By Jared Diamond and Krystal Hur
Major League Baseball, the professional league still reckoning with its biggest betting scandal in decades, is plunging into the newest forum for wagers on sporting events: the prediction markets.
MLB signed a licensing deal with Polymarket, which as the league's official prediction-markets platform will have exclusive access to its data and iconography. Polymarket also agreed to work with MLB to restrict event contracts that pose "integrity risk," where outcomes triggered by the actions of, say, pitchers, managers or umpires could be subject to manipulation.
The agreement arrives with the baseball season's opening day just a week away, and with MLB dealing with the fallout from two of its players facing federal charges for allegedly manipulating their on-field performance.
Many pro sports leagues, including MLB, have aligned with traditional sportsbooks in recent years. But the sudden rise of the prediction markets, fueled by millions of traders eager to place "yes" or "no" wagers on sports and other real-world events, has opened a new front that a number of leagues have opted to no longer ignore.
The advent of prediction contracts hasn't been embraced by all. Several U.S. states have taken legal action to block event wagers from being accessed by their residents, and Polymarket only recently won approval to offer its platform to Americans.
In a related move, MLB signed a memorandum of understanding with the Commodity Futures Trading Commission, the government agency that regulates prediction markets. The document, which MLB Commissioner Rob Manfred and CFTC Chairman Michael Selig signed Wednesday, stipulates that the two sides will exchange information related to the competitive integrity of baseball games.
"In today's world, it is really important not to be chasing developments, but try to be involved and in front of those developments," said Manfred, speaking alongside Selig at a Miami hotel the morning after Venezuela beat Team USA to win the World Baseball Classic.
Professional sports leagues in America have at this point all embraced sports gambling, which is now legal in most of states. They have to this point been more wary of prediction markets, which allow users to bet on yes-or-no wagers on everything from the outcome of sporting events to election victories. The primary concern has revolved around their ability to identify suspicious activity that could threaten games.
In October, the National Hockey League became the first league to link up with Polymarket and its biggest rival, Kalshi, in an official capacity, believing that working directly with the platforms will give it the ability to help shape what sort of markets are offered.
Polymarket has a data partnership with Dow Jones, the publisher of The Wall Street Journal.
"Integrity was the foundation of the conversation, not something that was bolted on after we started discussions," said Ari Borod, Polymarket's president of sports business development. "We will continue to engage in a constant conversation with them about what is the best thing to do for the game of baseball, for our consumers and for the prediction market category as a whole."
The agreement with the CFTC is a new concept and could lay the groundwork for other leagues to follow suit. It effectively serves to open lines of communication between MLB and the CFTC, similar to relationships sports leagues currently have with state gambling regulators.
Perhaps most important, it is a sign that MLB is prepared to work with the federal government as it attempts to maintain its control over prediction markets. The Trump administration has continued to argue in favor of regulation at the federal level.
"We need to understand and work together with the league to know what could potentially be easily manipulated on the field," Selig said. "We don't necessarily have all that information from our background as a derivatives regulator."
All of this comes at a particularly perilous moment. The growing popularity of event-based contracts has raised concerns among lawmakers about customers using insider information and manipulating markets in their trades. Even beyond baseball, the American sports world has been rocked by multiple game-fixing schemes in the gambling sector, including in professional and college basketball.
At the same time, a debate has heated up about whether states can block prediction markets from offering sports-related bets at all. Battle lines are forming between federal and state officials arguing about how event contracts on prediction market platforms, including on sports, should be regulated, and by whom.
Nevada, the country's gambling capital, has emerged as a key battleground, with a federal appeals court in February rejecting Kalshi's bid for a stay on the state's efforts to block the platform. More recently, Arizona filed criminal charges against Kalshi's parent companies, accusing them of operating an illegal gambling business without a license.
Kalshi is regulated by the CFTC, as is Polymarket's U.S. platform launched late last year, which focuses primarily on sports and is smaller than its main international platform. Selig has recently come out swinging for prediction markets, and the commission in February filed a "friend of the court" brief with the appeals court, arguing it had exclusive jurisdiction over the commodities-derivatives market, including event contracts.
The issue could eventually reach the U.S. Supreme Court. Manfred said that MLB is "agnostic" on the legal situation surrounding prediction markets and is protecting itself within the current prediction-market landscape in the meantime.
"In the period of time that it takes for those legal issues to be resolved in a definitive way, it's incumbent on us to do everything we can to protect the integrity of the sport," he said.
Write to Jared Diamond at jared.diamond@wsj.com and Krystal Hur at krystal.hur@wsj.com
(END) Dow Jones Newswires
March 19, 2026 09:28 ET (13:28 GMT)
Copyright (c) 2026 Dow Jones & Company, Inc.
