China rolled out sweeping new rules on Wednesday to rein in aggressive competition in e-commerce, banning major platforms such as Alibaba Group Holding Ltd. (NYSE:BABA) from forcing online merchants into promotions or deep discounts. The regulations, which take effect in February, follow repeated warnings from Beijing to Alibaba, JD.com Inc. (NASDAQ:JD), and Meituan (OTC:MPNGY) to stop pressuring sellers with pricing tactics that regulators say disrupt market order. Authorities also issued separate rule ...