The company says these users harmed their business.
Twitch Artifact

In March 2019, a bunch of idiots got together and flooded the Artifact section on Twitch with all sorts of random content. This seemed to include everything from multiple hour loops of "Ayaya" to things like showing full copyrighted Hollywood films like Avengers: Endgame, full episodes of various copyrighted television shows like Malcolm in the Middle, a whole lot of uncensored hardcore porn like raw gachi (NSFW if you decide to search for it), to uncensored footage of the Christchurch mosque terror attack, and an assortment of videos full of extreme racism and misogyny.

In other words, it was a real shitshow. For a number of days, it looked like Twitch was fighting a losing battle against the streams that popped up faster than they were taken down. Eventually the mess was cleaned up but the damage was done. Twitch is now going after 100 unnamed defendants in a federal lawsuit that says these users broke its terms of service.

Though Twitch and their moderation team have tools to remove streams that violate their terms of service, the company is going the lawsuit route because what these users did "threatened and continue to threaten Twitch and the safety of the Twitch community."

"Twitch took down the posts and banned the offending accounts, but the offensive video streams quickly reappeared using new accounts. It appears that Defendants use automated methods to create accounts and disseminate offensive material as well as to thwart Twitch’s safety mechanisms."
The lawsuit says that viewers were "understandably upset." Twitch says that they believe some users may have stopped or reduced their use of Twitch as a result of the content that was being streamed in the Artifact section on the site. Though you may be sitting there rolling your eyes at this, there may be some merit to this claim. Twitch had to disable streaming for all newly created accounts for a period of roughly two days while they tried to deal with the mess. They also had to impose two-factor authentication for certain accounts. These actions would have prevented legitimate new users who wanted to stream unable to do so, thus potentially harming Twitch's business.

The lawsuit says that a group of users had mass coordinated the posting of these terms of service breaking streams through a number of different avenues. These include the use of Google, Discord, Weebly, and even a custom website ArtifactStreams.com. That site, by way of a web archive, showed a listing of "active troll Twitch streams" and included links to additional chat rooms used to discuss the troll efforts.

Twitch specifically notes that the site's use of the Twitch logo amounts to copyright infringement. The streams that were embedded on the site committed a breach of contract and fraud.

Twitch is seeking monetary compensation and a permanent legal injunction that will ban the defendants from posting on Twitch in the future. Twitch provided a brief statement to PC Gamer about these events.

"We take these violations extremely seriously," Twitch said in a statement. "We are pursuing litigation to identify these bad actors, and will take all appropriate actions to protect our community."
The Artifact section was selected because the game has been largely dead for a number of weeks now as Valve reworks the game to make it enjoyable for fans. During the height of this event, the troll streams collectively pulled in thousands of viewers. Those who were legitimately trying to stream Artifact had a handful of viewers, at most.

A copy of the lawsuit from Twitch can be seen below.

TWITCH INTERACTIVE, INC. v... by on Scribd