Yahoo Inc. ended the brief tenure of its latest chief executive after a flap over a flawed biography of him in a regulatory filing spiraled into a major embarrassment for the ailing Internet company and a big victory for an activist investor.

Scott Thompson, whom Yahoo hired as CEO in January, agreed to resign over the weekend after the company's board obtained evidence that contradicted his claim of innocence about his misstated academic record, people familiar with the matter said.

In particular, an executive-search firm provided Yahoo with information that appeared to show Mr. Thompson years ago had knowingly claimed to have a computer-science degree that he, in fact, didn't have.

Yahoo said it named Ross Levinsohn, the executive in charge of its media websites, as interim CEO. Mr. Levinsohn's appointment could be made permanent, one person said.

In addition, director Fred Amoroso was named nonexecutive chairman, succeeding Chairman Roy Bostock, who had been slated to leave this summer.

Mr. Thompson, who had told Yahoo colleagues that he wasn't responsible for the misstatements about his academic record, became the fourth Yahoo CEO to step down in the past five years. He couldn't be reached for comment Sunday.

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