A U.S. federal judge has sentenced former software developer Davis Lu to four years in prison and three years of supervised release for sabotaging the computer network of his onetime employer, Ohio-based power-management company Eaton Corp. A jury in Cleveland found Lu, 55, guilty in March of intentionally damaging protected computers after prosecutors showed he had planted a hidden “kill switch” in the firm’s systems. Investigators said Lu embedded malicious Java code—labelled “IsDLEnabledinAD” for “Is Davis Lu enabled in Active Directory”—that created infinite processing loops designed to crash servers and lock out users if his corporate credentials were disabled. The program executed on 9 September 2019, the day Eaton dismissed him, blocking thousands of employees worldwide from logging in and inflicting hundreds of thousands of dollars in losses. Prosecutors presented evidence that Lu deleted co-worker files and searched online for ways to escalate privileges and hide processes before the attack. Acting Assistant Attorney General Matthew Galeotti called the case a reminder of the damage disgruntled insiders can cause, while FBI Cyber Division assistant director Brett Leatherman said the outcome underscores the need for early detection of internal threats.