Ira Rothken (left) has been representing Kim Dotcom since 2012. (credit: Ira Rothken) Just over a week ago, federal authorities announced the arrest of a Ukrainian man that they say is the mastermind of KickassTorrents (KAT), which, until recently, was the world’s largest BitTorrent search site. Now, the suspect, Artem Vaulin, 30, has retained Ira Rothken, the California lawyer who has successfully kept Kim Dotcom out of custody in New Zealand since 2012. Rothken serves as Dotcom's lead global counsel—his client still faces criminal charges over alleged massive copyright infringement on his now-shuttered site, Megaupload.