Europe's betting industry has made a formal complaint to the EU against a German ban on online gambling.
Germany's state-run lotteries continue to operate
Under the law which came into force on 1 January, online gaming and betting are prohibited, although horse racing is allowed.
The European Gaming and Betting Association (EGBA) says the ban breaks EU law and is totally impractical.
German states argue they are protecting consumers but critics say they are trying to preserve state-run lotteries.
EGBA secretary general Sigrid Ligne says: "The official claim is consumer protection and we feel that claim is unjustified."
"Why focus on internet gambling when traditional land-based offline gambling is being promoted in Germany?"
The European Commission says it does not believe the German legislation is compatible with EU law, and has already acted launched legal action.
The commission insists it is not preventing member states from protecting the public.
Spokesman Oliver Drewes said the problem was that Germany, in common with other countries, was trying to restrict certain types of gambling while leaving others, particularly state lotteries, alone.
"You have to have the same rules for everybody and not a situation where different operators are treated in a different way," he said
Mr Drewes said 10 member states were currently the subject of legal action on gambling, including Denmark, Sweden, Finland and Hungary.