HBO has a bit of a challenge on its hands: every new episode of its mega-hit Game of Thrones is viewed by tens of millions of fans… but a huge percentage of them aren’t actually HBO subscribers. They’re pirating the show, instead. And once again, the show’s most recent season has landed at the top of the “most-torrented” lists for the year.

That calculation comes from TorrentFreak, who would know. For the fifth year running, Game of Thrones is right at the top of the list.

It’s chased by The Walking Dead, which held the number two spot last year also. Newcomer Westworld — another HBO drama — sits in position three, with superhero series The Flash and Arrow once again rounding out the top five.

When Game of Thrones sixth season aired earlier this year, HBO launched a companion effort to beat back the endless hordes of internet pirates who watch the show through less-than-legal means.

The network partnered with anti-piracy agency IP Echelon, which sent thousands of copyright infringement warnings to ISPs on HBO’s behalf. Under the existing “six strikes” system, those ISPs are then supposed to forward those warnings to the infringing customers on their service.

But like a man of the Night’s Watch standing alone against an army of White Walkers, the effort is clearly proving ineffective. HBO’s warnings are either not reaching episode-downloaders, or are falling on deaf ears if they do.

HBO has also stepped up how aggressively it issues file takedown requests to torrent sites, TorrentFreak reported in May, but that, too, seems only barely to be making a dent.

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