Sky Atlantic programme, produced by HBO, was downloaded 4.28m times in 2012, according to news website
Game of Thrones was the most-pirated TV show of the year, with a single episode being illegally downloaded by more people than typically watch the hit programme in the US.
HBO's Game of Thrones, which in the UK is aired on Sky Atlantic, knocked off last year's "winner", serial killer show Dexter to be named the most-pirated TV show of 2012.
The annual report, by news site TorrentFreak, found that one episode of Game of Thrones was downloaded 4.28m times.
The estimated US TV audience for an episode of the fantasy swords and sorcery show is 4.2 million, according to the survey.
Among the key reasons given for piracy are limited legal download options and airing delays.
For example, in Australia, where the show is popular, viewers have to wait a week longer than the US audience to see the programme.
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