More than 10,500 creative professionals, including Thom Yorke from Radiohead, actress Julianne Moore, and Nobel Prize-winning novelist Kazuo Ishiguro, have signed an open letter condemning “unlicensed use of creative works” to develop artificial intelligence systems such as OpenAI’s ChatGPT.

Use of creative work without a license for AI development is “a major, unjust threat to the livelihoods of the people behind those works, and must not be permitted,” the brief, 29-word letter says.

OpenAI and other tech companies need text, images, video and other material to train the algorithms that power chatbots and other AI systems. That data has often been scraped from the internet without consent, compensation or credit.

Tech companies have argued this practice is protected as “fair use” under copyright law, but content owners and publishers have increasingly fought back. They have asserted in lawsuits and pleas to regulators that AI developers using their work have illegally infringed on their copyright protections.

“This question of creators’ rights is incredibly pressing,” said Ed Newton-Rex, a former AI executive and music composer who helped organise the letter, released on Wednesday, and is now chief executive of nonprofit Fairly Trained, which certifies tech companies for data practices that support creators’ rights. “Right now, it’s important to send a message.”