claims, they are anticipated by a disclosure of the same product irrespective of the processes by which they are made.”

So remember, get your prescription advice from a doctor or the FDA, not patent lawyers.