Measured in millimeters, the tiny device was designed to allow drones, missiles and rockets to hit targets without satellite guidance. An advanced version was being developed secretly for the U.S. military by a small company and L-3 Communications, a major defense contractor.
On Monday, Sixing Liu, a Chinese citizen who worked at L-3's space and navigation division, was sentenced in federal court to five years and 10 months for taking thousands of files about the device, called a disk resonator gyroscope, and other defense systems to China in violation of a U.S. arms embargo.
The case illustrates what the FBI calls a growing "insider threat" that hasn't drawn as much attention as Chinese cyber-operations. But U.S. authorities warned that this type of espionage can be just as damaging to national security and American business.