The search process is still in the early stages and the board isn't close to making a decision, said the people. The board retained Heidrick & Struggles to look at internal and external candidates after Ballmer, who has led the world's largest software maker since 2000, said in August that he plans to retire within a year.
The board's task to find a new CEO is urgent as Microsoft undergoes a strategic change and confronts an altered technology landscape. While it once rode a wave of growth in the personal- computer industry with its Windows operating system, the company has been retooling itself more recently as consumers gravitate to mobile devices such as smartphones and tablets.
Ballmer has overhauled Microsoft's management and strategy to accelerate development of hardware and services, and last month agreed to buy Nokia's handset unit. Microsoft also has sought to head off shareholder dissent by reaching a cooperation agreement with ValueAct Holdings LP, which would let the activist investor claim a board seat starting next year.
Tony Imperati, a spokesman for Redmond, Wash.-based Microsoft, declined to comment on specific candidates or to make Bates available.
Maritz didn't respond to a message for comment. Elop didn't respond to a request for comment.
Ford Motor's Executive Chairman Bill Ford on Tuesday touted the abilities of the company's next generation of executives, while emphasizing the No. 2 U.S. automaker's plan for Mulally to remain CEO. Mulally and Chief Operating Officer Mark Fields, the top candidate to next lead the Dearborn, Mich.-based carmaker, last month reiterated a plan announced in November for the CEO to remain through at least 2014.
Jay Cooney, a spokesman for Ford, said Mulally was unavailable. Mulally hasn't responded to multiple requests for comment on his potential candidacy for the Microsoft job in the past week.
"Alan remains absolutely focused on continuing to make progress on our One Ford plan," Cooney said in an e-mail. "We do not engage in speculation."
Technology blog AllThingsD reported Mulally's candidacy for Microsoft's top job last week.
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