According to CNBC, the National Football League is asking the Supreme Court to rule that states should keep control over sports betting as part of its fight over prediction markets regulation. In an amicus brief backing New Jersey regulators in their case against Kalshi, the league argued that sports prediction contracts amount to gambling rather than financial swaps that should be regulated only by the federal government. The NFL said football accounted for $1.8 billion in prediction markets trading on the first Sunday of the season, more than half of total volume, and said it wants a minimum betting age of 21, while Kalshi allows customers as young as 18. The league also said it is concerned about contracts tied to outcomes that could be manipulated, including field goals, injuries and officiating. Commissioner Roger Goodell said in an interview with CNBC Sport on September 10 in Australia that the league wants stronger protections before considering a partnership with the new markets.