The U.S. Supreme Court may soon be asked to clarify how far federal regulators can go in policing prediction markets—after the National Football League (NFL) filed an amicus brief backing New Jersey’s effort to get the justices to review a case involving Kalshi.

In the brief submitted on Wednesday, the NFL urged the Supreme Court to grant certiorari to New Jersey Attorney General Jennifer Davenport and Mary Jo Flaherty, the state’s gaming enforcement interim director. The dispute centers on whether prediction market event contracts fall within federal oversight—particularly under the Commodity Futures Trading Commission (CFTC)—or whether states retain primary regulatory authority.

Key takeaways

The NFL supported New Jersey’s request for Supreme Court review of the Kalshi litigation, arguing the issue impacts sports-event integrity and consumer protection.
The NFL contends many event contracts are “highly susceptible to manipulation” and therefore pose special risks to game integrity.
The league argues that, from the NFL’s perspective, the CFTC has not provided “sensible safeguards” for these types of contracts.
New Jersey and 39 other states say an unresolved federal–state regulatory conflict has created a “national turf war” that only the Supreme Court can settle.
As of Thursday, the Supreme Court had not indicated whether it would take up the case; Kalshi has until Nov. 9 to respond.

The NFL’s position in the Supreme Court filing

The NFL’s amicus brief was filed in response to New Jersey officials’ petition asking the Supreme Court to consider the proper jurisdiction for prediction market companies. The NFL’s participation is notable because it ties a legal question about regulatory authority directly to potential sports outcomes.

According to the brief, the case should be reviewed partly because contracts involving sporting events—such as those traded on Kalshi and other platforms—may be labeled or structured in a way that raises concerns about whether they should be treated as “swaps.” The NFL also argued the dispute warrants Supreme Court attention to help “preserve game integrity” and “protect customers.”

In support of its concerns, the NFL cited volume data it says shows prediction markets remain heavily connected to the league’s games. The filing states that during the first Sunday of the football season, “more than half of all prediction-markets’ trading volume” (about $1.8 billion out of $3.3 billion) related to the NFL.

The NFL went further than data and characterization, arguing that many event contracts could be manipulated by a small number of actors if they know relevant details in advance. The brief asserts the greatest threats arise from contracts tied to outcomes that could be affected by participants and decision-makers, including players, coaches, or officials.

As the NFL put it in the brief, these bets “pose the greatest threats to game integrity” because “many can be manipulated by a single person,” especially if the relevant information is known in advance—for instance, a player can alter performance, a coach can change a lineup, or an official can make (or not make) certain calls.

Why New Jersey says federal and state roles are in conflict

New Jersey’s underlying case is directed at how the federal government and states regulate prediction markets. The state argues there is a conflict between the CFTC’s approach and state authority, which it says has contributed to inconsistent outcomes and uncertainty for regulators, platforms, and market participants.

On Wednesday, 39 states and the District of Columbia also filed an amicus brief supporting New Jersey. That filing characterizes the dispute as a “national turf war” and argues that it cannot be resolved without Supreme Court guidance.

In their submission, the states warn that delay could allow the federal-state clash to intensify. They argue the situation produces unpredictability about which law applies and to whom, and they urge the Court to step in to resolve what they describe as a split—so that lower courts receive clear direction on the question presented.

Kalshi, for its part, has previously argued against a patchwork regulatory regime. After New Jersey’s petition was filed in September, Kalshi spokesperson Dani Lever told Cointelegraph that the company could not be “regulated by 50 different regulators.” Earlier coverage from Cointelegraph noted the broader stakes of whether prediction markets are treated as regulated federal instruments or as state-governed gambling-like activity.

Federalizing sports-bets oversight is a “major question,” NFL argues

Another central thread in the NFL’s filing is the scope of federal authority—especially whether sports betting should be handled through federal regulation rather than state-by-state frameworks.

The NFL argued that the Supreme Court should consider whether federalizing the regulation of sports betting is a “major question” and suggested the CFTC has not provided an adequate framework to mitigate the risks the league says are inherent to certain event contracts.

The filing also highlights what it characterizes as insufficient consumer protections for these products. The NFL argues that, for the types of event contracts at issue, the regulatory system lacks what the league calls “sensible safeguards” under the CFTC.

While the NFL’s brief is not itself a merits decision, it reinforces the argument that the legal classification of prediction market contracts could carry real-world consequences beyond courtroom definitions—particularly for leagues and the integrity of competitions.

What happens next as the Court considers whether to take the case

As of Thursday, the Supreme Court had not announced whether it would grant review of the petition. The next procedural milestone is on Kalshi’s side: the company received an extension to respond to New Jersey’s filing and has until Nov. 9 to address issues including jurisdiction, manipulable event contracts, and consumer protection.

Even if the Supreme Court ultimately declines to take the case, the broader debate over prediction markets is unlikely to stop. The conflict between federal and state approaches has already spawned multiple actions and challenges, and new appeals could keep coming as courts grapple with whether CFTC authority reaches the kinds of contracts traded on prediction platforms.

For investors, builders, and market participants, the most important thing to watch is whether the Supreme Court signals interest in resolving the regulatory turf question; that decision will shape how quickly platforms can anticipate consistent compliance expectations—and how leagues and states continue to frame risks tied to event-contract trading.