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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.          )

 

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METABOLIX, INC.

19 Presidential Way
Woburn, Massachusetts 01801
(617) 583-1700

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS

TO BE HELD ON DECEMBER 21, 2016

To the Stockholders of Metabolix, Inc.:

        A Special Meeting of Stockholders of Metabolix, Inc., a Delaware corporation (the "Company"), will be held on Wednesday, December 21, 2016, at 9:30 a.m., Eastern time, at the offices of the Company at 19 Presidential Way, Woburn, MA 01801, for the following purposes:

1.

To approve amendments to the Company's 2014 Stock Option and Incentive Plan (the "2014 Plan") to increase the number of shares authorized for issuance thereunder by 5,833,334 and to increase certain limits on individual awards under the 2014 Plan; and



2.

To transact such other business as may properly come before the Special Meeting and any adjournments or postponements thereof.

        Only stockholders of record at the close of business on November 18, 2016, are entitled to notice of and to vote at the Special Meeting and at any adjournment or postponement thereof.

        All stockholders are cordially invited to attend the Special Meeting in person. However, to assure your representation at the Special Meeting, we urge you, whether or not you plan to attend the Special Meeting, to complete, sign, date and mail promptly the enclosed proxy which is being solicited on behalf of the Board of Directors so that your shares will be represented at the Special Meeting. A return envelope which requires no postage if mailed in the United States is enclosed for that purpose. You need to vote in accordance with the instructions listed on the proxy card. If shares are held in a bank or brokerage account, you may be eligible to vote electronically or by telephone. Please refer to the enclosed voting instruction form for instructions. If you attend the Special Meeting, you may vote in person even if you have previously returned your proxy card.

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WHETHER OR NOT YOU EXPECT TO ATTEND THE SPECIAL MEETING, PLEASE COMPLETE, SIGN, DATE AND MAIL PROMPTLY THE ENCLOSED PROXY WHICH IS BEING SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS SO THAT YOUR SHARES WILL BE REPRESENTED AT THE SPECIAL MEETING. A RETURN ENVELOPE WHICH REQUIRES NO POSTAGE IF MAILED IN THE UNITED STATES IS ENCLOSED FOR THAT PURPOSE. YOU NEED TO VOTE IN ACCORDANCE WITH THE INSTRUCTIONS LISTED ON THE PROXY CARD. IF SHARES ARE HELD IN A BANK OR BROKERAGE ACCOUNT, YOU MAY BE ELIGIBLE TO VOTE ELECTRONICALLY OR BY TELEPHONE. PLEASE REFER TO THE ENCLOSED VOTING INSTRUCTION FORM FOR INSTRUCTIONS.

IN ACCORDANCE WITH OUR SECURITY PROCEDURES, ALL PERSONS ATTENDING THE SPECIAL MEETING WILL BE REQUIRED TO PRESENT PICTURE IDENTIFICATION.

METABOLIX, INC.

19 Presidential Way
Woburn, MA 01801

PROXY STATEMENT
For the Special Meeting of Stockholders
To Be Held on December 21, 2016

November 21, 2016

        Proxies in the form enclosed with this Proxy Statement are solicited by the Board of Directors of Metabolix, Inc., a Delaware corporation ("Metabolix" or the "Company"), for use at the Special Meeting of Stockholders of the Company to be held on Wednesday, December 21, 2016, at 9:30 a.m., Eastern time, or at any adjournments or postponements thereof (the "Special Meeting") at the offices of the Company at 19 Presidential Way, Woburn, MA 01801. This Proxy Statement and the form of proxy will be first sent or given to stockholders on or about November 28, 2016.

The purpose of the Special Meeting is:

1.

To approve amendments to the Company's 2014 Stock Option and Incentive Plan (the "2014 Plan") to increase the number of shares authorized for issuance thereunder by 5,833,334 and to increase certain limits on individual awards under the 2014 Plan; and



2.

To transact such other business as may properly come before the Special Meeting and any adjournments or postponements thereof.

        Only stockholders of record at the close of business on November 18, 2016 (the "Record Date") will be entitled to receive notice of and to vote at the Special Meeting. As of the Record Date, 28,342,625 shares of Common Stock were issued, outstanding and entitled to vote.

VOTING

        The holders of Common Stock are entitled to one vote per share on any proposal presented at the Special Meeting. Stockholders may vote in person or by proxy. Stockholders may vote by proxy by completing, signing, dating and returning the accompanying proxy card in the postage-prepaid envelope enclosed for that purpose in accordance with the instructions listed on the proxy card. Execution of a proxy will not in any way affect a stockholder's right to attend the Special Meeting and vote in person.

        Any proxy given pursuant to this solicitation may be revoked by the person giving it any time before the taking of the vote at the Special Meeting. Proxies may be revoked by (1) filing with the Secretary of the Company, before the taking of the vote at the Special Meeting, a written notice of revocation bearing a later date than the proxy, (2) duly executing a later-dated proxy relating to the same shares and delivering it to the Secretary of the Company, in accordance with the instructions listed on the proxy card, before the taking of the vote at the Special Meeting, (3) if shares are held in a bank or brokerage account and if eligible, by transmitting a subsequent vote over the Internet or by

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telephone, or (4) attending the Special Meeting and voting in person (although attendance at the Special Meeting will not in and of itself constitute a revocation of a proxy). Any written notice of revocation or subsequent proxy should be sent to Metabolix, Inc., 19 Presidential Way, Woburn, MA 01801, Attention: Secretary, so as to be delivered before the taking of the vote at the Special Meeting.

        If your shares are held by a broker on your behalf (that is, in "street name"), you may be required to present an account statement or letter from your bank or brokerage firm showing that you are the beneficial owner of the shares as of the Record Date in order to be admitted to the Special Meeting. To be able to vote your shares held in street name at the Special Meeting, you will need to obtain a proxy from the holder of record.

        The persons named as attorneys-in-fact in the proxies, Lynne H. Brum and Charles B. Haaser, were selected by the Board of Directors and are officers of the Company. All properly executed proxies returned in time to be counted at the Special Meeting will be voted by such persons at the Special Meeting as stated below. When a choice has been specified on the proxy with respect to a matter, the shares represented by the proxy will be voted in accordance with the specifications. If a proxy is submitted without giving voting instructions, such shares will be voted:

•

FOR the approval of the amendments to the 2014 Stock Option and Incentive Plan, and



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as the persons named as proxies may determine in their discretion with respect to any other matters properly presented at the Special Meeting.

        The representation in person or by proxy of at least a majority of the outstanding shares of Common Stock entitled to vote at the Special Meeting is necessary to constitute a quorum for the transaction of business. Abstentions and broker "non-votes" are counted as present or represented for purposes of determining the presence or absence of a quorum for the Special Meeting. A "non-vote" occurs when a nominee holding shares for a beneficial owner votes on one proposal but does not vote on another proposal because, with respect to such other proposal, the nominee does not have discretionary voting power and has not received instructions from the beneficial owner.

        If your shares are held in street name, and you do not instruct the broker as to how to vote your shares on Proposal 1, the broker may not exercise discretion to vote for or against that proposal. This would be a "broker non-vote" and these shares will not be counted as having been voted on that proposal. Please vote your proxy so your vote can be counted.

        Required Vote.    The affirmative vote of a majority of the shares of Common Stock cast by the stockholders present in person or represented by proxy at the Special Meeting is required to approve Proposal 1. Shares voted to abstain are included in the number of shares present or represented and voting on that proposal.

        Other Matters.    The Board knows of no other matters to be presented at the Special Meeting. If any other matter should be presented at the Special Meeting upon which a vote properly may be taken, the affirmative vote of the majority of shares present, in person or represented by proxy, and voting on that matter is required for approval and all such shares represented by proxies received by the Board will be voted with respect thereto in accordance with the judgment of the persons named as attorneys in the proxies. Shares voted to abstain are included in the number of shares present or represented and voting on each matter.

Important Notice Regarding the Availability of Proxy Materials for the Special Meeting: The proxy statement is available for viewing, printing and downloading at http://ir.metabolix.com/index.cfm.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

        The following table sets forth certain information regarding beneficial ownership of the Company's Common Stock as of November 10, 2016: (i) by each person known to us to be the beneficial owner of more than 5% of our outstanding shares of Common Stock; (ii) by each of our directors; (iii) by our "principal executive officer" and the two other most highly paid executive officers who were serving as executive officers on December 31, 2015 (our "named executive officers"); and (iv) by all of our directors and executive officers as a group. Unless otherwise noted below, the address of each person listed on the table is c/o Metabolix, Inc., 19 Presidential Way, Woburn, Massachusetts 02139.

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PROPOSAL 1

AMENDMENTS TO THE METABOLIX, INC. 2014 STOCK OPTION AND INCENTIVE PLAN

Proposal

        Our Board of Directors believes that the future success of the Company depends, in large part, upon our ability to attract, retain and motivate key employees and that the granting of stock options and other equity awards serves as an important factor in retaining key employees. The Board of Directors believes the current number of shares remaining available for issuance under the Metabolix, Inc. 2014 Stock Option and Incentive Plan (the "2014 Plan") is insufficient for this purpose. On October 31, 2016, on the recommendation of our Compensation Committee, our Board of Directors approved, subject to stockholder approval, amendments to the 2014 Plan (the "Amendments") to increase the aggregate number of shares authorized for issuance under the 2014 Plan by 5,833,334 shares, from 4,166,666 to 10,000,000 shares plus, in each case, the number of shares of Common Stock underlying any awards under our 2005 Stock Option Plan and 2006 Stock Option Plan that are forfeited, canceled or terminated (other than by exercise).

        The Amendments also increase the maximum award of stock options or stock appreciation rights that may be granted to any one individual from 500,000 to 2,000,000 shares of Common Stock for any calendar year period and increase the maximum award of restricted stock, restricted stock units or performance shares that can qualify as "performance-based compensation" under Section 162(m) of the

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Code from 500,000 to 2,000,000 shares of Common Stock to any one individual in any performance cycle (in each case, subject to adjustment for stock splits and similar events).

        The Board of Directors believes that the proposed Amendments are in the best interests of our Company and our stockholders, given our current expectations regarding the challenges facing the Company during the next several years and the highly competitive environment in which we recruit and retain employees, and recommends a vote for this proposal. A copy of the 2014 Plan, as it is proposed to be amended by the Amendments and restated, is attached as Appendix A to this proxy statement and is incorporated herein by reference.

        The Board of Directors believes that stock options and other stock-based incentive awards can play an important role in the success of the Company by encouraging and enabling the employees, officers, non-employee directors and other key persons of the Company and its subsidiaries upon whose judgment, initiative and efforts the Company largely depends for the successful conduct of its business to acquire a significant ownership interest in the Company. The Board of Directors anticipates that providing such persons with a meaningful direct stake in the Company will assure a closer identification of the interests of such individuals with those of the Company and its stockholders, thereby incentivizing their efforts on the Company's behalf and strengthening their desire to remain with the Company.

        The Company is completing a strategic restructuring under which Yield10 Bioscience has become its core business, with a focus on developing proprietary technologies to enable step-change improvements in yield for major food and feed crops. In connection with the restructuring, the Company is shifting the balance in employee compensation to increase the use of equity and reduce use of cash for at least the next year. The Board of Directors has also decided to temporarily suspend cash compensation to non-employee directors. The Compensation Committee expects that the payment of cash compensation to non-employee directors will be revisited during the second quarter of 2017 and that equity-based compensation to non-employee directors will be adjusted in light of the suspension of cash compensation. The Amendments are intended to ensure that the Company has the capacity to grant stock options and other equity awards to eligible recipients at levels determined to be appropriate by our Board of Directors and/or our Compensation Committee in order to retain, motivate, and incentivize Company employees, including executive officers and non-employee directors.

        On October 26, 2016, in connection with the restructuring of the Company, the Compensation Committee approved the grant of stock options under the 2014 Plan for an aggregate of 4,560,000 shares of Common Stock to employees, including executive officers. These grants included stock options for a total of 1,750,000 shares that were granted subject to and contingent upon approval of the Amendments by our stockholders (the "Contingent Employee Option Awards"). The Compensation Committee also approved two stock options for a total of 750,000 shares granted under the 2014 Plan on November 4, 2016 to Joseph Shaulson, our former president and chief executive officer, in connection with the termination of his employment with the Company. One of Mr. Shaulson's new stock option grants, for 350,000 of the 750,000 shares, is also subject to and contingent upon approval of the Amendments by our Stockholders (together with the Contingent Employee Option Awards, the "Contingent Option Awards"). If the stockholders do not approve the Amendments, the Contingent Option Awards will be automatically cancelled and be of no further force or effect.

        The Compensation Committee determined that it was in the best interests of the Company to make significant awards to continuing executives and employees (i) for retention during a period of significant change and continuing cash conservation, (ii) in light of the shifting balance between equity and cash compensation, including the suspension of the Company's cash bonus program, and (iii) as part of a broader shift to a more entrepreneurial approach with an increased emphasis on research and development as a critical success factor for the Company's Yield 10 Bioscience business.

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        At November 10, 2016, excluding the Contingent Option Awards, there were stock options to acquire 3,767,318 shares of Common Stock outstanding under our equity compensation plans, including the 2014 Plan. Also outstanding at November 10, 2016, was a non-qualified stock option to acquire 191,667 shares of Common Stock that was granted to Mr. Shaulson, not under a Company stock plan, as an inducement in connection with his joining the Company. There are 312,532 unvested restricted stock units with time-based vesting outstanding under the 2014 Plan. The outstanding stock options at November 10, 2016 have a weighted-average exercise price of $5.5738 and a weighted-average remaining term of 1.94 years. At November 10, 2016, before giving effect to the Amendments, 841,233 shares of our Common Stock remained available for future issuance under the 2014 Plan, summarized as follows:

Summary of Material Features

        The material features of the 2014 Plan are:

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The maximum number of shares of Common Stock to be issued under the 2014 Plan is currently 4,166,666 plus the number of shares of Common Stock underlying any awards under the 2005 Stock Option Plan and the 2006 Stock Option Plan that are forfeited, canceled or terminated (other than by exercise). If the Amendments are approved, the maximum number of shares of Common Stock to be issued under the 2014 Plan will be 10,000,000 plus the number of shares of Common Stock underlying any awards under the Company's 2005 Stock Option Plan and the 2006 Stock Option Plan that are forfeited, canceled or terminated (other than by exercise).



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The shares of Common Stock underlying any awards that are forfeited, canceled, reacquired by the Company prior to vesting, satisfied without any issuance of stock, expire or are otherwise terminated (other than by exercise) under the 2014 Plan are added back to the shares of Common Stock available for issuance under the 2014 Plan.



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Shares tendered or held back for taxes will not be added back to the reserved pool under the 2014 Plan. Upon the exercise of a stock appreciation right, the full number of shares underlying the Award will be charged to the reserved pool. Additionally, shares reacquired by the Company on the open market or otherwise using cash proceeds of option exercises will not be added to the reserved pool.



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The award of stock options (both incentive and non-qualified options), stock appreciation rights, restricted stock, restricted stock units, unrestricted stock, performance shares, dividend equivalent rights and cash-based awards is permitted.



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Without stockholder approval, the exercise price of stock options and stock appreciation rights will not be reduced and stock options and stock appreciation rights will not be otherwise repriced through cancellation in exchange for cash, other awards or stock options or stock appreciation rights with a lower exercise price.



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Any material amendment to the 2014 Plan is subject to approval by our stockholders.



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The 2014 Plan will expire on October 30, 2024, ten (10) years after the date the 2014 Plan was originally approved by the stockholders.

        Based solely on the closing price of our Common Stock as reported by NASDAQ on November 10, 2016, the maximum aggregate market value of Common Stock that could potentially be

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issued under the 2014 Plan if the Amendments are approved is $4,579,828, including the Contingent Option Awards, all other outstanding awards and shares available for future awards. The shares the Company issues under the 2014 Plan will be authorized but unissued shares or treasury shares.

Qualified Performance-Based Compensation under Code Section 162(m)

        To ensure that certain awards granted under the 2014 Plan to a "Covered Employee" (as defined in the Internal Revenue Code of 1986 (the "Code")) qualify as "performance-based compensation" under Section 162(m) of the Code, the 2014 Plan provides that the Compensation Committee may require that the vesting of such awards be conditioned on the satisfaction of performance criteria that may include any or all of the following: (1) total shareholder return, (2) earnings before interest, taxes, depreciation and amortization, (3) net income (loss) (either before or after interest, taxes, depreciation and/or amortization), (4) stock price or changes in the market price of the Common Stock, (5) customer satisfaction indicators, (6) economic value-added, (7) funds from operations or similar measure, (8) sales or revenue, (9) mergers, acquisitions, financing, corporate partnering or strategic transactions, (10) operating income (loss), (11) cash flow (including, but not limited to, operating cash flow and free cash flow), (12) return on capital, assets, equity, or investment, (13) shareholder returns, (14) return on sales, (15) gross or net profit levels, (16) productivity, (17) expenses, (18) margins, (19) operating efficiency, (20) customer satisfaction, (21) working capital, (22) earnings (loss) per share of Common Stock, (23) sales or market shares, (24) number of customers, (25) branding establishment or awareness, (26) technical product development and/or applications advances, (27) commercial, research and development, engineering and/or manufacturing milestones, (28) achievement of corporate collaborative agreement milestones and (29) adjusted EBITDA, any of which may be measured either in absolute terms or as compared to any incremental increase or as compared to results of a peer group. The Compensation Committee will select the particular performance criteria within 90 days following the commencement of a performance cycle.

        Subject to adjustments for stock splits and similar events, the maximum award granted to any one individual that is intended to qualify as "performance-based compensation" under Section 162(m) of the Code currently may not exceed 500,000 shares of Common Stock for any performance cycle, and options or stock appreciation rights with respect to no more than 500,000 shares of Common Stock may be granted to any one individual during any calendar year period. If the Amendments are approved, the maximum award granted to any one individual that is intended to qualify as "performance-based compensation" under Section 162(m) of the Code may not exceed 2,000,000 shares of Common Stock for any performance cycle, and options or stock appreciation rights with respect to no more than 2,000,000 shares of Common Stock may be granted to any one individual during any calendar year period. If a performance-based award is payable in cash, it cannot exceed $10,000,000 for any performance cycle.

Rationale for Amendments

        The 2014 Plan is critical to our ongoing effort to build stockholder value. Our equity incentive program is broad-based and equity incentive awards are an important component of our executive and non-executive employees' compensation. Our Compensation Committee and Board believe we must continue to offer a competitive equity compensation program in order to attract, retain and motivate the talented and qualified employees necessary for our success.

        The Compensation Committee carefully monitors the net burn rate under our 2014 Plan, total dilution, and equity expense in order to maximize stockholder value by granting what it believes are an appropriate number of equity incentive awards to attract, reward, and retain employees. Our compensation philosophy reflects broad-based eligibility for equity incentive awards, and we grant awards to substantially all of our employees. By doing so, we link employee interests with stockholder interests throughout the organization and motivate our employees to act as owners of the business.

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        The Company is completing a strategic restructuring under which Yield10 Bioscience has become its core business, with a focus on developing proprietary technologies to enable step-change improvements in yield for major food and feed crops. In connection with the restructuring, the Company is shifting the balance in employee compensation to increase the use of equity and reduce use of cash for at least the next year. The Board of Directors has also decided to temporarily suspend cash compensation to non-employee directors. The Compensation Committee expects that the payment of cash compensation to non-employee directors will be revisited during the second quarter of 2017 and that equity-based compensation to non-employee directors will be adjusted in light of the suspension of cash compensation. The Amendments are intended to ensure that the Company has the capacity to grant stock options and other equity awards to eligible recipients at levels determined to be appropriate by our Board of Directors and/or our Compensation Committee in order to retain, motivate, and incentivize Company employees, including executive officers and non-employee directors.

        We determined the number of shares reserved for issuance under the 2014 Plan and the limitations on individual grants based on a variety of factors, including the number of shares of Common Stock outstanding, projected equity awards to anticipated new hires, and projected equity awards to non-employee directors.

Summary of the 2014 Plan

        The following description of certain features of the 2014 Plan is intended to be a summary only. The summary is qualified in its entirety by the full text of the 2014 Plan, as amended and restated, that is attached hereto as Appendix A.

        Plan Administration.    The 2014 Plan is administered by the Compensation Committee of our Board of Directors. The Compensation Committee has full power to select, from among the individuals eligible for awards, the individuals to whom awards will be granted, to make any combination of awards to participants, and to determine the specific terms and conditions of each award, subject to the provisions of the 2014 Plan. The Compensation Committee may delegate to our chief executive officer the authority to grant stock options and other awards to employees who are not subject to the reporting and other provisions of Section 16 of the Exchange Act and not subject to Section 162(m) of the Code, subject to certain limitations and guidelines.

        Eligibility.    Persons eligible to participate in the 2014 Plan are those full or part-time officers, employees, non-employee directors and other key persons (including consultants and prospective officers) of the Company and its subsidiaries as selected from time to time by the Compensation Committee in its discretion. As of November 10, 2016, approximately 29 individuals are eligible to participate in the 2014 Plan, including four (4) officers, 20 employees who are not officers, and five (5) non-employee directors.

        Plan Limits.    If the Amendments are approved, the maximum award of stock options or stock appreciation rights granted to any one individual will not exceed 2,000,000 shares of Common Stock (subject to adjustment for stock splits and similar events) for any calendar year period. If any award of restricted stock, restricted stock units or performance shares granted to an individual is intended to qualify as "performance-based compensation" under Section 162(m) of the Code then, if the Amendments are approved, the maximum award shall not exceed 2,000,000 shares of Common Stock (subject to adjustment for stock splits and similar events) to any one such individual in any performance cycle. If any cash-based award is intended to qualify as "performance-based compensation" under Section 162(m) of the Code, then the maximum award to be paid in cash in any performance cycle may not exceed $10,000,000. In addition, if the Amendments are approved, no more than 10,000,000 shares will be issued in the form of incentive stock options.

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        Stock Options.    The 2014 Plan permits the granting of (1) options to purchase Common Stock intended to qualify as incentive stock options under Section 422 of the Code and (2) options that do not so qualify. Options granted under the 2014 Plan will be non-qualified options if they fail to qualify as incentive options or exceed the annual limit on incentive stock options. Incentive stock options may only be granted to employees of the Company and its subsidiaries. Non-qualified options may be granted to any persons eligible to receive incentive options and to non-employee directors and key persons. The option exercise price of each option will be determined by the Compensation Committee but may not be less than 100 percent of the fair market value of the Common Stock on the date of grant. Fair market value for this purpose will be the last reported sale price of the shares of Common Stock on NASDAQ on the date of grant. The exercise price of an option may not be reduced after the date of the option grant, other than to appropriately reflect changes in our capital structure.

        The term of each option will be fixed by the Compensation Committee and may not exceed ten years from the date of grant. The Compensation Committee will determine at what time or times each option may be exercised. Options may be made exercisable in installments and the exercisability of options may be accelerated by the Compensation Committee. In general, unless otherwise permitted by the Compensation Committee, no option granted under the 2014 Plan is transferable by the optionee other than by will or by the laws of descent and distribution, and options may be exercised during the optionee's lifetime only by the optionee, or by the optionee's legal representative or guardian in the case of the optionee's incapacity.

        Upon exercise of options, the option exercise price must be paid in full either in cash, by certified or bank check or other instrument acceptable to the Compensation Committee or by delivery (or attestation to the ownership) of shares of Common Stock that are beneficially owned by the optionee for at least six months or were purchased in the open market. Subject to applicable law, the exercise price may also be delivered to the Company by a broker pursuant to irrevocable instructions to the broker from the optionee. In addition, the Compensation Committee may permit non-qualified options to be exercised using a net exercise feature which reduces the number of shares issued to the optionee by the number of shares with a fair market value equal to the exercise price.

        To qualify as incentive options, options must meet additional federal tax requirements, including a $100,000 limit on the value of shares subject to incentive options that first become exercisable by a participant in any one calendar year.

        Stock Appreciation Rights.    The Compensation Committee may award stock appreciation rights subject to such conditions and restrictions as the Compensation Committee may determine. Stock appreciation rights entitle the recipient to shares of Common Stock equal to the value of the appreciation in the stock price over the exercise price. The exercise price is the fair market value of the Common Stock on the date of grant. The maximum term of a stock appreciation right is ten years.

        Restricted Stock.    The Compensation Committee may award shares of Common Stock to participants subject to such conditions and restrictions as the Compensation Committee may determine. These conditions and restrictions may include the achievement of certain performance goals (as summarized above) and/or continued employment with us through a specified restricted period. However, except in the case of retirement, death, disability or a change of control, in the event these awards granted to employees have a performance-based goal, the restriction period will be at least one year.

        Restricted Stock Units.    The Compensation Committee may award restricted stock units to any participants. Restricted stock units are ultimately payable in the form of shares of Common Stock and may be subject to such conditions and restrictions as the Compensation Committee may determine. These conditions and restrictions may include the achievement of certain performance goals (as summarized above) and/or continued employment with the Company through a specified vesting

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period. However, except in the case of retirement, death, disability or a change of control, in the event these awards granted to employees have a performance-based goal, the restriction period will be at least one year. In the Compensation Committee's sole discretion, it may permit a participant to make an advance election to receive a portion of his or her future cash compensation otherwise due in the form of a deferred stock unit award, subject to the participant's compliance with the procedures established by the Compensation Committee and requirements of Section 409A of the Code. During the deferral period, the deferred stock awards may be credited with dividend equivalent rights.

        Unrestricted Stock Awards.    The Compensation Committee may also grant shares of Common Stock which are free from any restrictions under the 2014 Plan. Unrestricted stock may be granted to any participant in recognition of past services or other valid consideration and may be issued in lieu of cash compensation due to such participant.

        Performance Share Awards.    The Compensation Committee may grant performance share awards to any participant which entitle the recipient to receive shares of Common Stock upon the achievement of certain performance goals (as summarized above) and such other conditions as the Compensation Committee shall determine. Except in the case of retirement, death, disability or a change in control, these awards granted to employees will have a vesting period of at least one year.

        Dividend Equivalent Rights.    The Compensation Committee may grant dividend equivalent rights to participants which entitle the recipient to receive credits for dividends that would be paid if the recipient had held specified shares of Common Stock. Dividend equivalent rights granted as a component of another award subject to performance vesting may be paid only if the related award becomes vested. Dividend equivalent rights may be settled in cash, shares of Common Stock or a combination thereof, in a single installment or installments, as specified in the award.

        Cash-Based Awards.    The Compensation Committee may grant cash bonuses under the 2014 Plan to participants. The cash bonuses may be subject to the achievement of certain performance goals (as summarized above).

        Change of Control Provisions.    The 2014 Plan provides that upon the effectiveness of a "sale event" as defined in the 2014 Plan, all stock options, stock appreciation rights and other awards may be assumed or continued by the successor entity and adjusted accordingly to take into account the impact of the transaction except as otherwise provided by the Compensation Committee in the award agreement. To the extent, however, that the parties to such sale event do not provide for all stock options, stock appreciation rights or any other awards to be so assumed or continued, then such stock options and stock appreciation rights shall become fully vested and exercisable and the restrictions and conditions on all such other awards with time-based conditions will automatically be deemed waived. Awards with conditions and restrictions relating to the attainment of performance goals may become vested and non-forfeitable in connection with a sale event in the Committee's discretion. In addition, in the case of a sale event in which the Company's stockholders will receive cash consideration, the Company may make or provide for a cash payment to participants holding options and stock appreciation rights equal to the difference between the per share cash consideration and the exercise price of the options or stock appreciation rights in exchange for the cancellation thereto.

        Adjustments for Stock Dividends, Stock Splits, Etc.    The 2014 Plan requires the Compensation Committee to make appropriate adjustments to the number of shares of Common Stock that are subject to the 2014 Plan, to certain limits in the 2014 Plan, and to any outstanding awards to reflect stock dividends, stock splits, reverse stock splits, extraordinary cash dividends and similar events.

        Tax Withholding.    Participants in the 2014 Plan are responsible for the payment of any federal, state or local taxes that the Company is required by law to withhold upon the exercise of options or stock appreciation rights or vesting of other awards. Subject to approval by the Compensation

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Committee, participants may elect to have the minimum tax withholding obligations satisfied by authorizing the Company to withhold shares of Common Stock to be issued pursuant to the exercise or vesting of such award.

        Amendments and Termination.    The Board may at any time amend or discontinue the 2014 Plan and the Compensation Committee may at any time amend or cancel any outstanding award for the purpose of satisfying changes in the law or for any other lawful purpose. However, no such action may adversely affect any rights under any outstanding award without the holder's consent. To the extent required under the rules of NASDAQ, any amendments that materially change the terms of the 2014 Plan will be subject to approval by our stockholders. Amendments shall also be subject to approval by our stockholders if and to the extent determined by the Compensation Committee to be required by the Code to preserve the qualified status of incentive options or to ensure that compensation earned under the 2014 Plan qualifies as performance-based compensation under Section 162(m) of the Code.

        Effective Date of the Amendments.    The Board approved the Amendments on October 31, 2016, and the Amendments will become effective on the date they are approved by stockholders. Awards of incentive options may be granted under the 2014 Plan until September 11, 2024. No other awards may be granted under the 2014 Plan after October 30, 2024, the date that is 10 years from the date of stockholder approval of the 2014 Plan.

New Plan Benefits

        Because the grant of awards under the 2014 Plan is within the discretion of the Compensation Committee, the Company cannot determine the dollar value or number of shares of Common Stock that will in the future be received by or allocated to any participant in the 2014 Plan. Accordingly, in lieu of providing information regarding benefits that will be received under the 2014 Plan, the following table provides information concerning the benefits that were received by the following persons and groups during the period from January 1, 2016 through November 10, 2016: our current chief executive officer; each named executive officer; all current executive officers (Oliver P. Peoples, Lynne H. Brum, Charles B. Haaser, and Kristi Snell), as a group; all current directors who are not executive officers, as a group; and all employees who are not executive officers, as a group.

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Tax Aspects Under the Code

        The following is a summary of the principal federal income tax consequences of certain transactions under the 2014 Plan. It does not describe all federal tax consequences under the 2014 Plan, nor does it describe state or local tax consequences.

        Incentive Options.    No taxable income is generally realized by the optionee upon the grant or exercise of an incentive option. If shares of Common Stock issued to an optionee pursuant to the exercise of an incentive option are sold or transferred after two years from the date of grant and after one year from the date of exercise, then (i) upon sale of such shares, any amount realized in excess of the option price (the amount paid for the shares) will be taxed to the optionee as a long-term capital gain, and any loss sustained will be a long-term capital loss, and (ii) the Company will not be entitled to any deduction for federal income tax purposes. The exercise of an incentive option will give rise to an item of tax preference that may result in alternative minimum tax liability for the optionee.

        If shares of Common Stock acquired upon the exercise of an incentive option are disposed of prior to the expiration of the two-year and one-year holding periods described above (a "disqualifying disposition"), generally (i) the optionee will realize ordinary income in the year of disposition in an amount equal to the excess (if any) of the fair market value of the shares of Common Stock at exercise (or, if less, the amount realized on a sale of such shares of Common Stock) over the option price thereof, and (ii) we will be entitled to deduct such amount. Special rules apply where all or a portion of the exercise price of the incentive option is paid by tendering shares of Common Stock.

        If an incentive option is exercised at a time when it no longer qualifies for the tax treatment described above, the option is treated as a non-qualified option. Generally, an incentive option will not be eligible for the tax treatment described above if it is exercised more than three months following termination of employment (or one year in the case of termination of employment by reason of disability). In the case of termination of employment by reason of death, the three-month rule does not apply.

        Non-Qualified Options.    No income is realized by the optionee at the time the option is granted. Generally (i) at exercise, ordinary income is realized by the optionee in an amount equal to the difference between the option price and the fair market value of the shares of Common Stock on the date of exercise, and we receive a tax deduction for the same amount, and (ii) at disposition, appreciation or depreciation after the date of exercise is treated as either short-term or long-term capital gain or loss depending on how long the shares of Common Stock have been held. Special rules apply where all or a portion of the exercise price of the non-qualified option is paid by tendering shares of Common Stock. Upon exercise, the optionee will also be subject to Social Security taxes on the excess of the fair market value over the exercise price of the option.

        Other Awards.    The Company generally will be entitled to a tax deduction in connection with an award under the 2014 Plan in an amount equal to the ordinary income realized by the participant at the time the participant recognizes such income. Participants typically are subject to income tax and recognize such tax at the time that an award is exercised, vests or becomes non-forfeitable, unless the award provides for a further deferral.

        Parachute Payments.    The vesting of any portion of an option or other award that is accelerated due to the occurrence of a change in control (such as a sale event) may cause a portion of the payments with respect to such accelerated awards to be treated as "parachute payments" as defined in the Code. Any such parachute payments may be non-deductible to the Company, in whole or in part, and may subject the recipient to a non-deductible 20 percent federal excise tax on all or a portion of such payment (in addition to other taxes ordinarily payable).

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        Limitation on Deductions.    Under Section 162(m) of the Code, the Company's deduction for certain awards under the 2014 Plan may be limited to the extent that the Chief Executive Officer or other executive officer whose compensation is required to be reported in the summary compensation table (other than the Principal Financial Officer) receives compensation in excess of $1 million a year (other than performance-based compensation that otherwise meets the requirements of Section 162(m) of the Code). The 2014 Plan is structured to allow certain awards to qualify as performance-based compensation.

Burn Rate

        The following table sets forth information regarding historical awards granted and earned for the 2013 through 2015 period, and the corresponding burn rate, which is defined as the number of shares subject to equity-based awards granted in a year divided by the weighted average common shares outstanding for that year, for each of the last three fiscal years:

Vote Required

        The affirmative vote of a majority of shares of Common Stock present in person or represented by proxy at the Special Meeting and entitled to vote on this proposal is required for the approval of the Amendments to the 2014 Plan.

Recommendation

        OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE FOR THE APPROVAL OF THE AMENDMENTS TO THE 2014 STOCK OPTION AND INCENTIVE PLAN.

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SECURITIES AUTHORIZED FOR ISSUANCE UNDER EQUITY COMPENSATION PLANS

        The following table provides information about the Common Stock that may be issued upon the exercise of options, warrants and rights under all the Company's existing equity compensation plans as of December 31, 2015.

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EXECUTIVE COMPENSATION

SUMMARY COMPENSATION TABLE

        The following table summarizes the compensation earned during the years ended December 31, 2015 and 2014 by our "principal executive officer" and the two other most highly paid executive officers who were serving as executive officers on December 31, 2015 (our named executive officers):

Narrative Disclosure to Summary Compensation Table

Base Salaries

        Base salary levels for the named executive officers remained unchanged during 2015 as compared to 2014. Since 2008 there have been no increases in base salaries for the named executive officers other than in connection with promotions.

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Pay for Performance

        Executive bonuses were based on overall corporate performance, to recognize and reward the teamwork of the named executive officers in advancing corporate goals, although the Compensation Committee retains the discretion to adjust individual bonus amounts in exceptional cases. Keeping both base salaries and target bonus percentages unchanged over the years as peer group salaries have risen resulted in cash incentives, as well as base salaries, for our executives being generally below market. Therefore the Compensation Committee increased named executive officer target bonuses to 75% of base salary beginning in 2015.

        In 2015, the Company's corporate goals were to:

•

Execute the Company's biopolymers business strategy;



•

Secure financing;



•

Build a specialty materials business culture; and



•

Maintain focus and manage the Company's cash usage rate.

        In early 2016 the Compensation Committee reviewed corporate performance for 2015 and determined that the Company's successes in manufacturing, cash management and obtaining financing were partially offset by commercial progress that was below expectations. The goal of executing the biopolymers commercial strategy were subjectively weighted more heavily than the other goals. As a result, the committee decided to base 2015 bonuses on an overall Company performance rating of 80%, as compared to 85% for 2014. Bonuses for the named executive officers were determined by applying the 2015 corporate performance rating (80%) to each individual's target bonus amount (75% of the respective base salary).

Long-Term Incentives

        After completing a review of executive equity compensation in March 2015, the Compensation Committee decided to award long-term incentives in 2015 in the form of restricted stock units ("RSUs") rather than stock options, as had been the Company's previous practice. The committee concluded that, under current circumstances, RSUs would provide a stronger incentive and retention tool than stock options. In determining the number of RSUs to be awarded, the committee sought to provide a long-term incentive value for our named executive officers ranging from approximately 85% to 150% of base salary per year. Because no equity incentives were granted to executives during 2014, the 2015 grants were generally twice the annual target amount, adjusted in Mr. Shaulson's case to take into account the equity awards made to him in connection with the commencement of his employment. RSUs vesting in four (4) equal annual installments over a period of four (4) years from the date of grant were awarded as follows:

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OUTSTANDING EQUITY AWARDS AT FISCAL YEAR-END

        The following table summarizes stock option and restricted stock awards held by our named executive officers at December 31, 2015:

Executive Employment Agreements

        Joseph Shaulson.    The Company had an employment contract with Joseph Shaulson, our former chief executive officer, under which Mr. Shaulson was entitled to the following compensation in connection with his service as the president and CEO: an annual base salary of $350,000, subject to increase to $425,000 if the Company achieves certain revenue targets, and an annual cash bonus of up

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to 140% of base salary with a target bonus of no less than 70% of base salary, subject to the achievement of performance goals.

        Pursuant to the terms of Mr. Shaulson's employment agreement, if Mr. Shaulson's employment were to be terminated without cause or for good reason (as defined in the agreement), Mr. Shaulson would be entitled to severance of 1.7 times his base salary, provided that he signed and did not revoke a general release. In addition, the vesting of all unvested equity awards would continue as scheduled, and the exercise period for all equity awards would be extended.

        On October 17, 2016, Mr. Shaulson resigned from his executive responsibilities as president and chief executive officer of the Company. In connection with his departure, on November 4, 2016, Mr. Shaulson and the Company entered into a Separation Agreement as described below (the "Separation Agreement").

        The Separation Agreement provides that Mr. Shaulson will remain an employee and provide transition support to the Company and its management team through the end of 2016. He will also remain on the Company's board of directors. He will continue to receive base compensation and standard employee benefits during the transition period through December 31, 2016. Base compensation was continued at the rate of $350,000 per year through the end of October and then reduced to the rate of $175,000 per year through the end of December. Contemporaneously with the execution of this Separation Agreement, Mr. Shaulson and the Company entered into a Release Agreement, which became effective on November 11, 2016.

        The Separation Agreement provides for the following in lieu of any cash severance and 2016 cash bonus payable under Mr. Shaulson's previous employment agreement:

•

Mr. Shaulson's outstanding non-qualified stock options covering 191,667 shares of Company Common Stock were immediately vested and remain exercisable for the balance of their original term through December 19, 2023.



•

Mr. Shaulson's outstanding restricted stock units covering 151,250 shares of Company Common Stock were immediately vested.



•

Mr. Shaulson was granted new non-qualified stock options under the Company's stock option plan exercisable for a total of 750,000 shares of Company Common Stock. The new options have an exercise price equal to the closing price of the Company's Common Stock on the date of grant, are fully vested and became exercisable on November 11, 2016, the effective date of the Release Agreement, and will be exercisable through December 19, 2023. One of the new options, exercisable for 350,000 of the 750,000 shares of Common Stock, is subject to approval by the Company's stockholders of the Amendments.

        Johan van Walsem.    The Company had an employment agreement with Johan van Walsem, our former chief operating officer, which included minimum salary and target bonus percentage levels and provided that Mr. van Walsem was eligible to receive a performance bonus of up to 150% of his base salary, depending on the Compensation Committee's assessment of achievement of individual and Company goals. Pursuant to the terms of the agreement with Mr. van Walsem, if the Company terminated Mr. van Walsem's employment without "cause" or if he terminated his employment for "good reason" (each, as defined in the agreement), in addition to any accrued obligations, and contingent on the executive's provision of a timely and complete release of claims against the Company, for the period of twelve months following the termination he is entitled to continuation of his base salary and payment of COBRA premiums.

        Oliver P. Peoples.    The Company has an employment agreement with Oliver P. Peoples, the Company's president and chief executive officer. The agreement includes a minimum salary level and provides that Dr. Peoples will be eligible to receive annual bonuses based on individual and Company

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performance. Pursuant to the terms of Dr. Peoples' agreement, if the Company terminates Dr. Peoples' employment without "cause" or if Dr. Peoples terminates his employment for "good reason" (each, as defined in the agreement), he will be entitled to a lump-sum cash payment equal to 24 months' base salary and a pro rata portion of the target bonus for the year in which termination occurs, plus payment of COBRA premiums for 24 months. If the Company terminates Dr. Peoples' employment without cause or if Dr. Peoples terminates his employment for "good reason" within the twenty-four month period immediately following, or the two month period immediately prior to, a "change of control" (as defined in the agreement), in addition to any accrued obligations, and subject to certain conditions, Dr. Peoples will receive: (i) a lump-sum cash payment equal to two times the sum of his then-current base salary plus 50% of his then-current target bonus, (ii) payment of COBRA premiums for 24 months, and (iii) full vesting of his stock options. To the extent Dr. Peoples would be subject to tax under Section 4999 of the Internal Revenue Code as a result of company payments and benefits, the payments and benefits will be reduced if the reduction would maximize his total after-tax payments.

        Noncompetition Agreements.    Mr. Shaulson signed an employee noncompetition, nondisclosure and inventions agreement which prohibits him, during his employment by us and for a period of one year thereafter, from engaging in certain business activities which are directly or indirectly in competition with the products or services being developed, manufactured, marketed, distributed, planned, or sold by the Company during the term of his employment. Each of our other named executive officers has signed an employee noncompetition, nondisclosure and inventions agreement prohibiting the executive, during his or her employment by us and for a period of two years thereafter, from engaging in certain business activities which are directly or indirectly in competition with the products or services being developed, manufactured, marketed, distributed, planned, sold or otherwise provided by us or which are in any way directly or indirectly detrimental to our business.

DIRECTOR COMPENSATION

        The following table summarizes the compensation earned by our non-employee directors in 2015:

Narrative to Director Compensation Table

        Under the Company's policy for compensation of non-employee directors, each non-employee member of our Board of Directors is entitled to an annual retainer of $30,000. In addition, the chairs

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of the Audit Committee, Compensation Committee and Nominating and Corporate Governance Committee are entitled to an additional annual retainer of $15,000, $10,000 and $10,000, respectively. Each non-employee director serving as a member but not chair of our Audit Committee, Compensation Committee and Nominating and Corporate Governance Committee is entitled to an annual retainer of $5,000. In October 2016 our Board of Directors agreed to temporarily suspend cash compensation to non-employee directors.

        In 2015, after a review of the Company's historical equity incentive program for non-employee directors and an informal review of director compensation at selected peer companies, the Board awarded RSUs under the Company's 2014 Stock Option and Incentive Plan to the non-employee directors for the number of shares set forth below:

        These RSUs vested in full on May 28, 2016 (one year after the date of the 2015 annual meeting of stockholders). As of December 31, 2015, our non-employee directors had outstanding stock options and RSUs as follows:

OTHER MATTERS

        The Board of Directors knows of no other matters to be brought before the Special Meeting. If any other matters are properly brought before the Special Meeting, the persons appointed in the accompanying proxy intend to vote the shares represented thereby in accordance with their best judgment on such matters, under applicable laws.

STOCKHOLDER PROPOSALS FOR THE 2017 ANNUAL MEETING

        Any stockholder proposals submitted pursuant to Exchange Act Rule 14a-8 for inclusion in the Company's proxy statement and form of proxy for its 2017 annual meeting must be received by The Company on or before December 20, 2016 in order to be considered for inclusion in its proxy statement and form of proxy. Such proposals must also comply with the requirements as to form and substance established by the SEC if such proposals are to be included in the proxy statement and form of proxy. Any such proposal should be mailed to our principal executive offices: Metabolix, Inc., 19 Presidential Way, Woburn, MA 01801, Attention: Secretary.

        Stockholder proposals to be presented at the Company's 2017 annual meeting, other than stockholder proposals submitted pursuant to Exchange Act Rule 14a-8 for inclusion in the Company's proxy statement and form of proxy for its 2017 annual meeting, must be received in writing at our principal executive office not earlier than January 19, 2017, nor later than February 18, 2017, unless our 2017 annual meeting of stockholders is scheduled to take place before April 19, 2017 or after July 18, 2017. Our By-Laws state that the stockholder must provide timely written notice of such nomination or proposal as well as be present at such meeting, either in person or by a representative. A stockholders' notice shall be timely received by the Company at its principal executive office not less than ninety (90) days nor more than one hundred twenty (120) days prior to the anniversary date of the immediately preceding annual meeting (the "Anniversary Date"); provided, however, that in the event

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the annual meeting is scheduled to be held on a date more than thirty (30) days before the Anniversary Date or more than sixty (60) days after the Anniversary Date, a stockholder's notice shall be timely if received by the Company at its principal executive office not later than the close of business on the later of (a) the ninetieth (90th) day prior to the scheduled date of such annual meeting or (b) the tenth (10th) day following the day on which public announcement of the date of such annual meeting is first made by the Company. Any such proposal should be mailed to: Metabolix, Inc., 19 Presidential Way, Woburn, Massachusetts 01801, Attention: Secretary.

EXPENSES AND SOLICITATION

        The cost of solicitation of proxies will be borne by the Company and, in addition to soliciting stockholders by mail through its regular employees, the Company may request banks, brokers and other custodians, nominees and fiduciaries to solicit their customers who have stock of the Company registered in the names of a nominee and, if so, will reimburse such banks, brokers and other custodians, nominees and fiduciaries for their reasonable out-of-pocket costs. Solicitation by officers and employees of the Company may also be made of some stockholders in person or by mail, telephone or e-mail following the original solicitation.

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Appendix A

METABOLIX, INC.

2014 STOCK OPTION AND INCENTIVE PLAN

As Amended on November 1, 2016 and Restated

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METABOLIX, INC.

2014 STOCK OPTION AND INCENTIVE PLAN

(as amended as of October 31, 2016, and restated)

SECTION 1.    GENERAL PURPOSE OF THE PLAN; DEFINITIONS    

        The name of the plan is the Metabolix, Inc. 2014 Stock Option and Incentive Plan (the "Plan"). The purpose of the Plan is to encourage and enable the officers, employees, Non-Employee Directors and other key persons (including Consultants) of Metabolix, Inc., a Delaware corporation (the "Company"), and its Subsidiaries upon whose judgment, initiative and efforts the Company largely depends for the successful conduct of its business to acquire a proprietary interest in the Company. It is anticipated that providing such persons with a direct stake in the Company's welfare will assure a closer identification of their interests with those of the Company and its stockholders, thereby stimulating their efforts on the Company's behalf and strengthening their desire to remain with the Company.

        The following terms shall be defined as set forth below:

        "Act" means the Securities Act of 1933, as amended, and the rules and regulations thereunder.

        "Administrator" means either the Board or the compensation committee of the Board or a similar committee performing the functions of the compensation committee and which is comprised of not less than two Non-Employee Directors who are independent.

        "Award" or "Awards," except where referring to a particular category of grant under the Plan, shall include Incentive Stock Options, Non-Qualified Stock Options, Stock Appreciation Rights, Restricted Stock Units, Restricted Stock Awards, Unrestricted Stock Awards, Cash-Based Awards, Performance Share Awards and Dividend Equivalent Rights.

        "Award Certificate" means a written or electronic document setting forth the terms and provisions applicable to an Award granted under the Plan. Each Award Certificate is subject to the terms and conditions of the Plan.

        "Board" means the Board of Directors of the Company.

        "Cash-Based Award" means an Award entitling the recipient to receive a cash-denominated payment.

        "Code" means the Internal Revenue Code of 1986, as amended, and any successor Code, and related rules, regulations and interpretations.

        "Consultant" means any natural person that provides bona fide services to the Company, and such services are not in connection with the offer or sale of securities in a capital-raising transaction and do not directly or indirectly promote or maintain a market for the Company's securities.

        "Covered Employee" means an employee who is a "Covered Employee" within the meaning of Section 162(m) of the Code.

        "Dividend Equivalent Right" means an Award entitling the grantee to receive credits based on cash dividends that would have been paid on the shares of Stock specified in the Dividend Equivalent Right (or other award to which it relates) if such shares had been issued to and held by the grantee.

        "Effective Date" means the date on which the Plan is approved by stockholders as set forth in Section 21.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder.

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        "Fair Market Value" of the Stock on any given date means the fair market value of the Stock determined in good faith by the Administrator; provided, however, that if the Stock is admitted to quotation on the National Association of Securities Dealers Automated Quotation System ("NASDAQ"), NASDAQ Global Market or another national securities exchange, the determination shall be made by reference to market quotations. If there are no market quotations for such date, the determination shall be made by reference to the last date preceding such date for which there are market quotations.

        "Incentive Stock Option" means any Stock Option designated and qualified as an "incentive stock option" as defined in Section 422 of the Code.

        "Non-Employee Director" means a member of the Board who is not also an employee of the Company or any Subsidiary.

        "Non-Qualified Stock Option" means any Stock Option that is not an Incentive Stock Option.

        "Option" or "Stock Option" means any option to purchase shares of Stock granted pursuant to Section 5.

        "Performance-Based Award" means any Restricted Stock Award, Restricted Stock Units, Performance Share Award or Cash-Based Award granted to a Covered Employee that is intended to qualify as "performance-based compensation" under Section 162(m) of the Code and the regulations promulgated thereunder.

        "Performance Criteria" means the criteria that the Administrator selects for purposes of establishing the Performance Goal or Performance Goals for an individual for a Performance Cycle. The Performance Criteria (which shall be applicable to the organizational level specified by the Administrator, including, but not limited to, the Company or a unit, division, group, or Subsidiary of the Company) that will be used to establish Performance Goals are limited to the following: total shareholder return, earnings before interest, taxes, depreciation and amortization, net income (loss) (either before or after interest, taxes, depreciation and/or amortization), changes in the market price of the Stock, customer satisfaction indicators, economic value-added, funds from operations or similar measure, sales or revenue, mergers, acquisitions, financing, corporate partnering or strategic transactions, operating income (loss), cash flow (including, but not limited to, operating cash flow and free cash flow), return on capital, assets, equity, or investment, shareholder returns, return on sales, gross or net profit levels, productivity, expense, margins, operating efficiency, customer satisfaction, working capital, earnings (loss) per share of Stock, sales or market shares, number of customers, branding establishment or awareness, technical or product development, advances, research and development and/or engineering milestones, achievement of corporate collaborative agreement milestones and adjusted EBITDA, any of which may be measured either in absolute terms or as compared to any incremental increase or as compared to results of a peer group. The Committee may appropriately adjust any evaluation performance under a Performance Criterion to exclude any of the following events that occurs during a Performance Cycle: (i) asset write-downs or impairments, (ii) litigation or claim judgments or settlements, (iii) the effect of changes in tax law, accounting principles or other such laws or provisions affecting reporting results, (iv) accruals for reorganizations and restructuring programs, (v) any extraordinary non-recurring items, including those described in the Financial Accounting Standards Board's authoritative guidance and/or in management's discussion and analysis of financial condition of operations appearing the Company's annual report to stockholders for the applicable year, and (vi) any other extraordinary items adjusted from the Company U.S. GAAP results.

        "Performance Cycle" means one or more periods of time, which may be of varying and overlapping durations, as the Administrator may select, over which the attainment of one or more Performance Criteria will be measured for the purpose of determining a grantee's right to and the payment of a

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Restricted Stock Award, Restricted Stock Units, Performance Share Award or Cash-Based Award, the vesting and/or payment of which is subject to the attainment of one or more Performance Goals. Each such period shall not be less than 12 months.

        "Performance Goals" means, for a Performance Cycle, the specific goals established in writing by the Administrator for a Performance Cycle based upon the Performance Criteria.

        "Performance Share Award" means an Award entitling the recipient to acquire shares of Stock upon the attainment of specified performance goals.

        "Restricted Shares" means the shares of Stock underlying a Restricted Stock Award that remain subject to a risk of forfeiture or the Company's right of repurchase.

        "Restricted Stock Award" means an Award of Restricted Shares subject to such restrictions and conditions as the Administrator may determine at the time of grant.

        "Restricted Stock Units" means an Award of stock units subject to such restrictions and conditions as the Administrator may determine at the time of grant.

        "Sale Event" shall mean (i) the sale of all or substantially all of the assets of the Company on a consolidated basis to an unrelated person or entity, (ii) a merger, reorganization or consolidation pursuant to which the holders of the Company's outstanding voting power and outstanding stock immediately prior to such transaction do not own a majority of the outstanding voting power and outstanding stock or other equity interests of the resulting or successor entity (or its ultimate parent, if applicable) immediately upon completion of such transaction, (iii) the sale of all of the Stock of the Company to an unrelated person, entity or group thereof acting in concert, or (iv) any other transaction in which the owners of the Company's outstanding voting power immediately prior to such transaction do not own at least a majority of the outstanding voting power of the Company or any successor entity immediately upon completion of the transaction other than as a result of the acquisition of securities directly from the Company.

        "Sale Price" means the value as determined by the Administrator of the consideration payable, or otherwise to be received by stockholders, per share of Stock pursuant to a Sale Event.

        "Section 409A" means Section 409A of the Code and the regulations and other guidance promulgated thereunder.

        "Stock" means the Common Stock, par value $0.01 per share, of the Company, subject to adjustments pursuant to Section 3.

        "Stock Appreciation Right" means an Award entitling the recipient to receive shares of Stock having a value equal to the excess of the Fair Market Value of the Stock on the date of exercise over the exercise price of the Stock Appreciation Right multiplied by the number of shares of Stock with respect to which the Stock Appreciation Right shall have been exercised.

        "Subsidiary" means any corporation or other entity (other than the Company) in which the Company has at least a 50 percent interest, either directly or indirectly.

        "Ten Percent Owner" means an employee who owns or is deemed to own (by reason of the attribution rules of Section 424(d) of the Code) more than 10 percent of the combined voting power of all classes of stock of the Company or any parent or subsidiary corporation.

        "Unrestricted Stock Award" means an Award of shares of Stock free of any restrictions.

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SECTION 2.    ADMINISTRATION OF PLAN; ADMINISTRATOR AUTHORITY TO SELECT GRANTEES AND DETERMINE AWARDS    

        (a)    Administration of Plan.    The Plan shall be administered by the Administrator.

        (b)    Powers of Administrator.    The Administrator shall have the power and authority to grant Awards consistent with the terms of the Plan, including the power and authority:

          (i)  to select the individuals to whom Awards may from time to time be granted;

         (ii)  to determine the time or times of grant, and the extent, if any, of Incentive Stock Options, Non-Qualified Stock Options, Stock Appreciation Rights, Restricted Stock Awards, Restricted Stock Units, Unrestricted Stock Awards, Cash-Based Awards, Performance Share Awards and Dividend Equivalent Rights, or any combination of the foregoing, granted to any one or more grantees;

        (iii)  to determine the number of shares of Stock to be covered by any Award;

        (iv)  to determine and modify from time to time the terms and conditions, including restrictions, not inconsistent with the terms of the Plan, of any Award, which terms and conditions may differ among individual Awards and grantees, and to approve the forms of Award Certificates;

         (v)  to accelerate at any time the exercisability or vesting of all or any portion of any Award in circumstances involving the grantee's death, disability, retirement or termination of employment, or a change in control (including a Sale Event);

        (vi)  subject to the provisions of Section 5(c), to extend at any time the period in which Stock Options may be exercised; and

       (vii)  at any time to adopt, alter and repeal such rules, guidelines and practices for administration of the Plan and for its own acts and proceedings as it shall deem advisable; to interpret the terms and provisions of the Plan and any Award (including related written instruments); to make all determinations it deems advisable for the administration of the Plan; to decide all disputes arising in connection with the Plan; and to otherwise supervise the administration of the Plan.

        All decisions and interpretations of the Administrator shall be binding on all persons, including the Company and Plan grantees.

        (c)    Delegation of Authority to Grant Awards.    Subject to applicable law, the Administrator, in its discretion, may delegate to the Chief Executive Officer of the Company all or part of the Administrator's authority and duties with respect to the granting of Awards to individuals who are (i) not subject to the reporting and other provisions of Section 16 of the Exchange Act and (ii) not Covered Employees. Any such delegation by the Administrator shall include a limitation as to the amount of Stock underlying Awards that may be granted during the period of the delegation and shall contain guidelines as to the determination of the exercise price and the vesting criteria. The Administrator may revoke or amend the terms of a delegation at any time but such action shall not invalidate any prior actions of the Administrator's delegate or delegates that were consistent with the terms of the Plan.

        (d)    Award Certificate.    Awards under the Plan shall be evidenced by Award Certificates that set forth the terms, conditions and limitations for each Award which may include, without limitation, the term of an Award and the provisions applicable in the event employment or service terminates.

        (e)    Indemnification.    Neither the Board nor the Administrator, nor any member of either or any delegate thereof, shall be liable for any act, omission, interpretation, construction or determination made in good faith in connection with the Plan, and the members of the Board and the Administrator

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(and any delegate thereof) shall be entitled in all cases to indemnification and reimbursement by the Company in respect of any claim, loss, damage or expense (including, without limitation, reasonable attorneys' fees) arising or resulting therefrom to the fullest extent permitted by law and/or under the Company's articles or bylaws or any directors' and officers' liability insurance coverage which may be in effect from time to time and/or any indemnification agreement between such individual and the Company.

        (f)    Foreign Award Recipients.    Notwithstanding any provision of the Plan to the contrary, in order to comply with the laws in other countries in which the Company and its Subsidiaries operate or have employees or other individuals eligible for Awards, the Administrator, in its sole discretion, shall have the power and authority to: (i) determine which Subsidiaries shall be covered by the Plan; (ii) determine which individuals outside the United States are eligible to participate in the Plan; (iii) modify the terms and conditions of any Award granted to individuals outside the United States to comply with applicable foreign laws; (iv) establish subplans and modify exercise procedures and other terms and procedures, to the extent the Administrator determines such actions to be necessary or advisable (and such subplans and/or modifications shall be attached to this Plan as appendices); provided, however, that no such subplans and/or modifications shall increase the share limitations contained in Section 3(a) hereof; and (v) take any action, before or after an Award is made, that the Administrator determines to be necessary or advisable to obtain approval or comply with any local governmental regulatory exemptions or approvals. Notwithstanding the foregoing, the Administrator may not take any actions hereunder, and no Awards shall be granted, that would violate the Exchange Act or any other applicable United States securities law, the Code, or any other applicable United States governing statute or law.

SECTION 3.    STOCK ISSUABLE UNDER THE PLAN; MERGERS; SUBSTITUTION    

        (a)    Stock Issuable.    The maximum number of shares of Stock reserved and available for issuance under the Plan shall be (i) 10,000,000 shares plus (ii) the number of shares of Stock underlying any awards under the Metabolix, Inc. 2006 Stock Option and Incentive Plan and the Metabolix, Inc. 2005 Stock Plan that are forfeited, canceled or terminated (other than by exercise) from and after the Effective Date, subject to adjustment as provided in this Section 3. For purposes of this limitation, the shares of Stock underlying any Awards that are forfeited, canceled or otherwise terminated (other than by exercise) shall be added back to the shares of Stock available for issuance under the Plan. Notwithstanding the foregoing, the following shares shall not be added to the shares authorized for grant under the Plan: (i) shares tendered or held back upon exercise of an Option or settlement of an Award to cover the exercise price or tax withholding, and (ii) shares subject to a Stock Appreciation Right that are not issued in connection with the stock settlement of the Stock Appreciation Right upon exercise thereof. In the event the Company repurchases shares of Stock on the open market, such shares shall not be added to the shares of Stock available for issuance under the Plan. Subject to such overall limitations, shares of Stock may be issued up to such maximum number pursuant to any type or types of Award; provided, however, that Stock Options or Stock Appreciation Rights with respect to no more than 2,000,000 shares of Stock, may be granted to any one individual grantee during any one calendar year period. The shares available for issuance under the Plan may be authorized but unissued shares of Stock or shares of Stock reacquired by the Company.

        (b)    Changes in Stock.    Subject to Section 3(c) hereof, if, as a result of any reorganization, recapitalization, reclassification, stock dividend, stock split, reverse stock split or other similar change in the Company's capital stock, the outstanding shares of Stock are increased or decreased or are exchanged for a different number or kind of shares or other securities of the Company, or additional shares or new or different shares or other securities of the Company or other non-cash assets are distributed with respect to such shares of Stock or other securities, or, if, as a result of any merger or consolidation, sale of all or substantially all of the assets of the Company, the outstanding shares of Stock are converted into or exchanged for securities of the Company or any successor entity (or a

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parent or subsidiary thereof), the Administrator shall make an appropriate or proportionate adjustment in (i) the maximum number of shares reserved for issuance under the Plan, including the maximum number of shares that may be issued in the form of Incentive Stock Options, (ii) the number of Stock Options or Stock Appreciation Rights that can be granted to any one individual grantee and the maximum number of shares that may be granted under a Performance-Based Award, (iii) the number and kind of shares or other securities subject to any then outstanding Awards under the Plan, (iv) the repurchase price, if any, per share subject to each outstanding Restricted Stock Award, and (v) the exercise price for each share subject to any then outstanding Stock Options and Stock Appreciation Rights under the Plan, without changing the aggregate exercise price (i.e., the exercise price multiplied by the number of Stock Options and Stock Appreciation Rights) as to which such Stock Options and Stock Appreciation Rights remain exercisable. The Administrator shall also make equitable or proportionate adjustments in the number of shares subject to outstanding Awards and the exercise price and the terms of outstanding Awards to take into consideration cash dividends paid other than in the ordinary course or any other extraordinary corporate event. The adjustment by the Administrator shall be final, binding and conclusive. No fractional shares of Stock shall be issued under the Plan resulting from any such adjustment, but the Administrator in its discretion may make a cash payment in lieu of fractional shares.

        (c)    Mergers and Other Transactions.    In the case of and subject to the consummation of a Sale Event, the parties thereto may cause the assumption or continuation of Awards theretofore granted by the successor entity, or the substitution of such Awards with new Awards of the successor entity or parent thereof, with appropriate adjustment as to the number and kind of shares and, if appropriate, the per share exercise prices, as such parties shall agree. To the extent the parties to such Sale Event do not provide for the assumption, continuation or substitution of Awards, upon the effective time of the Sale Event, the Plan and all outstanding Awards granted hereunder shall terminate. In such case, except as may be otherwise provided in the relevant Award Certificate, all Options and Stock Appreciation Rights that are not exercisable immediately prior to the effective time of the Sale Event shall become fully exercisable as of the effective time of the Sale Event, all other Awards with time-based vesting, conditions or restrictions shall become fully vested and nonforfeitable as of the effective time of the Sale Event, and all Awards with conditions and restrictions relating to the attainment of performance goals may become vested and nonforfeitable in connection with a Sale Event in the Administrator's discretion or to the extent specified in the relevant Award Certificate. In the event of such termination, (i) the Company shall have the option (in its sole discretion) to make or provide for a cash payment to the grantees holding Options and Stock Appreciation Rights, in exchange for the cancellation thereof, in an amount equal to the difference between (A) the Sale Price multiplied by the number of shares of Stock subject to outstanding Options and Stock Appreciation Rights (to the extent then exercisable at prices not in excess of the Sale Price) and (B) the aggregate exercise price of all such outstanding Options and Stock Appreciation Rights; or (ii) each grantee shall be permitted, within a specified period of time prior to the consummation of the Sale Event as determined by the Administrator, to exercise all outstanding Options and Stock Appreciation Rights (to the extent then exercisable) held by such grantee.

        (d)    Substitute Awards.    The Administrator may grant Awards under the Plan in substitution for stock and stock-based awards held by employees, directors or other key persons of another corporation in connection with the merger or consolidation of the employing corporation with the Company or a Subsidiary or the acquisition by the Company or a Subsidiary of property or stock of the employing corporation. The Administrator may direct that the substitute awards be granted on such terms and conditions as the Administrator considers appropriate in the circumstances. Any substitute Awards granted under the Plan shall not count against the share limitation set forth in Section 3(a).

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SECTION 4.    ELIGIBILITY    

        Grantees under the Plan will be such full or part-time officers and other employees, Non-Employee Directors and Consultants of the Company and its Subsidiaries as are selected from time to time by the Administrator in its sole discretion.

SECTION 5.    STOCK OPTIONS    

        (a)    Award of Stock Options.    The Administrator may grant Stock Options under the Plan. Any Stock Option granted under the Plan shall be in such form as the Administrator may from time to time approve.

        Stock Options granted under the Plan may be either Incentive Stock Options or Non-Qualified Stock Options. Incentive Stock Options may be granted only to employees of the Company or any Subsidiary that is a "subsidiary corporation" within the meaning of Section 424(f) of the Code. To the extent that any Option does not qualify as an Incentive Stock Option, it shall be deemed a Non-Qualified Stock Option.

        Stock Options granted pursuant to this Section 5 shall be subject to the following terms and conditions and shall contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Administrator shall deem desirable. If the Administrator so determines, Stock Options may be granted in lieu of cash compensation at the optionee's election, subject to such terms and conditions as the Administrator may establish.

        (b)    Exercise Price.    The exercise price per share for the Stock covered by a Stock Option granted pursuant to this Section 5 shall be determined by the Administrator at the time of grant but shall not be less than 100 percent of the Fair Market Value on the date of grant. In the case of an Incentive Stock Option that is granted to a Ten Percent Owner, the option price of such Incentive Stock Option shall be not less than 110 percent of the Fair Market Value on the grant date.

        (c)    Option Term.    The term of each Stock Option shall be fixed by the Administrator, but no Stock Option shall be exercisable more than ten years after the date the Stock Option is granted. In the case of an Incentive Stock Option that is granted to a Ten Percent Owner, the term of such Stock Option shall be no more than five years from the date of grant.

        (d)    Exercisability; Rights of a Stockholder.    Stock Options shall become exercisable at such time or times, whether or not in installments, as shall be determined by the Administrator at or after the grant date. The Administrator may at any time accelerate the exercisability of all or any portion of any Stock Option. An optionee shall have the rights of a stockholder only as to shares acquired upon the exercise of a Stock Option and not as to unexercised Stock Options.

        (e)    Method of Exercise.    Stock Options may be exercised in whole or in part, by giving written or electronic notice of exercise to the Company, specifying the number of shares to be purchased. Payment of the purchase price may be made by one or more of the following methods except to the extent otherwise provided in the Option Award Certificate:

          (i)  In cash, by certified or bank check or other instrument acceptable to the Administrator;

         (ii)  Through the delivery (or attestation to the ownership following such procedures as the Administrator may prescribe) of shares of Stock that are not then subject to restrictions under any Company plan. Such surrendered shares shall be valued at Fair Market Value on the exercise date;

        (iii)  By the optionee delivering to the Company a properly executed exercise notice together with irrevocable instructions to a broker to promptly deliver to the Company cash or a check payable and acceptable to the Company for the purchase price; provided that in the event the optionee chooses to pay the purchase price as so provided, the optionee and the broker shall comply with such procedures and enter into such agreements of indemnity and other agreements as the Administrator shall prescribe as a condition of such payment procedure; or

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        (iv)  With respect to Stock Options that are not Incentive Stock Options, by a "net exercise" arrangement pursuant to which the Company will reduce the number of shares of Stock issuable upon exercise by the largest whole number of shares with a Fair Market Value that does not exceed the aggregate exercise price.

Payment instruments will be received subject to collection. The transfer to the optionee on the records of the Company or of the transfer agent of the shares of Stock to be purchased pursuant to the exercise of a Stock Option will be contingent upon receipt from the optionee (or a purchaser acting in his stead in accordance with the provisions of the Stock Option) by the Company of the full purchase price for such shares and the fulfillment of any other requirements contained in the Option Award Certificate or applicable provisions of laws (including the satisfaction of any withholding taxes that the Company is obligated to withhold with respect to the optionee). In the event an optionee chooses to pay the purchase price by previously-owned shares of Stock through the attestation method, the number of shares of Stock transferred to the optionee upon the exercise of the Stock Option shall be net of the number of attested shares. In the event that the Company establishes, for itself or using the services of a third party, an automated system for the exercise of Stock Options, such as a system using an internet website or interactive voice response, then the paperless exercise of Stock Options may be permitted through the use of such an automated system.

        (f)    Auto Exercise at Expiration.    The Company may provide in an Award Agreement that to the extent the Option remains unexercised, it will be exercised automatically by "net exercise" pursuant to Section 5(e)(iv) of the Plan immediately prior to the end of the Option Term.

        (g)    Annual Limit on Incentive Stock Options.    To the extent required for "incentive stock option" treatment under Section 422 of the Code, the aggregate Fair Market Value (determined as of the time of grant) of the shares of Stock with respect to which Incentive Stock Options granted under this Plan and any other plan of the Company or its parent and subsidiary corporations become exercisable for the first time by an optionee during any calendar year shall not exceed $100,000. To the extent that any Stock Option exceeds this limit, it shall constitute a Non-Qualified Stock Option.

SECTION 6.    STOCK APPRECIATION RIGHTS    

        (a)    Award of Stock Appreciation Rights.    The Administrator may grant Stock Appreciation Rights under the Plan. A Stock Appreciation Right is an Award entitling the recipient to receive shares of Stock having a value equal to the excess of the Fair Market Value of a share of Stock on the date of exercise over the exercise price of the Stock Appreciation Right multiplied by the number of shares of Stock with respect to which the Stock Appreciation Right shall have been exercised.

        (b)    Exercise Price of Stock Appreciation Rights.    The exercise price of a Stock Appreciation Right shall not be less than 100 percent of the Fair Market Value of the Stock on the date of grant.

        (c)    Grant and Exercise of Stock Appreciation Rights.    Stock Appreciation Rights may be granted by the Administrator independently of any Stock Option granted pursuant to Section 5 of the Plan.

        (d)    Terms and Conditions of Stock Appreciation Rights.    Stock Appreciation Rights shall be subject to such terms and conditions as shall be determined from time to time by the Administrator. The term of a Stock Appreciation Right may not exceed ten years.

SECTION 7.    RESTRICTED STOCK AWARDS    

        (a)    Nature of Restricted Stock Awards.    The Administrator may grant Restricted Stock Awards under the Plan. A Restricted Stock Award is any Award of Restricted Shares subject to such restrictions and conditions as the Administrator may determine at the time of grant. Conditions may be based on continuing employment (or other service relationship) and/or achievement of pre-established performance goals and objectives. The terms and conditions of each such Award Certificate shall be

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determined by the Administrator, and such terms and conditions may differ among individual Awards and grantees.

        (b)    Rights as a Stockholder.    Upon the grant of the Restricted Stock Award and payment of any applicable purchase price, a grantee shall have the rights of a stockholder with respect to the voting of the Restricted Shares and receipt of dividends; provided that if the lapse of restrictions with respect to the Restricted Stock Award is tied to the attainment of performance goals, any dividends paid by the Company during the performance period shall accrue and shall not be paid to the grantee until and to the extent the performance goals are met with respect to the Restricted Stock Award. Unless the Administrator shall otherwise determine, (i) uncertificated Restricted Shares shall be accompanied by a notation on the records of the Company or the transfer agent to the effect that they are subject to forfeiture until such Restricted Shares are vested as provided in Section 7(d) below, and (ii) certificated Restricted Shares shall remain in the possession of the Company until such Restricted Shares are vested as provided in Section 7(d) below, and the grantee shall be required, as a condition of the grant, to deliver to the Company such instruments of transfer as the Administrator may prescribe.

        (c)    Restrictions.    Restricted Shares may not be sold, assigned, transferred, pledged or otherwise encumbered or disposed of except as specifically provided herein or in the Restricted Stock Award Certificate. Except as may otherwise be provided by the Administrator either in the Award Certificate or, subject to Section 18 below, in writing after the Award is issued, if a grantee's employment (or other service relationship) with the Company and its Subsidiaries terminates for any reason, any Restricted Shares that have not vested at the time of termination shall automatically and without any requirement of notice to such grantee from or other action by or on behalf of, the Company be deemed to have been reacquired by the Company at its original purchase price (if any) from such grantee or such grantee's legal representative simultaneously with such termination of employment (or other service relationship), and thereafter shall cease to represent any ownership of the Company by the grantee or rights of the grantee as a stockholder. Following such deemed reacquisition of Restricted Shares that are represented by physical certificates, a grantee shall surrender such certificates to the Company upon request without consideration.

        (d)    Vesting of Restricted Shares.    The Administrator at the time of grant shall specify the date or dates and/or the attainment of pre-established performance goals, objectives and other conditions on which the non-transferability of the Restricted Shares and the Company's right of repurchase or forfeiture shall lapse. Subsequent to such date or dates and/or the attainment of such pre-established performance goals, objectives and other conditions, the shares on which all restrictions have lapsed shall no longer be Restricted Shares and shall be deemed "vested."

SECTION 8.    RESTRICTED STOCK UNITS    

        (a)    Nature of Restricted Stock Units.    The Administrator may grant Restricted Stock Units under the Plan. A Restricted Stock Unit is an Award of stock units that may be settled in shares of Stock upon the satisfaction of such restrictions and conditions at the time of grant. Conditions may be based on continuing employment (or other service relationship) and/or achievement of pre-established performance goals and objectives. The terms and conditions of each such Award Certificate shall be determined by the Administrator, and such terms and conditions may differ among individual Awards and grantees. Except in the case of Restricted Stock Units with a deferred settlement date that complies with Section 409A, at the end of the vesting period, the Restricted Stock Units, to the extent vested, shall be settled in the form of shares of Stock. Restricted Stock Units with deferred settlement dates are subject to Section 409A and shall contain such additional terms and conditions as the Administrator shall determine in its sole discretion in order to comply with the requirements of Section 409A.

        (b)    Election to Receive Restricted Stock Units in Lieu of Compensation.    The Administrator may, in its sole discretion, permit a grantee to elect to receive a portion of future cash compensation

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otherwise due to such grantee in the form of an award of Restricted Stock Units. Any such election shall be made in writing and shall be delivered to the Company no later than the date specified by the Administrator and in accordance with Section 409A and such other rules and procedures established by the Administrator. Any such future cash compensation that the grantee elects to defer shall be converted to a fixed number of Restricted Stock Units based on the Fair Market Value of Stock on the date the compensation would otherwise have been paid to the grantee if such payment had not been deferred as provided herein. The Administrator shall have the sole right to determine whether and under what circumstances to permit such elections and to impose such limitations and other terms and conditions thereon as the Administrator deems appropriate. Any Restricted Stock Units that are elected to be received in lieu of cash compensation shall be fully vested, unless otherwise provided in the Award Certificate.

        (c)    Rights as a Stockholder.    A grantee shall have the rights as a stockholder only as to shares of Stock acquired by the grantee upon settlement of Restricted Stock Units; provided, however, that the grantee may be credited with Dividend Equivalent Rights with respect to the stock units underlying his Restricted Stock Units, subject to the provisions of Section 11 and such terms and conditions as the Administrator may determine.

        (d)    Termination.    Except as may otherwise be provided by the Administrator either in the Award Certificate or, subject to Section 18 below, in writing after the Award is issued, a grantee's right in all Restricted Stock Units that have not vested shall automatically terminate upon the grantee's termination of employment (or cessation of service relationship) with the Company and its Subsidiaries for any reason.

SECTION 9.    UNRESTRICTED STOCK AWARDS    

        Grant or Sale of Unrestricted Stock.    The Administrator may grant (or sell at par value or such higher purchase price determined by the Administrator) an Unrestricted Stock Award under the Plan. An Unrestricted Stock Award is an Award pursuant to which the grantee may receive shares of Stock free of any restrictions under the Plan. Unrestricted Stock Awards may be granted in respect of past services or other valid consideration, or in lieu of cash compensation due to such grantee.

SECTION 10.    CASH-BASED AWARDS    

        Grant of Cash-Based Awards.    The Administrator may grant Cash-Based Awards under the Plan. A Cash-Based Award is an Award that entitles the grantee to a payment in cash upon the attainment of specified Performance Goals. The Administrator shall determine the maximum duration of the Cash-Based Award, the amount of cash to which the Cash-Based Award pertains, the conditions upon which the Cash-Based Award shall become vested or payable, and such other provisions as the Administrator shall determine. Each Cash-Based Award shall specify a cash-denominated payment amount, formula or payment ranges as determined by the Administrator. Payment, if any, with respect to a Cash-Based Award shall be made in accordance with the terms of the Award and may be made in cash.

SECTION 11.    PERFORMANCE SHARE AWARDS    

        (a)    Nature of Performance Share Awards.    The Administrator may grant Performance Share Awards under the Plan. A Performance Share Award is an Award entitling the grantee to receive shares of Stock upon the attainment of performance goals. The Administrator shall determine whether and to whom Performance Share Awards shall be granted, the performance goals, the periods during which performance is to be measured, which may not be less than one year except in the case of a Sale Event, and such other limitations and conditions as the Administrator shall determine.

        (b)    Rights as a Stockholder.    A grantee receiving a Performance Share Award shall have the rights of a stockholder only as to shares of Stock actually received by the grantee under the Plan and

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not with respect to shares subject to the Award but not actually received by the grantee. A grantee shall be entitled to receive shares of Stock under a Performance Share Award only upon satisfaction of all conditions specified in the Performance Share Award Certificate (or in a performance plan adopted by the Administrator).

        (c)    Termination.    Except as may otherwise be provided by the Administrator either in the Award agreement or, subject to Section 18 below, in writing after the Award is issued, a grantee's rights in all Performance Share Awards shall automatically terminate upon the grantee's termination of employment (or cessation of service relationship) with the Company and its Subsidiaries for any reason.

SECTION 12.    PERFORMANCE-BASED AWARDS TO COVERED EMPLOYEES    

        (a)    Performance-Based Awards.    The Administrator may grant one or more Performance-Based Awards in the form of a Restricted Stock Award, Restricted Stock Units, Performance Share Awards or Cash-Based Award payable upon the attainment of Performance Goals that are established by the Administrator and relate to one or more of the Performance Criteria, in each case on a specified date or dates or over any period or periods determined by the Administrator. The Administrator shall define in an objective fashion the manner of calculating the Performance Criteria it selects to use for any Performance Cycle. Depending on the Performance Criteria used to establish such Performance Goals, the Performance Goals may be expressed in terms of overall Company performance or the performance of a division, business unit, or an individual. Each Performance-Based Award shall comply with the provisions set forth below.

        (b)    Grant of Performance-Based Awards.    With respect to each Performance-Based Award granted to a Covered Employee, the Administrator shall select, within the first 90 days of a Performance Cycle (or, if shorter, within the maximum period allowed under Section 162(m) of the Code) the Performance Criteria for such grant, and the Performance Goals with respect to each Performance Criterion (including a threshold level of performance below which no amount will become payable with respect to such Award). Each Performance-Based Award will specify the amount payable, or the formula for determining the amount payable, upon achievement of the various applicable performance targets. The Performance Criteria established by the Administrator may be (but need not be) different for each Performance Cycle and different Performance Goals may be applicable to Performance-Based Awards to different Covered Employees.

        (c)    Payment of Performance-Based Awards.    Following the completion of a Performance Cycle, the Administrator shall meet to review and certify in writing whether, and to what extent, the Performance Goals for the Performance Cycle have been achieved and, if so, to also calculate and certify in writing the amount of the Performance-Based Awards earned for the Performance Cycle. The Administrator shall then determine the actual size of each Covered Employee's Performance-Based Award.

        (d)    Maximum Award Payable.    The maximum Performance-Based Award payable to any one Covered Employee under the Plan for a Performance Cycle is 2,000,000 shares of Stock (subject to adjustment as provided in Section 3(b) hereof) or $10,000,000 in the case of a Performance-Based Award that is a Cash-Based Award.

SECTION 13.    DIVIDEND EQUIVALENT RIGHTS    

        (a)    Dividend Equivalent Rights.    The Administrator may grant Dividend Equivalent Rights under the Plan. A Dividend Equivalent Right is an Award entitling the grantee to receive credits based on cash dividends that would have been paid on the shares of Stock specified in the Dividend Equivalent Right (or other Award to which it relates) if such shares had been issued to the grantee. A Dividend Equivalent Right may be granted hereunder to any grantee as a component of an award of Restricted Stock Units, Restricted Stock Award or Performance Share Award or as a freestanding award. The terms and conditions of Dividend Equivalent Rights shall be specified in the Award Certificate. Dividend equivalents credited to the holder of a Dividend Equivalent Right may be paid currently or

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may be deemed to be reinvested in additional shares of Stock, which may thereafter accrue additional equivalents. Any such reinvestment shall be at Fair Market Value on the date of reinvestment or such other price as may then apply under a dividend reinvestment plan sponsored by the Company, if any. Dividend Equivalent Rights may be settled in cash or shares of Stock or a combination thereof, in a single installment or installments. A Dividend Equivalent Right granted as a component of an Award of Restricted Stock Units or Performance Share Award shall provide that such Dividend Equivalent Right shall be settled only upon settlement or payment of, or lapse of restrictions on, such other Award, and that such Dividend Equivalent Right shall expire or be forfeited or annulled under the same conditions as such other Award.

        (b)    Termination.    Except as may otherwise be provided by the Administrator either in the Award Certificate or, subject to Section 18 below, in writing after the Award is issued, a grantee's rights in all Dividend Equivalent Rights shall automatically terminate upon the grantee's termination of employment (or cessation of service relationship) with the Company and its Subsidiaries for any reason.

SECTION 14.    TRANSFERABILITY OF AWARDS    

        (a)    Transferability.    Except as provided in Section 14(b) below, during a grantee's lifetime, his or her Awards shall be exercisable only by the grantee, or by the grantee's legal representative or guardian in the event of the grantee's incapacity. No Awards shall be sold, assigned, transferred or otherwise encumbered or disposed of by a grantee other than by will or by the laws of descent and distribution or pursuant to a domestic relations order. No Awards shall be subject, in whole or in part, to attachment, execution, or levy of any kind, and any purported transfer in violation hereof shall be null and void.

        (b)    Administrator Action.    Notwithstanding Section 14(a), the Administrator, in its discretion, may provide either in the Award Certificate regarding a given Award or by subsequent written approval that the grantee (who is an employee or director) may transfer his or her Non-Qualified Options to his or her immediate family members, to trusts for the benefit of such family members, or to partnerships in which such family members are the only partners, provided that the transferee agrees in writing with the Company to be bound by all of the terms and conditions of this Plan and the applicable Award. In no event may an Award be transferred by a grantee for value.

        (c)    Family Member.    For purposes of Section 14(b), "family member" shall mean a grantee's child, stepchild, grandchild, parent, stepparent, grandparent, spouse, former spouse, sibling, niece, nephew, mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or sister-in-law, including adoptive relationships, any person sharing the grantee's household (other than a tenant of the grantee), a trust in which these persons (or the grantee) have more than 50 percent of the beneficial interest, a foundation in which these persons (or the grantee) control the management of assets, and any other entity in which these persons (or the grantee) own more than 50 percent of the voting interests.

        (d)    Designation of Beneficiary.    To the extent permitted by the Company, each grantee to whom an Award has been made under the Plan may designate a beneficiary or beneficiaries to exercise any Award or receive any payment under any Award payable on or after the grantee's death. Any such designation shall be on a form provided for that purpose by the Administrator and shall not be effective until received by the Administrator. If no beneficiary has been designated by a deceased grantee, or if the designated beneficiaries have predeceased the grantee, the beneficiary shall be the grantee's estate.

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SECTION 15.    TAX WITHHOLDING    

        (a)    Payment by Grantee.    Each grantee shall, no later than the date as of which the value of an Award or of any Stock or other amounts received thereunder first becomes includable in the gross income of the grantee for Federal income tax purposes, pay to the Company, or make arrangements satisfactory to the Administrator regarding payment of, any Federal, state, or local taxes of any kind required by law to be withheld by the Company with respect to such income. The Company and its Subsidiaries shall, to the extent permitted by law, have the right to deduct any such taxes from any payment of any kind otherwise due to the grantee. The Company's obligation to deliver evidence of book entry (or stock certificates) to any grantee is subject to and conditioned on tax withholding obligations being satisfied by the grantee.

        (b)    Payment in Stock.    Subject to approval by the Administrator, a grantee may elect to have the Company's minimum required tax withholding obligation satisfied, in whole or in part, by authorizing the Company to withhold from shares of Stock to be issued pursuant to any Award a number of shares with an aggregate Fair Market Value (as of the date the withholding is effected) that would satisfy the withholding amount due. The Administrator may also require Awards to be subject to mandatory share withholding up to the required withholding amount. For purposes of share withholding, the Fair Market Value of withheld shares shall be determined in the same manner as the value of Stock includible in income of the Participants.

SECTION 16.    SECTION 409A AWARDS    

        To the extent that any Award is determined to constitute "nonqualified deferred compensation" within the meaning of Section 409A (a "409A Award"), the Award shall be subject to such additional rules and requirements as specified by the Administrator from time to time in order to comply with Section 409A. In this regard, if any amount under a 409A Award is payable upon a "separation from service" (within the meaning of Section 409A) to a grantee who is then considered a "specified employee" (within the meaning of Section 409A), then no such payment shall be made prior to the date that is the earlier of (i) six months and one day after the grantee's separation from service, or (ii) the grantee's death, but only to the extent such delay is necessary to prevent such payment from being subject to interest, penalties and/or additional tax imposed pursuant to Section 409A. Further, the settlement of any such Award may not be accelerated except to the extent permitted by Section 409A.

SECTION 17.    TERMINATION OF EMPLOYMENT, TRANSFER, LEAVE OF ABSENCE, ETC.    

        (a)    Termination of Employment.    If the grantee's employer ceases to be a Subsidiary, the grantee shall be deemed to have terminated employment for purposes of the Plan.

        (b)   For purposes of the Plan, the following events shall not be deemed a termination of employment:

          (i)  a transfer to the employment of the Company from a Subsidiary or from the Company to a Subsidiary, or from one Subsidiary to another; or

         (ii)  an approved leave of absence for military service or sickness, or for any other purpose approved by the Company, if the employee's right to re-employment is guaranteed either by a statute or by contract or under the policy pursuant to which the leave of absence was granted or if the Administrator otherwise so provides in writing.

SECTION 18.    AMENDMENTS AND TERMINATION    

        The Board may, at any time, amend or discontinue the Plan and the Administrator may, at any time, amend or cancel any outstanding Award for the purpose of satisfying changes in law or for any other lawful purpose, but no such action shall adversely affect rights under any outstanding Award without the holder's consent. Except as provided in Section 3(c) or 3(d), without prior stockholder

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approval, in no event may the Administrator exercise its discretion to reduce the exercise price of outstanding Stock Options or Stock Appreciation Rights or effect repricing through cancellation and re-grants or cancellation of Stock Options or Stock Appreciation Rights in exchange for cash. To the extent required under the rules of any securities exchange or market system on which the Stock is listed, to the extent determined by the Administrator to be required by the Code to ensure that Incentive Stock Options granted under the Plan are qualified under Section 422 of the Code, or to ensure that compensation earned under Awards qualifies as performance-based compensation under Section 162(m) of the Code, Plan amendments shall be subject to approval by the Company stockholders entitled to vote at a meeting of stockholders. Nothing in this Section 18 shall limit the Administrator's authority to take any action permitted pursuant to Section 3(b) or 3(c).

SECTION 19.    STATUS OF PLAN    

        With respect to the portion of any Award that has not been exercised and any payments in cash, Stock or other consideration not received by a grantee, a grantee shall have no rights greater than those of a general creditor of the Company unless the Administrator shall otherwise expressly determine in connection with any Award or Awards. In its sole discretion, the Administrator may authorize the creation of trusts or other arrangements to meet the Company's obligations to deliver Stock or make payments with respect to Awards hereunder, provided that the existence of such trusts or other arrangements is consistent with the foregoing sentence.

SECTION 20.    GENERAL PROVISIONS    

        (a)    No Distribution.    The Administrator may require each person acquiring Stock pursuant to an Award to represent to and agree with the Company in writing that such person is acquiring the shares without a view to distribution thereof.

        (b)    Delivery of Stock Certificates.    Stock certificates to grantees under this Plan shall be deemed delivered for all purposes when the Company or a stock transfer agent of the Company shall have mailed such certificates in the United States mail, addressed to the grantee, at the grantee's last known address on file with the Company. Uncertificated Stock shall be deemed delivered for all purposes when the Company or a Stock transfer agent of the Company shall have given to the grantee by electronic mail (with proof of receipt) or by United States mail, addressed to the grantee, at the grantee's last known address on file with the Company, notice of issuance and recorded the issuance in its records (which may include electronic "book entry" records). Notwithstanding anything herein to the contrary, the Company shall not be required to issue or deliver any certificates evidencing shares of Stock pursuant to the exercise of any Award, unless and until the Administrator has determined, with advice of counsel (to the extent the Administrator deems such advice necessary or advisable), that the issuance and delivery of such certificates is in compliance with all applicable laws, regulations of governmental authorities and, if applicable, the requirements of any exchange on which the shares of Stock are listed, quoted or traded. All Stock certificates delivered pursuant to the Plan shall be subject to any stop-transfer orders and other restrictions as the Administrator deems necessary or advisable to comply with federal, state or foreign jurisdiction, securities or other laws, rules and quotation system on which the Stock is listed, quoted or traded. The Administrator may place legends on any Stock certificate to reference restrictions applicable to the Stock. In addition to the terms and conditions provided herein, the Administrator may require that an individual make such reasonable covenants, agreements, and representations as the Administrator, in its discretion, deems necessary or advisable in order to comply with any such laws, regulations, or requirements. The Administrator shall have the right to require any individual to comply with any timing or other restrictions with respect to the settlement or exercise of any Award, including a window-period limitation, as may be imposed in the discretion of the Administrator.

        (c)    Stockholder Rights.    Until Stock is deemed delivered in accordance with Section 20(b), no right to vote or receive dividends or any other rights of a stockholder will exist with respect to shares of

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Stock to be issued in connection with an Award, notwithstanding the exercise of a Stock Option or any other action by the grantee with respect to an Award.

        (d)    Other Compensation Arrangements; No Employment Rights.    Nothing contained in this Plan shall prevent the Board from adopting other or additional compensation arrangements, including trusts, and such arrangements may be either generally applicable or applicable only in specific cases. The adoption of this Plan and the grant of Awards do not confer upon any employee any right to continued employment with the Company or any Subsidiary.

        (e)    Trading Policy Restrictions.    Option exercises and other Awards under the Plan shall be subject to the Company's insider trading policies and procedures, as in effect from time to time.

        (f)    Clawback Policy.    Awards under the Plan shall be subject to the Company's clawback policy, as in effect from time to time.

SECTION 21.    EFFECTIVE DATE OF PLAN    

        This Plan shall become effective on the Effective Date upon stockholder approval of the Plan in accordance with applicable state law, the Company's bylaws and articles of incorporation, and applicable stock exchange rules or pursuant to written consent. No grants of Stock Options and other Awards may be made hereunder after the tenth anniversary of the Effective Date and no grants of Incentive Stock Options may be made hereunder after the tenth anniversary of the date the Plan is approved by the Board.

SECTION 22.    GOVERNING LAW    

        This Plan and all Awards and actions taken thereunder shall be governed by, and construed in accordance with, the laws of the State of Delaware, applied without regard to conflict of law principles.

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METABOLIX, INC. 19 Presidential Way Woburn, Massachusetts 01801 (617) 583-1700 NOTICE OF SPECIAL MEETING OF STOCKHOLDERS TO BE HELD ON DECEMBER 21, 2016
METABOLIX, INC. 19 Presidential Way Woburn, MA 01801 PROXY STATEMENT For the Special Meeting of Stockholders To Be Held on December 21, 2016 November 21, 2016
VOTING
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT
PROPOSAL 1 AMENDMENTS TO THE METABOLIX, INC. 2014 STOCK OPTION AND INCENTIVE PLAN
SECURITIES AUTHORIZED FOR ISSUANCE UNDER EQUITY COMPENSATION PLANS
EXECUTIVE COMPENSATION SUMMARY COMPENSATION TABLE
OUTSTANDING EQUITY AWARDS AT FISCAL YEAR-END
DIRECTOR COMPENSATION
OTHER MATTERS
STOCKHOLDER PROPOSALS FOR THE 2017 ANNUAL MEETING
EXPENSES AND SOLICITATION
METABOLIX, INC. 2014 STOCK OPTION AND INCENTIVE PLAN (as amended as of October 31, 2016, and restated)