Artists have been dealt a setback in their copyright fight against generative artificial intelligence (AI) firms after a class-action lawsuit against several of the firms was dismissed by a United States judge, citing a lack of evidence.

In an Oct. 30 order , California District Court Judge William Orrick said the copyright infringement suit against generative AI image service Midjourney, art platform DeviantArt and AI firm Stability AI was “defective in numerous respects,” granting earlier dismissal bids from the firms.

Judge Orrick, however, allowed a copyright infringement claim from one class action member against Stability to go ahead and allowed the class 30 days to attempt to submit an amended suit with more proof.

“Even Stability recognizes that determination of the truth of these allegations — whether copying in violation of the Copyright Act occurred in the context of training Stable Diffusion or occurs when Stable Diffusion is run — cannot be resolved at this juncture,” Orrick wrote.

Highlighted excerpt of Orrick’s conclusive order. Source: CourtListener

The lawsuit was first filed in mid-January and claimed Stability’s AI model, Stable Diffusion, scraped billions of copyrighted images without permission — including those of the artists — to train the software.

DeviantArt also incorporated Stable Diffusion on its site, possibly copying millions of images from there without a license and violating its own terms of service, the suit alleged.

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Orrick said the AI-generated images likely don’t infringe the artists’ copyright, as it’s “not plausible” they’re derived from copyrighted images. He added that he’s “not convinced” unless the class can show the generated images are similar to the artists’ work.

Copyright claims from some class members were dismissed, as their images weren’t registered with the Copyright Office, which is needed for bringing a copyright infringement suit.

Copyright infringement allegations are central to similar legal actions taken against AI firms, such as the Author’s Guild’s class action against OpenAI , Universal Music Group’s suit against Anthropic and Getty Images suits against Stability AI in the U.S. and United Kingdom.

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