Lisbon, Jan 21: Portugal’s gambling regulator has ordered prediction market platform Polymarket to cease operations in the country after more than 4 million euros were wagered on its presidential election markets in the hours before official results were announced, raising concerns over the use of non-public information.
The order was issued by Portugal’s gambling authority SRIJ, which said Polymarket is illegal under national rules that restrict online gambling to licensed sports betting, casino-style games and horse racing, and do not permit political event markets. The regulator said it had only recently become aware of Polymarket’s activity in the country.
Trading on the platform drew attention on Sunday as heavy betting took place shortly before results from the first round of Portugal’s presidential election were released. Portuguese broadcaster Rádio Renascença reported that more than 4 million euros ($4.3 million) was wagered during that brief period, prompting questions over whether bets were informed by leaked exit polls or other non-public data.
In the election, Socialist Party candidate António José Seguro led the first round with 31% of the vote, followed by far-right Chega candidate André Ventura on 24%. Neither secured the 50% needed to win outright, sending the contest to a runoff between the top two finishers.
On election day, Seguro’s implied probability on Polymarket rose sharply. His odds climbed from around 60% early in the afternoon to about 95% by around 6 p.m., roughly an hour before polls closed. After exit-poll projections began circulating, but before official results were released, his odds approached near certainty on the platform.
Authorities said there is currently no evidence of insider trading. The timing of the odds swing coincided with the spread of exit-poll information, suggesting the market was rapidly absorbing new data, though whether that information was shared appropriately remains a matter for Portuguese authorities.
Portugal’s move adds to growing scrutiny of political prediction markets operating outside traditional gambling and financial frameworks. Polymarket has faced regulatory action elsewhere, including in the United States, where it reached a 2022 settlement with the Commodity Futures Trading Commission over unregistered event-based contracts and agreed to block U.S. users.
Ahead of the most recent U.S. presidential election, the CFTC also sued rival platform Kalshi to stop it from offering election outcome contracts, though a federal court declined to grant the requested relief.
Operators of prediction markets argue that election contracts provide useful signals for forecasting outcomes and hedging political risk. Critics counter that the products amount to gambling under another name and warn they could undermine confidence in electoral processes.
