MLB makes Polymarket its official prediction markets platform, giving it exclusive data access; Polymarket will restrict contracts that pose “integrity risk”

On the cusp of opening day and under the cloud of a recent betting scandal, MLB reaches a licensing agreement with event-prediction platform

Wall Street Journal 2026-03-19

Context & Ripple Effects

MLB’s arrangement follows the NHL’s earlier licensing deals with Kalshi and Polymarket, extending major-league acceptance of prediction-market branding and data relationships.

For Polymarket, the deal builds on its sports-contract monitoring partnership with Palantir and TWG AI, tying league access to more explicit safeguards around contracts that could threaten sporting integrity.

First-order effects

Polymarket gains official MLB status and exclusive access to MLB data, giving the platform a differentiated product and commercial relationship around baseball markets.
MLB gains contractual leverage over integrity-sensitive contracts, while Polymarket must restrict markets it judges to create integrity risk.

Second-order effects

Other prediction-market operators face a higher bar for league partnerships: official access may increasingly depend on accepting data, trademark, and market-governance conditions.
Polymarket’s surveillance and contract-review capabilities become more central to its sports offering, because any failure in those controls could jeopardize valuable league relationships.

Third-order effects

Sports leagues may increasingly treat prediction markets as regulated distribution and data partners rather than merely adjacent betting venues, with official status becoming a scarce competitive asset.
If this model spreads, market design and integrity controls—not only liquidity or user reach—could determine which prediction platforms can secure major sports licenses.

The trend: Prediction markets are moving toward league-sanctioned, data-linked sports products whose access is conditioned on formal integrity governance.

Discussion

@chairmanselig Mike Selig on x
Today the @CFTC and @MLB made history by signing the first-ever MOU between a sports league and federal agency. We've committed to work together to protect the integrity and resilience of prediction markets relating to professional baseball. Through this partnership, the [image]
@josephgruber.com Joseph Gruber on bluesky
No way this gets abused at all. No one in MLB at any level would ever abuse a betting market. Not a chance. [embedded post]
@timweston.com Tim Weston on bluesky
Wonderful 🙄 Add Polymarket to the list of companies actively and officially making the baseball-viewing experience worse. [embedded post]
@rjcurren Ray Curren on bluesky
Hope this gets a paragraph in Gibbon's The History of the Decline and Fall of the American Empire [embedded post]
@caseynewton Casey Newton on bluesky
Cool now every player can receive a death threat every game from someone trying to manipulate the market [embedded post]
@polymarket @polymarket on x
We're honored to announce MLB has named Polymarket as their Exclusive Prediction Market Exchange Partner. Polymarket 🤝 MLB [video]
@benhorney Ben Horney on x
Notable tidbit from ESPN on today's MLB-Polymarket deal.
@super70ssports @super70ssports on x
Put Pete Rose in the fucking Hall of Fame.
@foolishbb @foolishbb on x
What makes Polymarket worse than the sportsbooks is lack of regulation and profit incentive. I can at least trust that outlier betting patterns will unearth insider trading on DK or FD. They stand to lose money if there's an information gap. But not Polymarket. It's rife with it.
@sportradar @sportradar on x
As Major League Baseball's exclusive global data distributor and integrity partner, we look forward to playing an important role in this exciting and fast-growing market. Please see our full statement: [image]
@wallachlegal Daniel Wallach on x
“The MLB-Polymarket deal includes language that would void the partnership if courts were to rule that prediction markets violate state law, according to a league source.” via @DavidPurdum https://www.espn.com/...
@biasedslightly @biasedslightly on x
I'd be worried about this if there were any recent gambling scandals in the MLB but thankfully there hasn't been so I'm 100% on board with this
@tmathsports Taylor Mathis on x
We are exclusively with the MLB ⚾️🧢
@joshbtucker Josh Tucker on x
First job out of college — @Dodgers social media coordinator. Today, @Polymarket was named the official prediction market partner of @MLB.
@jaketodonnell Jake T. O'Donnell on x
The enduring legacy of Rob Manfred will be that he sold out the greatest sport ever created for every last dollar he could squeeze out of every entity no matter how shady to make his already-rich owners even more rich. That's what he'll leave behind.
@joonlee Joon Lee on x
Prediction Markets claim you're betting against other users, but you're really betting against Wall Street investors Prediction markets are sports gambling with a better PR strategy [video]
@matthewmodabber Matthew Modabber on x
Exclusive prediction market partner of the MLB Top of the 1st, bases loaded
@robtornoe Rob Tornoe on x
Last summer, MLB warned players not to use prediction markets and prohibited them specifically from using Polymarket.
@mikemayer22 Mike Mayer on x
NOPE
@tipping_pitches @tipping_pitches on x
is everybody done lauding Rob Manfred for what a great job he's done with the pitch clock and WBC now lol
@ntmoney Nick Tomaino on x
Free markets for sports is a better UX and better prices for people. In a few years the idea that free markets for sports was not the default will feel absurd. MLB is the first major sports league to get it A better sportsbook is not why we are here of course. Better information
@nickdevor_ Nick Devor on x
NEW: CFTC and MLB sign a memorandum of understanding, “a statement of intent to discuss, cooperate, and exchange information concerning issues of common interest, such as the integrity of professional baseball and the event contract markets related thereto...” The MOU does not,
@cftc @cftc on x
.@CFTC and @MLB Sign Groundbreaking MOU: https://www.cftc.gov/...
@thamosdeaf @thamosdeaf on x
Jesus fucking Christ man.
@bymattweyrich Matt Weyrich on x
Hey so this is the worst!
@benhorney Ben Horney on x
SCOOP: MLB is getting into the prediction-market business through a multi-year deal with Polymarket. Polymarket will be the exclusive prediction-market partner of MLB and will be the only platform allowed to use team logos and marks, sources tell @FOS. https://frontofficesports.c…

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