Highly Anticipated First Circuit Opinion on AKS Causation in FCA Cases Brings Hope for Defendants – But Also Muddies the Waters
Client Alert | February 20, 2025
On February 18, 2025, the First Circuit handed down a much-anticipated decision on the causation element of False Claims Act (FCA) cases premised on the Anti-Kickback Statute (AKS), as amended by the Affordable Care Act in 2010. See United States v. Regeneron Pharms., Inc., No. 23-2086, slip op. (1st Cir. Feb. 18, 2025).
Summary
Since 2010, the Anti-Kickback Statute has provided that claim for government payment “resulting from” an AKS violation is automatically false or fraudulent for purposes of the FCA. The U.S. Department of Justice historically has interpreted this provision exceptionally broadly, often taking the position that a kickback inherently “taints” every claim submitted after a kickback is payment, regardless of whether the provider would have prescribed or recommended an item or service even without the kickback. That is, DOJ’s view has been that it should not have to prove a claim was actually caused by a kickback at all.
The First Circuit, however, joined the Sixth and Eighth Circuits—and deepened a split with the Third Circuit—in holding that, to prove that a claim “result[s] from” an AKS violation, the government (or a qui tam relator) must prove that the claim would not have been submitted but for the AKS violation. The First Circuit rejected less onerous causation standards advanced by the government and adopted by the Third Circuit—including variations of DOJ’s so-called “taint” theory of AKS-based FCA liability. But the First Circuit’s opinion simultaneously muddied the waters, as it observed that the AKS’s “resulting from” provision is just one “pathway” to FCA liability from an AKS violation, and that FCA plaintiffs could pursue a different “pathway”—not before the Court on appeal—based on alleged materially false certifications of AKS compliance to government health programs.
The Regeneron Decision
Regeneron Pharmaceuticals manufactures, markets, and sells the drug Eylea, a treatment for wet age-related macular degeneration (AMD). The drug is reimbursed under Medicare Part B, which requires patients to pay 20% of the drug’s cost as a co-pay. The government accused Regeneron of violating the AKS by indirectly paying the copayments for Medicare patients who took the drug. According to the government, the price of the drug—more than $1,800 per injection—meant that patients often faced annual out-of-pocket costs exceeding $2,000, which discouraged them from using the drug.
To alleviate this financial burden, Regeneron allegedly donated more than $60 million to the Chronic Disease Fund (CDF), a charitable foundation that provides copayment assistance. The government alleged that these donations comprised kickbacks intended to induce doctors to prescribe Eylea (and patients to maintain their prescriptions), thereby increasing Medicare reimbursement claims. The government argued that, because these payments violated the AKS, any Medicare claim for Eylea prescribed to a patient who received this co-pay assistance should be considered false or fraudulent under the FCA.
In litigation with DOJ, Regeneron argued that its co-pay assistance did not directly cause doctors to prescribe Eylea and that a Medicare claim should only be false under the FCA if the kickback was the but-for cause of the claim. In other words, if a doctor would have prescribed Eylea and submitted a Medicare claim even without the co-pay assistance, then the claim could not have “resulted from” an AKS violation. The district court sided with this argument, granted Regeneron’s motion to dismiss DOJ’s complaint, and then agreed to certify the issue for interlocutory review.
On appeal, the First Circuit focused on the phrase “resulting from” in the text of the AKS, which (as amended in 2010) states that “a claim that includes items or services resulting from a violation of [the AKS] constitutes a false or fraudulent claim” under the FCA. 42 U.S.C. § 1320a-7b(g) (emphasis added).
The First Circuit held that the “resulting from” phrase imposes a but-for causation standard. This means that for a claim to be considered false under the FCA due to an AKS violation, the government (or a qui tam relator) must prove that the kickback was the “actual cause” of the claim being submitted. The court relied on Supreme Court precedent (e.g., Burrage v. United States, 571 U.S. 204 (2014) and Paroline v. United States, 572 U.S. 434 (2014)) which generally interpreted similar causation language as requiring proof that the event in question would not have occurred but for the preceding act. The First Circuit found no textual or contextual reasons to deviate from this default causal standard. Notably, the First Circuit rejected the government’s argument that, for example, the legislative history and purpose of the AKS require a broader construction of the phrase “resulting from” (i.e., an interpretation that would allow liability even when the claim would have been submitted regardless of the kickback).
But the First Circuit also indicated that a false-certification theory can provide a separate pathway to proving FCA liability based on alleged kickbacks—and has a different causation standard. Before Congress amended the AKS in 2010, courts recognized that FCA liability could attach to AKS violations under a false-certification theory if compliance with the AKS was material to the government’s decision to pay a claim. On appeal, the government argued that Congress enacted the 2010 amendment to supplement, not replace, false-certification case law. The First Circuit agreed, holding that false certification remains a valid theory of FCA liability even after the amendment. The court explained that theory requires proof that the provider falsely represented compliance with the AKS and that the misrepresentation could have influenced the government’s decision to pay a claim (i.e., was material to the payment), but does not require proof that the AKS violation was a but-for cause of the submission of the claim.
Other Relevant Jurisprudence
In reaching this result, the First Circuit joins the Sixth and Eighth Circuits in holding that “resulting from” requires but-for causation. See United States ex rel. Martin v. Hathaway, 63 F.4th 1043 (6th Cir. 2023); United States ex rel. Cairns v. D.S. Med. LLC, 42 F.4th 828 (8th Cir. 2022). In those cases, the Sixth and Eighth Circuits had held that the government or a relator must show that, but for the AKS violation, the false claim would not have been submitted to a federal healthcare program.
In so holding, those circuits rejected the Third Circuit’s less stringent approach from United States ex rel. Greenfield v. Medco Health Sols., Inc., 880 F.3d 89 (3d Cir. 2018). In Greenfield, the Third Circuit held that an AKS violation can trigger FCA liability even if there is no proof that the kickback directly caused the claim as long as a patient has been exposed to an illegal inducement before a claim is submitted.
Potential Ramifications
Although the First Circuit provided much-needed clarity on the “resulting from” language in the AKS, its analysis of the certification issue may cause the government or relators to attempt an end run around the as-amended AKS and revert to the no-causation “taint theory” of liability. Meanwhile, Supreme Court review of the AKS causation question feels inevitable—there is a circuit split; the Court has taken up an FCA-related case in most terms in recent memory; and the Court has previously agreed to take up cases like Burrage and Paroline. But given the Regeneron court’s apparent invitation to a different “pathway” to AKS-based FCA claims, plaintiffs may feel less need to press the issue in petitions for certiorari.
In the meantime, we expect to see:
- Efforts by the defense bar to persuade other circuit courts to side with the First, Sixth, and Eighth Circuits;
- Scrutiny at the pleading stage as to whether the government or relators have adequately pleaded a causal connection between alleged AKS violations and false claims;
- Litigation in other circuits about whether the certification “pathway” remains open after Congress amended the AKS to link it to the FCA;
- Additional arguments by defendants regarding the various factors that contribute to a healthcare provider’s decision-making (e.g., analysis of clinical treatment guidelines, Department of Health and Human Services expert panel recommendations, clinical treatment patterns, and/or medical association guidance, prior efficacious use of a particular therapy, etc.);
- Increased use of statistical experts to try to demonstrate (or rebut) but-for causation; and
- Arguments focused on DOJ’s historical position that the measure of damages in AKS matters is the full value of the paid claim.
Open questions about the scope of liability in AKS-based FCA cases still abound after Regeneron. The Supreme Court has been clear in recent years that it believes the elements of common law fraud should be read into the FCA—elements that presumably include causation. Thus, it stands to reason that even certification theories require proof of causation—and we expect that defendants will retrench and advance causation-, falsity-, and materiality-focused arguments even under those theories.
Moreover, none of the cases interpreting the AKS’s causation requirement have taken head-on the question of what the government’s damages should be in a civil FCA case based on alleged AKS violations. The FCA imposes liability only on those damages “sustained by” the government. While the government’s position in AKS cases is that its damages are 100% of the claim amount—even where the item or service claimed for reimbursement was medically necessary and actually provided—that position does not square with common law principles of fraud damages or federal courts’ analysis of damages in other types of FCA cases. Regardless of how the AKS causation question is ultimately answered in the coming months and years, we may well see a new wave of cases focused on this damages question.
Gibson Dunn lawyers regularly counsel clients on the False Claims Act issues and are available to assist in addressing any questions you may have regarding these issues. Please contact the Gibson Dunn lawyer with whom you usually work, the authors, or any leader or member of the firm’s False Claims Act/Qui Tam Defense practice group:
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