The Netherlands Gambling Authority has rejected an appeal by Polymarket operator Adventure One QSS Inc., confirming that the prediction market platform offered unlicensed gambling to Dutch consumers.
The Kansspelautoriteit, commonly known as the KSA, upheld enforcement orders originally issued on 20 January. The regulator concluded that users were able to stake money on uncertain future events for the chance to receive a payout, bringing the activity within the definition of gambling under Dutch law.
Adventure One was ordered to stop serving the Dutch market and received four weeks to comply. That period expired on 17 February, but a subsequent KSA inspection found that the violation had not ended by the deadline.
The company introduced measures to block Dutch IP addresses on 18 February. However, the regulator ruled that these controls had been activated too late and that a financial penalty had therefore become payable automatically.
Adventure One challenged both the enforcement order and its public disclosure in an appeal submitted in March. It also requested reimbursement of its legal costs.
The operator argued that Polymarket was not comparable to a conventional sportsbook or online casino. It described the site as an interface through which customers trade positions with one another using an open-source protocol on the Polygon blockchain.
According to Adventure One, the company does not manage customer cryptocurrency, control the underlying protocol or determine winning outcomes. Settlements are instead carried out through an external oracle after an event has been resolved.
It also said user returns depend partly on research, information, timing and the ability to adjust positions, rather than solely on chance. The company further pointed to the treatment of some prediction markets as financial products in other jurisdictions.
The KSA dismissed those arguments. It said a platform can provide access to gambling even when it acts mainly as a facilitator and does not compete directly against customers. Peer-to-peer structures already exist in regulated activities such as poker, football pools and betting exchanges.
Blockchain technology, cryptocurrency wallets and decentralised infrastructure also do not place a product beyond the reach of Dutch gambling legislation, the authority found.
The regulator noted that Polymarket had itself used gambling-related language in its marketing, including references to profiting by betting on future events.
Dutch legislation permits licensed online operators to offer casino games, sports betting and wagering on horse racing. Betting on unrelated future events, including elections, political developments and player transfers, is not permitted even under a Dutch remote gambling licence.
Polymarket carried both event-based and sports markets, according to the investigation. The platform was also readily accessible from Dutch IP addresses and offered a Dutch-language AI customer support function.
Markets connected to Dutch political figures and athletes provided further evidence that consumers in the country could use the service.
The KSA therefore concluded that Polymarket gave Dutch residents an opportunity to compete for prizes determined by events over which individual participants had no decisive influence.
Adventure One also claimed the enforcement action was disproportionate, insufficiently justified and legally uncertain. Those objections were rejected, as was its argument that publication amounted to unfair “naming and shaming.”
The regulator said disclosure served legitimate purposes, including warning consumers, improving transparency and discouraging other companies from operating without authorisation. The request for legal-cost reimbursement was also denied.
The decision, dated 23 June, can still be challenged before a Dutch administrative court. An appeal would not automatically suspend the enforcement order.
The ruling comes as European authorities increase their scrutiny of prediction markets. Regulators from nine countries, including the Netherlands, France, Germany, Spain and Italy, recently agreed to cooperate against platforms that do not comply with domestic licensing rules.
Their concerns include continuous access, weak identity and age checks, the absence of betting or time limits, possible insider activity and the risk of consumers losing access to their funds.
At the same time, the European Securities and Markets Authority has clarified that certain event contracts may qualify as financial instruments. Contracts tied to recognised financial underlying assets can be treated as derivatives, while binary products meeting that definition are generally prohibited from being marketed or sold to retail clients under national intervention measures.
ESMA also stressed that not every event contract is a financial instrument and that some may instead be governed by national gambling laws or European crypto-asset rules. The label attached to a product does not determine its legal status.