Riot Games Explores Prediction Market Sponsorships Ahead of League of Legends World Championship
Riot Games has entered discussions with prediction market operators Kalshi and Polymarket regarding potential esports sponsorship agreements, according to a Bloomberg report published on September 11. The talks come weeks before the League of Legends World Championship kicks off in October.
Riot Evaluates Emerging Prediction Market Space
The Tencent-owned developer, which operates competitive tournaments for League of Legends and Valorant, has not committed to either platform. Sources familiar with the private discussions told Bloomberg that any agreement would involve Riot’s esports business.
“Prediction markets are an emerging space that we’re evaluating with a focus on safeguarding competitive integrity, potential value for teams, impact on the fan experience, and alignment with our broader ecosystem goals,” Riot Games spokesperson Joe Hixson told Bloomberg.
Kalshi declined to comment on the discussions, while Polymarket did not respond to Bloomberg’s request for comment.
Official Esports Data Requirement Through GRID
Any prediction market sponsor approved by Riot would be required to obtain official betting data through GRID Esports, one person familiar with the discussions told Bloomberg. GRID already maintains ties to Polymarket, having partnered with the prediction market operator in June. That agreement granted Polymarket access to official esports data and included plans for faster streams, a redesigned esports section, and data taken directly from game servers.
The requirement would place official game data within any sponsorship arrangement as Riot considers bringing prediction markets closer to its competitive ecosystem.
Massive Esports Betting Market Drives Interest
League of Legends and Valorant tournaments draw millions of viewers globally, with esports audiences skewing younger than those of traditional sports. Riot has previously cited Sportradar data showing betting tied to its two major titles reached $10.7 billion in 2024. Most of that activity took place through unregulated markets and unlicensed bookmakers, according to Riot.
The company began permitting sponsorships from traditional sports betting operators in 2025, subject to restrictions intended to protect competitive integrity. Prediction markets already offer contracts on esports matches, allowing traders to take positions on game outcomes without a formal sponsorship relationship with Riot.
Kalshi has been recruiting for an esports-focused position tasked with forming league partnerships and increasing its presence in the sector. Polymarket had employees working on esports by at least 2025, according to LinkedIn information cited by Bloomberg.
Prediction Markets Expand Across Professional Sports
The Riot discussions would extend a series of deals bringing prediction markets into professional sports and entertainment. At the end of August, Kalshi secured an exclusive U.S. Open partnership with the U.S. Tennis Association. The agreement gave the company prediction market partner status and restricted competing platforms from advertising at the tournament venue and across its television coverage.
Kalshi had already gained FIFA World Cup exposure through an agreement with ADI Predictstreet, FIFA’s official prediction market partner for the 2026 tournament. The World Cup partnership placed Kalshi branding alongside ADI Predictstreet across stadium, television and digital coverage during the competition.
Polymarket has pursued a similar strategy, signing agreements spanning Major League Baseball, the Bundesliga and other sports properties. Its Bundesliga agreement made Polymarket the league’s exclusive U.S. prediction market partner and included the use of market data during pay-per-view programming.
NBA star LeBron James became one of the latest prominent athletes connected with the company when he confirmed a Polymarket partnership through a video posted on X on September 5. The initial campaign is expected to focus on American football, according to CNBC.
Record Trading Volumes Fuel Competition
Prediction market operators have been competing for sports users as trading activity across the sector has climbed. Combined monthly volume across Kalshi, Polymarket and Polymarket US reached a record $50.59 billion in July, with Kalshi accounting for $37.7 billion.
Integrity Concerns Shape Riot’s Evaluation
Riot’s consideration of prediction market sponsors comes as sports organizations take different positions on partnerships with the sector. The National Football League has held back from signing prediction market sponsorships, citing concerns over inadequate regulation and ongoing legal challenges, Bloomberg reported earlier this month.
Riot has its own concerns because betting activity can create integrity risks around professional matches. Its evaluation of prediction markets is therefore considering competitive integrity alongside the possible financial benefits for esports teams and effects on fans, according to Hixson.
Sponsorship income remains an important source of revenue for esports organizations. NewZoo estimates that sponsorships can account for as much as 60% of an organization’s revenue, while the industry has historically struggled to generate sufficient income from merchandise and ticket sales.
Prediction market companies have spent heavily to place their brands around major sporting events while developing systems intended to detect prohibited trading. Kalshi uses its proprietary Poirot detection system and has worked with Solidus Labs, IC360 and the Wharton Forensic Analytics Lab on surveillance and integrity controls. Polymarket has developed Vergence AI, an integrity monitoring system created with support from Palantir and TWG AI.
Regulatory Battles Continue Across States
Sports contracts remain one of the main sources of regulatory pressure on Kalshi and Polymarket in the United States. State gaming regulators and attorneys general have argued that contracts tied to game winners, player statistics and other sporting outcomes amount to sports betting and should fall under state gambling laws. Prediction market operators have countered that their event contracts are derivatives subject to federal oversight.
The dispute has produced different outcomes across U.S. courts. A Washington state judge in July granted a preliminary injunction blocking Kalshi from offering sports prediction markets to residents after finding the state was likely to succeed in arguing that the products violated local gambling laws. Kalshi has faced similar challenges in New York and Michigan, while lawsuits involving prediction market regulation have spread across numerous states.
Baltimore sued both Kalshi and Polymarket in August, accusing the companies of offering unlicensed sports betting. The city’s case against Kalshi named Coinbase, Robinhood and Webull over their role in distributing sports event contracts.
Despite the legal disputes, sports have become a major source of activity for prediction markets. During the 2026 FIFA World Cup, monthly sports prediction volume reached $9.5 billion on Kalshi and $5.3 billion on Polymarket, according to Defirate data reported in June.
Riot’s discussions are taking place weeks before the League of Legends World Championship begins in October. No sponsorship agreement with either Kalshi or Polymarket has been announced.
