At least 10 groups representing tribal gaming interests have sent letters to the Commodity Futures Trading Commission (CFTC) calling the emergence of sports event contracts an illegal circumvention of state gambling laws.

Among the groups are the Arizona Indian Gaming Association, California Nations Indian Gaming Association, Indian Gaming Association, Tribal Alliance of Sovereign Indian Nations and Yuhaaviatam of San Manuel Nation. They all contacted the CFTC between Feb. 10 and Feb. 22 to express concern about sports futures trading, according to agency records.

The memos went out as part of the CFTC’s 45-day public comment period on the prediction markets, which will be followed by an in-person roundtable in Washington D.C. at CFTC headquarters late next month to determine agency policy.

Financial technology companies Kalshi and Crypto.com continue to offer binary contracts on the results of sports events in all 50 states despite sports betting industry opposition. Kalshi and Crypto.com facilitated millions of dollars of trades before (and during) the Super Bowl earlier this month. Their platforms are currently overseen by the CFTC rather than states because they have not been legally classified as gambling products.

While there are signs the CFTC might settle on a permissive approach to sports futures—President Donald Trump nominated Kalshi board member Brian Quintenz to lead the agency—the blowback from tribal groups ahead of the roundtable could portend a long-term legal fight.

Kalshi and Crypto.com have denied they are violating any state or federal law. Trump, whose son Donald Trump Jr. is an advisor to Kalshi, has a long history of clashing with tribes over their casino rights.

The letters from Native American advocacy groups asking the CFTC to prohibit sports contracts represent the first record of tribal opposition to sports futures trading. They echo many of the concerns recently outlined by the American Gaming Association, a trade group representing nationwide gaming interests.

Tribes are highly protective of their exclusive rights to offer gambling products in states where such action is not otherwise permitted. Those states include the two most populated—California and Texas. The groups allege sports event futures amount to gambling and should be subject to the same laws and limitations as sportsbook operators such as FanDuel and DraftKings.

“The IGA strongly urges the CFTC to make it clear that sports contracts are prohibited from being listed or made available for clearing or trading,” wrote the Indian Gaming Association, which represents 124 tribes around the U.S.

“Trading of sports contracts is gaming, violates state and federal law and is contrary to public policy for various reasons. Importantly, allowing sports contracts to be listed and traded will interfere with the sovereign right of tribes and states to exercise their police power to regulate gaming within their respective territories—a right long recognized by courts throughout the United States.”

Additionally, location verification service GeoComply sent a letter to the CFTC requesting the agency establish “a clear distinction between federally regulated financial products and state-regulated betting products.”

GeoComply’s business model depends on location restrictions in gambling, so allowing a ubiquitous substitute for tightly regulated sports betting could hurt revenue.