Blumenthal Pushes Sports Leagues to Detail Gambling Partnerships

^{Blumenthal wants major sports leagues to come clean about their partnerships with prediction markets and sportsbooks. (Photo: Annabelle Gordon / CNP / MediaPunch)}

Senator Richard Blumenthal (D-Connecticut) issued a letter to six major sports leagues on April 9, asking them to reveal the extent of their gambling partnerships, including how they are maintaining game integrity and complying with state gaming laws.

The letters were sent to executives of Major League Baseball (MLB), the NFL, the NBA, the NHL, Major League Soccer, and the NCAA.

Blumenthal: ‘Gambling Has Permeated Every Aspect’ of Sports

In his letters, Blumenthal asked the leaders of each league to answer seven questions related to sports betting partnerships by May 1, 2026. Those included asking for a complete list of all partnerships each league has with sportsbooks, prediction markets, and service providers, as well as asking how each league makes sure its partnerships do not violate state laws and what data is shared with partners.

While the letters all read similarly, the names of various betting partners were changed to be relevant to each league, like mentioning MLB’s new partnership with Polymarket. Regardless, however, Blumenthal made the same plea to each organization.

“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,” Blumenthal wrote. “Commercial breaks during games are littered with ads for sportsbooks and prediction markets, discussions of betting and spreads are a staple of sports news and commentary, and gambling companies sponsor teams and stadiums."

Though sportsbooks and prediction markets have skyrocketed in popularity, they come with a human cost as well, according to Blumenthal:

"Sports bettors have wagered over $600 billion since 2018, two and a half million Americans have a severe gambling problem, and five to eight million more have at least a moderate gambling problem.”

Blumenthal argued that the sheer volume of gambling branding and advertising in sports has made it nearly impossible for fans to escape reminders about betting — a situation he called "dangerous" for those struggling with problem gambling. He called on the MLB specifically to cut ties with gambling operators that he believes undermine the integrity of the game, back stronger state and federal oversight, and require meaningful protections against addiction, fraud, and exploitation in any future contracts.

Federal Lawmakers Looking to Assert Control of Betting, Prediction Markets

Of the six organizations contacted, the NCAA is the only one that does not partner with any sportsbooks or prediction markets, though it does share data with licensed sportsbooks. 

This isn’t Blumenthal’s first stab at reining in the sports betting industry. In both 2024 and 2025, the Connecticut Senator partnered with Representative Paul Tonko (D-New York) to introduce the SAFE Bet Act in Congress, which would regulate sports betting at the federal level and require states to obtain Department of Justice approval for their sports betting regulations.

Blumenthal has also recently introduced legislation designed to ban insider trading on prediction markets and clarify that sites like Kalshi and Polymarket are not exempt from state regulations. More recently, Senators Adam Schiff (D-California) and John Curtis (R-Utah) introduced the Prediction Markets Are Gambling Act, which would prevent prediction markets from offering sports-based contracts.