Exhibit 5.1

		VICTOR I. LEWKOW		CARMINE D. BOCCUZZI, JR		JARED GERBER
		LESLIE N. SILVERMAN		JEFFREY D. KARPF		COLIN D. LLOYD
		LEE C. BUCHHEIT		KIMBERLY BROWN BLACKLOW		COREY M. GOODMAN
		THOMAS J. MOLONEY		ROBERT J. RAYMOND		RISHI ZUTSHI
		DAVID G. SABEL		SUNG K. KANG		JANE VANLARE
One Liberty Plaza New York, NY 10006-1470 T: +1212 225 2000 F: +1212 225 3999   clearygottlieb.com		JONATHAN I. BLACKMAN		LEONARD C. JACOBY		DAVID H. HERRINGTON
		MICHAEL L. RYAN		SANDRA L. FLOW		KIMBERLY R. SPOERRI
		ROBERT P. DAVIS		FRANCISCO L. CESTERO		AARON J. MEYERS
		YARON Z. REICH		FRANCESCA L. ODELL		DANIEL C. REYNOLDS
		RICHARD S. LINCER		WILLIAM L. MCRAE		ABENA A. MAINOO
		STEVEN G. HOROWITZ		JASON FACTOR		HUGH C. CONROY, JR.
		JAMES A. DUNCAN		MARGARET S. PEPONIS		RESIDENT PARTNERS
		STEVEN M. LOEB		LISA M. SCHWEITZER
		CRAIG B. BROD		JUAN G. GIRALDEZ		SANDRA M. ROCKS
		EDWARD J. ROSEN		DUANE MCLAUGHLIN		S. DOUGLAS BORISKY
		NICOLAS GRABAR		BREON S. PEACE		JUDITH KASSEL
		CHRISTOPHER E. AUSTIN		MEREDITH E. KOTLER		DAVID E. WEBB
		SETH GROSSHANDLER		CHANTAL E. KORDULA		PENELOPE L. CHRISTOPHOROU
		HOWARD S. ZELBO		BENETJ.O’REILLY		BOAZ S. MORAG
		DAVID E. BRODSKY		ADAM E. FLEISHER		MARY E. ALCOCK
		ARTHUR H. KOHN		SEAN A. O’NEAL		HEIDE H. ILGENFRITZ
		RICHARD J. COOPER		GLENN P. MCGRORY		KATHLEEN M. EMBERGER
		JEFFREY S. LEWIS		MATTHEW P. SALERNO		WALLACE L. LARSON. JR.
		PAUL J. SHIM		MICHAEL J. ALBANO		AVRAM E. LUFT
		STEVEN L. WILNER		VICTOR L. HOU		ANDREW WEAVER
		ERIKA W. NIJENHUIS		ROGER A. COOPER		HELENA K. GRANNIS
		ANDRES DE LA CRUZ		AMY R. SHAPIRO		JOHN V. HARRISON
		DAVID C. LOPEZ		JENNIFER KENNEDY PARK		CAROLINE F. HAYDAY
		JAMES L. BROMLEY		ELIZABETH LENAS		RAHUL MUKHI
		MICHAEL A. GERSTENZANG		LUKE A. BAREFOOT		NEIL R. MARKEL
WASHINGTON, D.C. • PARIS • BRUSSELS • LONDON • MOSCOW		LEWIS J. LIMAN		PAMELA L. MARCOGLIESE		HUMAYUN KHALID
FRANKFURT • COLOGNE • ROME • MILAN • HONG KONG		LEV L. DASSIN		PAUL M. TIGER		KENNETH S. BLAZEJEWSKI
BEIJING • BUENOS AIRES • SÁO PAULO • ABU DHABI • SEOUL		NEIL Q. WHORISKEY		JONATHAN S. KOLODNER		ANDREA M. BASHAM
		JORGE U. JUANTORENA		DANIEL lLAN		LAURA BAGARELLA
		MICHAEL D. WEINBERGER		MEYER H. FEDIDA		SHIRLEY M. LO
D: +1 212 225-2680 skang@cgsh.com		DAVID LEINWAND		ADRIAN R. LEIPSIC		RESIDENT COUNSEL
		DIANA L. WOLLMAN		ELIZABETH VICENS
		JEFFREY A. ROSENTHAL		ADAM J. BRENNEMAN		LOUISE M. PARENT
		ETHAN A. KLINGSBERG		ARI D. MACKINNON		OF COUNSEL
		MICHAEL D. DAYAN		JAMES E. LANGSTON

February 13, 2018                        

Western Digital Corporation

5601 Great Oaks Parkway

San Jose, California 95119

Ladies and Gentlemen:

We have acted as special counsel to Western Digital Corporation, a Delaware corporation (the “Company”), and the Guarantors (as defined below) in connection with the Company’s offering pursuant to a registration statement on Form S-3 (No. 333-222762) (as amended and including the documents incorporated by reference therein, the “Registration Statement”) and the prospectus, dated January 30, 2018 (including the documents incorporated by reference therein, the “Prospectus”), of $2,300,000,000 aggregate principal amount of its 4.750% Senior Notes due 2026 (the “Notes”). The Notes will be fully and unconditionally guaranteed by HGST, Inc., a Delaware corporation, WD Media, LLC, a Delaware limited liability company, Western Digital (Fremont), LLC, a Delaware limited liability company, and Western Digital Technologies, Inc., a Delaware corporation (the “Guarantors” and, together with the Company, the “Registrants”). The Notes will be issued under an indenture, dated as of February 13, 2018 (the “Indenture”), between the Company, the Guarantors and U.S. Bank National Association, as trustee (the “Trustee”). The Indenture includes the guarantees of the Notes by the Guarantors (the “Guarantees”).

In arriving at the opinions expressed below, we have reviewed the following documents:

(a) the Registration Statement;

(b) the Prospectus;

Cleary Gottlieb Steen & Hamilton LLP or an affiliated entity has an office in each of the cities listed above.

Western Digital Corporation, p. 2

(c) an executed copy of the Underwriting Agreement, dated January 30, 2018, between the Company, the Guarantors and the Representatives, on behalf of themselves and the several underwriters named in Schedule I thereto;

(d) facsimile copies of the Notes in global form as executed by the Company and authenticated by the Trustee;

(e) an executed copy of the Indenture; and

(f) copies of the certificates of organization or similar formation documents and the bylaws or operating agreements of each of the Company and Guarantors, as applicable, certified by the Secretary of State of the State of Delaware and the corporate secretary of the Company or Guarantor, as applicable.

In addition, we have reviewed the originals or copies certified or otherwise identified to our satisfaction of all such corporate records of the Company and the Guarantors and such other documents, and we have made such investigations of law, as we have deemed appropriate as a basis for the opinions expressed below.

In rendering the opinions expressed below, we have assumed the authenticity of all documents submitted to us as originals and the conformity to the originals of all documents submitted to us as copies. In addition, we have assumed and have not verified the accuracy as to factual matters of each document we have reviewed.

Based on the foregoing, and subject to the further assumptions and qualifications set forth below, it is our opinion that (a) the Notes are the valid, binding and enforceable obligations of the Company, entitled to the benefits of the Indenture, and (b) the Guarantees are the valid, binding and enforceable obligations of the Guarantors, entitled to the benefits of the Indenture.

Insofar as the foregoing opinions relate to the validity, binding effect or enforceability of any agreement or obligation of any Registrant, (a) we have assumed that such Registrant and each other party to such agreement or obligation has satisfied those legal requirements that are applicable to it to the extent necessary to make such agreement or obligation enforceable against it (except that no such assumption is made as to any of the Registrants regarding matters of the law of the State of New York, the General Corporation Law of the State of Delaware or the Limited Liability Company Act of the State of Delaware that in our experience normally would be applicable to general business entities with respect to such agreement or obligation), (b) we express no opinion with respect to the effect of any mandatory choice of law rules and (c) such opinions are subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and to general principles of equity.

We note that (i) the waiver of defenses contained in Sections 11.06 and 11.13 of the Indenture may be ineffective to the extent that any such defense involves a matter of public policy in the State of New York and (ii) the enforceability of indemnification provisions may be subject to public policy considerations.

Western Digital Corporation, p. 3

The foregoing opinions are limited to the law of the State of New York, the General Corporation Law of the State of Delaware and the Limited Liability Company Act of the State of Delaware.

We hereby consent to the filing of this opinion letter as Exhibit 5.1 to the Company’s Current Report on Form 8-K dated February 13, 2018. In giving this consent, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended, or the rules and regulations of the Securities and Exchange Commission thereunder. The opinions expressed herein are rendered on and as of the date hereof, and we assume no obligation to advise you or any other person, or to make any investigations, as to any legal developments or factual matters arising subsequent to the date hereof that might affect the opinions expressed herein.