Runway published Stable Diffusion 1.5, a new version of the image model, on Hugging Face. The same day, Stability AI sent Hugging Face a takedown notice calling it a leak of its intellectual property. Runway answered on the model's own page that the release was made under the Creative ML OpenRAIL-M licence and infringed nothing, and thanked Stability AI for the compute it had donated to retrain the original model. Patrick Esser, who wrote the model, was a Runway researcher. The notice was withdrawn soon afterwards and 1.5 stayed up. The arrangement under which the two had published together in August had become, within two months, an argument about who was allowed to put the weights out.