Yahoo is now looking for its fourth chief executive since September, after the company announced Sunday that chief executive Scott Thompson had left.

Holding down the fort at the company now is Ross Levinsohn, the firm’s head of global media, who is serving as interim CEO.

Levinsohn has been with Yahoo since 2010, when former chief executive Carol Bartz appointed him to lead the Yahoo Americas region, which include North, Central and South America.

Before that, Levinsohn was at Fox Interactive Media, where he took the lead on acquiring MySpace for News Corp. in a $580 million deal, All Things Digital reported. He has also worked at AltaVista, CBS Sportsline and HBO.

A seasoned ad executive, Levinsohn was on many analysts’ short lists to lead Yahoo after Bartz was fired in September. Thompson was considered a dark horse candidate, given his lack of media or advertising experience.

On Monday, several analysts (and unnamed sources cited in the Wall Street Journal) said that Levinsohn could be playing for keeps, using his time as interim CEO to audition for the permanent job.

Looking outside the company for Thompson’s replacement wouldn’t help Yahoo’s internal morale, and Levinsohn’s work experience aligns well with the priorities of Yahoo’s new board members, picked by outside investor Third Point. Levinsohn was one of two possible candidates for interim CEO named by the hedge fund in a letter demanding Thompson’s ouster after it learned that Thompson had listed a nonexistent degree in computer science in his biographical information and Yahoo papers.

Levinsohn has a bachelor of arts in communications from American University, according to his Yahoo profile.

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