Should Yahoo keep or oust Marissa Mayer?

Activists circle Yahoo CEO

As activist investors circle Yahoo, market watchers weigh in on CEO Marissa Mayer's role.

In 3 1/2 years the company went from an Internet pioneer to "the same kind of company that AOL was," Erick Jackson, managing director at SpringOwl Asset Management, told CNBC on Friday in reference to Mayer's performance.

"Other than one hour appearance with Charlie Rose, there's little else to point to," the investor said.

The Yahoo stock was up 3 percent on Friday, but it's down 21 percent in the past year and up 49 percent in the past three years.

Similarly, Larry Haverty, whose firm owns shares of Yahoo, argues that the core business should be sold. The associate portfolio manager at Gabelli Funds told "Closing Bell" that to maximize shareholder value, the company should keep Mayer as CEO.

"I'm afraid if there's disruption in management you're going to lose possibly $400 million/$500 million of EBITDA," he said. "If you put an 8 multiple on that, that's $4 of shareholder value," he continued, adding that investors have suffered mildly, as the stock has been stagnant for 10 years.

Haverty said that his firm invests in value and Yahoo's assets are worth about $53; "there's tremendous value here … we are big believers in Ali Baba."

On the other hand, Jackson argues there have been significant losses during the CEO's tenure, namely lack of innovation in the face of decaying technology.

"When she arrived, Yahoo had more than a billion and a half in EBITDA, now they're at negative EBITDA," he told "Closing Bell." "There are really no Yahoo mobile apps to speak off; more than 80 percent of their revenue still comes from pc and we know that that business is going away."

Conversely, Jackson, whose firm also invests in Yahoo, named potential CEOs that could replace Mayer as the search engine company's chief executive.

"There are a bunch of capable people who could do a much better job than her: Jackie Reses … Ross Levinsohn … Dan Rosensweig … Rich Riley," he suggested. "She talked about a three-year plan … when do you ever hear about that? Somebody getting another three-year plan after failing."

CNBC contacted Mayer's press contact for comment and no response was forthcoming.