Apple Computer Inc. (AAPL) said Friday it will delay filing its latest quarterly report and expects to make "significant changes" to results for the period because of irregularities related to past stock-option grants.

In a filing with the Securities and Exchange Commission on Friday, Apple said it expects to have to restate past results in order to take non-cash charges for compensation costs related to stock option granting practices.

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Apple said it hasn't yet determined the amount of such charges, the resulting tax and accounting impact, or which periods may require restatement. However, the company said it expects to make "significant changes" to results for its fiscal third quarter, including significant increases in revenue and expenses.

On June 29, the company announced that an internal investigation discovered irregularities related to the issuance of certain stock option grants made between 1997 and 2001. A special committee of Apples outside directors hired independent counsel to perform an investigation, and the company informed the SEC of its plans.

As a result of the ongoing investigation, Apple was unable to file its quarterly report for the third quarter ended July 1 by the required date.

Apple shares fell 78 cents, or 1.2 percent, in pre-market trading on the INET electronic exchange.

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