The hit HBO drama Game of Thrones topped blog TorrentFreak's study of the most pirated shows of 2012, which skewed heavily toward pay cable and genre shows, The Hollywood Reporter said.

TorrentFreak reports that the top Game of Thrones episode was illegally downloaded 4.28 million times in 2012, though more than 90 percent of the downloads occur in the first week of a show's first-run airing.

For comparison, the June 3 season two finale drew 4.2 million viewers in the U.S. during its first-run airing on HBO, a ratings record for the show.

The second-most pirated show was Showtime's Dexter with 3.85 million first-week downloads, topping its legal U.S. audience of 2.75 million.

The top broadcast network show on the list is CBS' comedy The Big Bang Theory with 3.2 million illegal downloads. CBS also had the second-most pirated network show with No. 4's How I Met Your Mother (2.96 million downloads).

Breaking Bad, with 2.58 million downloads (vs. 2.98 million U.S. viewers) was the most pirated basic cable show. Rounding out the top 10 are The Walking Dead (AMC), Homeland (Showtime), House (Fox), Fringe (Fox) and Revolution (NBC).