Three artists have filed a lawsuit that accuses generative artificial intelligence providers Stability AI Ltd., DeviantArt Inc. and Midjourney Inc. of copyright infringement. 

The Verge reported the development today. The lawsuit, which was submitted to the U.S. District Court for the Northern District of California, is structured as a class-action complaint. 

A generative AI model is a neural network that can produce images and other creative works such as essays. Stability AI, DeviantArt and Midjourney, the three companies named in the newly filed copyright lawsuit, offer generative AI services for producing images. The complaint alleges that companies’ services make unauthorized use of existing copyrighted images.

The first focus of the lawsuit is a generative AI model called Stable Diffusion. Released by Stability AI last August, the model is available under an open-source license. It can generate images based on text prompts provided by users. 

Two months after releasing Stable Diffusion, the London-based startup raised a $101 million funding round. At the time of the investment, Stability AI disclosed that the open-source version of Stable Diffusion had been downloaded more than 200,000 times. The startup also offers a cloud version of the neural network that it says has an installed base of more than 1 million users. 

During the development of Stable Diffusion, Stability AI trained the neural network on a large dataset of images. That dataset “con­tains unau­tho­rized copies of mil­lions — and pos­si­bly bil­lions — of copy­righted images,” Matthew Butterick, an attorney for the plaintiffs who filed the copyright lawsuit, charged in a blog post Friday. “These copies were made with­out the knowl­edge or con­sent of the artists.”

Because it’s available under an open-source license, Stable Diffusion can be used by developers to build custom AI applications. DeviantArt, the second company named in the class-action lawsuit, used the neural network to build an image generation service called DreamUp. It also operates a popular art website.

“Rather than stand up for its com­mu­nity of artists by pro­tect­ing them against AI train­ing, DeviantArt instead chose to release DreamUp, a paid app built around Sta­ble Dif­fu­sion,” Butterick wrote. “In turn, a flood of AI-gen­er­ated art has inun­dated DeviantArt, crowd­ing out human artists.”

The third organization named in the lawsuit is Midjourney. The San Francisco-based firm provides a generative AI tool that, similarly to Stable Diffusion, can generate images based on text prompts. According to Butterick, the company has stated that its AI is trained on “a big scrape of the inter­net.”

Butterick filed the lawsuit on behalf of the plaintiffs together with San Francisco-based Joseph Saveri Law Firm LLP. Last November, Butterick and the firm filed a similar suit against Microsoft Corp. and OpenAI LLC. The latter complaint alleges that the companies’ AI-powered GitHub Copilot programming assist makes unauthorized use of open-source software code.

Photo: Stability AI