Major League Baseball (MLB) has announced an agreement with Polymarket, naming the platform as its official prediction market partner. The agreement marks the rising prominence of prediction markets, alongside sportsbooks, and grants Polymarket the right to use official logos.
The New York-based platform will also gain access to Sportradar's league data and exposure through MLB's digital and on-field events.
Meanwhile, the league has also signed a first-of-its-kind Memorandum Of Understanding (MOU) with the Commodity Futures Trading Commission (CFTC). The pair will share data and maintain a clear line of communication to ensure baseball's integrity amid growing concerns about insider trading in prediction markets.
The prediction market debate
Prediction markets rose to prominence during the 2024 US election. Platforms including Polymarket and Kalshi took more than one billion dollars in contracts during the event, and their predictions proved considerably more reliable than those of professional pollsters.
While they have proven popular, the platforms continue to tread a narrow line on legality and morality. The CFTC claims jurisdiction over the platforms, labeling them as trading. This has allowed members to trade on sports events in US States where sports betting is still prohibited.
But many states debate the CFTC's position.
The Nevada Gaming Control Board secured a temporary restraining order against Kalshi. Arizona, Massachusetts, New York, and Michigan are some other states that have taken similar action.
The platforms have also been accused of facilitating insider trading. Large positions were taken in the lead-up to the detainment of Venezuelan President Nicolas Maduro, and before the US strikes on Iran.
Growing popularity of prediction markets
Despite the controversy, user growth has continued unabated. What was a $50bn market in 2025 is expected to grow to $1tn by 2030 – prediction platforms have become difficult for leagues to ignore.
The UFC announced a partnership with Polymarket in November after the NHL signed deals with Polymarket and Kalshi in October last year. The MLS and Polymarket signed a similar arrangement in January this year.
And while the NFL continues to push back against the platforms, it seems likely to be a matter of time before they follow suit, having originally pushed back against sports betting before subsequently signing deals with companies including BetMGM and PointsBet.
Ensuring MLB league integrity
The MLB has taken steps to help limit the risk of insider trading and possible match fixing, coming just months after pitchers Emmanuel Clase and Luis Ortiz were charged with fraud.
The league said in a press release: "A key component of the partnership between MLB and Polymarket will be establishing a comprehensive integrity framework, which includes working together to restrict markets that present an integrity risk to MLB, such as individual pitches, manager decisions, and umpire performance, among others.
"Polymarket will also integrate integrity controls into its US Rulebook to ensure all of its brokers are held to the same integrity standards."
Meanwhile, Polymarket's Founder and CEO, Shayne Coplan, reiterated the point, saying: "Polymarket is about bringing fans closer to the moments that define sports. By working collaboratively with Major League Baseball and regulators, we can create new ways for fans to engage with the game while protecting the integrity of the sport."
