#5 John T. Chambers

Company: Cisco Systems

Country: United States

Tenure: 1995 – present

Chambers joined Cisco in 1991 as senior vice president, Worldwide Sales and Operations. Since January 1995, when he assumed the role of CEO, the company has grown from $70 million in annual revenues to its current run-rate of approximately $46 billion. In November 2006, he was named Chairman of the Board, in addition to his CEO role.

#4 Margaret C. Whitman

Company: eBay

Country: United States

Tenure: 1998 – 2008

Whitman served as president and chief executive officer of eBay from 1998 to 2008. During her ten years with the company, she oversaw expansion from 30 employees and $4 million in annual revenue to more than 15,000 employees and $8 billion in annual revenue. She resigned from the company in 2007 but stayed on the board for another year as an advisor to the new CEO.

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