Apple said in a filing with the U.S. Securities and Exchange Commission on Thursday that Cook had asked to be excluded from a recently instituted company program through which employees can accumulate dividends on their restricted stock units that are still vesting.

Asked why Cook was doing this, Apple declined to comment beyond the filing.

Cook, who took over as chief executive from late co-founder Steve Jobs in August, has 1.125 million outstanding restricted Apple shares that are vesting over the next 10 years.

In January, Apple's board granted Cook 1 million restricted stock units (RSUs) for running the company during Jobs' medical leaves and as a retention tool. Half of those units are due to vest in 2016 and the remainder are due to vest in 2021.

Apple said in March that it would pay a cash dividend of $2.65 per share to its shareholders.

(Reporting By Poornima Gupta)

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