Up until his departure from Microsoft last December, Sinofsky was president of the Windows division, where he drove the development of Windows 7 and Windows 8 operating systems. His departure was viewed by many as a result of an internal power struggle between Sinofsky and Microsoft CEO Steve Ballmer. In a recent SEC filing by Microsoft, it was agreed between the company and Sinofsky that he would have a non-compete contract for a year in exchange for an estimated US$14m worth of stock.