Warrant to Purchase Common Stock of EXELIXIS, INC

Exhibit 4.9

[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

THIS WARRANT, THE SECURITIES ISSUABLE UPON EXERCISE HEREOF AND ANY FAILURE PAYMENT SHARES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAW, AND MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED OF OR EXERCISED UNLESS (I) A REGISTRATION STATEMENT REGISTERING SUCH SECURITIES UNDER THE SECURITIES ACT AND APPLICABLE STATE SECURITIES LAWS SHALL HAVE BECOME EFFECTIVE, OR (II) THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT SUCH TRANSFER MAY LAWFULLY BE MADE WITHOUT REGISTRATION UNDER THE SECURITIES ACT OR QUALIFICATION UNDER APPLICABLE STATE SECURITIES LAWS, OR (III) SUCH SECURITIES ARE SOLD PURSUANT TO RULE 144 OR RULE 144A.

AN INVESTMENT IN THESE SECURITIES INVOLVES A HIGH DEGREE OF RISK. HOLDERS MUST RELY ON THEIR OWN ANALYSIS OF THE INVESTMENT AND ASSESSMENT OF THE RISKS INVOLVED.

Warrant to Purchase Common Stock

of

EXELIXIS, INC.

THIS CERTIFIES that ____________ or any subsequent holder hereof has the right to purchase from EXELIXIS, INC., a Delaware corporation (the “Company”), ________ (              ) fully paid and nonassessable shares, of the Company’s common stock, $0.001 par value per share (“Common Stock”), subject to adjustment as provided herein, at a price equal to the Exercise Price as defined in Section 3 below, at any time during the Term (as defined below).

Holder agrees with the Company that this Warrant to Purchase Common Stock of the Company (this “Warrant” or this “Agreement”) is issued and all rights hereunder shall be held subject to all of the conditions, limitations and provisions set forth herein.

1. Date of Issuance and Term.

This Warrant shall be deemed to be issued on _____, 2008 (“Date of Issuance”). The term of this Warrant begins on the Date of Issuance and ends at 5:00 p.m., New York City time, on the date that is six (6) years after the Date of Issuance (the “Term”). This Warrant was issued in conjunction with that certain Facility Agreement (the “Facility Agreement”) and the Registration Rights Agreement (“Registration Rights Agreement”) by and between the Company and __________, each dated _____, 2008, entered into in conjunction herewith.

Notwithstanding anything herein to the contrary, the Company shall not issue to the Holder, and the Holder may not acquire, a number of shares of Common Stock upon exercise of this Warrant to the extent that, upon such exercise, the number of shares of Common Stock then beneficially owned by the Holder and its Affiliates and any other persons or entities whose beneficial ownership of Common Stock would be aggregated with the Holder’s for purposes of Section 13(d) of the Securities Exchange Act of 1934 (the “Exchange Act”) (including shares held by any “group” of which the Holder is a member, but excluding shares beneficially owned by virtue of the ownership of securities or rights to acquire securities that have limitations on the right to convert, exercise or purchase similar to the limitation set forth herein) would exceed 9.98% of the total number of shares of Common Stock then issued and outstanding (the “9.98% Cap”). For purposes hereof, “group” has the meaning set forth in Section 13(d) of the Exchange Act and applicable regulations of the Securities and Exchange Commission (the “SEC”), and the percentage held by the Holder shall be determined in a manner consistent with the provisions of Section 13(d) of the Exchange Act. Upon the written request of the Holder, the Company shall, within two (2) Trading Days confirm orally and in writing to the Holder the number of shares of Common Stock then outstanding.

[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

“Affiliate” means any person or entity that, directly or indirectly through one or more intermediaries, controls or is controlled by or is under common control with a person or entity, as such terms are used in and construed under Rule 144 under the Securities Act of 1933, as amended (the “Securities Act”). With respect to a Holder of Warrants, any investment fund or managed account that is managed on a discretionary basis by the same investment manager as such Holder will be deemed to be an Affiliate of such Holder.

“Business Day” means a day on which banks are open for business in The City of New York and San Francisco.

“Grace Period” shall have the meaning set forth in the Registration Rights Agreement.

“Holder” means ______ and any transferee or assignee pursuant to the terms of this Warrant.

“Initial Filing Deadline” shall have the meaning set forth in the Registration Rights Agreement.

“Initial Registration Deadline” shall have the meaning set forth in the Registration Rights Agreement.

“Initial Registration Statement” shall have the meaning set forth in the Registration Rights Agreement.

“Registrable Securities” shall have the meaning set forth in the Registration Rights Agreement.

“Registration” shall have the meaning set forth in the Registration Rights Agreement.

“Registration Period” shall have the meaning set forth in the Registration Rights Agreement.

“Registration Statement” shall have the meaning set forth in the Registration Rights Agreement.

“Trading Day” means any day on which the Common Stock is traded for at least two hours on NASDAQ, or on the principal securities exchange or other securities market on which the Common Stock is then being traded.

2. Exercise .

(a) Manner of Exercise. During the Term, this Warrant may be Exercised as to all or any lesser number of full shares of Common Stock covered hereby (the “Warrant Shares” or the “Shares”) upon surrender of this Warrant, with the Exercise Form attached hereto as Exhibit A (the “Exercise Form”) duly completed and executed, together with the full Exercise Price (as defined below, which may be satisfied by a Cash Exercise, a Cashless Exercise, a Cashless Major Exercise or a Cashless Default Exercise, as each is defined below) for each share of Common Stock as to which this Warrant is Exercised, at the office of the Company, Exelixis, Inc., 170 Harbor Way, P.O. Box 511, South San Francisco, CA 94083; Fax: (680) 837-7951, or at such other office or agency as the Company may designate in writing, by overnight mail, with an advance copy of the Exercise Form sent to the Company and the transfer agent for the Common Stock (“Transfer Agent”) by facsimile (such surrender and payment of the Exercise Price hereinafter called the “Exercise” of this Warrant).

(b) Date of Exercise. If any portion of the Exercise Price is satisfied by a Cash Exercise (as defined below), the “Date of Exercise” of the Warrant shall be defined as the later of (A) the date that the Exercise Form attached hereto as Exhibit A , completed and executed, is sent by facsimile to the Company, provided that the original Warrant and Exercise Form are received by the Company, each as soon as practicable thereafter (or, the date the original Exercise Form is received by the Company, if Holder has not sent advance notice by facsimile) and (B) the date that the Exercise Price is received by the Company. If no portion of the Exercise Price is satisfied by a Cash Exercise, the “Date of Exercise” of the Warrant shall be defined as the date that the Exercise Form attached hereto as Exhibit A , completed and executed, is sent by facsimile to the Company, provided that the original Warrant and Exercise Form are received by the Company, each as soon as practicable thereafter (or, the date the original Exercise Form is received by the Company, if Holder has not sent advance notice by facsimile).

(c) Delivery of Common Stock Upon Exercise. Within three (3) Trading Days after any Date of Exercise, or in the case of a Cashless Major Exercise or a Cashless Default Exercise (each as defined in Section 5(c)(i) below), within the period provided in Section 5(c)(iii) or Section 3(a)(iv), as applicable (the “Delivery Period”), the Company shall issue and deliver (or cause its Transfer Agent to so issue and deliver) in accordance with the terms hereof to or upon the order of the Holder that number of shares of Common Stock (“Exercise Shares”) for the portion of this Warrant exercised as shall be determined in accordance herewith. Upon the Exercise of this

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[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

Warrant or any part thereof, the Company shall, at its own cost and expense, take all reasonable steps, including obtaining and delivering, an opinion of counsel to assure that the Transfer Agent shall issue stock certificates in the name of Holder (or its nominee) or such other persons as designated by Holder and in such denominations to be specified at Exercise representing the number of shares of Common Stock issuable upon such Exercise.

(d) Delivery Failure. In addition to any other remedies which may be available to the Holder, in the event that the Company fails for any reason to effect delivery of the Exercise Shares by the end of the Delivery Period (a “Delivery Failure”), the Holder will be entitled to revoke all or part of the relevant Exercise Form by delivery of a notice to such effect to the Company whereupon the Company and the Holder shall each be restored to their respective positions immediately prior to the delivery of such notice, except that the liquidated damages described herein shall be payable through the date notice of revocation or rescission is given to the Company.

(i) Restrictive Legend . The Holder understands that this Warrant, the Exercise Shares and the Failure Payment Shares (as defined in Section 10 hereof) have not been registered on the Date of Issuance, under the Securities Act. The Holder understands that until such time as (i) this Warrant has been registered under the Securities Act and/or (ii) the Exercise Shares and/or the Failure Payment Shares, as applicable, have been registered under the Securities Act as contemplated by the Registration Rights Agreement, or otherwise may be sold pursuant to Rule 144 under the Securities Act or an exemption from registration under the Securities Act without any restriction as to the number of securities as of a particular date that can then be immediately sold, (A) this Warrant will bear a restrictive legend in substantially the form set forth on the first page of this Warrant (and a stop-transfer order may be placed against transfer of such securities) and (B) the Exercise Shares and the Failure Payment Shares will bear a restrictive legend in substantially the following form (and a stop-transfer order may be placed against transfer of the certificates for such securities):

“THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS. THE SECURITIES MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT FOR THE SECURITIES UNDER SAID ACT OR PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER SAID ACT INCLUDING, WITHOUT LIMITATION, PURSUANT TO RULES 144 OR 144A UNDER SAID ACT OR PURSUANT TO A PRIVATE SALE EFFECTED UNDER APPLICABLE FORMAL OR INFORMAL SEC INTERPRETATION OR GUIDANCE, SUCH AS A SO-CALLED “4(1) AND A HALF” SALE, SUBJECT TO DELIVERY OF AN OPINION, AS PROVIDED IN THE WARRANT.

“THE SALE, TRANSFER OR ASSIGNMENT OF THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO THE TERMS AND CONDITIONS OF A CERTAIN REGISTRATION RIGHTS AGREEMENT DATED AS OF June 4, 2008, AS AMENDED FROM TIME TO TIME. COPIES OF SUCH AGREEMENT MAY BE OBTAINED AT NO COST BY WRITTEN REQUEST MADE BY THE HOLDER OF RECORD OF THIS CERTIFICATE TO THE SECRETARY OF THE COMPANY.”

(ii) Removal of Restrictive Legends . This Warrant and certificates evidencing the Exercise Shares and any Failure Payment Shares shall not contain any legend restricting the transfer thereof (including any legend set forth above in subsection 2(e)(i)): (A) while a registration statement (including a Registration Statement) covering the sale or resale of such security is effective under the Securities Act, or (B) following any sale of such Warrant, Exercise Shares and/or Failure Payment Shares pursuant to Rule 144, or (C) if such Warrant, Exercise Shares and/or Failure Payment Shares are eligible for sale under Rule 144(b)(1), or (D) if such legend is not required under any other applicable requirements of the Securities Act (including judicial interpretations and pronouncements issued by the staff of the SEC) and the Company shall have received an opinion of counsel to the Holder in form reasonably acceptable to the Company to such effect, which, in the case of a so-called “4(1) and a half” sale, shall be in the form of Exhibit C hereto (collectively, the “Unrestricted Conditions”). If the Unrestricted Conditions are met, the Company shall cause its counsel to issue a legal opinion to the Transfer Agent if required by the Company’s transfer agent to effect the issuance of the Exercise Shares or any Failure Payment Shares, as applicable, without a restrictive legend or removal of the legend hereunder. If the Unrestricted Conditions are met at the time of issuance of this Warrant, the Exercise Shares and/or any Failure Payment Shares, then this Warrant, the Exercise Shares and/or any Failure Payment Shares, as applicable, shall be issued free of all legends. The Company agrees that at such time as the Unrestricted Conditions are met or such legend is otherwise no longer required under this Section 2(e), it will, no later than three (3) Trading Days following the delivery (the “Unlegended Shares Delivery Deadline”) by the Holder to the Company or the Transfer Agent of this Warrant and a certificate representing Exercise Shares or Failure Payment Shares, as applicable, issued with a restrictive legend (such third Trading Day, the “Legend Removal Date”), deliver or cause to be delivered to such Holder this Warrant and/or a certificate (or electronic transfer) representing such shares that is free from all restrictive and other legends.

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[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

(iii) Sale of Unlegended Shares . Holder agrees that the removal of the restrictive legend from this Warrant and any certificates representing securities as set forth in Section 2(e) above is predicated upon the Company’s reliance that the Holder would sell, transfer, assign, pledge, hypothecate or otherwise dispose of this Warrant, any Exercise Shares and/or any Failure Payment Shares pursuant to either the registration requirements of the Securities Act, including any applicable prospectus delivery requirements, or an exemption therefrom, and that if such securities are sold pursuant to a Registration Statement, they will be sold in compliance with the plan of distribution set forth therein.

(f) Cancellation of Warrant. This Warrant shall be canceled upon the full Exercise of this Warrant or upon full redemption of this Warrant. As soon as practical after the Date of Exercise, Holder shall be entitled to receive Common Stock for the number of shares purchased upon such Exercise of this Warrant as set forth in Section 2(c), and if this Warrant is not Exercised in full, Holder shall be entitled to receive a new Warrant (containing terms identical to this Warrant) representing any unexercised portion of this Warrant in addition to such Common Stock.

(g) Holder of Record. Each person in whose name any Warrant for shares of Common Stock is issued shall, for all purposes, be deemed to be the Holder of record of such shares on the Date of Exercise of this Warrant, irrespective of the date of delivery of the Common Stock purchased upon the Exercise of this Warrant or the date such Common Stock is credited to the Holder’s DTC account, as the case may be. Nothing in this Warrant shall be construed as conferring upon Holder any rights as a stockholder of the Company.

(h) Delivery of Electronic Shares. In lieu of delivering physical certificates representing the Common Stock issuable upon Exercise or legend removal or representing Failure Payment Shares, provided the Company’s Transfer Agent is participating in the Depository Trust Company (“DTC”) Fast Automated Securities Transfer (“FAST”) program, upon written request of the Holder, the Company shall use its commercially reasonable efforts to cause its Transfer Agent to electronically transmit the Common Stock issuable to the Holder by crediting the account of the Holder’s prime broker with DTC through its Deposit Withdrawal Agent Commission (DWAC) system. The time periods for delivery and penalties described herein shall apply to the electronic transmittals described herein. Any delivery not effected by electronic transmission shall be effected by delivery of physical certificates.

(i) Buy-In. In addition to any other rights available to the Holder, if the Company fails to cause its Transfer Agent to transmit to the Holder a certificate or certificates representing the Exercise Shares pursuant to an Exercise on or before the Delivery Period (other than a failure caused by any incorrect or incomplete information provided by Holder to the Company hereunder, and if after such date the Holder is required by its broker to purchase (in an open market transaction or otherwise) or the Holder’s brokerage firm otherwise purchases shares of Common Stock to deliver in satisfaction of a sale by the Holder of the Exercise Shares which the Holder anticipated receiving upon such Exercise (a “Buy-In”), then the Company shall (1) pay in cash to the Holder the amount by which (x) the Holder’s total purchase price (including brokerage commissions, if any) for the shares of Common Stock so purchased exceeds (y) the amount obtained by multiplying (A) the number of Exercise Shares that the Company was required to deliver to the Holder in connection with the Exercise at issue times and (B) the price at which the sell order giving rise to such purchase obligation was executed, and (2) at the option of the Holder, either reinstate the portion of the Warrant and equivalent number of Exercise Shares for which such Exercise was not honored or deliver to the Holder certificate(s) representing the number of shares of Common Stock that would have been issued had the Company timely complied with its Exercise and delivery obligations hereunder. For example, if the Holder purchases Common Stock having a total purchase price of $11,000 to cover a Buy-In with respect to an attempted Exercise to cover the sale of Common Stock with an aggregate sale price giving rise to such purchase obligation of $10,000, under subsection (1) of the immediately preceding sentence the Company shall be required to pay the Holder $1,000. The Holder shall provide the Company written notice indicating the amounts payable to the Holder in respect of the Buy-In, together with applicable confirmations and other evidence reasonably requested by the Company. Nothing herein shall limit a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity including, without limitation, a decree of specific performance and/or injunctive relief with respect to the Company’s failure to timely deliver certificates representing shares of Common Stock upon Exercise of the Warrant as required pursuant to the terms hereof.

3. Payment of Warrant Exercise Price .

(a) Exercise Price. The Exercise Price (“Exercise Price”) shall initially equal $____ per share subject to adjustment pursuant to the terms hereof, including but not limited to Section 5 below.

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[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

Payment of the Exercise Price may be made by either of the following, or a combination thereof, at the election of Holder:

(i) Cash Exercise: The Holder may exercise this Warrant in cash, bank or cashier’s check or wire transfer (a “Cash Exercise”); or

(ii) Cashless Exercise . The Holder, at its option, may exercise this Warrant in a cashless exercise transaction. In order to effect a Cashless Exercise, the Holder shall surrender this Warrant at the principal office of the Company together with the Exercise Form attached hereto as Exhibit A indicating that the Holder is exercising the Warrant pursuant to a cashless election, in which event the Company shall issue Holder a number of shares of Common Stock computed using the following formula (a “Cashless Exercise”):

X = Y (A-B)/A

where: X = the number of shares of Common Stock to be issued to Holder.

Y = the number of shares of Common Stock for which this Warrant is being Exercised.

A = the Market Price of one (1) share of Common Stock (for purposes of this Section 3(a)(ii), where “Market Price,” as of any date, means the Volume Weighted Average Price (as defined herein) of the Company’s Common Stock during the ten (10) consecutive Trading Day period immediately preceding the date in question.

B = the Exercise Price.

As used herein, the “Volume Weighted Average Price” for any security as of any date means the volume weighted average sale price on the NASDAQ Global Select Market or The NASDAQ Global Market (“NASDAQ”) as reported by, or based upon data reported by, Bloomberg Financial Markets or an equivalent, reliable reporting service mutually acceptable to and hereafter designated by holders of a majority in interest of the Warrants and the Company (“Bloomberg”) or, if NASDAQ is not the principal trading market for such security, the volume weighted average sale price of such security on the principal securities exchange or trading market where such security is listed or traded as reported by Bloomberg, or, if no volume weighted average sale price is reported for such security, then the last closing trade price of such security as reported by Bloomberg, or, if no last closing trade price is reported for such security by Bloomberg, the average of the bid prices of any market makers for such security that are listed in the over the counter market by the National Association of Securities Dealers or in the “pink sheets” by the National Quotation Bureau, Inc. If the Volume Weighted Average Price cannot be calculated for such security on such date in the manner provided above, the volume weighted average price shall be the fair market value as determined in good faith by the Company’s board of directors.

(iii) Cashless Major Exercise: To the extent the Holder shall exercise this Warrant or any portion thereof as a Cashless Major Exercise pursuant to Section 5(c)(i) below, the Holder shall surrender this Warrant at the principal office of the Company together with the Exercise Form indicating that the Holder is exercising this Warrant (or such portion thereof) pursuant to a Cashless Major Exercise, in which event the Company shall issue a number of shares of Common Stock equal to the Black-Scholes Value (as defined in Section 5(c)(iii) below) of the remaining unexercised portion of this Warrant (or such applicable portion being exercised) divided by [ * ] of the closing price of the Common Stock on the principal securities exchange or other securities market on which the Common Stock is then traded on the Trading Day immediately preceding the date on which the applicable Major Transaction is consummated.

(iv) Cashless Default Exercise . To the extent the Holder exercises this Warrant as a Cashless Default Exercise pursuant to Section 11(b)(i) below, the Holder shall surrender this Warrant to the principal office of the Company together with the Exercise Form indicating that the Holder is exercising this Warrant pursuant to a Cashless Default Exercise, in which event, unless the Company has exercised its right to effect a Mandatory Redemption in accordance with Section 11(b)(i), the Company shall issue to the Holder, within five (5) Trading Days of the delivery of such Exercise Form, a number of shares of Common Stock (which shares shall be valued at [ * ] of the Volume Weighted Average Price for the five (5) Trading Days prior to the applicable Default Notice) equal to the greater of (A) the Black-Scholes value (determined by use of the Black-Scholes Option Pricing Model using the criteria set forth on Schedule 1 hereto) of the remaining unexercised portion of this Warrant on the date of delivery of such Exercise Form and (B) the Black-Scholes value (determined by use of the Black-Scholes Option Pricing Model using the criteria set forth on Schedule 1 hereto) of the remaining unexercised portion of this Warrant on the Trading Day immediately preceding the date that the applicable Exercise Shares are issued to the Holder.

4. Transfer and Registration .

(a) Transfer Rights. Subject to the provisions of Section 8 of this Warrant, this Warrant may be transferred on the books of the Company, in whole or in part, in person or by attorney, upon surrender of this Warrant properly completed and endorsed. This Warrant shall be canceled upon such surrender and, as soon as practicable thereafter, the person to whom such transfer is made shall be entitled to receive a new Warrant or Warrants as to the portion of this Warrant transferred, and Holder shall be entitled to receive a new Warrant as to the portion hereof retained.

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[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

(b) Registrable Securities. The Exercise Shares and the Failure Payment Shares have registration rights pursuant to the Registration Rights Agreement.

5. Adjustments Upon Certain Events .

(a) Participation . The Holder, as the holder of this Warrant, shall be entitled to receive such dividends paid and distributions of any kind made to the holders of Common Stock of the Company to the same extent as if the Holder had Exercised this Warrant into Common Stock (without regard to any limitations on exercise herein or elsewhere and without regard to whether or not a sufficient number of shares are authorized and reserved to effect any such exercise and issuance) and had held such shares of Common Stock on the record date for such dividends and distributions. Payments under the preceding sentence shall be made concurrently with the dividend or distribution to the holders of Common Stock.

(b) Recapitalization or Reclassification. If the Company shall at any time effect a stock split, recapitalization, reclassification or other similar transaction of such character that the shares of Common Stock shall be changed into or become exchangeable for a larger or smaller number of shares, then upon the effective date thereof, the number of shares of Common Stock which Holder shall be entitled to purchase upon Exercise of this Warrant shall be increased or decreased, as the case may be, in direct proportion to the increase or decrease in the number of shares of Common Stock by reason of such stock split, recapitalization, reclassification or similar transaction, and the Exercise Price shall be, in the case of an increase in the number of shares, proportionally decreased and, in the case of decrease in the number of shares, proportionally increased. The Company shall give Holder the same notice it provides to holders of Common Stock of any transaction described in this Section 5(b).

(i) Major Transaction. To the extent that any Major Transaction will not be treated as an Assumption pursuant to the next following paragraph, then (1) in the case of a Cash-Out Major Transaction and in the case of a Mixed Major Transaction to the extent of the percentage of the cash consideration in the Mixed Major Transaction (determined in accordance with the definition of a Mixed Major Transaction below), the Holder shall have the right to require the Company to redeem the Holder’s outstanding Warrants (or the applicable portion in a Mixed Major Transaction) in accordance with Section 5(c)(iii) below and (2) in the case of all other Major Transactions and in the case of a Mixed Major Transaction to the extent of the percentage of the consideration represented by securities of a Successor Entity in the Mixed Major Transaction, the Holder shall have the right to exercise this Warrant as a Cashless Major Exercise. For the avoidance of doubt, in no event shall the Holder have the right to treat a Major Transaction as an Assumption unless the Company has elected to treat such Major Transaction as an Assumption pursuant to the next following paragraph. Notwithstanding anything herein to the contrary, and except as set forth in the next sentence, the Holder may elect to waive its rights under this Section 5(c)(i) with respect to any Major Transaction in which event none of the provisions contained in this Section 5(c)(i) shall apply. In the event of a Major Transaction in which all shares of Common Stock are cancelled and converted into the right to receive cash and/or securities of Another Entity (as defined below), then, any portion of this Warrant that is neither redeemed, assumed or exercised pursuant to the terms of this Warrant prior to the closing of such Major Transaction, shall (A) automatically and immediately convert into shares of Common Stock, and shall be deemed to have been exercised pursuant to a Cashless Exercise, immediately prior to the consummation of such Major Transaction if the aggregate consideration to be received for the Common Stock in such Major Transaction is greater than the aggregate Exercise Price for such shares, or (B) be cancelled and terminated without further action by the Holder or the Company upon consummation of such Major Transaction if the aggregate consideration to be received for the Common Stock in the Major Transaction is less than the aggregate Exercise Price for such shares.

In the event of a Qualified Major Transaction, the Company shall have the right to cause such Qualified Major Transaction (or the applicable portion of a Mixed Major Transaction) to be treated as an Assumption in accordance with Section 5(c)(ii) below with respect to the percentage of this Warrant then owned by the Holder equal to the percentage of the consideration to be paid in the Major Transaction represented by the securities of a Successor Entity. If the Successor Entity is a Publicly Traded Successor Entity, the percentage of consideration represented by securities of such Successor Entity shall be equal to the percentage that the value of the aggregate anticipated number of shares of the Publicly Traded Successor Entity to be issued to holders of Common Stock of the Company represents of the aggregate value of all consideration, including cash consideration, in such Major Transaction, as such values are set forth in any definitive agreement for the Major Transaction that has been executed at the time of the first public announcement of the Major Transaction or, if no such value is determinable from such definitive agreement, based on the closing market price for shares of the Publicly Traded Successor Entity on its principal securities exchange on the Trading Day preceding the first public announcement of the Major Transaction. If the Successor Entity is a Private Successor Entity, the percentage of consideration represented by securities of such Successor Entity shall be determined in good-faith by the Company’s Board of Directors. Any election by the Company to treat this Warrant as an Assumption pursuant to the terms hereof shall be made in the Major Transaction Notice (as defined in Section 5(a)(iii) below) in respect of such Qualified Major Transaction.

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[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

Consummation of each of the following events shall constitute a “Major Transaction”:

(A) a consolidation, merger, exchange of shares, recapitalization, reorganization, business combination or other similar event (in each case other than an event provided for in Section 5(b) above and other than a merger effected for purposes of changing the Company’s state of incorporation), (1) following which the holders of Common Stock immediately preceding such consolidation, merger, exchange, recapitalization, reorganization, combination or event either (a) no longer hold a majority of the shares of Common Stock or (b) no longer have the ability to elect a majority of the board of directors of the Company or (2) as a result of which shares of Common Stock shall be changed into (or the shares of Common Stock become entitled to receive) the same or a different number of shares of the same or another class or classes of stock or securities of another entity (collectively, a “Change of Control Transaction”);

(B) (1) the sale or transfer of assets in one transaction or a series of related transactions for a purchase price (excluding any consideration allocable to any Excluded Transaction) of more than $[ * ] million (the “Aggregate Consideration”) or (2) a sale or transfer of more than [ * ] of the Company’s assets; or

(C) a purchase, tender or exchange offer made to the holders of outstanding shares of Common Stock, such that following such purchase, tender or exchange offer a Change of Control Transaction shall have occurred and is consummated.

If the maximum aggregate consideration payable in a transaction or series of related transactions described in Section 5(c)(i)(B)(1) above (i) includes contingent payments related to future events, and (ii) exceeds the Aggregate Consideration ([ * ] described below), then for purposes of determining whether the Aggregate Consideration has been reached, the [ * ] of such contingent payments shall be determined prior to the public announcement of such transaction [ * ] the Company and the initial Holder hereof.

Notwithstanding the foregoing, none of the following (an “Excluded Transaction”) shall constitute a Major Transaction:

(x) entering into any collaborative arrangement, licensing agreement, [ * ] providing for the research, development or commercial exploitation of compounds, products or services that provides for the payments received therefrom or the Company’s income or profits to be shared with another Person, including, without limitation, (1) the grant, to an entity engaged in the pharmaceutical or biotechnology industry, of a license or option to obtain a license to any of the Company’s intellectual property or other assets, provided that [ * ] from such entity [ * ] by such entity in consideration of such grant (other than any payments [ * ], which consideration may, but need not, include (without limitation) upfront, milestone, royalty and profit-sharing payments, and (2) the grant of a license or option to obtain a license to, [ * ], the Company’s intellectual property or other assets to any entity that intends to research and develop or commercialize products or services covered by such intellectual property or embodying or arising from such other assets, whether directly or through the Company or another entity, provided that the Company or a wholly owned subsidiary of [ * ] or has the [ * ] that reasonably reflects the [ * ]; or

(y) the incurrence, grant or existence of, or any sale or transfer of any assets in connection with, any Permitted Lien (as defined in the Facility Agreement).

For purposes hereof:

“Another Entity” shall mean an entity in which the holders of a majority of the shares of Common Stock of the Company immediately prior to the consummation of a Major Transaction do not hold a majority of the equity securities in such entity.

“Cashless Default Exercise” shall mean an exercise of this Warrant as a “Cashless Default Exercise” in accordance with Section 3(a)(iv) and 11(b) hereof.

“Cashless Major Exercise” shall mean an exercise of this Warrant or portion thereof as a “Cashless Major Exercise” in accordance with Section 3(a)(iii) and 5(c)(i) hereof.

“Cash-Out Major Transaction” means a Major Transaction in which the consideration payable to holders of Common Stock in connection with the Major Transaction consists solely of cash.

“Eligible Market” means the over the counter Bulletin Board, the New York Stock Exchange, Inc., the NYSE Arca, the NASDAQ Capital Market, the NASDAQ Global Market, the NASDAQ Global Select Market or the American Stock Exchange.

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[ * ] = Certain confidential information contained in this document, marked by brackets, is filed with the Securities and Exchange Commission pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

“Mixed Major Transaction” means a Major Transaction in which the consideration payable to holders of Common Stock consists partially of cash and partially of securities of a Successor Entity. If the Successor Entity is a Publicly Traded Successor Entity, the percentage of consideration represented by securities of such Successor Entity shall be equal to the percentage that the value of the aggregate anticipated number of shares of the Publicly Traded Successor Entity to be issued to holders of Common Stock of the Company represents of the aggregate value of all consideration, including cash consideration, in such Mixed Major Transaction, as such values are set forth in any definitive agreement for the Mixed Major Transaction that has been executed at the time of the first public announcement of the Major Transaction or, if no such value is determinable from such definitive agreement, based on the closing market price for shares of the Publicly Traded Successor Entity on its principal securities exchange on the Trading Day preceding the first public announcement of the Mixed Major Transaction. If the Successor Entity is a Private Successor Entity, the percentage of consideration represented by securities of such Successor Entity shall be determined in good-faith by the Company’s Board of Directors.

A “Parent Entity” of a Person means an entity that, directly or indirectly, controls the applicable Person and whose common stock or equivalent equity security is quoted or listed on an Eligible Market, or, if there is more than one such Person or Parent Entity, the Person or Parent Entity with the largest public market capitalization as of the date of consummation of a Major Transaction.

“Person” means an individual, a limited liability company, a partnership, a joint venture, a corporation, a trust, an unincorporated organization, any other entity and a government or any department