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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
The Board of Directors and Shareholders
Western Digital Corporation:
We have audited Western Digital Corporation's internal control over financial reporting as of June 29, 2012,
based on criteria established in Internal Control -- Integrated Framework issued by the Committee of Sponsoring Orga-
nizations of the Treadway Commission (COSO). The Company's management is responsible for maintaining effective
internal control over financial reporting and for its assessment of the effectiveness of internal control over financial
reporting, included in the accompanying Management's Report on Internal Control Over Financial Reporting appear-
ing under Item 9A. Our responsibility is to express an opinion on the Company's internal control over financial
reporting based on our audit.
We conducted our audit in accordance with the standards of the Public Company Accounting Oversight Board
(United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about
whether effective internal control over financial reporting was maintained in all material respects. Our audit included
obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness
exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk.
Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe
that our audit provides a reasonable basis for our opinion.
A company's internal control over financial reporting is a process designed to provide reasonable assurance regard-
ing the reliability of financial reporting and the preparation of financial statements for external purposes in accordance
with generally accepted accounting principles. A company's internal control over financial reporting includes those
policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly
reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions
are recorded as necessary to permit preparation of financial statements in accordance with U.S. generally accepted
accounting principles, and that receipts and expenditures of the company are being made only in accordance with
authorizations of management and directors of the company; and (3) provide reasonable assurance regarding pre-
vention or timely detection of unauthorized acquisition, use, or disposition of the company's assets that could have a
material effect on the financial statements.
Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstate-
ments. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may
become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures
may deteriorate.
In our opinion, Western Digital Corporation maintained, in all material respects, effective internal control over
financial reporting as of June 29, 2012, based on criteria established in Internal Control -- Integrated Framework issued
by the Committee of Sponsoring Organizations of the Treadway Commission.
We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board
(United States), the consolidated balance sheets of Western Digital Corporation and subsidiaries as of June 29, 2012
and July 1, 2011, the related consolidated statements of income, shareholders' equity and comprehensive income, and
cash flows for each of the years in the three-year period ended June 29, 2012, and the related financial statement
schedule, and our report dated August 17, 2012, expressed an unqualified opinion on those consolidated financial
statements and financial statement schedule.
/s/
KPMG LLP
August 17, 2012
Irvine, California
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