FIFA has filed a criminal complaint in Switzerland against Viagogo for selling tickets for this summer's World Cup in Russia.
The world football governing body stated that it had joined other parties filing criminal complaints against alleged "opaque and deceptive business conduct" by Viagogo in the so-called secondary market.
The priority is "the safety and security of fans and [to] enforce a fair 2018 FIFA World Cup ticketing pricing scheme," FIFA said in a statement.
Tickets to the tournament could be legitimately purchased only through FIFA's website, it added.
Earlier this year, FIFA successfully filed for a temporary injunction against Viagogo for advertising tickets to the World Cup before they had been allocated or issued.
