Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  EMC CORP
2. Date of Event Requiring Statement (Month/Day/Year)
07/20/2009
3. Issuer Name and Ticker or Trading Symbol
Data Domain, Inc. [DDUP]
(Last)
(First)
(Middle)
176 SOUTH STREET
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

HOPKINTON, MA 01748
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock, par value $0.0001 per share 53,482,354 (1) (2)
I
See Footnote (3)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
EMC CORP
176 SOUTH STREET
HOPKINTON, MA 01748
    X    

Signatures

/s/ Paul T. Dacier, Executive Vice President and General Counsel 07/20/2009
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) On July 8, 2009, EMC Corporation, a Massachusetts corporation ("EMC"), Envoy Merger Corporation, a Delaware corporation and a wholly owned subsidiary of EMC ("Purchaser"), and Data Domain, Inc., a Delaware corporation (the "Company"), entered into an Agreement and Plan of Merger (the "Merger Agreement"). As contemplated by the terms of the Merger Agreement, Purchaser commenced, on June 2, 2009, a cash tender offer (the "Offer") to purchase all outstanding shares (the "Shares") of common stock, par value $0.0001 per Share, of the Company, at a price of $33.50 per Share, net to the seller in cash, and subject to the terms and conditions set forth in the Offer to Purchase, dated June 2, 2009, as amended, included as an exhibit to the Tender Offer Statement on Schedule TO filed by EMC and Purchaser with the Securities and Exchange Commission (the "SEC") on June 2, 2009.
(2) The Offer expired at 12:00 midnight, New York City time, on Friday, July 17, 2009. An aggregate of 50,947,657 Shares were validly tendered and not withdrawn (not including certain shares tendered under guaranteed delivery procedures), representing approximately 78.2% of the Company's outstanding common stock. On July 20, 2009, Purchaser accepted for payment all validly tendered and not withdrawn Shares. Prior to the commencement of the Offer, on May 29, 2009 and June 1, 2009, Woodland Street Partners, Inc., a Delaware corporation and a wholly owned subsidiary of EMC ("Woodland"), acquired 2,534,697 Shares through ordinary brokerage transactions at prevailing market prices.
(3) Purchaser is a direct, wholly owned subsidiary of EMC and is the owner of the Shares purchased in the Offer. Woodland is a direct, wholly owned subsidiary of EMC and is the owner of 2,534,697 Shares acquired through ordinary brokerage transactions at prevailing market prices prior to the commencement of the Offer.

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