Ethan and Hila Klein, the husband-and-wife team behind the popular H3H3 YouTube channel, appear to have won their legal battle against Matt Hosseinzadeh, a.k.a. Matt Hoss. A New York judge today issued a summary judgement in favor of the Kleins.

Hosseinzadeh sued the Kleins last year after they posted a reaction video mocking him. Hosseinzadeh’s initial suit focused less on the criticism per se, and instead alleged that the Kleins had infringed his copyright by featuring clips of one of his videos in their criticism.

The Kleins defended their use of the footage as fair use, and another YouTube creator, Philip DeFranco, raised more than $170,000 for their legal defense — DeFranco wrote, “If they are bullied and drained of funds because of this ridiculous lawsuit and/or they lose this case it could set a terrible precedent for other creators.”

Ethan Klein offered a similar sentiment in a tweet today describing the outcome as a “huge victory for fair use on YouTube.”

We won the lawsuit. Video coming soon. Huge victory for fair use on YouTube. — Ethan Klein (@h3h3productions) August 23, 2017

The basic legal question was whether the Kleins’ creation of a reaction video that included clips of Hosseinzadeh’s content counts as fair use. In this case, Judge Katherine B. Forrest ruled that it does.

“The key evidence in the record consists of the Klein and Hoss videos themselves,” Forrest writes. “Any review of the Klein video leaves no doubt that it constitutes critical commentary of the Hoss video; there is also no doubt that the Klein video is decidedly not a market substitute for the Hoss video. For these and the other reasons set forth below, defendants’ use of clips from the Hoss video constitutes fair use as a matter of law.”

However, Forrest emphasizes that this isn’t meant to be a blanket defense for all reaction videos. She notes that while some of these videos mix commentary with clips of someone else’s work, “others are more akin to a group viewing session without commentary.”

“Accordingly, the Court is not ruling here that all ‘reaction videos’ constitute fair use,” she says.

Forrest also sides with the Kleins on Hosseinzadeh’s subsequent claim that they defamed him in a video about the lawsuit — she writes, “It is clear that defendants’ comments regarding the lawsuit are either non-actionable opinions or substantially true as a matter of law.”

We’ve reached out to Hosseinzadeh and the Kleins for comment and will update if we hear back. You can also read the judge’s full decision here.

Update, August 24: Here’s a video from H3H3 Productions discussing the decision.

And here’s a comment from Ethan Klein via email:

Extremely relieved. All of our work for the past four years is validated, as there has never been a court opinion about reaction videos. The judge called our method of criticism “quintessential”, which is a huge win for us and the YouTube community. [I’m] extremely grateful to everyone who supported us along the way.

Update, August 26: Tim Bukher, one of Hosseinzadeh’s attorneys, sent us the following statement: