HONG KONG -- On a chilly night in late February, 24-year-old tech worker Emma decided to kill herself.

Legal experts say a growing number of China's leading tech companies are using noncompete agreements to retain even junior talent as the U.S.-China tech war heats up. (Illustration by Yoshiko Kawano)
From Tencent to Pinduoduo, companies use surveillance and lawsuits to retain staff as competition ramps up