Activist investor Carl Icahn has raised his stake in struggling handset maker Motorola to 6.3 percent, up from a reported 5 percent stake. Icahn has mounted a campaign to break Motorola up into four different companies and has also pushed to install four new directors to the board. Earlier this week the board of directors told shareholders to reject Icahn's nominees. Icahn and his associates have spent a total of $2.06 billion to attain the 142.36 million shares that they own.

For more on Icahn's latest moves:
- read this report from The Deal