Polymarket is taking the Netherlands Gambling Authority, Kansspelautoriteit (KSA), to court over a €420,000 penalty linked to the prediction-market platform’s operations in the Dutch market.
The dispute involves Adventure One QSS Inc., the company operating Polymarket. The KSA determined that the platform had been offering gambling services in the Netherlands without the required licence and ordered the company to stop serving Dutch users.
In February 2026, the regulator formally instructed Polymarket to withdraw from the market, warning that Adventure One could face penalties of €420,000 per week, up to a maximum of €840,000, if the platform remained accessible. The KSA said prediction markets fall within Dutch gambling law despite Polymarket’s argument that its contracts function as tradable markets rather than conventional betting products.
The disagreement now centres on how quickly Polymarket implemented the required block.
According to the KSA, the deadline for ending access was 17 February, while Polymarket’s withdrawal became effective on 18 February. The regulator subsequently concluded that Adventure One had breached the enforcement order and imposed a €420,000 payment.
Adventure One argued that it had already begun introducing technical restrictions on 18 February and that some users were temporarily still able to reach the platform while the blocking measures were being deployed and tested. The company maintained that the remaining access resulted from technical implementation rather than a deliberate failure to comply.
The KSA rejected that explanation. In May it decided to recover the €420,000, and in July confirmed publicly that the penalty had become payable. Adventure One has since challenged the decision and is seeking to overturn the sanction through proceedings in The Hague.
The case comes as Dutch policymakers continue to debate how prediction markets should be treated under national law. A proposal to create a separate regulatory framework for the sector was recently raised in the House of Representatives, although the government has maintained the KSA’s position that the products are gambling activities subject to existing rules.
Prediction markets are receiving increasing regulatory attention elsewhere in Europe as well, with authorities considering whether event contracts should fall under gambling, financial-market or potentially new specialised regimes.
For the Netherlands, however, the KSA’s current position remains clear: platforms offering prediction-based wagering to Dutch consumers require appropriate authorisation, and operators without a licence can face enforcement action.