Major League Baseball (MLB) has informed players that participation in prediction markets related to baseball results constitutes a breach of its gambling policies, as indicated in a memo that was shared during the 2025 season.
The memo, dated August 26 and titled “Re: Baseball Related Prediction Markets,” was released jointly by the office of Commissioner Rob Manfred and the MLB Players Association.
It emphasized that “engaging in ‘prediction markets’ where participants wager funds on any baseball game outcomes or events” is strictly prohibited. The memo highlighted multiple companies providing these markets, mentioning: “Several entities (such as Kalshi, Robinhood, and Crypto.com) currently offer what they refer to as ‘prediction markets,’ enabling the public to risk money on specific events, including baseball along with other sports.
The message was disseminated throughout Major and Minor League Baseball and was prominently posted near locker areas. Some players later informed Front Office Sports that they had not received details regarding the policy notification.
MLB acknowledged that related prediction markets involving baseball “recently came to our awareness.” Records indicate that Kalshi commenced offering MLB markets on April 16, more than four months prior to the memo’s distribution.
MLB has not clarified when it first identified baseball-related contracts or whether players who engaged in trading earlier in the season might face repercussions. The MLBPA opted not to comment.
Debate within the Industry on Market Definitions
Operators of prediction markets assert that they should not be classified as gambling entities, a view supported by federal agencies. Their contracts are accessible in areas where sports wagering is prohibited, leading to differing opinions from major professional leagues.
The National Hockey League (NHL) has established marketing agreements with Kalshi and Polymarket. The NFL has expressed concerns regarding limited regulatory oversight, asserting that the offerings “resemble sports betting.” The NBA is involved in an ongoing investigation concerning a player, a coach, and a former league member associated with a gambling issue. In May, NBA Assistant General Counsel Alexandra Roth requested “specific regulatory measures to mitigate related integrity risks” in a correspondence with the Commodity Futures Trading Commission.
Regulatory perspectives in Washington have changed following the prohibition of Polymarket in the United States during the Biden administration, only for it to be reintroduced under the current administration. Kalshi previously took legal action against the CFTC regarding election-based products, resulting in a ruling the agency eventually ceased contesting.
Concerns About Integrity and Data Access
MLB Vice President Bryan Seeley communicated to the CFTC in March that federal integrity protections are inadequate. “As the similarities between contracts related to sports events and conventional sports betting markets continue to escalate, the necessity for replicating the integrity and consumer protections currently present at the state level also grows,” Seeley remarked. He noted that the reporting of suspicious activities is not reliably guaranteed and some exchanges believe they are restricted from sharing pertinent data with the leagues.
Data alerts have previously aided investigations, including one involving Cleveland Guardians pitcher Luis Ortiz, who, along with teammate Emmanuel Clase, was charged with conspiracy to commit wire fraud and is currently on leave.
Actions and Licensing Challenges by State Regulators
Although federal regulators have permitted these markets to function, several states have indicated plans for enforcement. Michigan’s Gaming Control Board emphasized that engagement in sports-related event contracts “will impact your licensure in Michigan.” In Nevada, regulators stated that offering such contracts “constitutes wagering,” and infractions might jeopardize an operator’s license.
Ongoing legal disputes are present in New Jersey, Maryland, California, and Massachusetts. Arizona, Ohio, and Pennsylvania have also issued warnings to operators.
For MLB, the internal policy establishes a clear guideline for players amidst evolving legal and commercial landscapes. The league continues to collaborate with major sportsbooks like DraftKings and FanDuel, but has not formed similar partnerships with prediction market platforms such as Kalshi or Polymarket.