HBO has in the past taken a rather nonchalant approach to piracy, even at times taking the surprisingly refreshing viewpoint that millions of illegal downloads can be viewed as a "compliment of sorts" and that it comes with the territory of "having a wildly successful show on a subscription network." The thing is, if you poke the bear too many times, it's going to react, so nobody should be shocked that HBO is sending out DMCA notices to Game of Thrones pirates.
On the surface, it appears HBO is fed up with all the illegal downloads. Season 5 of Game of Thrones saw its first episode downloaded more than 100,000 times in just three hours, which ballooned to over a million within 18 hours. That's par for course, but when it happens season after season, perhaps it can wear down on a network.
According to TorrentFreak, HBO has been blitzing pirates with DMCA takedown notices with the help of its anti-piracy partner IP-Echelon, which has been contacting Internet Service Providers to relay alerts to IPs of infringing users. ISPs are asked to contact the subscriber in question and take steps to stop the illegal behavior, and have been urged to disconnect accounts of repeat abusers.
Why the change of heart from HBO? It's probably not one. TorrentFreak says there's not a whole lot HBO can do with DMCA notices, as it doesn't know the identity of the people it's accusing of pirating Game of Thrones, and therefore no legal strings exist.
In other words, this is a bit of a scare tactic. Considering that millions of illegal downloads are occurring, it's understandable that HBO would at least take some type of measure to try and reduce piracy. At the same time, as noted in the past by HBO's programming president Michael Lombardo, all these illegal downloads don't seem to be negatively impacting DVD sales.