AOL has not yet made a formal proposal to Yahoo, these people say.

Shares of AOL rose 1.5 percent in afternoon trading, while Yahoo edged down 0.1 percent.

In many respects, the latest discussions derive from plans contemplated in 2008 and 2009 before Time Warner spun off AOL to Time Warner shareholders.

At the time, the media conglomerate had explored the option of breaking apart AOL's two main businesses. The legacy dial-up Internet service would have been spun off or sold to EarthLink or United Online, while the display advertising business would have been merged into Yahoo, the sources said.

More: http://www.reuters.com/article/idUSTRE6B50MF20101206