MLB Signs With Polymarket & the CFTC, Choosing a Side in a War States Are Losing

Major League Baseball (MLB) named Polymarket its exclusive prediction market exchange partner on March 19. They signed a multiyear deal reportedly worth up to $300 million alongside a first-of-its-kind agreement with the Commodity Futures Trading Commission (CFTC).

The announcement landed just two days after Arizona filed the first criminal charges against Polymarket rival Kalshi, turning America’s oldest pastime into the highest-profile endorsement yet for a crypto-native industry under legal siege.

MLB’s Polymarket Deal Puts Baseball Behind Crypto in a Federal vs. State Showdown

MLB Commissioner Rob Manfred and CFTC Chairman Michael Selig signed a memorandum of understanding (MOU), the first between the federal regulator and a professional sports league.

The agreement establishes information sharing and regular discussions on market integrity related to baseball.

Manfred framed the CFTC’s federal jurisdiction as the key differentiator from state-regulated sports betting.

The distinction matters. More than 20 civil lawsuits and cease-and-desist orders from states challenge whether prediction markets fall under gambling regulations.

Arizona escalated the fight on March 17 by filing 20 criminal misdemeanor counts against Kalshi, calling it an unlicensed gambling operation.

CFTC Chairman Selig responded, calling the criminal prosecution “entirely inappropriate” and a “jurisdictional dispute.” He added that the agency was “watching this closely.”

MLB’s timing sends a signal. By signing with the CFTC and Polymarket simultaneously, the league effectively endorsed the position that prediction markets belong under federal derivatives law, not state gaming commissions.

A Crypto Platform Goes Mainstream

Polymarket operates on the Polygon blockchain and settles all trades in USDC, the stablecoin issued by Circle. Users trade yes/no outcome shares priced between $0.01 and $1.00, with prices reflecting crowd-sourced probability estimates.

The platform processed $33.4 billion in global trading volume in 2025. In October of that year, Intercontinental Exchange (ICE), the operator of the New York Stock Exchange, invested $2 billion in Polymarket at a $9 billion valuation.

Under the MLB deal, Polymarket and its brokers gain exclusive access to league logos, marks, and official data distributed by Sportradar. The platform also receives promotion across MLB’s digital ecosystem and at league events.

Sources told Front Office Sports the deal could be worth $300 million over three years, though another source placed the initial figure closer to $150 million with extension options.

MLB follows the National Hockey League (NHL), Major League Soccer (MLS), and the Ultimate Fighting Championship (UFC) in formalizing prediction market partnerships.

The National Football League (NFL), the National Basketball Association (NBA), the PGA Tour, and the National Collegiate Athletic Association (NCAA) have not signed similar deals.

The Kill Switch in the Fine Print

The deal includes a clause that would void the partnership if courts rule prediction markets violate state law. That provision acknowledges the legal uncertainty still surrounding the industry.

Both MLB and Polymarket agreed to restrict markets that pose integrity risks, including those tied to individual pitches, manager decisions, and umpire performance.

Polymarket will also embed integrity controls into its US rulebook to ensure the same standards are applied across all its brokers.

“Integrity was at the foundation of this deal. It wasn’t something that we figured out after the fact,” stated Ari Borod, president of sports for Polymarket (ESPN)

The irony is hard to miss.

Last summer, MLB warned its own players against using prediction markets, framing the practice as a violation of sports betting rules. Now the league is getting paid to legitimize the very platforms it once prohibited.

A bipartisan bill introduced in the House would prohibit event contracts on sports unless a state specifically permits them, and would ban prediction markets on elections entirely.

Meanwhile, a recent Ipsos poll found 61% of Americans view prediction market event contracts as closer to gambling than investing.

Whether MLB’s bet pays off hinges on a legal fight likely headed to the Supreme Court.

Conflicting federal court rulings across multiple states have created a jurisdictional split that the Court typically resolves.

Until then, Polymarket has baseball’s blessing, a federal regulator in its corner, and a kill switch in the contract just in case.