Note 1. Organization and Summary of Significant Accounting Policies

Western Digital Corporation (the “Company” or “Western Digital”) is an industry-leading developer and manufacturer of storage solutions that enable people to create, manage, experience and preserve digital content. The Company designs and makes storage devices and home entertainment products under the HGST, WD and G-Technology brands. The Company’s principal products today are hard drives that use one or more rotating magnetic disks (“magnetic media”) to store and allow fast access to data. Hard drives are today’s primary storage medium for digital content. The Company operates its global business through two independent subsidiaries due to regulatory requirements—HGST and WD, both long-time innovators in the storage industry.

The Company has prepared its consolidated financial statements in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and has adopted accounting policies and practices which are generally accepted in the industry in which it operates. The Company’s significant accounting policies are summarized below.

Fiscal Year

The Company has a 52 or 53-week fiscal year. The 2013, 2012 and 2011 fiscal years which ended on June 28, 2013, June 29, 2012 and July 1, 2011, respectively, consisted of 52 weeks each.

Basis of Presentation

The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. In fiscal 2013, the accounts for all foreign subsidiaries have been remeasured using the U.S. dollar as the functional currency. In fiscal 2012, the accounts for all foreign subsidiaries, except for one Japanese subsidiary in which Yen was the functional currency, have been remeasured using the U.S. dollar as the functional currency. Gains or losses resulting from remeasurement or translation of these accounts from local currencies into U.S. dollars were immaterial to the consolidated financial statements.

On March 8, 2012 (“Closing Date”), the Company completed its acquisition (“the Acquisition”) of all of the issued and paid-up share capital of Viviti Technologies Ltd., known until shortly before the Acquisition as Hitachi Global Storage Technologies Holdings Pte. Ltd. (“HGST”) from Hitachi, Ltd. (“Hitachi”). The acquisition is further described in Note 14. The results of operations of HGST since the date of Acquisition are included in the consolidated financial statements.

Cash and Cash Equivalents

The Company’s cash equivalents represent highly liquid investments in money market funds, which are invested in U.S. Treasury securities, U.S. Treasury bills and U.S. Government agency securities with original maturities when purchased of three months or less.

Investments

The Company’s investments consist of auction-rate securities, which are primarily backed by insurance products with original maturities greater than three months. The Company has classified these investments as available-for-sale securities and they are carried at fair value within other non-current assets in the consolidated balance sheets. In addition, the Company enters into certain strategic investments for the promotion of business and strategic objectives. These strategic investments are recorded at cost within other non-current assets in the consolidated balance sheets and are periodically analyzed to determine whether or not there are indicators of impairment.

Fair Value of Financial Instruments

The carrying amounts of cash equivalents, accounts receivable, investments, accounts payable and accrued expenses approximate fair value for all periods presented because of the short-term maturity of these assets and liabilities or, in the case of investments, these are recorded using appropriate market information. The carrying amount of debt approximates fair value because of its variable interest rate.

Concentration of Credit Risk

The Company sells its products to computer manufacturers, resellers and retailers throughout the world. The Company performs ongoing credit evaluations of its customers’ financial condition and generally requires no collateral. The Company maintains allowances for potential credit losses, and such losses have historically been within management’s expectations. At any given point in time, the total amount outstanding from any one of a number of its customers may be individually significant to the Company’s financial results. At both June 28, 2013 and June 29, 2012, the Company had reserves for potential credit losses of $9 million, and net accounts receivable of $1.8 billion and $2.4 billion at each date, respectively.

The Company also has cash equivalent and investment policies that limit the amount of credit exposure to any one financial institution or investment instrument and requires that investments be made only with financial institutions or in investment instruments evaluated as highly credit-worthy.

Inventories

The Company values inventories at the lower of cost (first-in, first out and weighted average methods) or net realizable value. The first-in, first-out (“FIFO”) method is used to value the cost of the majority of the Company’s inventories, while the weighted-average method is used to value precious metal inventories. Weighted-average cost is calculated based upon the cost of precious metals at the time they are received by the Company. The Company has determined that it is not practicable to assign specific costs to individual units of precious metals and, as such, precious metals are relieved from inventory based on the weighted-average cost of the inventory at the time the inventory is used in production. The weighted average method of valuing precious metals does not materially differ from a FIFO method. As of June 28, 2013 and June 29, 2012, 91% and 89%, respectively, of the inventory was valued using the FIFO method with the remainder valued using the weighted average method. Inventory write-downs are recorded for the valuation of inventory at the lower of cost or net realizable value by analyzing market conditions and estimates of future sales prices as compared to inventory costs and inventory balances.

The Company evaluates inventory balances for excess quantities and obsolescence on a regular basis by analyzing estimated demand, inventory on hand, sales levels and other information, and reduces inventory balances to net realizable value for excess and obsolete inventory based on this analysis. Unanticipated changes in technology or customer demand could result in a decrease in demand for one or more of the Company’s products, which may require a write down of inventory that could materially affect operating results.

Property, Plant and Equipment

The cost of property, plant and equipment is depreciated over the estimated useful lives of the respective assets. The Company’s buildings are depreciated over periods ranging from fifteen to thirty years. The majority of the Company’s equipment is depreciated over periods of two to seven years. Depreciation is computed on a straight-line basis. Leasehold improvements are amortized over the lesser of the estimated useful lives of the assets or the related lease terms.

Goodwill and Other Long-Lived Assets

The fair value of assets acquired and liabilities assumed in a business acquisition are recognized at the acquisition date, with amounts exceeding the fair values being recognized as goodwill. Goodwill is not amortized. Instead, it is tested for impairment on an annual basis or more frequently whenever events or changes in circumstances indicate that goodwill may be impaired. During 2013, the Company changed the date of its annual impairment test from the last day of May to the first day of its fiscal fourth quarter. The Company believes changing the test date to the first day of its fiscal fourth quarter is preferable as it should allow the Company additional time to complete the impairment test.

The Company first uses qualitative factors to determine whether goodwill is more likely than not impaired. If the Company concludes from the qualitative assessment that goodwill is more likely than not impaired, it follows a two-step approach to quantify the impairment.

The Company is required to use judgment when applying the goodwill impairment test, including the identification of reporting units, assignment of assets and liabilities to reporting units, assignment of goodwill to reporting units, and determination of the fair value of each reporting unit. In addition, the estimates used to determine the fair value of each reporting unit may change based on results of operations, macroeconomic conditions or other factors. Changes in these estimates could materially affect the Company’s assessment of the fair value and goodwill impairment for each reporting unit. The Company did not record any impairment of goodwill during 2013, 2012, or 2011.

Other intangible assets consist primarily of technology acquired in business combinations and in-process research and development. In-process research and development is not amortized. Instead, it is instead tested for impairment on an annual basis or more frequently whenever events or changes in circumstances indicate that it may be impaired. Acquired intangibles are amortized on a straight-line basis over their respective estimated useful lives. Long-lived assets are tested for recoverability whenever events or changes in circumstances indicate that their carrying amounts may not be recoverable. If impairment is indicated, the impairment is measured as the amount by which the carrying amount of the assets exceeds the fair value of the assets. The Company recorded impairments to certain long-lived assets in 2013 and 2012. See Notes 15 and 16. The Company did not record any impairment to long-lived assets in 2011.

Revenue and Accounts Receivable

Revenue is recognized when the title and risk of loss have passed to the customer, there is persuasive evidence of an arrangement, delivery has occurred, or services have been rendered, the sales price is fixed or determinable and collectability is reasonably assured. The Company establishes provisions against revenue and cost of revenue for estimated sales returns in the same period that the related revenue is recognized based on existing product return notifications. If actual sales returns exceed expectations, an increase in the sales return accrual would be required, which could materially affect operating results.

In accordance with standard industry practice, the Company provides distributors and retailers (collectively referred to as “resellers”) with limited price protection for inventories held by resellers at the time of published list price reductions, and the Company provides resellers and OEMs with other sales incentive programs. At the time the Company recognizes revenue to resellers and OEMs, a reduction of revenue is recorded for estimated price protection until the resellers sell such inventory to their customers and the Company also records a reduction of revenue for the other programs in effect. The Company bases these adjustments on several factors including anticipated price decreases during the reseller holding period, reseller’s sell-through and inventory levels, estimated amounts to be reimbursed to qualifying customers, historical pricing information and customer claim processing. If customer demand for hard drives or market conditions differ from the Company’s expectations, the Company’s operating results could be materially affected. The Company also has programs under which it reimburses qualified distributors and retailers for certain marketing expenditures, which are recorded as a reduction of revenue. Sales incentive and marketing programs are recorded as a reduction of revenue.

The Company records an allowance for doubtful accounts by analyzing specific customer accounts and assessing the risk of loss based on insolvency, disputes or other collection issues. In addition, the Company routinely analyzes the different receivable aging categories and establishes reserves based on a combination of past due receivables and expected future losses based primarily on its historical levels of bad debt losses. If the financial condition of a significant customer deteriorates resulting in its inability to pay its accounts when due, or if the Company’s overall loss history changes significantly, an adjustment in the Company’s allowance for doubtful accounts would be required, which could materially affect operating results.

Warranty

The Company records an accrual for estimated warranty costs when revenue is recognized. The Company generally warrants its products for a period of one to five years. The warranty provision considers estimated product failure rates and trends, estimated replacement costs, estimated repair costs which include scrap costs, and estimated costs for customer compensatory claims related to product quality issues, if any. A statistical warranty tracking model is used to help prepare estimates and assist the Company in exercising judgment in determining the underlying estimates. The statistical tracking model captures specific detail on hard drive reliability, such as factory test data, historical field return rates, and costs to repair by product type. Management’s judgment is subject to a greater degree of subjectivity with respect to newly introduced products because of limited field experience with those products upon which to base warranty estimates. Management reviews the warranty accrual quarterly for products shipped in prior periods and which are still under warranty. Any changes in the estimates underlying the accrual may result in adjustments that impact current period gross profit and income. Such changes are generally a result of differences between forecasted and actual return rate experience and costs to repair. If actual product return trends, costs to repair returned products or costs of customer compensatory claims differ significantly from estimates, future results of operations could be materially affected.

Litigation and Other Contingencies

When the Company becomes aware of a claim or potential claim, the Company assesses the likelihood of any loss or exposure. The Company discloses information regarding each material claim where the likelihood of a loss contingency is probable or reasonably possible. If a loss contingency is probable and the amount of the loss can be reasonably estimated, the Company records an accrual for the loss. In such cases, there may be an exposure to potential loss in excess of the amount accrued. Where a loss is not probable but is reasonably possible or where a loss in excess of the amount accrued is reasonably possible, the Company discloses an estimate of the amount of the loss or range of possible losses for the claim if a reasonable estimate can be made, unless the amount of such reasonably possible losses is not material to the Company’s financial position, results of operations or cash flows. The ability to predict the ultimate outcome of such matters involves judgments, estimates and inherent uncertainties. The actual outcome of such matters could differ materially from management’s estimates. See Note 5.

Advertising Expense

Advertising costs are expensed as incurred. Selling, general and administrative expenses of the Company included advertising costs of $61 million, $30 million and $11 million in 2013, 2012 and 2011, respectively.

Income Taxes

The Company accounts for income taxes under the asset and liability method, which provides that deferred tax assets and liabilities be recognized for temporary differences between the financial reporting basis and the tax basis of assets and liabilities and expected benefits of utilizing net operating loss (“NOL”) and tax credit carryforwards. The Company records a valuation allowance when it is more likely than not that the deferred tax assets will not be realized. Each period, the Company evaluates the need for a valuation allowance for its deferred tax assets and adjusts the valuation allowance so that the Company records net deferred tax assets only to the extent that it has concluded it is more likely than not that these deferred tax assets will be realized.

The Company recognizes liabilities for uncertain tax positions based on a two-step process. To the extent a tax position does not meet a more-likely-than-not level of certainty, no benefit is recognized in the financial statements. If a position meets the more-likely-than-not level of certainty, it is recognized in the financial statements at the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. Interest and penalties related to unrecognized tax benefits are recognized on liabilities recorded for uncertain tax positions and are recorded in the provision for income taxes. The actual liability for unrealized tax benefits in any such contingency may be materially different from the Company’s estimates, which could result in the need to record additional liabilities for unrecognized tax benefits or potentially adjust previously-recorded liabilities for unrealized tax benefits, and may materially affect the Company’s operating results.

Income per Common Share

The Company computes basic income per common share using net income and the weighted average number of common shares outstanding during the period. Diluted income per common share is computed using net income and the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Potentially dilutive common shares include certain dilutive outstanding employee stock options, rights to purchase shares of common stock under the Company’s Employee Stock Purchase Plan (“ESPP”) and restricted stock unit awards (“RSUs”).

The following table illustrates the computation of basic and diluted income per common share (in millions, except per share data):