WARRANT

Exhibit 4.3 WARRANT THE SECURITIES REPRESENTED BY THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS. THE SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND MAY NOT BE OFFERED, SOLD, TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR AN OPINION OF COUNSEL, REASONABLY SATISFACTORY TO THE COMPANY, THAT REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT OR APPLICABLE STATE SECURITIES LAWS UNLESS SOLD PURSUANT TO RULE 144 UNDER THE SECURITIES ACT. LIGHTING SCIENCE GROUP CORPORATION Warrant To Purchase Common Stock

THIS CERTIFIES THAT, for value received, Haynes and Boone, LLP or its transferees, successors, affiliates and assigns (the " Holder ") is entitled to purchase from Lighting Science Group Corporation, a Delaware corporation (the " Company "), at any time after a Liquidation Event (defined below) has occurred (subject to Section 2(a)) and before the Expiration Date (defined below) at $0.85 per share (the " Exercise Price ") four hundred eighty two thousand three hundred fifty three (482,353) fully paid nonassessable shares of Common Stock (defined below) (the " Warrant Shares "), all subject to adjustment and upon the terms and conditions provided herein.      Section 1. Definitions .           The following terms as used in this Warrant have the following meanings:           (a) " Business Day " means any day other than Saturday, Sunday or federal holiday.           (b) " Change of Control " means the existence or occurrence of any of the following: (a) the sale, conveyance, contribution or disposition of all or substantially all of the assets of the Corporation (including pursuant to a joint venture arrangement or other transaction in which the Corporation receives more than fifty percent (50%) of the voting equity in another entity or a general partnership); (b) the effectuation of a transaction or series of related transactions in which more than fifty percent (50%) of the voting power of the Corporation is disposed of (other than as a direct result of normal, uncoordinated trading activities in the Common Stock generally); (c) the consolidation, merger or other business combination of the Corporation with or into any

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other entity, immediately following which the prior stockholders of the Corporation fail to own, directly or indirectly, at least fifty percent (50%) of the voting equity of the surviving entity; (d) a transaction or series of transactions in which any Person or "group" (as such term is used in Sections 13(d) and 14(d) of the Exchange Act) acquires more than fifty percent (50%) of the voting equity of the Corporation; (e) the replacement of a majority of the Board of Directors with individuals who were not nominated or elected by at least a majority of the directors at the time of such replacement; or (f) a transaction or series of transactions that constitutes or results in a "going private transaction" (as defined in Section 13(e) of the Exchange Act and the regulations of the Commission issued thereunder).           (c) " Common Stock " means (i) the Company’s common stock, $.001 par value per share, and (ii) any capital stock into which the Common Stock is changed or any capital stock resulting from a reclassification of the Common Stock.           (d) " Exchange Act " means the Securities Exchange Act of 1934, as amended.           (e) " Exercise Price " is equal to $0.85, subject to adjustment as set forth in this Warrant.           (f) " Expiration Date " means the fifth anniversary of the Issuance Date or, if such date falls on a day that is not a Business Day or a day on which trading does not take place on the principal exchange or automated quotation system on which the Common Stock is traded, the next Business Day.           (g) " Issuance Date " means December 31, 2008.           (h) " Liquidation Event " means any voluntary or involuntary liquidation, dissolution or winding-up of the Corporation, a Change of Control of the Corporation or the redemption, repurchase or other acquisition of all of the shares of the Corporation’s Series C Preferred Stock, par value $0.001 per share, outstanding on the date hereof by the Corporation.           (i) " Person " means a natural person or entity, or a government or any division, department or agency thereof.           (j) " Securities Act " means the Securities Act of 1933, as amended.           (k) " Warrant " means this Warrant and all Warrants issued in exchange, transfer or replacement thereof.           (l) "Warrant Shares" has the meaning attributed to it in the preamble of this Warrant.      Section 2. Exercise of Warrant .           (a) This Warrant may be exercised by the Holder registered on the books of the Company, in whole or in part, at any time (i) on any Business Day after the occurrence of a Liquidation Event, but in no event before 75 days after the Issuance Date (for the avoidance of doubt, this Warrant shall become immediately exercisable on such 75th day in the event that a

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Liquidation Event occurs any time after the Issuance Date but before such 75th day) and (ii) prior to 11:59 p.m. Eastern Time on the Expiration Date. Any exercise of this Warrant shall be effected by: (1) delivery of a written notice, in the form attached as Exhibit A (the " Exercise Notice "), of Holder’s election to exercise this Warrant, specifying the number of Warrant Shares to be purchased, (2) payment to the Company of an amount equal to the Exercise Price multiplied by the number of Warrant Shares being purchased (a) in cash or wire transfer of immediately available funds; (b) by means of a cashless exercise pursuant to Section 2(c); or (c) by surrender of shares of the Company’s preferred stock pursuant to Section 2(d) (such cash, wire transfer, cashless exercise or surrender referred to herein as the " Payment ") and (3) the surrender at the principal office of the Company or to a nationally recognized courier for overnight delivery to the Company, as soon as practicable following such date, of this Warrant, (or an indemnification undertaking with respect to this Warrant in the case of its loss, theft or destruction in such form and substance as reasonably satisfactory to the Company).      The Company shall, not later than the fifth Business Day (the " Delivery Date ") following receipt of an Exercise Notice, the Payment and this Warrant or such indemnification (collectively, the " Exercise Documents "), arrange for its transfer agent, on or before the Delivery Date, to issue and surrender to a nationally recognized courier for overnight delivery to the address specified in the Exercise Notice, a certificate, registered in the name of the Holder, for the number of shares of Common Stock to which the Holder is entitled. Upon delivery of the Exercise Notice and the Payment, the Holder shall be deemed for all corporate purposes to have become the holder of record of the Warrant Shares with respect to which this Warrant has been exercised on the Delivery Date, irrespective of the date of delivery of the certificates evidencing the Warrant Shares.           (b) Unless the rights represented by this Warrant have expired or been fully exercised, the Company shall, as soon as practicable and in no event later than five Business Days after receipt of the Exercise Documents and at its own expense, issue a new Warrant identical in all respects to this Warrant, except it shall represent rights to purchase the number of Warrant Shares purchasable immediately prior to exercise, less the number purchased.           (c) In lieu of exercising this Warrant by means of paying via cash or wire transfer, the Holder may elect to make the Payment by means of receiving shares equal to the value of this Warrant (or portion thereof being exercised) by delivery and surrender of this Warrant together with the Exercise Notice in accordance with the terms hereof, duly completed to indicate a net issuance exercise and executed by the Holder, in which event the Company shall issue to the Holder a number of shares of Common Stock of the Company computed using the following formula:      X = Y(A-B)/A      where X = the number of shares issued to the Holder;

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          (d) In lieu of or in addition to exercising this Warrant by means of paying via cash or wire transfer, the Holder may elect to make the Payment by surrender of shares of preferred stock owned by the Holder. In such case, the Holder shall surrender the number of shares of preferred stock, properly endorsed to the Company, having an aggregate liquidation value at the date of the calculation (as provided in the applicable certificate of designation) equal to the Exercise Price at the date of the calculation multiplied by the number of Warrant Shares being purchased. Unless all of the shares represented by the certificate for preferred shares have been surrendered, the Company shall, as soon as practicable and in no event later than five Business Days after receipt of the Exercise Documents and at its own expense, issue a new certificate representing the remaining preferred shares owned by the Holder.           (e) No fractional shares of Common Stock are to be issued upon the exercise of this Warrant, but rather the number of shares of Common Stock issued shall be rounded up or down to the nearest whole number.      Section 3. Covenants as to Common Stock . The Company hereby covenants and agrees as follows:           (a) This Warrant is, and any Warrants issued in substitution for or in replacement of this Warrant upon issuance will be, duly authorized, executed and delivered.           (b) All Warrant Shares upon issuance will be validly issued, fully paid and nonassessable and free from all liens and charges with respect to the issue thereof.           (c) As long as this Warrant may be exercised, the Company will have authorized and reserved at least the number of shares of Common Stock needed to provide for the exercise of the rights then represented by this Warrant.      Section 4. Warrant Holder Not Deemed a Shareholder . Except as specifically provided in Section 2(a), nothing contained in this Warrant shall be construed to (a) grant the Holder any rights to vote or receive dividends or be deemed the holder of shares of the Company for any purpose, (b) confer upon the Holder any of the rights of a shareholder of the Company or any right to vote, give or withhold consent to any corporate action (whether any reorganization, issue of stock, reclassification of stock, consolidation, merger, conveyance or otherwise), receive notice of meetings, receive dividends or subscription rights, or otherwise, or (c) impose any liabilities on the Holder to purchase any securities or as a shareholder of the Company, whether asserted by the Company or creditors of the Company, prior to the issuance of the Warrant Shares.      Section 5. Representations of Holder . The Holder, by the acceptance hereof, represents that it is acquiring this Warrant and the Warrant Shares for its own account for investment only and not with a view towards, or for resale in connection with, the public sale or distribution of this Warrant or the Warrant Shares, except pursuant to sales registered or exempted under the Securities Act. The Holder further represents, by acceptance hereof, that, as of this date, Holder is an "accredited investor" as defined in Rule 501(a)(1) of Regulation D

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promulgated under the Securities Act (an "Accredited Investor" ). Upon exercise of this Warrant, the Holder shall, if requested by the Company, confirm in writing, in a form satisfactory to the Company, that the Warrant Shares are being acquired solely for the Holder’s own account and not as a nominee for any other party, for investment, and not with a view toward distribution or resale and that Holder is an Accredited Investor. If Holder cannot make such representations because they would be factually incorrect, it shall be a condition to Holder’s exercise of this Warrant that the Company receive such other representations as the Company considers reasonably necessary to assure the Company that the issuance of its securities upon exercise of this Warrant shall not violate any federal or state securities laws. The Company shall not be penalized or disadvantaged by a Holder’s inability to exercise this Warrant due to its inability to make the required representations in connection with the exercise of this Warrant.      Section 6. Ownership and Transfer .           (a) The Company shall maintain at its principal executive offices (or such other office or agency of the Company as it may designate by notice to the holder hereof), a register for this Warrant, in which the Company shall record the name and address of the Person in whose name this Warrant has been issued, as well as the name and address of each transferee who has acquired this Warrant in accordance with applicable law and the terms of this Warrant. The Company may treat the Person in whose name this Warrant is registered on the register as the owner and holder thereof for all purposes, notwithstanding any notice to the contrary, but in all events recognizing any transfers made in accordance with the terms of this Warrant.           (b) This Warrant may only be offered, sold, transferred or assigned in compliance with the Securities Act and applicable state securities laws.           (c) Subject to the terms of this Section 6, upon surrender of this Warrant to the Company at its principal office or at the office of its transfer agent, if any, with the Assignment Form annexed hereto as Exhibit B duly executed and funds sufficient to pay any transfer tax, the Company shall, without charge, execute and deliver a new Warrant in the name of the assignee evidencing the portion of the Warrant certificate so transferred and a new Warrant certificate evidencing the remaining portion of the Warrant certificate not so transferred, if any, shall be issued to the transferring Holder. The delivery of the new Warrant certificate by the Company to the transferee thereof shall be deemed to constitute acceptance by such transferee of all of the rights and obligations of a holder of a Warrant certificate. Subject to the terms of this Section 6, this Warrant may be divided or combined with other warrants which carry the same rights upon presentation hereof at the principal office of the Company together with a written notice specifying the names and denominations in which new Warrants are to be issued and signed by the Warrant Holder hereof.      Section 7. Adjustment of Exercise Price and Number of Shares . The Exercise Price and the number of Warrant Shares shall be adjusted from time to time as follows:           (a) Stock Splits . If the Company subdivides (by any stock split, recapitalization or otherwise) its outstanding shares of Common Stock into a greater number of shares, the Exercise Price in effect immediately prior to the subdivision will be proportionately reduced and the number of Warrant Shares will be proportionately increased. If th