Federal prosecutors have charged a former Apple employee with stealing trade secrets from Apple's self-driving car project and attempting to take them with him to a new job at a Chinese startup. Xiaolang Zhang had worked on Apple's self-driving car project since 2015. According to the FBI, he "designed and tested circuit boards to analyze sensor data." But at the end of April, he informed his supervisor that he was quitting, moving to China to be closer to his mother, and that he would be taking a job at a Chinese startup.

The supervisor thought Zhang had been "evasive" during this conversation, so he asked Apple's security team to look into the situation. They discovered that Zhang's activity on the Apple network had "increased exponentially" in the days before Zhang announced his departure.

According to the FBI, Zhang downloaded numerous documents from Apple's network and transferred them to his wife's personal laptop. The information Zhang took was "largely technical in nature, including engineering schematics, technical reference materials, and technical reports."

Authorities also say Zhang "admitted to removing items" from Apple's campus, including "two circuit boards and a Linux server from the hardware lab."

The criminal complaint against Zhang includes an interesting tidbit: Apple has as many as 5,000 people involved in the self-driving car project. Apple has a compartmentalized culture where employees are only read into confidential projects on a need-to-know basis. Yet the FBI says that "approximately 5,000 of Apple's over 135,000 full time employees" have been granted clearance to receive information about Apple's project to "develop software and hardware for use in autonomous vehicles."

Of course, not all of those 5,000 people are necessarily working on the project full time. But the FBI also says that 2,700 Apple employees have access to one or more confidential databases related to Apple's self-driving car project.

Authorities arrested Zhang at the San Jose airport on Saturday after he purchased a last-minute plane ticket to China. He faces charges in federal court in the Northern District of California.