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Bonus TL;DR
- LeBron James teased a Polymarket partnership after his DraftKings deal ended, marking a major celebrity tie-up for prediction markets.
- Polymarket faces rapid growth and sports league endorsements alongside municipal lawsuits alleging the platform operates as an unlicensed sportsbook.
LeBron James has teased a Polymarket campaign on X, with the company saying it will fully reveal the deal Tuesday, in a new celebrity partnership that could raise the profile of prediction markets in U.S. sports.
The partnership matters because James is one of the biggest names yet to align with the sector as prediction markets compete more directly with traditional sportsbooks. It also comes shortly after his endorsement deal with DraftKings expired earlier this summer, according to BeInCrypto.
In the teaser video, James said: “Welcome to Polymarket HQ. Coming soon. 👀” Polymarket said more details would be released Tuesday, but the company had not disclosed the campaign’s exact terms or what product James will promote.
Why the deal stands out
The move adds a mainstream sports figure to a fast-growing category. BeInCrypto reported that prediction market volume topped $20 billion a month by January, up from about $1.2 billion in early 2025.
Markets tied to James himself have already shown the scale of user interest. Betting on his next team drew more than $245 million in volume this summer, the report said.
The endorsement also lands as leagues take different approaches to prediction market relationships. According to the report, the NBA allows players to endorse prediction markets but bars them from promoting contracts tied to NBA games. The NFL and PGA Tour reportedly ban those deals outright.
Other sports tie-ups have followed. Major League Baseball named Polymarket its official prediction market provider, while the NHL struck deals with both Polymarket and Kalshi in October 2025. Earlier this year, Giannis Antetokounmpo also became a Kalshi shareholder.
Growth continues as legal fights remain in the background
The business backdrop is strong even as legal pressure persists. BeInCrypto said Polymarket sought $400 million in April at a $15 billion valuation, up from $9 billion last October. The outlet also reported that Intercontinental Exchange has committed $2 billion to Polymarket.
At the same time, prediction markets still face challenges from regulators and local governments. Baltimore sued Polymarket and Kalshi in August, calling them unlicensed sportsbooks, while New York sued Kalshi in July for more than $36 billion, according to the report.
What comes next in James’s case is narrower: Polymarket has promised a full announcement on Tuesday. The main open questions are what the campaign includes, whether it focuses on sports-related markets, and how league endorsement rules will apply in practice.
Source: As reported by Phil Haunhorst.
