Apple has delayed its annual financial report due to an investigation into stock options.

In a filing with the Securities and Exchange Commission (SEC) on Friday, the company said it was unable to meet the 14 December deadline, giving the stock grants as the reason. It also said it would need to restate its historical financial statements.

Apple said it is in the process of finalising the amount of charges, the resulting tax and which periods would need to be restated as a result of its independent investigation. The stock option irregularities were first reported by the company in June.