UNITED STATES


SECURITIES AND EXCHANGE COMMISSION


WASHINGTON, D.C. 20549


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FORM 10-K/A


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AMENDMENT NO. 1 TO FORM 10-K


(Mark One)


xANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934


For the fiscal year ended December 31, 2011


OR


 ̈TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934


For the transition period from  to


Commission file number 001-13828


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MEMC Electronic Materials, Inc.


(Exact name of registrant as specified in its charter)


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Delaware56-1505767(State or other jurisdiction ofincorporation or organization)(I.R.S. EmployerIdentification No.)





501 Pearl Drive (City of O’Fallon)St. Peters, Missouri63376(Address of principal executive offices)(Zip Code)


Registrant’s telephone number, including area code:


(636) 474-5000


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Securities registered pursuant to Section 12(b) of the Act:


Title of Each ClassName of Each Exchange on Which Registered:$.01 Par Value Common StockNew York Stock Exchange


Securities Registered Pursuant to Section 12(g) of the Act:


None


(Title of Class)


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Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes x No o


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Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes o No x


Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes x No  ̈


Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes x No  ̈


Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ̈


Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):


Large accelerated filer x Accelerated filer  ̈ Non-accelerated filer  ̈ Smaller reporting company  ̈


Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ̈ No x





The aggregate market value of the registrant's Common Stock held by nonaffiliates of the registrant, based upon the closing price of such stock on June 30, 2011 of $8.53 as reported by the New York Stock Exchange, and 229,865,540 shares outstanding on such date, was approximately $1,960,753,056. The number of shares outstanding of the registrant's Common Stock as of February 24, 2012, was 241,279,694 shares.


DOCUMENTS INCORPORATED BY REFERENCE


1. Portions of the registrant’s 2011 Annual Report to Stockholders (Part I and Part II)


2. Portions of the registrant’s 2012 Proxy Statement (Part III)


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PART IV


Item 15.Exhibits, Financial Statement Schedules


3. Exhibits





The registrant is filing this Form 10-K/A to provide the conformed signature of KPMG LLP which was inadvertently omitted from the Report of Independent Registered Public Accounting Firm which appears at pages 106 and 107 of Exhibit 13 (selected pages from the registrant's 2011 Annual Report to Stockholders) and the Consent of Independent Registered Public Accounting Firm appearing at Exhibit 23.  There are no changes to any other pages of Exhibit 13 or Exhibit 23.





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SIGNATURES


Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.





MEMC ELECTRONICMATERIALS, INC.By:/s/ Mark J. MurphyMark J. MurphySenior Vice President and Chief Financial OfficerDate:March 1, 2012











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EXHIBIT INDEX


The following are filed as part of this Amendment No. 1 to Form 10-K:





Exhibit No.Description13Selected pages from the Company's 2011 Annual Report to Stockholders (Filing only the conformed executed Report of Independent Registered Public Accounting Firm)23Consent of KPMG LLP





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