In an interview with the New York Times Jack Ma revealed his plan to step down as executive chairman of Alibaba -- often referred to as China's Amazon -- on Monday. He co-founded the Chinese internet retailer in 1999 and built it into an empire currently worth $420 billion and making the former English teacher China's richest man worth about $40 billion. According to the paper current CEO Daniel Zhang is a "candidate" to replace Ma, who plans to pursue philanthropy in education. Monday is his 54th birthday, and the Chinese holiday Teacher's Day, making the announcement particularly timely.