Pro sports has been rocked by gambling scandals and the rise of prediction markets, but Mark Cuban says the real problem isn’t sports betting itself—it’s the explosion of prop bets and the culture of scrutiny and abuse they have fueled.
“Sports betting is not the problem,” Cuban told Front Office Sports during the latest episode of Portfolio Players. “Whether it’s Kalshi or traditional sports betting, it’s the prop bets that are the problem.”
Prop bets involve putting money on specific outcomes, often tied to an individual player—like how many points Victor Wembanyama will have in Game 2 of the Western Conference Finals or the number of strikeouts Shohei Ohtani will have in a given game—but also including wagers on who will win a series MVP award or even the outcome of a single pitch or at-bat.
These sorts of wagers have been behind the recent gambling scandals in the NBA and MLB. In the former, Jontay Porter was banned from the league for life after admitting to manipulating his own stats for bettors and Terry Rozier was indicted for allegedly doing the same; in the latter, Guardians pitchers Emmanuel Clase and Luis Ortiz were both indicted over charges that they rigged individual pitches to benefit gamblers.
“I don’t think we fully considered all the permutations of betting that would be created, and the simplicity of betting online,” Cuban told FOS.
There have been no sports-related scandals on that level related to bets placed on prediction markets, although Polymarket’s offshore platform was used by a U.S. soldier who last month was indicted over claims he used inside information to make more than $400,000 trading on when the U.S. military would capture Venezuelan president Nicolás Maduro. All the major leagues are concerned the proliferation of platforms like Kalshi and Polymarket could bring about more integrity issues.
The Commodity Futures Trading Commission is in the process of putting together new rules that will govern the prediction-market industry, and leagues have made clear that prop bets should be a focus. Some leagues, like the NHL and MLB, have entered into agreements with platforms.
The former Mavericks majority owner said the deals that have been struck between leagues and platforms were not made because of the “money or the data feeds,” but instead “because they want to limit the types of predictions or bets.”
Unlike NCAA president Charlie Baker, who has called for nationwide prop-bet prohibition in college sports, Cuban isn’t pushing for a complete ban on prop bets; betting on what the score will be at the end of a given quarter, for example, isn’t inherently bad, he said.
“But now, when you’re betting ‘does a guy pick his nose at the free throw line with under six minutes, up by more than 12?’ That creates a lot of perverse incentives,” Cuban told FOS.
He is particularly troubled by the impact the rise of prop bets has had on players. In addition to those like Rozier and Clase, who found themselves involved in allegedly illegal activity, players face intense scrutiny from fans who have placed prop bets related to their performance. That scrutiny can include curses hurled at players from the stands, as well as vulgar complaints lodged on social media platforms.
“We have not done a good job of protecting players as much as we should, particularly on social media,” Cuban said.
