Apple and OpenAI are escalating their legal fight over allegations that the ChatGPT maker used Apple employees to obtain closely guarded hardware secrets. Why it matters: If the case makes it to the discovery process,

CNBC's MacKenzie Sigalos reports on the first federal court appearance between Apple and OpenAI and why the judge’s handling of discovery could shape Apple’s effort to prove OpenAI used or benefited from allegedly stolen trade secrets.

The lawsuit arrived at the height of Musk’s long-running feud with OpenAI CEO Sam Altman. Earlier this year, a jury sided with OpenAI in a separate lawsuit Musk filed over the company’s shift away from its original nonprofit structure, finding that Musk had waited too long to sue.

A legal battle between Apple and OpenAI took an unusually public turn after OpenAI published private messages.

Apple walked into federal court demanding access to OpenAI's unreleased consumer device, internal communications, and the employees who touched allegedly stolen confidential material. The judge now decides how deep Apple gets to dig before an October 1 showdown.

Apple previously claimed this was "just the tip of the iceberg."

CNBC's MacKenzie Sigalos reports on Monday's Apple vs. OpenAI hearing. Got a confidential news tip? We want to hear from you. Sign up for free newsletters and get more CNBC delivered to your inbox Get this delivered to your inbox,

OpenAI said Apple's lawsuit accusing it of stealing trade secrets was an attempt to make up for its "shortcomings in the market for talent."