Bloomberg: Alibaba has bought 33 million shares of Groupon, making it the fourth-largest shareholder in the online deals website that has lost 86 percent of its value since going public more than four years ago. The Chinese e-commerce giant owned 5.6 percent of Groupon as of Dec. 31, according to a regulatory filing. The purchase is said to be part of the Chinese company’s strategy to learn more about the U.S. market as it expands internationally.