Background
Mallinckrodt plc and its affiliates own three patents covering nitric oxide delivery systems: U.S. Patent Nos. 8,776,794 (the '6794 patent), 9,279,794 (the '9794 patent), and 9,919,118 (the '118 patent). The '6794 and '9794 patents are listed in the FDA's Orange Book for Mallinckrodt's nitric oxide inhalation product; the '118 patent is not. Airgas Therapeutics LLC and Airgas USA LLC submitted ANDA No. 203144 seeking approval of a generic version comprising the ULSPIRA nitric oxide drug product and the ULSPIRA TS delivery system.
Mallinckrodt sued under 35 U.S.C. § 271(a) for commercialization and § 271(e) for the ANDA submission. At trial the case was narrowed to claims 7 and 13 of the '6794 patent, claim 6 of the '9794 patent, and claims 2, 5, 6, and 9 of the '118 patent. A September 8–12, 2025 jury found Airgas infringed all asserted claims willfully, awarding about $3.3 million for the '6794 patent and about $6.1 million for the '9794 and '118 patents combined, without allocating between the latter two.
Airgas renewed its motion for judgment as a matter of law, moved for a new trial, and moved to alter or amend the judgment. Mallinckrodt moved to have the FDA redate Airgas's ANDA approval to no earlier than the latest expiration of the infringed Orange Book patents, and sought enhanced damages and pre- and post-judgment interest.
The Court’s Holding
The court denied Airgas's renewed motion for judgment as a matter of law on all grounds. On the '6794 patent, substantial evidence—including expert testimony that measuring gas concentration at the head unit indirectly verifies the gas source—supported the jury's finding that the accused device verifies gas data. On the '9794 patent, evidence that an interrupted calibration is postponed 24 hours rather than canceled supported infringement of claim 6. The court also upheld willfulness, crediting evidence that Airgas directed its developer to follow a requirements list based on analysis of Mallinckrodt's device, and rejecting Airgas's source-code and subjective-belief arguments.
The court denied the new-trial motion as forfeited and meritless, and denied the motion to alter or amend the judgment. It held that Airgas waived its argument that § 271(e) requires a distinct evidentiary showing by stipulating that the § 271(e) verdict would follow the § 271(a) verdict, and that the commercialized product and the ANDA product are the same. It also held that Airgas waived its section viii carveout defense by omitting it from the pretrial order, and rejected on the merits the claim that § 271(e) does not reach devices because the Orange Book patents claim inventions using nitric oxide.
The court granted Mallinckrodt's redating motion as statutorily mandated by 35 U.S.C. § 271(e)(4)(A). But it vacated the entire damages award: the lump-sum royalty covered the patents' remaining lifetimes, so pairing it with an injunction would double-recover, and the award did not allocate damages between the '9794 and '118 patents. Mallinckrodt remains entitled to past damages for pre-redating infringement of the '6794 and '9794 patents and for infringement of the '118 patent, which the injunction does not cover. Enhanced damages and pre- and post-judgment interest were dismissed as moot.
Key Takeaways
- A stipulation that the § 271(e) verdict will follow the § 271(a) verdict waives any later claim that ANDA infringement required a distinct evidentiary showing.
- A section viii carveout defense must appear in the pretrial order; raising it only in post-trial motions is waived.
- A lump-sum royalty covering a patent's remaining life cannot coexist with an injunction without double recovery, so the court vacated the award.
- Willfulness may rest on evidence that the defendant directed a third-party developer to replicate the patented product, even without knowledge of its own source code.
- An objectively reasonable litigation-inspired defense is no longer a defense to willful infringement.
Why It Matters
The decision shows how § 271(e)(4)(A)'s mandatory redating remedy interacts with damages in Hatch-Waxman litigation: courts must ensure a lump-sum award does not function as a fully paid-up license that makes an injunction duplicative. Patentees seeking both remedies must present damages theories that separate past infringement from future harm.
The ruling also underscores preservation discipline in complex patent cases. Trial-streamlining stipulations bind the parties after an adverse verdict, and defenses such as section viii carveouts must be squarely raised in pretrial orders to avoid waiver.
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