This excerpt taken from the AAPL DEF 14A filed Jan 12, 2010.
As is customary in incentive plans of this nature, each share limit and the number and kind of shares available under the 2003 Plan and any outstanding awards, as well as the exercise or purchase prices of awards, and performance targets under certain types of performance-based awards, are subject to adjustment in the event of certain reorganizations, mergers, combinations, recapitalizations, stock splits, stock dividends, or other similar events that change the number or kind of shares outstanding, and extraordinary dividends or distributions of property to the shareholders.
This excerpt taken from the AAPL DEF 14A filed Apr 16, 2007.
Adjustments. In the event any change is made in the Companys capitalization during an offering period, such as a stock split or stock dividend, that results in an increase or decrease in the number of shares of Common Stock outstanding without receipt of consideration by the Company, appropriate adjustments will be made to the purchase price and to the number of shares subject to stock purchase under the Purchase Plan, to the number of shares authorized for issuance under the Purchase Plan, and to the maximum number of shares that may be purchased by an employee during any six-month purchase period.