Police searched 11 properties in Frankfurt, the wider Rhine-Main region and Cologne as part of an investigation into an illegal online casino network that took around €5.86 billion in stakes between July 2021 and the end of 2023, according to the Frankfurt am Main public prosecutor’s office.
More than 100 police officers, prosecutors and tax investigators took part, working alongside tax authorities in North Rhine-Westphalia. Five people are accused of commercial and organised provision of unlicensed online gambling and aggravated tax evasion. An arrest warrant issued by the Frankfurt District Court was executed against the main suspect.
Investigators put the tax loss at about €77.6 million and secured roughly €82 million in assets, including several high-value vehicles and frozen bank accounts.
Stakes of €2.34 billion a year
The €5.86 billion covers two and a half years, an average of about €2.34 billion a year. Germany’s licensed virtual slots operators took €4.57 billion in stakes across the whole of 2025, according to the figures in the German online casino market report. On that basis, a single unlicensed network was running at more than half the annual volume of the entire regulated slots vertical.
The two numbers measure different things. The €5.86 billion is turnover, the amount wagered, while the regulator’s black market estimates are expressed as a share of online gross gaming revenue (GGR). A direct percentage comparison does not hold. The scale of the turnover is what the industry is pointing at.
Two estimates, 33 points apart
The Gemeinsame Glücksspielbehörde der Länder (GGL), Germany’s national gambling regulator, estimated that unlicensed operators accounted for 23% of online GGR in 2024, worth about €547 million. A 2025 study commissioned by the Deutscher Online Casinoverband (DOCV) and the Deutscher Sportwettenverband (DSWV) put the unlicensed share at 56%.
The GGL has also published research putting channelisation at 77%, the mirror image of its 23% figure. The Frankfurt case has given the associations a hard number to set against it.
“Without question, this operation is a success. But it also shows that the illegal online gambling market is flourishing. The figures from the investigation do not fit with the authority’s estimates. This discrepancy is too large and must be explained by the GGL. Its figures paint too small a picture of the black market,” said Kevin O’Neal, a member of the DOCV executive committee.
The cost gap between licensed and unlicensed
Germany has taxed virtual slot stakes at 5.3% of turnover since July 2021, the month from which prosecutors date the network’s recorded activity. That tax is the basis of the evasion charge, and it is a cost unlicensed sites do not carry.
Licensed operators also work under product rules that unlicensed sites ignore: a €1 maximum stake per virtual slot spin, a five-second minimum spin duration, and a €1,000 monthly deposit limit applied across all licensed operators through the central LUGAS file. Those rules were set to reduce harm, and they also set the terms on which the two markets compete for the same players.
What the regulator can and cannot do
The GGL’s enforcement tools are takedown demands, advertising bans and payment blocking. Its attempts to order internet service providers to block unlicensed sites have been challenged in the administrative courts. Criminal investigations of the kind run in Frankfurt sit with state prosecutors and tax investigators, not with the regulator.
The GGL reported in July that 254 illegal operators had left the German market after its interventions. Those exits are counted by operator, not by turnover, which is part of why the two sides of this argument keep talking past each other.
What happens next
The investigation is continuing and no charges have been brought. The five suspects have not been named and the presumption of innocence applies.
The DOCV is using the case to press for changes to the Interstate Treaty on Gambling (Glücksspielstaatsvertrag), specifically on enforcement against unlicensed operators and on the tax and product rules that shape the cost gap. The next concrete test is whether the GGL revises its methodology in its coming annual report. If it does not, the 23% estimate and the 56% estimate will both be on the table when the treaty is reviewed, and operators will keep citing the one that matches the size of the networks prosecutors are finding.
Source: Frankfurt am Main Public Prosecutor’s Office
