Amarin v. Hikma: Supreme Court Applies Twombly, Iqbal and Leaves Induced-Infringement Standards Untouched

The US Supreme Court’s recent decision in Hikma Pharmaceuticals USA Inc. v. Amarin Pharma Inc. clarifies what federal pleading standards demand in induced-infringement cases involving pharmaceutical “skinny” labels and off-label infringement theories. The ruling holds that patent holders must include allegations of “active” encouragement—whether explicit or implicit—to state a claim. This decision affects litigation strategies and clarifies the availability of the skinny label pathway, which has long been an important consideration for branded and generic pharmaceutical companies.

KEY TAKEAWAYS

• The Supreme Court held that, to plead a claim of induced infringement based on a generic competitor’s skinny label, a brand manufacturer must allege that the generic competitor actively encouraged infringing uses, not just that doctors could plausibly read alleged statements as instructions to infringe.
• The decision narrows the circumstances under which off-label, induced-infringement claims based on a US Food and Drug Administration (FDA)-approved generic drug skinny label may survive a motion to dismiss and underscores the need for branded companies to provide concrete evidence of purposeful encouragement—statements designed to encourage infringement, not those that merely could encourage infringement.
• Implicit or explicit encouragement can support inducement liability, but mere omissions, industry-standard descriptions, or vague statements akin to those Hikma made do not suffice.

In 2012, Amarin Pharma Inc. obtained FDA approval for Vascepa (icosapent ethyl) in treating severe hypertriglyceridemia (the SH indication). Generic manufacturer Hikma Pharmaceuticals USA Inc. later filed an abbreviated new drug application (ANDA) for generic icosapent ethyl in connection with the SH indication. By 2019, FDA had approved Amarin’s Vascepa for a second, more common indication: reducing cardiovascular risk in hypertriglyceridemia patients who already take statins (the CV indication). Under the Hatch-Waxman framework, generic drug applicants may seek approval for fewer than all the approved uses of a branded drug by submitting what is known as a “section (viii) statement” in their ANDA, along with proposed labeling that omits corresponding uses of the drug.

This narrower labeling is colloquially called a “skinny label.” Once a district court invalidated Amarin’s SH-indication patents, Hikma supplemented its ANDA with a section viii statement, seeking approval of a skinny label that included only the SH indication and carved out Vascepa’s still-patented CV-indication.

Amarin then filed the lawsuit at issue, alleging that Hikma’s skinny label, in combination with Hikma’s website and other statements, induced infringement of its CV-related patent. According to Amarin, Hikma’s statements referenced Vascepa’s generic equivalence and therapeutic benefits in a way that encouraged using the generic for the carved-out CV indication, particularly given the lack of any statement by Hikma expressly stating its generic was approved for only the SH indication.

The district court dismissed Amarin’s complaint, finding the allegations did not plausibly show Hikma took affirmative steps to induce infringement. The US Court of Appeals for the Federal Circuit reversed, reasoning that, although the skinny label itself did not encourage off-label use, the combination of the label with the various Hikma statements Amarin’s complaint cited was sufficient to plausibly allege active inducement. The Supreme Court granted certiorari to review the sufficiency of the inducement allegations under the Twombly/Iqbal pleading standard.

THE SUPREME COURT’S DECISION

The Supreme Court unanimously reversed the Federal Circuit, holding that the allegations in Amarin’s complaint were insufficient to state a claim for induced infringement. In doing so, the Court did not adopt any new legal standards for induced infringement or pleading. Rather, it applied its “well-established federal pleading standards” from Twombly/Iqbal to the established third element of an induced infringement claim—whether the inducer took “active steps . . . to encourage direct infringement.”

The Supreme Court’s analysis focused on distinguishing allegations that merely make liability possible from those that make it plausible. The Court reiterated that when a complaint “pleads facts that are merely consistent with a defendant’s liability, it stops short of the line between possibility and plausibility of entitlement to relief.” Here, because induced infringement requires “active inducement,” the Court focused on whether the allegations rendered plausible that Hikma took “affirmative steps to encourage infringement.” It rejected the Federal Circuit’s “focus on whether the relevant statements could be read by medical providers as instructions to infringe,” noting that “the key question is whether a defendant actively encouraged infringement through its statements, not merely how others may understand those statements.”

With that focus in mind, the Supreme Court explained why Amarin’s particular allegations were deficient. It began by explaining how “several of the relevant statements” Hikma made had an “obvious alternative explanation” due to the “law and standard industry practice” surrounding generic drugs. First, the FDA requires generic manufacturers to ensure their skinny labeling matches approved uses and carves out patented indications. Hikma’s label, by design, therefore omitted the patented cardiovascular use to comply with FDA requirements.

The Court similarly noted how Hikma describing a generic product as an “AB-rated” equivalent (referencing FDA’s Orange Book rating typically granted to approved generic drugs) or a “generic” version of a brand-name drug were standard industry practices. Notably, an AB rating in the Orange Book may—and often does—trigger automatic substitution at the pharmacy-level dispensing stage under state laws, which do not typically consider the use for which a prescription may be written.

The Supreme Court characterized the remaining Amarin allegations as either “vague statements combined with speculation about how medical providers may act” or relying on “mere omissions, inactions, or nonfeasance.” The Court explained the latter were insufficient here because induced infringement “look[s] for affirmative ‘statements or actions’ precisely to avoid ‘trenching on regular commerce.’” Thus, Hikma’s statements describing the therapeutic category for its drug and the publication of sales figures (which Amarin attributed to sales for both SH and CV indications) did not give rise to a “plausible” claim that Hikma took active steps to induce infringement.

Though it found Amarin’s allegations insufficient here, the Supreme Court noted disagreement with Hikma’s argument “that active inducement must be ‘express.’” As the Court explained, “a defendant can achieve active inducement through implicit encouragement.” What ultimately matters is that, “implicit or explicit, the necessary inducement must be ‘clear’ to the relevant audience and ‘affirmative.’”

OBSERVATIONS AND FUTURE IMPLICATIONS

The Hikma decision is notable for what the Supreme Court did not do. The Court did not revise the induced infringement standard but instead engaged in a fact-specific application of the established Twombly/Iqbal pleading standard to the long-applied elements of induced infringement. Thus, while this decision provides guidance in pharmaceutical cases involving skinny labels, its broader applicability may be more limited than certain commentators initially suggested. There has been no fundamental shift to inducement law—simply a reiteration that inducement must be “active.”

This fact-specific application of Twombly/Iqbal to inducement claims will, of course, be most relevant in skinny label cases. The skinny label pathway—where generic drug applicants propose to omit certain approved uses of a drug—is often available when additional uses of a drug product are developed after the drug product’s initial approval.  By requiring brand drug manufacturers to plead affirmative acts of inducement, the decision alters Hatch-Waxman’s careful balancing of interests.

By rejecting the Federal Circuit’s greater willingness to draw plausibility inferences, the Supreme Court narrowed the circumstances in which off-label infringement theories are viable. For patent holders, the ruling confirms that complaints must include specific, plausible allegations of affirmative, purposeful conduct that explicitly or implicitly encourages infringement. Generalized claims based solely on standard labeling, generic equivalence statements, or speculation about third-party conduct will be more susceptible to motions to dismiss.

Still, the decision demonstrates that off-label infringement theories do, as a general matter, remain possible. The Supreme Court did not foreclose off-label induced infringement entirely and even rejected Hikma’s proposed “express” encouragement standard. While Hikma’s statements here were not enough to plausibly allege “active inducement,” other marketing of a skinny-labeled generic may well be sufficient, even if it only implicitly encourages infringement.

For companies marketing skinny-labeled generics, the decision provides clarity around the inferences that can and cannot be drawn from statutory labeling and industry-standard statements. In that sense, it clarifies the continued use of the section (viii) statement and skinny label pathway. But it does not obviate the need to carefully consider labeling, marketing, and external communications regarding generic drug products for clear, affirmative messages—whether explicit or implicit—that could be seen to encourage infringing uses.

Branded companies bringing inducement claims should focus on gathering concrete evidence of purposeful encouragement, particularly statements outside of skinny labels such as marketing and promotional materials, as the Supreme Court made clear that the content and context of instructions will be closely scrutinized.