The ministry listed the platform's website under the country's Gambling Act. The law prohibits operators from offering unlicensed online gambling services to Czech users and obliges internet service providers to block access within 15 days after a site is published on the blacklist.
Polymarket operates as a prediction market, where users buy and sell contracts that depend on the outcomes of future events. The platform gained global attention during the 2024 US presidential election, and its markets were widely cited as an indicator of election trends. Polymarket and its rival Kalshi have been restricted by regulators in European Union countries including France, Germany, Poland, Romania and Spain.
Regulators in many countries argue that some prediction market contracts amount to unlicensed gambling or are subject to existing financial market rules. The European Securities and Markets Authority (ESMA) warned on July 3 that many prediction market contracts could fall within the current restrictions on binary options if they meet the definition of a financial instrument.
According to ESMA, companies cannot escape European Union finance rules by marketing binary options-like products as event contracts rather than derivatives. The authority stated that the evaluation depends on the characteristics of the contract and not on how the product is marketed. He added that companies offering contracts meeting this definition to individual investors may already be subject to national restrictions implementing the union's 2018 ban on binary options. ESMA also highlighted that companies offering these products to professional clients may need to obtain authorization under the Markets in Financial Instruments Directive (MiFID II).
Outside Europe, prediction markets have faced similar regulatory action. Australia, Indonesia and Singapore were among these countries. In the US, Kalshi and Polymarket have been targeted by regulators in many states over claims that their event contracts constitute illegal gambling. The Commodity Futures Trading Commission (CFTC) argues that these products fall under its exclusive jurisdiction as federally regulated derivatives.
The dispute has led to conflicting court decisions and calls for Congress to clarify whether sports and political event contracts should be treated as gambling or federally regulated derivatives.