Get 125% / $2,500 on 1st deposit!
New players only. Exclusive Welcome Bonus of up to $2,500
Sen. Richard Blumenthal has given every major US sports league a May 1 deadline to hand over details on gambling partnerships. Pressure now reaches beyond sportsbooks and into prediction markets as Washington takes a closer look at betting ties across sports.
Good to Know
Blumenthal sent letters to the commissioners of the NFL, NBA, MLB, NHL, MLS, and NCAA, demanding a full account of each group relationship with the gambling industry by May 1, 2026. Scope goes well beyond sportsbook sponsorships. He also wants data agreements, ad deals, prediction market partnerships, and any other commercial arrangement tied to wagering platforms.
“Since the federal ban on sports gambling, a ban supported by the leagues, was overturned eight years ago, gambling has permeated every aspect of the game,” he said in connection with the letters. “The consequences of this rampant rise of sports gambling have been accelerating addiction, threats to players, and even the corruption of the game.”
Since the Supreme Court ended the federal sports betting ban in 2018, leagues have built deeper business ties across betting, media, data, and fan engagement. Now Congress is asking for the paperwork.
Blumenthal has repeatedly gone after platforms such as Kalshi and Polymarket, arguing they try to offer sports wagering products while avoiding the state rules licensed sportsbooks face. His latest letters suggest he wants to map how deeply sports leagues now work with those companies.
Some of those ties are already public. MLB signed Polymarket as its Official Prediction Market in a deal worth up to $300 million over three years. The NHL has licensing deals with both Polymarket and Kalshi. MLS also has a marketing agreement with Polymarket. The NBA has not announced a prediction market deal, though Commissioner Adam Silver has said the league is examining the sector.
The NCAA stands apart from the pro leagues. It has opposed gambling partnerships and has pushed back hard against prop bets tied to college sports. NCAA leadership has also warned that sports event contracts on prediction platforms can threaten game integrity at the college level. Even so, Kalshi has listed college sports markets, including tournament games.
Blumenthal is framing disclosure as groundwork for broader federal gambling action. So, league responses may do more than answer a Senate letter. They could help shape the next fight over sports betting regulation, prediction markets, and what counts as gambling in the first place.
The NFL, NBA, MLB, NHL, MLS, and NCAA all received letters.
He wants a detailed breakdown of gambling industry relationships, including sportsbook deals, ad partnerships, data agreements, and prediction market ties.
Leagues must respond by May 1, 2026.
Blumenthal argues that platforms such as Kalshi and Polymarket try to offer sports wagering products while avoiding the rules that apply to licensed sportsbooks.
The NCAA has opposed gambling partnerships and has warned against betting products tied to college sports, especially prop bets and sports event contracts.