[Digital Today reporter Chi-gyu Hwang] The National Football League (NFL) has sided with a state government in a legal battle over prediction markets. The NFL backed New Jersey, which is suing prediction market operator Kalshi, and filed an amicus brief asking the U.S. Supreme Court to take up the case. An amicus brief is a filing by a third party, not a litigant, offering views for the court to consider.

The NFL has in effect supported New Jersey's argument that the federal Commodity Exchange Act does not prevent states from regulating sports contracts as gambling.

According to a recent report by Bankruss, the NFL argued that sports contracts are gambling and that allowing prediction markets to sell them outside state gambling laws undermines game integrity and consumer protection.

In a filing submitted by the NFL, $1.8 billion of $3.3 billion in prediction market trading volume on the first Sunday of the season's opening weekend was concentrated on NFL games. That was more than half of the day's trading.

The NFL has raised issues with prediction markets in recent months, and this time stepped up the pressure.

In March, the NFL sent a letter to companies that run prediction markets asking them to ban contracts vulnerable to manipulation, such as player injuries, referee decisions and individual plays that a single person can influence. In May, it called on the Commodity Futures Trading Commission (CFTC) to strengthen safeguards. In July, it said a proposed CFTC rule fell short of protections applied to existing sports betting operators. In September, it said contracts it had flagged were still being traded.

Even so, the NFL appears to be keeping the door open to talks. Front Office Sports reported that the NFL discussed cooperation with Kalshi, Polymarket and the CFTC for several months, but no partnership was reached before the season began. NFL Commissioner Roger Goodell (로저 구델) also confirmed in a CNBC interview released on Sept. 11 that it was talking with operators about partnerships.

The NFL has cited regulatory gaps and legal uncertainty as reasons for delaying contracts. The details of private discussions are not known, but Bankruss reported that if a partnership is reached, the NFL could be more directly involved in monitoring market integrity and could also secure licensing, data and marketing deals.

U.S. appeals courts have split on whether state governments can regulate prediction markets. The 3rd Circuit Court of Appeals sided with Kalshi, while the 6th and 9th Circuits sided with the other side. The Supreme Court has not decided whether to take the case.

Sports organizations also differ in how they calculate their positions on prediction markets.

The NHL partnered with Kalshi and Polymarket in October last year, and the UFC and MLS signed deals with Polymarket. MLB also joined hands with Polymarket in March and separately signed an agreement with the CFTC to strengthen market integrity. The NFL renewed deals with DraftKings and FanDuel and added Fanatics in August, choosing existing sports betting operators.

DraftKings, FanDuel and Fanatics also run prediction market businesses. The NFL is trying to block prediction markets, but its partners are making money from them.

The NBA's moves on prediction markets are also drawing attention.

With the season set to open on the 20th, the NBA is reported to have circulated partnership proposals in September to Kalshi, Polymarket and Fanatics. But the NBA urged stronger oversight of prediction markets in May last year, and in July this year argued that a proposed CFTC rule was insufficient to prevent insider trading and market manipulation. Even so, it said in April it would not state a position on whether prediction markets are legally gambling.

Bankruss forecast that if the NBA reaches a partnership, the NFL would remain an exception among major leagues, but if talks break down the NBA could also side with state governments. The analysis said that if the two leagues stand together, their voice could strengthen against Kalshi's argument that federal law takes precedence over state gambling laws, and pressure could grow to demand Supreme Court review.