CUPERTINO, Calif. ( TheStreet) -- Apple ( AAPL) CEO Steve Jobs said Monday that he will take a medical leave of absence.

In a statement posted on Apple's Web site, Jobs said the tech giant's board had granted him the leave "so I can focus on my health."

During his leave, Jobs will remain the company's CEO and be involved in major strategic decisions, but Tim Cook, Apple's chief operating officer, will be responsible for the company's day-to-day operations.

The statement did not specify how long Jobs expected to be away or what his health issue was.

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Apple's CEO and co-founder has battled serious illness before. In 2004 he took time off to undergo treatment for pancreatic cancer. And in 2009 he took a six-month leave of absence during which he received a liver transplant. Tim Cook served as acting CEO during both absences.

Apple CEO Steve Jobs gesturing in Palo Alto, Calif. just after he underwent cancer surgery in July, 2004.

Jobs' health has long been the subject of media and investor speculation. Following his battle with pancreatic cancer, observers often scrutinized his appearance during keynote speeches, wondering whether his gauntness or level of energy indicated he was sick again.

Jobs has come under fire for not being more forthcoming about his health. Critics have contended that because he is such an aggressive, hands-on manager and engineered Apple's runaway success in recent years, it is crucial for shareholders to be better apprised of his health problems.

Shares of Apple closed Friday at $348.48. The company plans to report earnings after the bell Tuesday.
This article was written by a staff member of TheStreet.

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