Jack Ma, the billionaire who ushered e-commerce into China, is officially stepping down as Alibaba’s executive chairman on Tuesday. He’s celebrating his retirement with a big bash at an Olympic-sized stadium in the company’s hometown of Hangzhou. After two decades building Alibaba into a $460 billion business, Ma is now pivoting full time to philanthropy. He started the Jack Ma Foundation in 2014, and has cited the Bill and Melinda Gates Foundation as an inspiration for his charitable endeavors. “Jack has been signaling for some time his interests in philanthropy, environment, women’s empowerment, education and development,” said Duncan Clark, the author of “Alibaba: The House That Jack Ma Built.” Read more at CNN Business.