The National Football League (NFL) filed a brief with the U.S. Supreme Court, arguing that states should be able to regulate sports-related contracts offered by prediction-market platform Kalshi. The NFL said that trading in prediction markets tied to its games reached $1.8 billion on the first Sunday of a single season, emphasizing that “effectively sports betting” on this scale cannot be left solely to the federal Commodity Futures Trading Commission (CFTC).
Key points
The NFL filed a brief supporting New Jersey regulators’ petition asking the Supreme Court to hear their case against Kalshi.
Of the $3.3 billion in total prediction-market trading on the first Sunday of the season, $1.8 billion was reportedly tied to NFL games.
Kalshi must file its response by November 9, and it remains unclear whether the Supreme Court will formally agree to hear the case.
NFL joins Supreme Court case against Kalshi
The NFL filed a brief with the Supreme Court on Thursday in *Flaherty v. KalshiEX*. The case stems from an appeal by New Jersey gaming regulators after they lost a lawsuit against Kalshi in the Third Circuit in April. The NFL estimated that prediction markets saw $3.3 billion in total trading volume on the first Sunday of the season, with $1.8 billion tied to NFL game outcomes.
The NFL said the CFTC had not adopted the league’s list of “types of bets that should be prohibited.” It particularly objected to contracts on specific events—such as individual plays, calls, or missed kicks—that individuals like players, coaches, and referees could directly influence.
The NFL also noted that CFTC rules allow people to trade from age 18, while the minimum age for sports betting in most states is 21. It questioned the CFTC’s capacity to oversee a nationwide market, noting that the agency has only 543 staff members.
The NFL urged the Supreme Court to act “before another season passes by.”
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Kalshi and CFTC push back
Kalshi spokesperson **Elisabeth Diana** said the company had held several discussions with the NFL to ensure market integrity but “received no response.” She added that every other league had agreed to share data and cooperate.
The CFTC countered that it had been “in continuous communication from day one” with the NFL during the rulemaking process. It also called the NFL’s decision not to sign a formal cooperation agreement with the CFTC “regrettable.”
Gaming attorney **Daniel Wallach** wrote on X (formerly Twitter) that the NFL’s brief “meaningfully increases” the likelihood that the Supreme Court will grant certiorari in the case.
**Gary Gensler**, who chaired the CFTC when the Dodd-Frank Act was implemented, and former Senator Chris Dodd, who introduced the legislation, also filed briefs with the court. They argued that Congress never intended to transfer authority over sports betting regulation from state governments to the CFTC.
Prediction markets at the crossroads of federal and state law
The question is whether contracts based on sporting events qualify as “swaps” under the Commodity Exchange Act. If they do, those contracts fall exclusively under the CFTC’s jurisdiction and are not subject to state gambling laws.
The Third Circuit ruled in Kalshi’s favor on April 6, but the Ninth Circuit and the Sixth Circuit ruled against Kalshi on September 28 and September 25, respectively. With the federal appeals courts split, New Jersey has joined 39 states and the District of Columbia in presenting a united position, and Kalshi must file its formal response with the Supreme Court by November 9.
Well before filing its brief, the NFL sent letters to Kalshi and **Polymarket** in March, demanding that they stop listing contracts tied to individual plays and player injuries. In May, it sent the CFTC a list of contracts on specific events, such as missed kicks and officiating calls, that it wanted banned. Then, in July, it criticized the CFTC’s proposed rules as still “significantly inadequate.”
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