Alibaba Group expanded its share buyback program from $15 billion to $25 billion, for the second time in a year. The largest buyback in Alibaba history will run for two years through March 2024, the company said in a statement on Tuesday, adding the board had authorized the program. As of March 18, the company has purchased 56.2 million American depositary shares (ADS) under the previously announced buyback program for $9.2 billion. "The upsized share buyback underscores our confidence in Alibaba's long-term, sustainable growth potential and value creation," said Toby Xu, Alibaba Group's deputy chief financial officer, in a statement.