Spain’s Consumer Rights Ministry temporarily banned so-called prediction markets Polymarket and Kalshi ​for operating in the country without a ‌gambling licence, the official state gazette showed this week.

In a statement, the ministry said its gambling ​watchdog had opened a probe into the ​US-based companies for allegedly breaching local rules ⁠by lacking mandatory administrative authorisation.

The ban ​will last an estimated three or four months ​until the probe’s completion, it said.

Prediction market users buy and sell stakes on the outcome of future ​events, with prices reflecting the probability of ​one outcome or another occurring.

Spain – like other European jurisdictions – considers ‌prediction ⁠markets a form of gambling when bets are placed on uncertain outcomes.

The ministry said unauthorised operators lack the required technical and ​regulatory safeguards like ​identity verification ⁠systems, access control mechanisms for minors and for people who have ​self-excluded or are banned from gambling, ​as ⁠well as the standards needed to protect users.

Once a niche corner of the internet, prediction ⁠markets ​have mushroomed into a ​multi-billion-dollar industry after gaining a foothold in US politics in ​2024.