China's Alibaba is pressuring merchants to offer rock-bottom prices on its marketplaces in this year's Singles Day extravaganza, three industry sources said, as the e-commerce company seeks to boost sales and stem a drop in market share. The sources, who help dozens of brands operate their stores on Alibaba’s platforms, said they were told to offer the best price of the year on Tmall or Taobao for the blockbuster shopping event, or risk losing the traffic and support given to event participants. While Alibaba has announced that it will offer 80 million products at their lowest prices this year during Singles Day, which began in late October and stretches till Nov. 11, the push to get merchants to toe its line is unusual for the company, they said.