Courtesy of Creative Commons

"The time has come for me to pursue other interests outside Yahoo," Yang said in a statement.

Yang, who saw the company from its inception and through its heights atop the late-90s dotcom bubble, has been embattled recently for a string of controversial decisions. As CEO he notoriously blocked a 2008 takeover attempt by Microsoft that many insiders saw as the best option of the flagging company.

In the past decade, Yahoo has lost its status to Google as a top search engine, and both Google and Facebook have come to dominate the online advertising webspace.

Yahoo has undergone a series of management changes recently, including hiring a new CEO two weeks ago after the board booted the previous chief four months earlier.

Yahoo shares closed up 3 percent by the end of the day, closing at $15.95.