Mark Lemley, a professor at Stanford Law School, ​said that Apple’s complaint “has the potential to be a ​very big case” but that some of what Apple ⁠alleges, such as OpenAI’s hiring of hundreds of Apple employees, is not illegal in California, where Silicon Valley sprang up in part thanks to state laws that allow employees leave for a competitor.

“But if Apple’s claims that the employees took confidential documents with them — and that OpenAI is using those documents — are true, that is a problem for OpenAI,” Lemley ​said.