not software or software-related, (e.g., third-party digital content sold on the iTunes Store and certain Mac, iPhone and iPod supplies and accessories), the Company recognizes revenue pursuant to various revenue-related GAAP as described below.

The Company recognizes revenue when persuasive evidence of an arrangement exists, delivery has occurred, the sales price is fixed or determinable, and collection is probable. Product is considered delivered to the customer once it has been shipped and title and risk of loss have been transferred. For most of the Company’s product sales, these criteria are met at the time the product is shipped. For online sales to individuals, for some sales to education customers in the U.S., and for certain other sales, the Company defers recognition of revenue until the customer receives the product because the Company retains a portion of the risk of loss on these sales during transit. If at the outset of an arrangement the Company determines the arrangement fee is not, or is presumed not to be, fixed or determinable, revenue is deferred and subsequently recognized as amounts become due and payable and all other criteria for revenue recognition have been met.

For both iPhone and Apple TV, the Company has indicated it may from time-to-time provide future unspecified features and additional software products free of charge to customers. Accordingly, iPhone handsets and Apple TV sales are accounted for under subscription accounting in accordance with GAAP. As such, the revenue and associated cost of sales are deferred at the time of sale, and are both recognized on a straight-line basis over the currently estimated 24-month economic lives of these products, with any loss recognized at the time of sale. If the Company’s estimated economic life of a product accounted for under subscription accounting changes, the future rate at which deferred revenue and deferred costs are recognized in the Company’s results of operations will change. Costs incurred by the Company for engineering, sales, marketing and warranty are expensed as incurred.

The Company records reductions to revenue for estimated commitments related to price protection and for customer incentive programs, including reseller and end-user rebates, and other sales programs and volume-based incentives. For transactions involving price protection, the Company recognizes revenue net of the estimated amount to be refunded, provided the refund amount can be reasonably and reliably estimated and the other conditions for revenue recognition have been met. The Company’s policy requires that, if refunds cannot be reliably estimated, revenue is not recognized until reliable estimates can be made or the price protection lapses. For customer incentive programs, the estimated cost of these programs is recognized at the later of the date at which the Company has sold the product or the date at which the program is offered. The Company also records reductions to revenue for expected future product returns based on the Company’s historical experience. Future market conditions and product transitions may require the Company to increase customer incentive programs and incur