While plenty of people were legally watching the Game of Thrones season premiere on Sunday, some of those viewers were also using their accounts on Periscope, the Twitter-owned live-streaming service, to illegally re-broadcast the show to their online pals. In response, HBO has sent takedown notices and these Periscope users may have their accounts suspended.

“We are aware of Periscope and have sent takedown notices,” an HBO rep told the Hollywood Reporter.

Periscope’s Terms of Service make it clear that copyright infringement is not allowed.

“Twitter, Inc. respects the intellectual property rights of others and expects users of Periscope Services to do the same,” reads the TOS, which explain that authorized takedown requests will be honored and that “In appropriate circumstances, Periscope will also terminate a user’s account if the user is determined to be a repeat infringer.”

However — and this appears to be the big sticking point for HBO and others — there is no proactive method for identifying infringing behavior. Just like many social media platforms, Periscope relies on users and copyright holders reporting accounts that are using the service to stream out movies, TV shows, concerts, and sporting events without permission.

In its statement to HR, HBO indicates that Periscope should be doing more to preempt this sort of behavior rather than waiting for users to rat out other users.

“In general, we feel developers should have tools which proactively prevent mass copyright infringement from occurring on their apps and not be solely reliant upon notifications,” explained the HBO rep.

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