NBA Players and Prediction Markets

As the NBA prepares for the start of its 2026-27 season, partnerships between some of the league's biggest stars and prediction market companies are drawing attention, raising questions about gambling endorsements, league regulations and the potential use of inside information.

LeBron James and Giannis Antetokounmpo have entered into agreements with prediction market platforms in recent months, while San Antonio Spurs star Victor Wembanyama has publicly criticized players who promote gambling-related businesses.

James, who is preparing for his first season with the Philadelphia 76ers, reportedly signed a $15 million annual endorsement agreement with Polymarket in September. According to Front Office Sports, the deal will pay James nearly four times his $3.9 million NBA salary for the upcoming season.

Under the agreement, James is expected to promote football-related prediction markets rather than basketball betting. He previously entered into a promotional partnership with DraftKings in 2024.

Prediction markets allow users to trade contracts based on the outcomes of future events, including sporting events, political elections and other developments. Platforms such as Polymarket and Kalshi operate under a regulatory framework that differs from traditional sportsbooks, although their sports-related offerings have faced legal challenges over whether they should be subject to state gambling laws.

James' agreement follows a separate partnership announced in February between Milwaukee Bucks star Giannis Antetokounmpo and Kalshi. Unlike James, who serves as a paid endorser, Antetokounmpo acquired an ownership stake in the company.

The timing of both agreements has attracted attention because the platforms previously offered markets involving the players' futures in the NBA.

Before James joined Philadelphia, more than $46 million in trading activity reportedly occurred on Polymarket contracts tied to his next team. Kalshi also reportedly handled approximately $25 million in trading related to Antetokounmpo's potential departure from Milwaukee ahead of the February trade deadline.

There is no evidence that either player traded on those markets, disclosed confidential information or violated NBA regulations.

The NBA currently permits players to enter into endorsement agreements with prediction market companies, although restrictions apply to ownership interests and gambling-related activities.

NBA Commissioner Adam Silver addressed the issue during All-Star Weekend in February, explaining that players cannot hold an ownership stake greater than 1% in a gambling or prediction market company.

The league has also expressed concerns about certain types of prediction markets, particularly those involving player transactions.

In an April filing with federal regulators, the NBA urged restrictions on markets involving player movement, citing the possibility of manipulation and the misuse of confidential information. Unlike the outcome of a basketball game, a player's decision to sign with a particular team may be known to a limited number of people before becoming public.

The issue has created questions about how professional sports leagues should regulate the growing prediction market industry while allowing athletes to pursue outside business opportunities.

Not every NBA star supports the growing number of gambling-related endorsements. Wembanyama, the San Antonio Spurs center and reigning NBA Defensive Player of the Year, addressed the subject during a conversation with reporters on Oct. 1.

"Absolutely not. I will never do that. Honestly, I think it's very sad to see some players promote it. Everybody does whatever they want, but without me," Wembanyama said when asked whether he would consider endorsing a sports betting or prediction market company.

Wembanyama also explained that financial compensation is no longer a primary consideration when deciding which companies to represent. He said he has declined endorsement opportunities worth more than the money he has earned from partnerships because they did not align with his personal values.

The debate extends beyond individual endorsement agreements. State regulators and prediction market operators are involved in legal disputes over who has authority to oversee sports-related event contracts.

Prediction market companies have argued that their contracts fall under federal oversight by the Commodity Futures Trading Commission, while state officials have maintained that certain sports-related contracts should be regulated as gambling.

The distinction affects licensing requirements, consumer protections and the rules governing which events can be offered for trading. For the NBA, the issue also involves maintaining public confidence in the integrity of its games and player transactions.

With the 2026-27 season approaching, James and Antetokounmpo's business arrangements, Wembanyama's public opposition and the league's concerns about prediction markets have brought renewed attention to the relationship between professional basketball and the expanding gambling industry.