**1. ****Warrant Term****.**The purchase rights represented by this Warrant areexercisable, in whole or in part, at any time and from time to time, from and after the Warrantgrant date and on or prior to the earlier of (i) **[IMPORT EXPIRATION TIME]**or (ii) the fourth(4th) anniversary following the consummation of a QPO (such earlier date being the“**Expiration Time**”).     **2. ****Exercise of Warrant; Payment of Taxes****.**          **2.1****Exercise of Warrant****.**The purchase rights represented by this Warrant may beexercised by the Warrantholder, in whole or in part and from time to time, by the surrender of thisWarrant (with a duly executed notice of exercise form, the “Exercise Form”, in the form attachedhereto as Exhibit A) at the principal office of the Company and by the payment to theCompany of an amount equal to the then applicable Exercise Price per share multiplied by the numberof Warrant Shares then being purchased. If the Warrantholder is not already a party thereto, theWarrantholder shall also execute, upon request from the Company, a joinder agreement as an Investorto the Stockholders’ Agreement, as amended and restated, such joinder agreement to be in form andsubstance mutually agreeable to both the Warrantholder and the Company. The Warrantholder shall bedeemed to have become the holder(s) of record of, and shall be treated for all purposes as therecord holder(s) of, the Warrant Shares represented thereby (and such Warrant Shares shall bedeemed to have been issued) immediately prior to the close of business on the date or dates uponwhich this Warrant is exercised.          **2.2****Net Exercise****.**          (a) In lieu of payment in cash, the rights represented by this Warrant may also beexercised at any time by a written notice of exercise in the form of Exhibit A attachedhereto, providing for the net exercise of this Warrant for the Warrant Shares equal to the value(as determined below) of this Warrant (or the portion thereof being exercised), specifying thatthis net exercise election has been made, and the net number of Warrant Shares to be issued aftergiving effect to such net exercise. In the event the Warrantholder makes such election, Companyshall issue to the Warrantholder a number of Warrant Shares computed using the following formula:     X = Y(A-B)         AWhere:X = the number of Warrant Shares to be issued to the WarrantholderY = the number of Warrant Shares purchasable under the Warrant or, if only a portion of the Warrantis being exercised, the portion of the Warrant being exercised (as of the date of such netexercise)A = the Fair Market Value of one Share of Common Stock (as of the date of such net exercise)B = Exercise Price of one Share of Common Stock (as adjusted to the date of such net exercise)
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          (b) For purposes of this Section 2.2, the “**Fair Market Value**” of one shareof the Company’s Common Stock shall be equal to either (i) if the exercise of this Warrant occursin connection with an initial public offering of the Company, then the Fair Market Value shall beequal to the “initial price to public” specified in the final prospectus with respect to theinitial public offering, or (ii) if the exercise of this Warrant occurs after an initial publicoffering of the Company but not in connection therewith, then the Fair Market Value shall be equalto the average of the closing price(s) of the Company’s Common Stock as quoted over the counter oron any exchange on which the Common Stock is listed as such closing prices are published in TheWall Street Journal for the fifteen (15) trading days (or such lesser number of trading days asthe stock may have been actually trading) ending on the day prior to the date of determination ofFair Market Value. Notwithstanding the foregoing, if the Warrant is exercised in connection with amerger or sale of all or substantially all of the Company’s assets, Fair Market Value shall meanthe value that would have been allocable to or received in respect of a Warrant Share had theWarrant been exercised prior to such merger or sale. If the Common Stock is not traded Over The Counter or on an exchange, or if the Warrant is notexercised in connection with a merger or sale of all or substantially all of its assets, then theFair Market Value shall be reasonably determined in good faith by the Board of Directors. If theWarrantholder hereof does not agree with the determination of Fair Market Value as determined bythe Board of Directors, the Company and the Warrantholder hereof shall negotiate an appropriateFair Market Value. If after ten (10) days, the Company and the Warrantholder cannot agree, thenthe Warrantholder may request that the Fair Market Value be determined by an investment banker ofnational reputation selected by the Company and reasonably acceptable to the Warrantholder. Thefees and expenses of such investment banker shall be borne by the Company unless the Fair MarketValue determined by such investment banker is equal to or less than the Fair Market Value asdetermined by the Company, in which event the fees and expenses of such investment banker shall beborne by the Warrantholder hereof.          **2.3****Automatic Exercise.** Immediately before the expiration or termination of thisWarrant, to the extent this Warrant is not previously exercised, and if the Fair Market Value ofone share of the Company’s Common Stock subject to this Warrant is greater than the Exercise Price,then in effect as adjusted pursuant to this Warrant, this Warrant shall be deemed automaticallyexercised pursuant to Section 2.2 above, even if not surrendered. For purposes of suchautomatic exercise, the Fair Market Value of the Company’s Common Stock upon such expiration shallbe determined pursuant to Section 2.2 (b) above. To the extent this Warrant or any portionthereof is deemed automatically exercised pursuant to this Section, the Company agrees to promptlynotify the Warrantholder of the number of Warrant Shares, if any, the Warrantholder hereof is toreceive by reason of such automatic exercise.          **2.4****Exercise in Connection with an Initial Public Offering, Sale or Merger****.**Notwithstanding any other provision hereof, if the exercise of all or any portion of this Warrantis made or to be made in connection with the occurrence of a public offering, sale or merger of theCompany, the exercise of all or any portion of this Warrant shall, at the election of theWarrantholder, be conditioned upon the consummation of the public offering, sale or merger of theCompany in which case such exercise shall not be deemed to be effective until the consummation ofsuch transaction. In the event that transaction is not consummated within forty-five (45) days ofthe targeted date of the transaction, any such exercise shall, at the election of theWarrantholder, be deemed rescinded.
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          **2.5****Warrant Shares Certificate****.**A stock certificate for the Warrant Sharesspecified in the Exercise Form shall be delivered to the Warrantholder within five (5) BusinessDays after receipt of the Exercise Form by the Company and payment by the Warrantholder of theaggregate Exercise Price (or net exercise in lieu of payment as permitted in Section 2.2),along with a check from the Company in lieu of any fractional shares which the Warrantholder wouldbe entitled to purchase under this Warrant. If this Warrant was exercised in part, the Companyshall, at the time of delivery of the stock certificate, deliver to the Warrantholder a new Warrantevidencing the right to purchase the remaining Warrant Shares, which new Warrant shall in all otherrespects be identical with this Warrant.          **2.6****Payment of Taxes****.**The Company shall pay all expenses, taxes and othergovernmental charges with respect to the issue or delivery of the Warrant Shares, unless such taxor charge is imposed by law upon the Warrantholder.     **3. ****Restrictions on Transfer; Restrictive Legends****.**          **3.1****Restrictions on Transfer****.**This Warrant and the Warrant Shares issuable uponexercise of all or part of this Warrant are unregistered securities that are subject to therestrictions on transfer imposed by the Securities Act and applicable state securities laws and may not beoffered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Personother than in accordance with the Securities Act and applicable state securities laws. The WarrantShares issuable upon exercise of all or part of this Warrant are also subject to additionalrestrictions on transfer set forth in the Stockholders’ Agreement and may not be offered, sold,transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than inaccordance with the Stockholders’ Agreement.          **3.2****Restrictive Legends****.**Until such time as the restrictions on transfer imposedon this Warrant by the Securities Act and applicable state securities laws shall no longer beeffective, this Warrant, any Warrant issued to the Warrantholder upon the partial exercise of thisWarrant pursuant to Section 2 shall be stamped or otherwise imprinted with a legend insubstantially the form as set forth on the cover of this Warrant. Until such time as therestrictions on transfer imposed on the Warrant Shares by the Securities Act, applicable statesecurities laws and the Stockholders’ Agreement shall no longer be effective, each stockcertificate for Warrant Shares and each stock certificate issued upon the direct or indirecttransfer of any such Warrant Shares shall be stamped or otherwise imprinted with a legend insubstantially the form provided in the Stockholders’ Agreement. Upon the termination of suchrestrictions on transfer, the Warrantholder may require the Company to issue a Warrant or a stockcertificate for Warrant Shares, in each case without a legend, if and to the extent permitted by,and in accordance with, the Stockholders’ Agreement and applicable law.     **4. ****Reservation and Registration of Warrant Shares****.**The Company covenants andagrees as follows:          **4.1****Validly Issued and Free of Encumbrances****.**All Warrant Shares issued upon theexercise of all or any part of this Warrant shall, upon issuance and payment of the Exercise Pricetherefore (or upon net exercise as permitted herein), be validly issued, fully paid
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andnonassessable, issued in compliance with all applicable federal and state securities laws, and freefrom all taxes, liens and charges with respect to the issue thereof, and not subject to anypreemptive rights.          **4.2****Sufficient Authorized Shares****.**During the period within which the rightsrepresented by this Warrant may be exercised, the Company shall at all times have authorized andreserved, for the purpose of issuance of Common Stock upon any exercise of the purchase rightsevidenced by this Warrant, and shall keep available free from preemptive rights, a sufficientnumber of shares of its Common Stock to provide for the exercise of the rights represented by thisWarrant.          **4.3****Noncontravention****.**The Company shall not, by amendment of its Charter orthrough any reorganization, transfer of assets, spin-off, consolidation, merger, dissolution, issueor sale of securities or any other action or inaction, avoid or seek to avoid the observance orperformance of any of the terms of this Warrant to be observed or performed hereunder, and shall atall times in good faith assist in performing, carrying out, and giving effect to the terms hereofand in the taking of all such actions as may be necessary or appropriate in order to protect therights of the Warrantholder against dilution or other impairment.     **5. ****Anti-Dilution Adjustments****.**From and after the date hereof and until theExpiration Date, notwithstanding the fact that no Warrant Shares shall be issued and outstanding,the Exercise Price, and the number and type of Warrant Shares or other securities to be receivedupon exercise of this Warrant, shall be subject to adjustment as follows:          **5.1****Issuances of Common Stock Below Exercise Price****.**          (a) If the Company shall, at any time or from time to time after the Original IssuanceDate, issue any shares of Common Stock (or be deemed to have issued shares of Common Stock asprovided herein), other than Excluded Stock, without consideration or for a consideration per shareless than the Exercise Price in effect immediately prior to the issuance of such Common Stock, thenthe Exercise Price, as in effect immediately prior to each such issuance, shall forthwith belowered to:          (1) on or after the Operational Date, a price equal to the quotient obtained by dividing:          (A) an amount equal to the sum of (X) the total number of shares of Common Stock DeemedOutstanding immediately prior to such issuance, *multiplied by*the Exercise Price in effectimmediately prior to such issuance, and (Y) the consideration received by the Company upon suchissuance; by          (B) the total number of shares of Common Stock Deemed Outstanding immediately after theissuance of such Common Stock; or          (2) until the Operational Date, the lowest price per share at which any such shares ofCommon Stock have been issued or sold or deemed to have been issued or sold.
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          (b) for the purposes of any adjustment of the Exercise Price pursuant to paragraph(a) above, the following provisions shall be applicable:          (1) In the case of the issuance of Common Stock for cash in a public offering or privateplacement, the consideration shall be deemed to be the amount of cash paid therefor after deductingtherefrom any discounts, commissions or placement fees payable by the Company to any underwriter orplacement agent in connection with the issuance and sale thereof.          (2) In the case of the issuance of Common Stock for a consideration in whole or in partother than cash, the consideration other than cash shall be deemed to be the fair value per sharethereof, as reasonably determined in good faith by the Board, irrespective of any accountingtreatment.          (3) In the case of the issuance of options to purchase or rights to subscribe for CommonStock, securities by their terms convertible into or exchangeable for Common Stock, or options topurchase or rights to subscribe for such convertible or exchangeable securities (except for optionsor rights to acquire or subscribe for Excluded Stock):          (A) the aggregate maximum number of shares of Common Stock deliverable upon exercise ofsuch options to purchase or rights to subscribe for Common Stock shall be deemed to have beenissued at the time such options or rights were issued and for a consideration equal to theconsideration (determined in the manner provided in Sections5.1(b)(1) and5.1(b)(2) above), if any, received by the Company upon the issuance of such options orrights plus the minimum purchase price provided in such options or rights for the Common Stockcovered thereby;          (B) the aggregate maximum number of shares of Common Stock deliverable upon conversion ofor in exchange for any such convertible or exchangeable securities or upon the exercise of optionsto purchase or rights to subscribe for such convertible or exchangeable securities and subsequentconversion or exchange thereof shall be deemed to have been issued at the time such securities,options or rights were issued and for a consideration equal to the consideration received by theCompany for any such securities and related options or rights (excluding any cash received onaccount of accrued interest or accrued dividends), plus the additional consideration, if any, to bereceived by the Company upon the conversion or exchange of such securities or the exercise of anyrelated options or rights (the consideration in each case to be determined in the mannerprovided in Sections 5.1(b)(1) and 5.1(b)(2) above);          (C) on any change in the number of shares or exercise price of Common Stock deliverableupon exercise of any such options or rights or conversions of or exchanges for such securities,other than a change resulting from the antidilution provisions thereof, the Exercise Price shallforthwith be readjusted to the Exercise Price as would have been obtained had the adjustment madeupon the issuance of such options, rights or securities not converted prior to such change oroptions or rights related to such securities not converted prior to such change been made upon thebasis of such change; and
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          (D) on the expiration of any such options or rights, the termination of any such rights toconvert or exchange or the expiration of any options or rights related to such convertible orexchangeable securities, the Exercise Price shall forthwith be readjusted to the Exercise Price aswould have been obtained had the adjustment made upon the issuance of such options, rights,securities or options or rights related to such securities been made upon the basis of the issuanceof only the number of shares of Common Stock actually issued upon the exercise of such options orrights, upon the conversion or exchange of such securities, or upon the exercise of the options orrights related to such securities and subsequent conversion or exchange thereof.          (c) Whenever the Exercise Price is adjusted under this Section 5.1, the number ofWarrant Shares issuable on exercise hereof shall be multiplied by a fraction the numerator of whichis the Exercise Price immediately before such adjustment and the denominator is the Exercise Priceas so adjusted.          **5.2****Stock Dividends and Combinations****.**          (a) If, at any time after the Original Issuance Date, the number of shares of Common Stockoutstanding is increased by a stock dividend payable in shares of Common Stock or by a subdivisionor split-up of shares of Common Stock, then, following the record date for the determination ofholders of Common Stock entitled to receive such stock dividend, subdivision or split-up, theExercise Price shall be decreased and the number of shares of Common Stock issuable on exercise ofthis Warrant shall be increased in proportion to such increase in outstanding shares.          (b) If, at any time after the Original Issuance Date, the number of shares of Common Stockoutstanding is decreased by a combination of the outstanding shares of Common Stock, then,following the record date for such combination, the Exercise Price shall be increased and thenumber of shares of Common Stock issuable on exercise of this Warrant shall be decreased inproportion to such decrease in outstanding shares.          **5.3****Recapitalization, Etc****.**In the event of any capital reorganization of theCompany, any reclassification of the stock of the Company (other than a change in par value or frompar value to no par value or from no par value to par value or as a result of a stock dividend orsubdivision, split-up or combination of shares), or any consolidation or merger of the Company,this Warrant shall after such reorganization, reclassification, consolidation or merger beexercisable for the kind and number of shares of stock or other securities or property of theCompany or of the company resulting from such consolidation or surviving such merger to which theholder of the number of shares of Common Stock deliverable (immediately prior to the time of suchreorganization, reclassification, consolidation or merger) upon exercise of this Warrant would havebeen entitled upon such reorganization, reclassification, consolidation or merger. The provisionsof this clause shall similarly apply to successive reorganizations, reclassifications,consolidations and mergers.          **5.4****De Minimis Adjustments****.**No adjustment in the Exercise Price shall be requiredunless such adjustment would require an increase or decrease of at least 0.1% in the ExercisePrice; *provided*, *however*that any adjustments not required to be made by virtue of this sentenceshall be carried forward and taken into account in any subsequent adjustment. All
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calculationsunder this Section 5 shall be made to the nearest one hundredth (1/100) of a cent or thenearest one tenth (1/10) of a share, as the case may be.          **5.5****Statement of Adjustments****.**Whenever the Exercise Price shall be adjusted asprovided in this Section 5, the Company shall make available for inspection during regularbusiness hours, at its principal executive offices or at such other place as may be designated bythe Company, a statement, signed by its chief executive officer, showing in detail the factsrequiring such adjustment and the Exercise Price that shall be in effect after such adjustment.The Company shall also cause a copy of such statement to be sent by first class certified mail,return receipt requested and postage prepaid, to the Warrantholder at such Warrantholder’s addressappearing on the Company’s records. Where appropriate, such copy may be given in advance and maybe included as part of any notice required to be mailed under the provisions of Section 5.6below.          **5.6****Notices****.**If the Company shall propose to take any action of the typesdescribed in Sections 5.2, 5.3, or 5.7 the Company shall give notice toeach Warrantholder, which notice shall specify the record date, if any, with respect to any suchaction and the date on which such action is to take place. Such notice shall also set forth suchfacts with respect thereto as shall be reasonably necessary to indicate the effect of such action(to the extent such effect may be known at the date of such notice) on the Exercise Price and thenumber, kind or class of shares or other securities or property which shall be deliverable orpurchasable upon the occurrence of such action or deliverable upon exercise of this Warrant. Inthe case of any action which would require the fixing of a record date, such notice shall be givenat least twenty (20) days prior to the date so fixed, and in case of all other action, such noticeshall be given at least thirty (30) days prior to the taking of such proposed action. Failure togive such notice, or any defect therein, shall not affect the legality or validity of any suchaction.          **5.7****Dividends****.**Without duplication of any other adjustment provided for in thisSection 5, at any time the Company makes or fixes a record date for the determination ofholders of Common Stock entitled to receive a dividend or other distribution payable in property orsecurities of the Company other than shares of Common Stock, then, and in each such case,          (a) the Exercise Price then in effect shall be adjusted (and any other appropriate actionshall be taken by the Company) by multiplying the Exercise Price in effect immediately prior to thedate of such dividend or distribution by a fraction, (i) the numerator of which shall be the FairMarket Value (in all such cases under Section 5.7, as shall be determined pursuant toSection 2.2) of Common Stock immediately prior to the date of such dividend ordistribution, less the Fair Market Value of the portion of the property or securities applicable toone share of Common Stock so dividended or distributed, and (ii) the denominator of which shall bethe Fair Market Value of the Common Stock immediately prior to the date of such dividend ordistribution (such fraction not to be greater than one); and          (b) the number of Warrant Shares for which this Warrant is exercisable immediately priorto such dividend or distribution shall be adjusted (and any other appropriate actions shall betaken by the Company) by multiplying the then-current number of Warrant Shares in effectimmediately prior to the date of such dividend or distribution by a fraction, (i) the numerator ofwhich shall be the Exercise Price in effect immediately prior to the date of such
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dividend or distribution, and (ii) thedenominator of which shall be the adjusted Exercise Price as determined pursuant toSection 5.7(a) above (such fraction not to be less than one).          Such adjustments shall be made whenever the Company makes or fixes a record date for thedetermination of holders of Common Stock entitled to receive a dividend or other distributionpayable in property or securities of the Company (other than shares of Common Stock) and shallbecome effective retroactively to a date immediately following the close of business on the recorddate for the determination of stockholders entitled to receive such dividend or distribution.          **5.8****Waiver****.**In the event that holders of at least sixty-six and two thirdspercent (662⁄3%) of the Warrants, as the case may be, consent in writing to limit, or waive in itsentirety, any antidilution adjustment to which the Warrantholders would otherwise be entitledhereunder, the Company shall not be required to make any adjustment whatsoever in excess of suchlimit or at all, as the terms of such consent may dictate.          **5.9****Computations****.**The computations of all amounts under this Section 5shall be made assuming all other antidilution or similar adjustments to be made to the terms of allother securities resulting from the transaction causing an adjustment pursuant to this Section5 have previously been made so as to maintain the relative economic interest of the Warrantsvisàvis all other securities issued by the Company..          **5.10****Par Value****.**The Company shall take or cause to be taken such steps as shallbe necessary to ensure that the par value per share of Common Stock is at all times less than orequal to the Exercise Price.     **6. ****Transfer and Exchange****.**If this Warrant is presented to the Company with arequest to register a transfer or to exchange it for an equal number of Warrants of otherdenominations the Company will do so.     **7. ****Loss or Destruction of Warrant****.**Subject to the terms and conditions hereof,upon receipt by the Company of evidence reasonably satisfactory to it of the loss, theft,destruction or mutilation of this Warrant and, in the case of loss, theft or destruction, of suchbond or indemnification as the Company may reasonably require, and, in the case of such mutilation,upon surrender and cancellation of this Warrant, the Company will execute and deliver to theWarrantholder a new Warrant of like tenor.     **8. ****Ownership of Warrant****.**The Company may deem and treat the Person in whose namethis Warrant is registered as the Warrantholder and owner hereof (notwithstanding any notations ofownership or writing hereon made by anyone other than the Company) for all purposes and shall notbe affected by any notice to the contrary, until presentation of this Warrant for registration oftransfer.     **9. ****Amendments****.**Any provision of this Warrant may be amended and the observancethereof waived only with the written consent of the Company and the Warrantholder.     **10. ****Definitions****.**As used herein, unless the context otherwise requires, thefollowing terms have the following respective meanings:
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          “**Affiliate**” means, (1) with respect to any Person, any of (a) a director,officer or stockholder holding 5% or more of the capital stock (on a fully diluted basis) of suchPerson, (b) a spouse, parent, sibling or descendant of such Person (or a spouse, parent, sibling ordescendant of any director or officer of such Person) and (c) any other Person that, directly orindirectly through one or more intermediaries, controls, or is controlled by, or is under commoncontrol with, another Person or (2) in any event, any Person meeting the definition of “Affiliate”set forth in Rule 405 under the Securities Act. The term “control” includes, without limitation,the possession, directly or indirectly, of the power to direct the management and policies of aPerson, whether through the ownership of voting securities, by contract or otherwise.          “**Board of Directors**” or “**Board**” means the Board of Directors of the Company.          “**Business Day**” means any day other than a Saturday, Sunday or a day on which nationalbanks are authorized by law to close in the Commonwealth of Massachusetts.          “**Charter**” means the Amended and Restated Certificate of Incorporation of the Company,as amended from time to time.          “**Common Stock**” means the Company’s presently authorized Common Stock, and any stockinto or for which such Common Stock may hereafter be converted or exchanged pursuant to the Charterof the Company as amended from time to time as provided by law and in such Charter.          “**Common Stock Deemed Outstanding**” means, at any given time, the sum of (i) the numberof shares of Common Stock actually outstanding at such time, (ii) the number of shares of CommonStock issuable upon conversion of the Preferred Stock, and (iii) the number of shares of CommonStock issuable upon the exercise in full of all Convertible Securities whether or not theConvertible Securities are convertible into Common Stock at such time, but shall exclude any sharesof Common Stock or Convertible Securities in the treasury of the Company or held for the account ofthe Company or any of its subsidiaries.          “**Convertible Securities**” means securities or obligations that are exercisable for,convertible into or exchangeable for shares of Common Stock. The term includes options, warrantsor other rights to subscribe for or purchase Common Stock or to subscribe for or purchase othersecurities that are convertible into, directly or indirectly, or exchangeable for Common Stock.          “**Excluded Stock**” has the meaning set forth in the Stockholders Agreement.          “**Operational Date**” means the first date on which the Company’s operations for theproduction of the aerogel product meets each of the following criteria: (i) Quality — aerogelproducts meet the pre-established product specifications and are moved to inventory for sale; (ii)Quantity — one million square feet of aerogel product produced per calendar month for twoconsecutive months (based upon a 20 extractor plant and adjusted accordingly for any increase inplant capacity); and (iii) Variable costs — less than $.84 per square foot cast.          “**Original Issuance Date**” means the date and time that the first Warrant is issued bythe Company.
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          “**Person**” means any individual, firm, corporation, partnership, limited liabilitycompany, trust, incorporated or unincorporated association, joint venture, joint stock company,governmental authority or other entity of any kind, and shall include any successor (by merger orotherwise) of such entity.          “**Preferred Stock**” has the meaning set forth in the Charter.          “**Purchase Agreement**” means the Stock Purchase Agreement under which the Series DConvertible Preferred Stock were issued.          “**QPO**” means an underwritten public offering (underwritten by a reputable underwriterof national reputation) of shares of Common Stock registered pursuant to the Securities Actinvolving aggregate proceeds to the Company of at least $50,000,000 with an offering price pershare of at least $6.36.          “**Registration Rights Agreement**” means the Third Amended and Restated RegistrationRights Agreement, dated as of June 10, 2008, as amended, among the Company and certain partiesthereto, as the same may be amended, modified or supplemented from time to time.          “**Securities Act**” means the Securities Act of 1933, as amended, and the rules andregulations of the United States Securities and Exchange Commission thereunder.          “**Stockholders’ Agreement**” means the Third Amended and Restated Stockholders’Agreement, dated as of June 10, 2008, by and among the Company and each other stockholder of theCompany party thereto, as amended from time to time.     **11.****Miscellaneous Provisions****.**          **11.1****Entire Agreement****.**This Warrant, the Financing Arrangement, the Stockholders’Agreement, the Registration Rights Agreement and the Purchase Agreement constitute the entireagreement between the Company and the Warrantholder with respect to this Warrant.          **11.2****Binding Effect; Benefits****.**This Warrant shall inure to the benefit of and shallbe binding upon the Company and the Warrantholder and their respective permitted successors andassigns. Nothing in this Warrant, expressed or implied, is intended to or shall confer on anyperson other than the Company and the Warrantholder, or their respective permitted successors orassigns, any rights, remedies, obligations or liabilities under or by reason of this Warrant.          **11.3****Section and Other Headings****.**The section and other headings contained in thisWarrant are for reference purposes only and shall not be deemed to be a part of this Warrant or toaffect the meaning or interpretation of this Warrant.
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          **11.4****Notices****.**All notices, demands and other communications provided for or permittedhereunder shall be made in writing and shall be by registered or certified first-class mail, returnreceipt requested, telecopier, courier service, overnight mail or personal delivery:If to the Company:Aspen Aerogels, Inc.