The Algorithmic Antitrust Divide: Third Circuit's Atlantic City Casino Ruling Creates Circuit Split on AI Price-Fixing Claims

The Algorithmic Antitrust Divide: Third Circuit's Atlantic City Casino Ruling Creates Circuit Split on AI Price-Fixing Claims

The Third Circuit has thrown down the gauntlet in the emerging battle over algorithmic price-fixing, reviving an antitrust class action against Atlantic City casino operators that alleges they used AI-powered software to coordinate room rates. The decision, which directly contradicts a 2025 Ninth Circuit ruling dismissing similar claims against Nevada casinos, creates a circuit split that could reshape how courts evaluate antitrust liability when pricing decisions flow from shared algorithms rather than smoke-filled rooms.

According to Reuters, the Third Circuit held that the plaintiffs' claims were sufficient to proceed under federal antitrust law, finding that allegations of AI-driven price coordination among Atlantic City casino operators stated a viable claim. The ruling breathes new life into a theory that has bedeviled antitrust practitioners: when does the use of common pricing software cross the line from parallel conduct into an unlawful agreement under Section 1 of the Sherman Act?

The Pleading Problem: Parallel Conduct vs. Concerted Action

The fundamental challenge in algorithmic pricing cases lies in Bell Atlantic Corp. v. Twombly, 550 U.S. 544 (2007), which requires plaintiffs to plead facts suggesting an actual agreement, not merely parallel behavior. When multiple competitors independently adopt the same pricing algorithm, have they "agreed" to fix prices, or are they simply making rational, independent business decisions?

The Third Circuit's willingness to let these claims proceed suggests the court found something more than mere parallel adoption. The allegations likely included facts about information sharing, coordinated implementation, or communications among the casino operators that pushed the case beyond Twombly's threshold. This matters enormously for practitioners because it signals that courts in the Third Circuit will scrutinize the context surrounding algorithm adoption, not just the algorithm itself.

The Ninth Circuit's contrary ruling in the Nevada casino case took a more restrictive view, apparently finding that the use of AI pricing software, without more, doesn't establish the requisite agreement. This divergence creates immediate strategic considerations for both plaintiffs and defendants in algorithmic pricing cases.

Forum Shopping Returns to Antitrust

The circuit split virtually guarantees forum shopping in future algorithmic pricing cases. Plaintiffs' counsel will gravitate toward the Third Circuit's more permissive standard, while defendants will seek to establish venue in the Ninth Circuit. Expect to see increased motion practice on venue and transfer issues under 28 U.S.C. § 1404(a), as parties jockey for favorable precedent.

More significantly, the split increases the likelihood of Supreme Court review. The Court has shown renewed interest in antitrust issues in recent terms, and a clear circuit conflict on an emerging technology issue presents an attractive certiorari candidate. In the meantime, the uncertainty creates both risk and opportunity.

What This Means for AI Vendors and Their Customers

The ruling should send shockwaves through the growing industry of AI-powered pricing optimization. Companies that license pricing algorithms to multiple competitors in the same market now face increased litigation risk, at least in the Third Circuit. The decision suggests that courts may look skeptically at arrangements where competitors share pricing data or decision-making authority with a common vendor.

For in-house counsel, the message is clear: the mere fact that "the algorithm did it" won't insulate your company from antitrust liability. Businesses using AI pricing tools need to implement safeguards to ensure they're not inadvertently participating in coordinated pricing schemes. This includes:

• Avoiding the sharing of competitively sensitive information with pricing software vendors who also serve competitors
• Maintaining independent decision-making authority over final pricing decisions
• Documenting the independent business justifications for adopting algorithmic pricing tools
• Implementing firewalls between pricing data and other competitively sensitive information

The Class Certification Battle Ahead

While the Third Circuit's ruling allows the case to proceed past the pleading stage, the real battle will come at class certification under Federal Rule of Civil Procedure 23(b)(3). The plaintiffs will need to demonstrate that common questions predominate over individual ones, including proof of antitrust impact and damages on a classwide basis.

Algorithmic pricing cases present unique challenges at certification. If different class members were affected differently by the alleged coordination—some paying more, some less, depending on booking patterns and timing—the defendants will argue that individual issues predominate. The plaintiffs' ability to present a coherent damages model under Comcast Corp. v. Behrend, 569 U.S. 27 (2013), will be critical.

The Broader Implications

This decision arrives at a pivotal moment for AI regulation. As businesses increasingly rely on algorithmic decision-making, courts are grappling with how traditional legal frameworks apply to machine-mediated conduct. The Third Circuit's ruling suggests that at least some courts will hold companies accountable for the foreseeable consequences of delegating pricing decisions to AI systems.

The split also highlights the need for clearer guidance on when the use of shared technology crosses into anticompetitive territory. Until the Supreme Court weighs in or Congress acts, businesses operating in multiple circuits face a patchwork of standards that could make compliance planning a nightmare.

For antitrust practitioners, the message is unmistakable: algorithmic pricing cases are here to stay, and the circuit split creates both peril and opportunity. Plaintiffs' attorneys now have a roadmap for pleading viable claims in favorable jurisdictions, while defense counsel must prepare for increased scrutiny of their clients' AI pricing practices. The age of "the algorithm made me do it" as a defense may be coming to an end—at least in the Third Circuit.