NFL asks US Supreme Court to hear Kalshi case as prediction market integrity fight intensifies

The NFL has filed an amicus brief with the US Supreme Court, urging it to take up Flaherty v. KalshiEx, LLC, a case that could settle the dispute over the future of sports event contracts. The 32-page filing was co-authored by former US Attorney General William Barr. The league argued that review is needed to protect the integrity of professional sports events and the participants in these markets.

The NFL said clarity on sports prediction markets is essential for sports integrity and consumer protection. It claimed that the Commodity Futures Trading Commission, which maintains that it holds exclusive jurisdiction over such derivatives, and various operators have resisted its requests to implement appropriate safeguards. The league repeated objections it raised earlier in a filing during the CFTC's comment period, singling out contracts on whether a kicker will miss a field goal, the next penalty in a game, and phrases mentioned during a broadcast. It wrote that it is at best unclear whether the commission has the framework, oversight capacity and enforcement resources to protect game integrity.

Kalshi and Polymarket both said they treat integrity as a priority. Polymarket said it shares the NFL's commitment and is constantly enhancing its market surveillance tools. Kalshi said it is actively policing sports-related markets and had tried to work constructively with the league. NBA Commissioner Adam Silver, speaking to CNBC in Macau, acknowledged integrity and data-capture issues in prediction markets and said he prefers a federal standard, unlike the NFL, which favours state regulation.

Integrity was also the focus at the Predict 2026 conference in Manhattan. Coalition for Prediction Markets President Sean Patrick Maloney took part in a panel on combating insider trading, and said a strict sentence would be appropriate if classified information was misused. The discussion referenced the case of Gannon Van Dyke, a US Army special forces soldier indicted in April over Polymarket trades on whether Venezuelan President Nicolas Maduro would be removed from office. Prosecutors say he staked about $33,000 and made roughly $400,000. He has pleaded not guilty.

In a separate development, the Seminole Tribe of Florida filed a 72-page complaint in Broward County against DraftKings and its CEO Jason Robins. The tribe alleges DraftKings is conducting illegal sports betting in Florida in violation of its 2021 gaming compact, and objected in particular to the operator's Super App, which combines multiple verticals in one platform.