Exhibit 4.3

THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE “ACT”), AS AMENDED, OR ANY APPLICABLE STATE SECURITIES LAWS, AND MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SUCH ACT AND ANY APPLICABLE STATE SECURITIES LAWS.

WARRANT TO PURCHASE COMMON STOCK

of

SOLAZYME, INC.

Void after [    ]

This certifies that, for value received, [    ] or its assigns (“Holder”) is entitled, subject to the terms set forth below, to purchase from Solazyme, Inc. (the “Company”), a Delaware corporation, up to [    ] shares of the Common Stock of the Company, as constituted on the date hereof (the “Warrant Issue Date”), upon surrender hereof, at the principal office of the Company referred to below, and simultaneous payment therefor in lawful money of the United States or otherwise as hereinafter provided, of the Exercise Price as set forth in Section 2 below. The number, character and Exercise Price of such shares of Common Stock are subject to adjustment as provided below. The term “Warrant” as used herein shall include this Warrant, and any warrants delivered in substitution or exchange therefor as provided herein.

1. Term of Warrant. Subject to the terms and conditions set forth herein, this Warrant shall be exercisable, in whole or in part, at any time, or from time to time, commencing on [    ] and ending at the earliest of (a) 5:00 p.m. Pacific time on [    ], or (b) immediately prior to the closing of a firm commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended (the “Act”), covering the offer and sale of equity securities of the Company to the public (the “IPO”). The first to occur among clauses (a) or (b) in the preceding sentence shall be the expiration date (the “Expiration Date”) of this Warrant and the right of a Holder to exercise this Warrant shall be terminated on such Expiration Date. The Company will give the Holder notice specifying the date of an IPO by overnight delivery at least five (5) days prior to the date of the scheduled occurrence thereof.

2. Exercise Price. The Exercise Price at which this Warrant may be exercised shall be [    ] per share of Common Stock, as adjusted from time to time pursuant to Section 12 hereof.

3. Exercise of Warrant.

(a) The purchase rights represented by this Warrant are exercisable by the Holder in whole or in part, at any time, or from time to time, during the term hereof as described in Section 1 above, by the surrender of this Warrant and the Notice of Exercise annexed hereto duly completed and executed on behalf of the Holder, at the principal office of the Company (or such other office or agency of the Company as it may designate by notice in writing to the Holder at the address of the Holder appearing on the books of the Company), upon payment (i) in cash or by check acceptable to the Company, (ii) by cancellation by the Holder of indebtedness or other obligations of the Company to the Holder, or (iii) by a combination of (i) and (ii), of the purchase price of the shares to be purchased.

(b) This Warrant shall be deemed to have been exercised immediately prior to the close of business on the date of its surrender for exercise as provided above, and the person or persons entitled to receive the shares of Common Stock issuable upon such exercise shall be treated for all purposes as the holder of record of such shares as of the close of business on such date. As promptly as practicable on or after such date and in any event within forty-five (45) days thereafter, the Company, at its expense, shall issue and deliver to the person or persons entitled to receive the same a certificate or certificates for the number of shares issuable upon such exercise. In the event that this Warrant is exercised in part, the Company at its expense, will execute and deliver a new Warrant of like tenor exercisable for the number of shares for which this Warrant may then be exercised.

4. No Fractional Shares or Scrip. No fractional shares or scrip representing fractional shares shall be issued upon the exercise of this Warrant and the number of shares of Common Stock shall be rounded down to the nearest whole share. In lieu of any fractional share to which the Holder would otherwise be entitled, the Company shall make a cash payment equal to the Exercise Price multiplied by such fraction.

5. Replacement of Warrant. On receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant and, in the case of loss, theft or destruction, on delivery of an indemnity agreement reasonably satisfactory in form and substance to the Company or, in the case of mutilation, on surrender and cancellation of this Warrant, the Company at its expense shall execute and deliver, in lieu of this Warrant, a new warrant of like tenor and amount.

6. Rights of Stockholders. The Holder shall not be entitled to vote or receive dividends or be deemed the holder of Common Stock or any other securities of the Company that may at any time be issuable on the exercise hereof for any purpose, nor shall anything contained herein be construed to confer upon the Holder, as such, any of the rights of a stockholder of the Company or any right to vote for the election of

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directors or upon any matter submitted to stockholders at any meeting thereof, or to give or withhold consent to any corporate action (whether upon any recapitalization, issuance of stock, reclassification of stock, change of par value, or change of stock to no par value, consolidation, merger, conveyance, or otherwise) or to receive notice of meetings, or to receive dividends or subscription rights or otherwise until the Warrant shall have been exercised as provided herein.

7. Transfer of Warrant.

(a) Warrant Register. The Company will maintain a register (the “Warrant Register”) containing the names and addresses of the Holder or Holders. Any Holder of this Warrant or any portion thereof may change his or her address as shown on the Warrant Register by written notice to the Company requesting such change. Any notice or written communication required or permitted to be given to the Holder may be delivered or given by mail to such Holder as shown on the Warrant Register and at the address shown on the Warrant Register. Until this Warrant is transferred on the Warrant Register of the Company, the Company may treat the Holder as shown on the Warrant Register as the absolute owner of this Warrant for all purposes, notwithstanding any notice to the contrary.

(b) Warrant Agent. The Company may, by written notice to the Holder, appoint an agent for the purpose of maintaining the Warrant Register referred to in Section 7(a) above, issuing the Common Stock or other securities then issuable upon the exercise of this Warrant, exchanging this Warrant, replacing this Warrant, or any or all of the foregoing. Thereafter, any such registration, issuance, exchange, or replacement, as the case may be, shall be made at the office of such agent.

(c) Transferability and Non-negotiability of Warrant. This Warrant or the Shares of Common Stock issued upon exercise hereof may not be transferred or assigned in whole or in part without prior compliance with all applicable federal and state securities laws by the transferor and the transferee (including the delivery of investment representation and/or opinion letters reasonably satisfactory to the Company, if such are requested by the Company). Subject to the provisions of this Warrant with respect to compliance with the Securities Act of 1933, as amended (the “Act”), and upon notice to the Company of the portion of this Warrant being transferred setting forth the name, address and taxpayer identification number of the transferee, title to this Warrant may be transferred by endorsement (by the Holder executing the Assignment Form annexed hereto) and delivery in the same manner as a negotiable instrument transferable by endorsement and delivery. Notwithstanding the foregoing, under no circumstances shall the Holder transfer all or any part of this Warrant or the Common Stock issuable upon exercise of this Warrant to any direct or indirect competitor of the Company. The terms and conditions of this Warrant shall inure to the benefit of, and be binding upon, the Company and the holders hereof and their respective permitted successors and assigns.

(d) Exchange of Warrant upon a Transfer. On surrender of this Warrant for exchange, properly endorsed on the Assignment Form and subject to the provisions of this Warrant with respect to compliance with the Act and with the limitations on

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assignments and transfers contained in this Section 7, the Company at its expense shall issue to or on the order of the Holder a new warrant or warrants of like tenor, in the name of the Holder or as the Holder (on payment by the Holder of any applicable transfer taxes) may direct, for the number of shares issuable upon exercise hereof.

(e) Compliance with Securities Laws.

(i) The Holder of this Warrant, by acceptance hereof, acknowledges that this Warrant and the shares of Common Stock to be issued upon exercise hereof are being acquired solely for the Holder’s own account and not as a nominee for any other party, and for investment, and that the Holder will not offer, sell or otherwise dispose of this Warrant or any shares of Common Stock to be issued upon exercise hereof except under circumstances that will not result in a violation of the Act or any state securities laws. 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 shares of Common Stock so purchased 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 in violation of the Act.

(ii) This Warrant and all shares of Common Stock issued upon exercise hereof shall be stamped or imprinted with a legend in substantially the following form (in addition to any legend required by state securities laws):

THE SECURITIES REPRESENTED HEREBY HAVE BEEN ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES LAWS. SUCH SECURITIES AND ANY SECURITIES ISSUED HEREUNDER OR THEREUNDER MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SAID ACT AND ANY APPLICABLE STATE SECURITIES LAWS.

8. [Reserved]

9. Authorization of Stock. The Company covenants that during the term this Warrant is exercisable, the Company will have authorized and unissued Common Stock of a sufficient number to provide for the issuance of Common Stock upon the exercise of this Warrant and, from time to time, will take all steps necessary to amend its Certificate of Incorporation (the “Certificate”) to provide sufficient reserves of shares of Common Stock issuable upon exercise of the Warrant. The Company agrees that its issuance of this Warrant shall constitute full authority to its officers who are charged with the duty of executing stock certificates to execute and issue the necessary certificates for shares of Common Stock upon the exercise of this Warrant.

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10. Notices.

(a) Whenever the Exercise Price or number of shares purchasable hereunder shall be adjusted pursuant to Section 12 hereof, the Company shall issue a certificate signed by its Chief Financial Officer setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such adjustment was calculated, and the Exercise Price and number of shares purchasable hereunder after giving effect to such adjustment, and shall cause a copy of such certificate to be mailed (by first-class mail, postage prepaid) to the Holder of this Warrant.

(b) in case:

(i) The Company shall take a record of the holders of its Common Stock (or other stock or securities at the time receivable upon the exercise of this Warrant) for the purpose of entitling them to receive any dividend or other distribution, or any right to subscribe for or purchase any shares of stock of any class or any other securities, or to receive any other right, or

(ii) of any capital reorganization of the Company, any reclassification of the capital stock of the Company, any consolidation or merger of the Company with or into another corporation, or any conveyance of all or substantially all of the assets of the Company to another corporation, or

(iii) of any voluntary dissolution, liquidation or winding-up of the Company,

then, and in each such case, the Company will mail or cause to be mailed to the Holder or Holders a notice specifying, as the case may be, (A) the date on which a record is to be taken for the purpose of such dividend, distribution or right, and stating the amount and character of such dividend, distribution or right, or (B) the date on which such reorganization, reclassification, consolidation, merger, conveyance, dissolution, liquidation or winding-up is to take place, and the time, if any is to be fixed, as of which the holders of record of Common Stock (or such stock or securities at the time receivable upon the exercise of this Warrant) shall be entitled to exchange their shares of Common Stock (or such other stock or securities) for securities or other property deliverable upon such reorganization, reclassification, consolidation, merger, conveyance, dissolution, liquidation or winding-up. Such notice shall be mailed by overnight delivery at least ten (10) days prior to the date therein specified.

(c) All such notices, advices and communications shall be deemed to have been received (i) in the case of personal delivery, on the date of such delivery and (ii) in the case of mailing, on the next business day following the date of such mailing by overnight delivery.

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11. Amendments.

(a) Any term of this Warrant may be amended with the written consent of the Company and the Holder.

(b) No waivers of, or exceptions to, any term, condition or provision of this Warrant, in any one or more instances, shall be deemed to be, or construed as, a further or continuing waiver of any such term, condition or provision.

12. Adjustments. The Exercise Price and the number of shares purchasable hereunder are subject to adjustment from time to time as follows:

12.1 [Reserved].

12.2 Reclassification, etc. If the Company, at any time while this Warrant, or any portion hereof, remains outstanding and unexpired by reclassification of securities or otherwise, shall change any of the securities as to which purchase rights under this Warrant exist into the same or a different number of securities of any other class or classes, this Warrant shall thereafter represent the right to acquire such number and kind of securities as would have been issuable as the result of such change with respect to the securities that were subject to the purchase rights under this Warrant immediately prior to such reclassification or other change and the Exercise Price therefor shall be appropriately adjusted, all subject to further adjustment as provided in this Section 12.

12.3 Split, Subdivision or Combination of Shares. If the Company at any time while this Warrant, or any portion hereof, remains outstanding and unexpired shall split, subdivide or combine the securities as to which purchase rights under this Warrant exist, into a different number of securities of the same class, the number of Shares into which this Warrant is exercisable shall be appropriately adjusted and the Exercise Price for such securities shall be proportionately decreased in the case of a split or subdivision or proportionately increased in the case of a combination.

12.4 Adjustments for Dividends in Stock or Other Securities or Property. If while this Warrant, or any portion hereof, remains outstanding and unexpired, the holders of the securities as to which purchase rights under this Warrant exist at the time shall have received, or, on or after the record date fixed for the determination of eligible stockholders, shall have become entitled to receive, without payment therefor, other or additional stock or other securities of the Company by way of dividend, then and in each case, this Warrant shall represent the right to acquire, in addition to the number of shares of the security receivable upon exercise of this Warrant, and without payment of any additional consideration therefor, the amount of such additional stock or other securities of the Company that such holder would hold on the date of such exercise had it been the holder of record of the security receivable upon exercise of this Warrant on the date hereof and had thereafter, during the period from the date hereof to and including the date of such exercise, retained such shares and/or all

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other additional stock available by it as aforesaid during such period, giving effect to all adjustments called for during such period by the provisions of this Section 12.

12.5 Certificate as to Adjustments. Upon the occurrence of each adjustment or readjustment pursuant to this Section 12, the Company at its expense shall promptly compute such adjustment or readjustment in accordance with the terms hereof and furnish to each Holder of this Warrant a certificate setting forth such adjustment or readjustment and showing in detail the facts upon which such adjustment or readjustment is based. The Company shall, upon the written request, at any time, of any such Holder, furnish or cause to be furnished to such Holder a like certificate setting forth: (i) such adjustments and readjustments; (ii) the Exercise Price at the time in effect; and (iii) the number of shares that at the time would be received upon the exercise of the Warrant.

13. [Reserved]

14. [Reserved].

15. Representations and Warranties of the Holder. The Holder hereby represents and warrants to the Company as follows:

15.1 Investment Intent. Holder has no intention of selling, granting any participation on or otherwise transferring this Warrant or the Common Stock issuable upon its exercise, and Holder does not have any contract, undertaking, agreement or arrangement with any person or entity to sell, transfer or grant participation to such person or entity or to any third person or entity with respect to this Warrant or the Common Stock issuable upon exercise of the Warrant. Such Holder understands that this Warrant and the Common Stock issuable upon exercise of this Warrant have not been and will not be registered under the Securities Act of 1933, as amended (the “Act”), by reason of a specific exemption from the registration of the Act, the availability of which depends upon, among other things, the bona fide nature of the investment intent and the accuracy of such Holder’s representations as expressed herein or otherwise made pursuant hereto.

15.2 Restricted Securities. Holder understands that this Warrant and the Common Stock issuable upon exercise of this Warrant are “restricted securities” under the Act and applicable state securities laws and that, pursuant to these laws, Holder must hold the Warrant and the Common Stock issuable upon exercise of the Warrant indefinitely unless they are registered with the Securities and Exchange Commission and qualified by state authorities or an exemption from such registration and qualification requirements is available. Holder acknowledges that neither this Warrant nor the Common Stock issuable upon exercise of this Warrant have been registered or qualified under the Act or the securities laws of any state and the Company has no obligation to register or qualify this Warrant or the Common Stock issuable upon exercise of this Warrant for resale except as set forth in the Investors’ Rights Agreement.

15.3 Accredited Investor Status. Holder represents to the Company that Holder is an Accredited Investor (as defined in the Act).

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16. Descriptive Headings and Governing Law. The description headings of the several sections and paragraphs of this Warrant are inserted for convenience only and do not constitute a part of this Warrant. This Warrant shall be construed and enforced in accordance with, and the rights of the parties shall be governed by, the laws of the State of California without regard to conflicts of law provisions.

17. Confidentiality. The Company hereby agrees to keep the terms and conditions of this Warrant confidential and the Holder shall keep confidential any and all information and materials provided by the Company to the Holder hereunder. Notwithstanding the foregoing confidentiality obligation, a party may disclose information relating to this Warrant as required by law, rule, regulation, court order or other legal authority, provided that (i) the disclosing party has given the other party prompt notice of such required disclosure, and (ii) the disclosing party only discloses information that is required, in the opinion of counsel reasonably satisfactory to the other party, to be disclosed.

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IN WITNESS WHEREOF, the parties have executed this Warrant as of the date set forth below.

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NOTICE OF EXERCISE

(1) The undersigned hereby elects to purchase      shares of Common Stock of Solazyme, Inc., pursuant to the provisions of Section 3(a) of the attached Warrant, and tenders herewith payment of the purchase price for such shares in full.

(2) In exercising this Warrant, the undersigned hereby confirms and acknowledges that the shares of Common Stock to be issued are being acquired solely for the account of the undersigned and not as a nominee for any other party, and for investment, and that the undersigned will not offer, sell or otherwise dispose of any such shares of Common Stock except under circumstances that will not result in a violation of the Securities Act of 1933, as amended, or any applicable state securities laws.

(3) Please issue a certificate or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:

(4) Please issue a new Warrant for the unexercised portion of the attached Warrant in the name of the undersigned or in such other name as is specified below:

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ASSIGNMENT FORM

FOR VALUE RECEIVED, the undersigned registered owner of this Warrant hereby sells, assigns and transfers unto the Assignee named below all of the rights of the undersigned under the within Warrant, with respect to the number of shares of Common Stock set forth below:

and does hereby irrevocably constitute and appoint                          Attorney to make such transfer on the books of Solazyme, Inc. maintained for the purpose, with full power of substitution in the premises.

The undersigned also represents that, by assignment hereof, the Assignee acknowledges that this Warrant and the shares of Common Stock to be issued upon exercise hereof are being acquired for investment and that the Assignee will not offer, sell or otherwise dispose of this Warrant or any shares of Common Stock to be issued hereof except under circumstances which will not result in a violation of the Securities Act of 1933, as amended, or any state securities laws. Further, the Assignee has acknowledged that upon exercise of this Warrant, the Assignee shall confirm in writing, in a form satisfactory to the Company, that the shares of Common Stock so purchased are being acquired for investment and not with a view toward distribution or resale.

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