Hayes will remain on the Yahoo board through the shareholder meeting.
“While I have tremendous confidence in the continued progress and success of Yahoo, I am unable to bring the time and focus I'd like to Yahoo, given my broad executive responsibilities at American Express," said Hayes in a Yahoo release issued after the market close.
Hayes has served as CMO of American Express since 2003, and previously was EVP of the company. Prior to joining AmEx, he was president of Lowe & Partners, a brand and advertising firm, where he focused on the development of global campaigns and product marketing for corporate brands. He remains a director of Keurig Green Mountain.
“John brought enthusiasm, expertise and energy to the Yahoo board. His insights into how to nurture our brand and implement our strategy have been invaluable,” stated Yahoo CEO Marissa Mayer.
Yahoo separately on Thursday released its semiannual transparency report, indicating a significant decline in the number of government requests for data about its users during the second half of 2013 compared to the first half.
Yahoo said it had received 21,425 requests from 17 countries for information on 32,493 accounts from July through December. U.S. users made up about a third of the total, which did not include requests made under national security and the Foreign Intelligence Surveillance Act, or FISA.
In the prior six months, Yahoo was sent 29,740 requests for data on 62,775 accounts. Those totals, however, did include national security and FISA requests, which ranged from 0 to 3,000 and spanned 30,000 to 33,000 accounts.