Weimob [HKG: 2013] plunged 26% as of 11 a.m. today, after Chinese tech giant Tencent reduced its stake in the third-party service provider for e-commerce merchants on WeChat from 8.4% to 2.9%. Tencent also dumped shares of Ubtech Robotics to bank nearly HKD1.7 billion (USD215 million) combined, according to an HKEX filing.