Frontier Communications, an ISP that serves around 3 million subscribers, has been sued by Warner, Sony, and Universal’s record labels for allegedly not taking action against its users who pirate music (via Ars Technica).

The record labels allege in their complaint (PDF) that not only did Frontier fail to disconnect people who repeatedly pirated, but it even encouraged them by advertising the ability to “download 10 songs in 3.5 seconds” and profited from the result. The labels also allege that Frontier ignored its subscribers’ piracy so it could keep collecting subscription fees, saying that the ISP valued profit over legal responsibility.

Frontier denies wrongdoing, telling The Verge that it has terminated customers when copyright holders complain. The ISP plans to “vigorously defend itself.”

The suit, which was filed in the state of New York, seeks damages from Frontier for its subscribers who have infringed on almost 3,000 copyrighted works after the ISP was repeatedly told about their infringement. A list of pirated songs (PDF) includes Thank U, Next by Ariana Grande, Verge (no relation to this publication) by Owl City, and Rich as Fuck by Lil Wayne featuring 2 Chainz.

The labels are seeking $300,000 per infringement, which would put the ISP on the hook for over $850 million. It’s worth noting that Frontier Communications emerged from chapter 11 bankruptcy last month — having to pay that much in damages wouldn’t be good for any company, but especially not one that’s just getting out of that situation.

Warner, Sony, and Universal have also sued other ISPs like Charter and Cox on similar grounds, winning a $1 billion award from the latter (though that case is still going through the appeals process). And over the past 20 years, the music industry has tried different approaches to curb online piracy, from suing individuals to working with ISPs to set up a strike system.

The approaches haven’t been particularly effective and have largely been abandoned, and it’s hard to foresee the tactic of suing ISPs working to stop music piracy. And, as Ars Technica points out, ISPs being forced to cut off pirates could affect other people living with them as well, denying entire households access to a fundamental part of modern day life.