Steve Jobs' letter of resignation has been added to this story.
CUPERTINO, Calif. (TheStreet) -- Apple (AAPL) CEO Steve Jobs has resigned, according to a statement released after market close by the tech giant, with COO Tim Cook stepping up to take the company's reins.
Jobs submitted his resignation to the Apple board Wednesday, the company explained, and strongly recommended that the board implement its succession plan and name Tim Cook as CEO.
(AAPL) The Apple board subsequently named Cook, previously the iPhone maker's COO, as its new CEO.
"Steve's extraordinary vision and leadership saved Apple and guided it to its position as the world's most innovative and valuable technology company," explained Art Levinson, chairman of Genentech, on behalf of Apple's board, in a statement. "Steve has made countless contributions to Apple's success, and he has attracted and inspired Apple's immensely creative employees and world class executive team."
(AAPL) Jobs, who has been on a medical leave of absence since earlier this year, will serve as chairman of Apple's board, according to the statement. Cook is joining the board as well, effective immediately.
"I have always said if there ever came a day when I could no longer meet my duties and expectations as Apple's CEO, I would be the first to let you know," explained Jobs, in his resignation letter. "Unfortunately, that day has come."
(AAPL) Jobs, however, added that Apple's "brightest and most innovative days" are ahead of it. "I look forward to watching and contributing to its success in a new role."
Apple shares closed Wednesday's regular session at $376.18, up 0.7%. The stock turned lower in extended action, and was last quoted at $356.25, down 5.3%, on volume of more than 500,000.
(AAPL) -- Written by James Rogers in New York.
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