Chairman of software giant Microsoft Corp, Bill Gates, sold 1 million shares of common stock, according to a Securities and Exchange Commission filing Friday.

According to a Form 4 filed with the SEC, Gates reported selling the shares on Wednesday for $29.59 to $30.06 per share.

Company insiders file Form 4's with the SEC when they need to report transactions in their companies' shares. Open market purchases and sales must be reported within two business days of the transaction.

Microsoft shares gained 60 cents or 2.04 percent to $29.99.