So popular are those smutty scenes that viewers are uploading them to PornHub, an adult website that claims to be the world’s biggest. The adult film industry, meanwhile, has been cranking out dozens of Game of Thrones “parodies” featuring actors that look like characters on the show.

All of this has reached a point that HBO (TWX) , which produces Game of Thrones, has taken notice. Unsurprisingly, the studio is not pleased about its popularity on PornHub.

“HBO is aware of the issue and is in the process of getting material taken down fromPornHub,” said HBO in a statement.

While a BBC report stated that HBO is “taking action againstPornHub for breach of copyright,” a studio spokesperson said it has not filed any lawsuit.

PornHub, meanwhile, said by email that it respects copyright and responds immediately to takedown requests. But at the same time, the company has published statistics attesting to the popularity of Game of Thrones among its users.

These stats include data about the most popular character searches (the “Mother of Dragons” Daenerys is number one, followed by female characters Margaery, Shae, and Cersei) as well as evidence the porn site’s traffic drops by 4% when Game of Thrones is on TV.

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While some might see PornHub’s data as promoting viewers to seek out unlicensed HBO content, it’s unlikely the site faces serious legal risk.

The reason is so-called “safe harbor” laws, which protects all manner of websites—from YouTube to Facebook to PornHub—from liability for content uploaded by their users. So long as PornHub obeys takedown requests, it is shielded from copyright infringement.

According to John Bergmayer, a copyright attorney with Public Knowledge, the decision to publish the Game of Thrones data does not meanPornHub forfeits the safe harbors, or commits so-called “secondary infringement”—an offense that studios use to go after pirate websites.

As for the Game of Thrones users who upload the scenes, Bergmayer says it’s unlikely they could claim fair use, a legal rule that gives people the right to use copyrighted materials in certain situations.

“It doesn’t really appear they’re doing much in the way of commentary or criticism or cultural work—they’re just being perverts,” he said, adding that he was not familiar with the videos in question.

On the other hand, said Bergmayer, those who upload can always point to the short length of a clip to argue for fair use.

But most interesting question could be whether the adult-themed Game of Thrones parodies count as fair use. While the law typically provides very robust protection to parody, HBO could argue sex scenes based on its characters are not parody at all.

PornHub said those who post videos on its site could advocate fair use cases themselves by filing a so-called “counter-notice” to restore a video that has been taken down. HBO did not respond to questions about its policy on parody.