Microsoft Chief Executive Officer Steve Ballmer sold over 49 million of his Microsoft shares at the end of last week; shares worth a total of $1.335 billion (£826 million). This leaves him with over 358 million shares in Microsoft, which represents around 4.2% of the company.
In a statement, Microsoft said Mr Ballmer's share sale was "to gain financial diversification and to assist in tax planning" and mentioned that he could sell another 25 million shares before the end of 2010.
Steve Ballmer said "Even though this is a personal financial matter, I want to be clear about this to avoid any confusion. I am excited about our new products and the potential for our technology to change people's lives, and I remain fully committed to Microsoft and its success."