Jobs has struggled with health issues in recent years and the news that he will be taking a leave of absence comes a year and a half after the chief executive received a liver transplant.
In 2004, Jobs announced he had been diagnosed with pancreatic cancer and, that same year, underwent surgery to remove the cancer. He took a medical leave of absence between January and June 2009, with Cook taking over responsibilities for day to day operations. He received a liver transplant in 2009.
When asked about his health at an Apple press conference in July, Jobs replied he was "doing fine" and "feeling great." Yet others have expressed concerns about the CEO's health. The New York Times writes, "In recent months, Mr. Jobs has looked increasingly frail, according to people know have seen him." The lack of a precise end date on Jobs' leave of absence is troubling to some, suggesting the CEO's health issues could be complex and more long term.
Cook, not Jobs, took the stage at a recent press conference in New York at which Verizon announced that it would begin carrying Apple's iPhone. Jobs is expected to appear with news Corp CEO Rupert Murdoch to unveil the media mogul's new iPad newspaper, The Daily.