SC TO-T/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Schedule TO/A

Amendment No. 9

Tender Offer Statement under Section 14(d)(1) or 13(e)(1)

of the Securities Exchange Act of 1934

Data Domain, Inc.

(Name of Subject Company (Issuer))

Envoy Merger Corporation

and

EMC Corporation

(Names of Filing Persons (Offerors))

COMMON STOCK, PAR VALUE $0.0001 PER SHARE

(Title of Class of Securities)

23767P109

(CUSIP Number of Class of Securities)

Paul T. Dacier, Esq.

EMC Corporation

176 South Street

Hopkinton, Massachusetts 01748

(508) 435-1000

(Name, Address and Telephone Number of Person Authorized to Receive Notices

and Communications on Behalf of Filing Persons)

CALCULATION OF FILING FEE

Transaction Valuation*	Amount of Filing Fee**
$ 2,245,672,600.50	$125,308.53

* For purposes of calculating the filing fee pursuant to Rule 0-11(d) only, the Transaction Valuation was calculated on the basis of (i) the aggregate of 67,035,003 shares of common stock, par value $0.0001 per share, of Data Domain, Inc., consisting of: (a) 61,539,064 shares of common stock issued and outstanding and (b) 5,495,939 shares of common stock issuable on or before expiration of the offer upon the exercise of vested stock options, and (ii) the tender offer price of $33.50 per Share.

** The filing fee, calculated in accordance with Rule 0-11 of the Securities Exchange Act of 1934, is calculated by multiplying the Transaction Valuation by .00005580.

þ Check the box if any part of the fee is offset as provided by Rule 0-11 (a) (2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid:	$112,216.60	Filing Party:	Envoy Merger Corporation and EMC Corporation
Form or Registration No.:	Schedule TO-T	Date Filed:	June 2, 2009
Amount Previously Paid:	$13,091.93	Filing Party:	Envoy Merger Corporation and EMC Corporation
Form or Registration No.:	Schedule TO-T/A	Date Filed:	July 6, 2009

¨ Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

þ third-party tender offer subject to Rule 14d-1.

¨ issuer tender offer subject to Rule 13e-4.

¨ going-private transaction subject to Rule 13e-3.

¨ amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer:   ¨

CUSIP Number:

23767P109

This Amendment No. 9 (“Amendment No. 9”) amends and supplements the Tender Offer Statement on Schedule TO originally filed on June 2, 2009, as amended on June 3, 2009, June 9, 2009, June 15, 2009, June 17, 2009, June 26, 2009, July 6, 2009, July 9, 2009 and July 10, 2009 (the “Schedule TO”) by EMC Corporation, a Massachusetts corporation (“EMC”), and Envoy Merger Corporation, a Delaware corporation (“Purchaser”) and a wholly owned subsidiary of EMC, relating to the offer by Purchaser to purchase all outstanding shares of common stock, par value $0.0001 per share, of Data Domain, Inc., a Delaware corporation (“Data Domain”), at a price of $33.50 per Share, net to the seller in cash, without interest thereon and subject to reduction for any applicable withholding taxes, upon the terms and subject to the conditions set forth in the Offer to Purchase dated June 2, 2009 and annexed to and filed as Exhibit (a)(1)(i) to the Schedule TO, as amended (the “Offer to Purchase”), and in the related Letter of Transmittal.

The information set forth in the Offer to Purchase is incorporated by reference to all the items of this Amendment No. 9. All capitalized terms used in this Amendment No. 9 without definition have the meanings ascribed to them in the Offer to Purchase.

The items of the Schedule TO set forth below are hereby amended and supplemented as follows:

Item 1 through 9, and Item 11.

The initial offering period expired at 12:00 midnight, New York City time, on Friday, July 17, 2009. Upon expiration of the Offer, Purchaser accepted for payment in accordance with the terms of the Offer all Shares that were validly tendered and not withdrawn prior to expiration of the Offer (including all Shares delivered through notices of guaranteed delivery), and payment for such Shares will be made promptly, in accordance with the terms of the Offer. The Depositary for the Offer has advised EMC and Purchaser that, as of the expiration of the Offer, a total of approximately 50,947,657 Shares were validly tendered to Purchaser and not withdrawn (not including Shares delivered through notices of guaranteed delivery), representing approximately 78.2% of the Shares outstanding. In addition to the Shares tendered in the Offer, EMC beneficially owns 2,534,697 Shares, representing approximately 3.9% of the Shares outstanding, which were acquired through ordinary brokerage transactions at prevailing market prices prior to the commencement of the Offer. Such previously-owned Shares, together with the Shares validly tendered to Purchaser and not withdrawn (not including Shares delivered through notices of guaranteed delivery), represent approximately 82.1% of the Shares outstanding.

On July 20, 2009, EMC issued a press release announcing that Purchaser had commenced a subsequent offering period for all remaining untendered Shares. The subsequent offering period will expire at 12:00 midnight, New York City time, on Wednesday, July 22, 2009, unless extended. Any such extension will be followed by a public announcement no later than 9:00 a.m., New York City time, on July 23, 2009.

The same $33.50 per Share price offered in the initial offering period will be paid during the subsequent offering period. Purchaser will immediately accept for payment all Shares validly tendered during this subsequent offering period, and payment will be made promptly after acceptance, in accordance with the terms of the Offer. Procedures for tendering Shares during the subsequent offering period are the same as during the initial offering period with two exceptions: (1) Shares cannot be delivered by the guaranteed delivery procedure, and (2) pursuant to Rule 14d-7(a)(2) promulgated under the Securities Exchange Act of 1934, as amended, Shares tendered during the subsequent offering period may not be withdrawn. The full text of the press release issued by EMC is set forth as Exhibit (a)(1)(xx) hereto and is incorporated by reference herein.

Item 12. Exhibits.

Item 12 of the Schedule TO is hereby amended and supplemented to add the following exhibits:

“(a)(1)(xx) Text of press release issued by EMC dated July 20, 2009”

SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: July 20, 2009

EMC CORPORATION
By:	/s/ Paul T. Dacier
Name: Title:	Paul T. Dacier Executive Vice President and General Counsel

ENVOY MERGER CORPORATION
By:	/s/ Paul T. Dacier
Name: Title:	Paul T. Dacier President

EXHIBIT INDEX

(a)(1)(i)	Offer to Purchase dated June 2, 2009 *
(a)(1)(ii)	Form of Letter of Transmittal (including Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9) *
(a)(1)(iii)	Form of Notice of Guaranteed Delivery *
(a)(1)(iv)	Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees *
(a)(1)(v)	Form of Letter to Clients for use by Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees *
(a)(1)(vi)	Form of summary advertisement dated June 2, 2009 *
(a)(1)(vii)	Text of press release issued by EMC dated June 1, 2009 (incorporated by reference to Exhibit 99.1 of the Current Report on Form 8-K filed by EMC with the Securities and Exchange Commission on June 1, 2009) *
(a)(1)(viii)	Slide Presentation dated June 1, 2009 (incorporated by reference to Exhibit 99.1 of the Schedule TO filed by EMC and Purchaser with the Securities and Exchange Commission on June 2, 2009) *
(a)(1)(ix)	Transcript of conference call held on June 1, 2009 *
(a)(1)(x)	Text of press release issued by EMC dated June 3, 2009 *
(a)(1)(xi)	Open letter to Data Domain employees, as published on June 9, 2009 *
(a)(1)(xii)	Text of press release issued by EMC dated June 15, 2009 *
(a)(1)(xiv)	Text of press release issued by EMC dated June 17, 2009 *
(a)(1)(xv)	Text of press release issued by EMC dated June 26, 2009 *
(a)(1)(xvi)	Text of press release issued by EMC dated July 6, 2009 *
(a)(1)(xvii)	Preliminary Proxy Statement on Schedule 14A of EMC and Purchaser (incorporated by reference to the Preliminary Proxy Statement on Schedule 14A filed by EMC and Purchaser with the Securities and Exchange Commission on July 6, 2009) *
(a)(1)(xviii)	Text of press release issued by EMC dated July 8, 2009 *
(a)(1)(xix)	Letter to Data Domain employees from Messrs. Tucci and Slootman dated July 9, 2009 *
(a)(1)(xx)	Text of press release issued by EMC dated July 20, 2009
(b)	Not applicable
(c)	Not applicable
(d)(1)(i)	Form of Agreement and Plan of Merger by and among EMC, Purchaser and Data Domain (incorporated by reference to Exhibit 99.2 of the Current Report on Form 8-K filed by EMC with the Securities and Exchange Commission on June 1, 2009) *
(d)(1)(ii)	Proposed Agreement and Plan of Merger by and among EMC, Purchaser and Data Domain delivered to Data Domain on July 6, 2009 *
(d)(1)(iii)	Agreement and Plan of Merger by and among EMC, Purchaser and Data Domain delivered to Data Domain, dated July 8, 2009 (incorporated by reference to Exhibit 2.1 of the Current Report on Form 8-K filed by Data Domain with the Securities and Exchange Commission on July 8, 2009) *
(g)	Not applicable
(h)	Not applicable

* Previously filed

EX-99. (A) (1) (XX)

Exhibit (a)(1)(xx)

Contact:    Michael Gallant

508-293-6357

Gallant_Michael@emc.com

EMC ACQUIRES MAJORITY OWNERSHIP OF

DATA DOMAIN

Announces Subsequent Offering Period to Expire on July 22;

Data Domain To Become Foundation of New Product Division Focused On

Next-Generation Backup, Recovery and Archive

HOPKINTON, Mass. – July 20, 2009 — EMC Corporation (NYSE: EMC), the world leader in information infrastructure solutions, today announced that it has acquired majority ownership of Data Domain, Inc. (NASDAQ: DDUP). Once EMC completes the acquisition of Data Domain, which is expected by the end of July, Data Domain will become the foundation of a new product division within EMC’s storage business focused on the development and delivery of next-generation disk-based backup, recovery and archive solutions.

The new EMC product division will be led by Frank Slootman, Data Domain’s President and CEO, reporting to Joe Tucci, EMC’s Chairman, President and CEO, and Frank Hauck, EMC Executive Vice President leading EMC’s Storage Business. EMC will increase its investment in the division, adding resources, technologies, and products. The company expects this new division to continue growing revenue at significant double-digit rates achieving $1 billion in revenue in 2010. EMC and Data Domain’s highly complementary technologies will continue to deliver customers tremendous savings and value while promising entirely new and exciting prospects for integrated solutions in the future.

Joe Tucci said, “I am delighted to welcome Data Domain and its dedicated, talented and seasoned team to the EMC family. Together we will shape the future of next-generation disk-based backup, recovery and archive solutions, making life significantly better for our joint customers, changing the game in the storage software market, and creating new market opportunities for growth.”

Frank Slootman added, “We are pleased to see the merger with EMC becoming a reality. We envision great opportunity to accelerate our business through EMC’s massive worldwide distribution network and customer base, and we can’t wait to begin seeing that play out in the market place.”

Data Domain stockholders have tendered approximately 78.2 percent of the outstanding Data Domain shares (not including shares tendered by notice of guaranteed delivery). Together with the 3.9 percent of outstanding Data Domain shares previously held by EMC, EMC now controls approximately 82.1 percent of Data Domain shares outstanding.

The initial offering period of EMC’s tender offer to purchase all of the outstanding shares of Data Domain common stock expired at 12:00 midnight, Eastern Daylight Time (EDT), on Friday, July 17, 2009. EMC has accepted for payment the approximately 50,947,657 shares tendered in the offer.

EMC also today announced a subsequent offering period commencing on Monday, July 20, 2009 and expiring at 12:00 midnight EDT, on Wednesday, July 22, 2009, unless further extended. The subsequent offering period will permit all stockholders who did not tender shares in the initial offering period to obtain the $33.50 per share offer price for their shares prior to consummation of the second-step merger. EMC expects to complete the second-step merger and close the acquisition shortly after expiration of the subsequent offering period so long as EMC controls 90% or more of the outstanding Data Domain shares at such time.

During the subsequent offering period, EMC’s acquisition subsidiary Envoy Merger Corporation will accept for payment and promptly pay for Data Domain shares as they are tendered. Stockholders who tender shares during such period will be paid the same $33.50 per share cash consideration paid during the initial offering period. During the subsequent offering period, shares may not be tendered through procedures for guaranteed delivery and shares tendered may not be withdrawn. Envoy Merger Corporation may extend the subsequent offering period. If the subsequent offering period is extended, Envoy Merger Corporation will notify the depositary for the offer and issue a press release prior to 9:00 a.m. EDT on Thursday, July 23, 2009.

About EMC

EMC Corporation (NYSE: EMC) is the world’s leading developer and provider of information infrastructure technology and solutions that enable organizations of all sizes to transform the way they compete and create value from their information. Information about EMC’s products and services can be found at www.EMC.com.

EMC is a registered trademark of EMC Corporation. All other trademarks used are the property of their respective owners.

Information about the Tender Offer

This press release is neither an offer to purchase nor a solicitation of an offer to sell any shares of Data Domain. EMC and Envoy Merger Corporation (“Envoy”) have filed with the Securities and Exchange Commission (“SEC”) a tender offer statement on Schedule TO containing an offer to purchase, forms of letters of transmittal and other documents relating to the tender offer, and these documents have been mailed to the stockholders of Data Domain. These documents contain important information about the tender offer and stockholders of Data Domain are urged to read them. Investors and stockholders of Data Domain are able to obtain a free copy of these documents and other documents filed by EMC and Envoy with the SEC at the website maintained by the SEC at www.sec.gov. In addition, the tender offer statement and related materials may also be obtained free of charge by directing a request to the Information Agent for the offer, Morrow & Co., LLC at (800) 662-5200, or by email at emc.info@morrowco.com.

Forward-Looking Statements

This release contains “forward-looking statements” as defined under the Federal Securities Laws. Actual results could differ materially from those projected in the forward-looking statements as a result of certain risk factors, including but not limited to: (i) adverse changes in general economic or market conditions; (ii) delays or reductions in information technology spending; (iii) our ability to protect our proprietary technology; (iv) risks associated with managing the growth of our business, including risks associated with acquisitions and investments and the challenges and costs of integration, restructuring and achieving anticipated synergies; (v) fluctuations in VMware, Inc.’s operating results and risks associated with trading of VMware stock; (vi) competitive factors, including but not limited to pricing pressures and new product introductions; (vii) the relative and varying rates of product price and component cost declines and the volume and mixture of product and services revenues; (viii) component and product quality and availability; (ix) the transition to new products, the uncertainty of customer acceptance of new product offerings and rapid technological and market change; (x) insufficient, excess or obsolete inventory; (xi) war or acts of terrorism; (xii) the ability to attract and retain highly qualified employees; (xiii) fluctuating currency exchange rates; (xiv) litigation that we may be involved in; and (xv) other one-time events and other important factors disclosed previously and from time to time in EMC’s filings with the U.S. Securities and Exchange Commission. These statements are forward-looking, and actual results may differ materially. EMC disclaims any obligation to update any forward-looking statements in this release after the date of this release.