BEIJING • The recent death of a Pinduoduo employee renewed criticism of the long hours commonly practised at China's tech companies, which are already under scrutiny by regulators for anti-competitive business practices. The e-commerce company confirmed yesterday that an employee died after working past midnight last week. That sparked a social media backlash against the company and the relentless working schedules expected of its employees. The so-called 996 office schedule - 9am to 9pm, six days a week, plus overtime - has spurred criticism in previous years following complaints from tech workers and earlier deaths. Still, tech billionaires from Alibaba Group Holding founder Jack Ma to JD.com chief Richard Liu have endorsed the practice as necessary for survival in an intensely competitive industry and the key to accumulating personal wealth. The online criticism adds to the challenges for China's largest tech companies, which spent the past year fending off efforts by the Trump administration to curb their growth while navigating heightened regulatory scrutiny at home. Beijing last November unveiled regulations designed to root out monopolistic practices in the Internet industry...