The Alleged Owner of the Biggest File-Sharing Site Has Been Arrested by David Meyer @FortuneMagazine July 21, 2016, 6:16 AM EST E-mail Tweet Facebook Linkedin Share icons The Polish authorities have arrested a Ukrainian man named Artem Vaulin for allegedly running the most popular file-sharing site, Kickass Torrents (KAT). The U.S. is now seeking Vaulin’s extradition, and has charged him with counts of copyright infringement, conspiracy to commit copyright infringement, and conspiracy to commit money-laundering. American authorities have also requested the seizure of KAT’s servers in the U.S., Costa Rica and the Philippines. Get Data Sheet, Fortune’s technology newsletter. KAT provides a searchable index of .torrent files, which can give people access to copyrighted TV shows, movies or software. Captain America: Civil War is named in one of the charges against Vaulin. According to the U.S. Department of Justice, KAT gets 50 million unique visitors each month and is the 69th most-visited site on the web, earning its operators tens of millions in annual ad revenue. The DoJ claims Vaulin has been running the site since at least November 2008, mostly through a Ukrainian front company called Cryptoneat. The 30-year-old Vaulin has amassed a net worth of over $54 million, the authorities claim. The DoJ’s complaint notes that Vaulin was listed as the person who registered and renewed domain names used by KAT. His iTunes account had the username “tirm,” which was also the handle of KAT’s owner. The email account associated with his Apple aapl address was also allegedly used in running the site, and the same computer was apparently used to make a purchase using the iTunes account and to log into KAT’s Facebook fb page. For more on file-sharing, watch our video. “In an effort to evade law enforcement, Vaulin allegedly relied on servers located in countries around the world and moved his domains due to repeated seizures and civil lawsuits,” said U.S. assistant attorney general Leslie Caldwell. “His arrest in Poland, however, demonstrates again that cybercriminals can run, but they cannot hide from justice.” The DoJ claims that KAT “stole” more than $1 billion in profits from the U.S. entertainment industry. However, such numbers must always be taken with a pinch of salt—just because someone unlawfully downloaded a film off the Internet for free, that doesn’t mean they would have otherwise paid to see the film legally.