As filed with the Securities and Exchange Commission on March 28, 2013

Registration No. 333-      

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM S-8

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

METABOLIX, INC.

(Exact Name of Registrant as Specified in Its Charter)

Delaware

(State or Other Jurisdiction of Incorporation or Organization)

04-3158289

(I.R.S. Employer Identification No.)

Metabolix, Inc.

21 Erie Street

Cambridge, MA 02139

(Address of Principal Executive Offices) (Zip Code)

2006 Stock Option and Incentive Plan

(Full Title of the Plan)

Richard P. Eno

Chief Executive Officer

Metabolix, Inc.

21 Erie Street

Cambridge, MA 02139

(Name and Address of Agent for Service)

(617) 583-1700

(Telephone Number, Including Area Code, of Agent For Service)

Copies to:

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.

CALCULATION OF REGISTRATION FEE

This Registration Statement registers additional securities of the same class as other securities for which a registration statement filed on Form S-8 (SEC File No. 333-138631) relating to an employee benefit plan of the Registrant is effective. The information contained in the Registrant’s registration statement on Form S-8 (SEC File No. 333-138631) is hereby incorporated by reference pursuant to General Instruction E to Form S-8.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

The following documents filed with the Commission are incorporated by reference in this Registration Statement:

(a)         The Registrant’s Annual Report on Form 10-K for the year ended December 31, 2012, filed on March 28, 2013;

(b)         All other reports filed pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) since December 31, 2012; and

(c)          The section entitled “Description of Registrant’s Securities to be Registered” contained in the Registrant’s Registration Statement on Form 8-A, filed pursuant to Section 12(b) of the Exchange Act, on November 6, 2006, including any amendment or report filed for the purpose of updating such description.

All documents subsequently filed with the Commission by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, on or after the date of this Registration Statement and prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered herein have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and to be a part thereof from the date of filing of such documents.

Item 8. Exhibits.

See the Exhibit Index on the page immediately preceding the exhibits for a list of exhibits filed as part of this Registration Statement on Form S-8, which Exhibit Index is incorporated herein by reference.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cambridge, Commonwealth of Massachusetts, on March 28, 2013.

POWER OF ATTORNEY AND SIGNATURES

We, the undersigned officers and directors of Metabolix, Inc. (the “Company”), hereby severally constitute and appoint Richard P. Eno, Joseph D. Hill, and Sarah P. Cecil, and each of them singly, our true and lawful attorneys, with full power to them, and to each of them singly, to sign for us and in our names in the capacities indicated below, any and all amendments to this Registration Statement, and all other documents in connection therewith to be filed with the Securities and Exchange Commission, and generally to do all things in our names and on our behalf in such capacities to enable the Company to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated:

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INDEX TO EXHIBITS

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Exhibit 5.1

March 28, 2013

Metabolix, Inc.

21 Erie Street

Cambridge, MA 02139

Re:          Securities Being Registered under Registration Statement on Form S-8

Ladies and Gentlemen:

We have acted as counsel to you in connection with your filing of a Registration Statement on Form S-8 (the “Registration Statement”) pursuant to the Securities Act of 1933, as amended (the “Securities Act”), on or about the date hereof relating to an aggregate of 387,462 shares (the “Shares”) of Common Stock, $0.01 par value per share, of Metabolix, Inc., a Delaware corporation (the “Company”), that may be issued pursuant to the Company’s 2006 Stock Option and Incentive Plan (the “Plan”).

We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinion expressed below.  We have relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinion set forth below, on certificates of officers of the Company.

The opinion expressed below is limited to the Delaware General Corporation Law (which includes reported judicial decisions interpreting the Delaware General Corporation Law).

For purposes of the opinion expressed below, we have assumed that a sufficient number of authorized but unissued shares of the Company’s Common Stock will be available for issuance when the Shares are issued.

Based on the foregoing, we are of the opinion that the Shares have been duly authorized and, upon issuance and delivery against payment therefor in accordance with the terms of the Plan, will be validly issued, fully paid and nonassessable.

We hereby consent to the inclusion of this opinion as Exhibit 5.1 to the Registration Statement.  In giving our consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

Exhibit 23.2

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-8 of our report dated March 28, 2013 relating to the financial statements and the effectiveness of internal control over financial reporting, which appears in Metabolix, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2012.

/s/ PricewaterhouseCoopers LLP
Boston, Massachusetts

March 28, 2013