Apple chief executive Steve Jobs will not be attending the firm's annual shareholder meeting later this month, the first time he has missed the event.
The annual meetings are traditionally one of the few occasions when shareholders get to question senior executives about the company's performance. Top of the list for many this year will be how much board members knew about the poor state of Jobs's health.
"In the investor's mind, Steve Jobs is the lynchpin to this company's future, and there are unanswered questions," Charles Elson, director of the University of Delaware's John Weinberg Center for Corporate Governance, told Bloomberg.
"His health is not an isolated issue. Unfortunately, it directly relates to investors' confidence in this business, and there has not been enough transparency from the board."
The US Securities and Exchange Commission is reportedly investigating Apple to find out whether the company misled investors over Jobs's health issues, and Apple investors may want to find out more about his decision to step back.
"The company has a responsibility to let public shareholders know that the organisational structure will be sound if Steve Jobs has to leave for any reason," said Apple investor Ryan Jacob, head of the Jacob Internet Fund. He described Apple's record on the disclosure as "poor at best".
Jobs took a six-month leave of absence from Apple in January, after admitting that his health problems were worse than first thought. Since then he has reportedly been considering a liver transplant.
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