Poland's competition watchdog UOKiK is suing UEFA over the rules governing the sale of tickets to the 2012 European Championships, the regulator said on Friday.
European football's governing body and the Polish football association held a lottery in the country last year to allocate tickets for the June 8 to July 1 tournament, co-hosted by Poland and Ukraine.
Most fans were turned away, with the biggest pool of tickets going to various corporate sponsors.
The Polish regulator has raised several objections related to the sale, including the fans' inability to exchange the tickets and return them for a refund, its spokeswoman said.
A Polish court will consider the case on June 22, in the middle of the tournament.