Apple on Friday accused OpenAI of stealing secrets about products still in development, setting up a legal face-off between two of the world’s biggest tech companies.

In a lawsuit filed in U.S. District Court for the Northern District of California, the consumer tech giant said that OpenAI, a leader in artificial intelligence that has a new hardware business, had asked job candidates from Apple to share details about secret projects and to bring device components and prototypes to their interviews.

Apple also accused an OpenAI employee of downloading internal documents from a laptop owned by the iPhone maker.

OpenAI used the confidential information to approach Apple’s manufacturing partners, including asking one partner to demonstrate Apple’s technique for finishing metal on its devices, the lawsuit says.