Recent Hatch-Waxman Rulings Address Orange Book Delisting, Pleading Standards, and Expert Testimony

In the wake of the Federal Circuit’s 2024 Orange Book delisting decision in Teva v. Amneal, Hatch-Waxman practitioners have been left to grapple with several unanswered questions. Although the decision clarified what is required for some patents to qualify for listing in the Orange Book, the case was voluntarily dismissed before downstream effects of the delisting could come to a head in the litigation. Questions remain about what happens in ongoing Hatch-Waxman litigation when the asserted patents are delisted.

If all asserted patents are delisted during litigation, dismissal of the corresponding infringement claims has some logical appeal. After all, if the patents had not been listed improvidently in the Orange Book, there would not have been any legal basis to initiate the litigation. One court has appeared willing, at least in theory, to allow declaratory judgment claims to survive delisting of the parallel Hatch-Waxman claims. Teva Branded Pharm. Prods. R&D, Inc. v. Deva Holding AS, Case No. 2:24-cv-04404 (D.N.J. Aug. 28, 2024).

Even if the litigation is not dismissed, delisting raises a substantial remedies question. A patentee prevailing on a Hatch-Waxman infringement claim is statutorily entitled to an order preventing final FDA approval until after the patent expires. This remedy is unique to patents listed in the Orange Book. After delisting, a patentee prevailing on any other infringement claim cannot obtain a permanent injunction unless the situation satisfies the equitable test under eBay Inc. v. MercExchange, L.L.C., 547 U.S. 388 (2006). Delisting also raises a substantial question about the kinds of evidence that may be required to show infringement. In ANDA cases, if the controlling portion of the ANDA (the so-called “specification”) speaks directly to the factual infringement question, then infringement can essentially be decided on what the ANDA “says.” Sunovion Pharms., Inc. v. Teva Pharms. USA, Inc., 731 F.3d 1271, 1279 (Fed. Cir. 2013). The infringement inquiry only shifts to tests or observations of the physical ANDA product itself when the ANDA does not squarely answer the question of whether a claim limitation is met. Ferring B.V. v. Watson Lab’ys, Inc.-Fla., 764 F.3d 1382, 1387-88 (Fed. Cir. 2014). Delisting arguably makes Sunovion-type infringement arguments inapplicable, even if the litigation proceeds.

In a recent decision from the District of New Jersey, Rayner Surgical Inc. v. Somerset Therapeutics, LLC, the court denied a defense motion for judgment on the pleadings in a Hatch-Waxman patent infringement action that involves OMIDRIA®, a combination pharmaceutical product containing ketorolac, phenylephrine, and a buffer system used during cataract surgery. The court found genuine factual disputes on both literal infringement and the doctrine of equivalents, reinforcing the high bar for dispositive relief at the pleadings stage in ANDA litigation.

The central dispute turned on the court’s claim construction of the term “phenylephrine, ketorolac, and a buffer system,” which the court had construed to mean “a formulation with at least three separate components: (1) phenylephrine, (2) ketorolac, and (3) a buffer system.” The defendant argued that because its product does not contain a buffer system that is separate and distinct from the active pharmaceutical ingredients, the plaintiffs’ allegations of both literal infringement and infringement under the doctrine of equivalents fail as a matter of law. The plaintiffs countered that factual questions remained as to whether components in the defendant’s product satisfy the construed claim limitations.

The court first rejected the defendant’s argument that the complaint was deficient for relying on “unsupported allegations.” Citing established precedent, the court recognized that Hatch-Waxman plaintiffs are afforded a relaxed pleading standard because essential information about the ANDA product’s formulation lies uniquely within the defendant’s control. The court held that the plaintiffs had sufficiently pled their claims by alleging their “interest in the asserted patents, the filing of defendant’s ANDA, and [their] contentions that defendant’s product will infringe [those] patents.” On the question of literal infringement, the court declined to grant judgment on the pleadings, finding a genuine factual dispute as to whether the defendant’s product contains a separate and distinct buffer system. On the doctrine of equivalents, the defendant argued that tromethamine, introduced via ketorolac tromethamine, could not serve as an equivalent of a separately added buffer system while also meeting the ketorolac limitation. The court agreed with the plaintiffs that this inquiry is inherently fact-intensive and cannot be resolved on a motion for judgment on the pleadings.

In an ANDA litigation, the District of Delaware recently denied the plaintiffs’ motion to strike portions of the defendants’ expert reports and related deposition testimony. Although the defendants’ invalidity contentions did not state the specific theories of invalidity upon which the expert opined, the court found that none of the Pennypack factors supported excluding that expert testimony. During discovery, the defendants served final invalidity contentions followed three months later by an opening expert report on invalidity. The expert opined that certain asserted claims were invalid for lack of written description and lack of enablement even though those theories were not disclosed in the contentions. The plaintiffs did not object to these portions of the expert’s report, nor did they seek discovery to rebut the untimely theories. Instead, the plaintiffs served a rebuttal report addressing the substance of the opinions, and, after the expert had served a reply report, took extensive deposition testimony of the expert on the opinions. Thereafter, the plaintiffs moved to strike the portions of the expert reports and deposition testimony relating to written description and enablement as untimely.

The court agreed that the opinions were untimely, but explained that the plaintiffs had missed the opportunity to object through their “subsequent course of conduct,” which included the strategic choice of challenging the substance of the untimely opinions. Applying the Pennypack factors — surprise or prejudice, ability to cure, disruption of trial, bad faith or willfulness, and importance of the evidence — the court found that each factor weighed against exclusion. The plaintiffs had failed to show prejudice because they chose to substantively challenge the opinions in a rebuttal report; they could not show surprise six months after the opinions had been disclosed; they failed to articulate what additional discovery was needed; there was no evidence of bad faith; and they had undercut their own argument that the evidence was unimportant by devoting significant resources to the issue. The court denied the motion. Harmony Biosciences, LLC v. Lupin Ltd., Civil Action No. 23-1286-JLH-SRF (D. Del. Dec. 12, 2025).