Sensata Technologies Holding plc

Sensata's business is sensing and measurement, yet an intruder moved through its network for nine days before ransomware announced itself by freezing the shipping and production lines. What left was not customer telemetry but the workforce itself: Social Security numbers, passports, and medical records of roughly 15,630 current and former employees, pooled on the same reachable network as the machinery. No group ever claimed it and the files never surfaced on a leak site, which is theft you cannot negotiate back.