Exhibit 4.1

[FORM OF SUBSCRIPTION UNIT]

MARINA BIOTECH, INC.

SUBSCRIPTION INVESTMENT UNIT TO PURCHASE COMMON STOCK

Subscription Unit No.:             

Date of Issuance: November 5, 2010 (“Issuance Date”)

Marina Biotech, Inc., a Delaware corporation (the “Company”), hereby certifies that, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, [                    ], the registered holder hereof or its permitted assigns (the “Holder”), is entitled, subject to the terms set forth below, to purchase from the Company, at the Exercise Price (as defined below) then in effect, upon exercise of this Subscription Investment Unit to Purchase Common Stock (including any Subscription Investment Units to Purchase Common Stock issued in exchange, transfer or replacement hereof, the “Subscription Unit”), at any time or times on or after the Issuance Date, but not after 11:59 p.m., New York time, on the Expiration Date (as defined below), [                    ] (subject to adjustment as provided herein) fully paid and non-assessable shares of Common Stock (as defined below) (the “Unit Shares”). Except as otherwise defined herein, capitalized terms in this Subscription Unit shall have the meanings set forth in Section 17. This Subscription Unit is one of the Subscription Investment Units to Purchase Common Stock (the “SPA Units”) issued pursuant to Section 1 of that certain Securities Purchase Agreement, dated as of November 4, 2010, by and among the Company and the investors (the “Buyers”) referred to therein (the “Securities Purchase Agreement”).

1. EXERCISE OF SUBSCRIPTION UNIT.

(a) Mechanics of Exercise. Subject to the terms and conditions hereof (including, without limitation, the limitations set forth in Section 1(f)), this Subscription Unit may be exercised by the Holder on any day on or after the Issuance Date, in whole or in part, by delivery (whether via facsimile or otherwise) of a written notice, in the form attached hereto as Exhibit A (the “Exercise Notice”, and such date, the “Exercise Date”), of the Holder’s election to exercise this Subscription Unit. Within one (1) Trading Day following an exercise of this Subscription Unit as aforesaid, the Holder shall deliver payment to the Company of an amount equal to the Exercise Price in effect on the date of such exercise multiplied by the number of Unit Shares as to which this Subscription Unit was so exercised (the “Aggregate Exercise Price”) in cash or via wire transfer of immediately available funds if the Holder did not notify the Company in such Exercise Notice that such exercise was made pursuant to a Cashless Exercise (as defined in Section 1(d)). The Holder shall not be required to deliver the original of this Subscription Unit in order to effect an exercise hereunder. Execution and delivery of an Exercise Notice with respect to less than all of the Unit Shares shall have the same effect as cancellation of the original of this Subscription Unit and issuance of a new Subscription Unit evidencing the right to purchase the remaining number of Unit Shares. Execution and delivery of an Exercise Notice for all of the then-remaining Unit Shares shall have the same effect as cancellation of the original of this Subscription Unit after delivery of the Unit Shares in accordance with the terms hereof. On or

before the first (1^st) Trading Day following the date on which the Company has received an Exercise Notice, the Company shall transmit by facsimile an acknowledgment of confirmation of receipt of such Exercise Notice, in the form attached hereto as Exhibit B, to the Holder and the Company’s transfer agent (the “Transfer Agent”). On or before the third (3^rd) Trading Day following the date on which the Company has received such Exercise Notice, the Company shall (X) provided that the Transfer Agent is participating in The Depository Trust Company (“DTC”) Fast Automated Securities Transfer Program, upon the request of the Holder, credit such aggregate number of shares of Common Stock to which the Holder is entitled pursuant to such exercise to the Holder’s or its designee’s balance account with DTC through its Deposit/ Withdrawal at Custodian system, or (Y) if the Transfer Agent is not participating in the DTC Fast Automated Securities Transfer Program, issue and deliver to the Holder or, at the Holder’s instruction pursuant to the Exercise Notice, the Holder’s agent or designee, in each case, sent by reputable overnight courier to the address as specified in the applicable Exercise Notice, a certificate, registered in the Company’s share register in the name of the Holder or its designee (as indicated in the applicable Exercise Notice), for the number of shares of Common Stock to which the Holder is entitled pursuant to such exercise. Upon delivery of an Exercise Notice, the Holder shall be deemed for all corporate purposes to have become the holder of record of the Unit Shares with respect to which this Subscription Unit has been exercised, irrespective of the date such Unit Shares are credited to the Holder’s DTC account or the date of delivery of the certificates evidencing such Unit Shares (as the case may be). If this Subscription Unit is submitted in connection with any exercise pursuant to this Section 1(a) and the number of Unit Shares represented by this Subscription Unit submitted for exercise is greater than the number of Unit Shares being acquired upon an exercise, then, at the request of the Holder, the Company shall as soon as practicable and in no event later than three (3) Business Days after any exercise and at its own expense, issue and deliver to the Holder (or its designee) a new Subscription Unit (in accordance with Section 7(d)) representing the right to purchase the number of Unit Shares purchasable immediately prior to such exercise under this Subscription Unit, less the number of Unit Shares with respect to which this Subscription Unit is exercised. No fractional shares of Common Stock are to be issued upon the exercise of this Subscription Unit, but rather the number of shares of Common Stock to be issued shall be rounded up to the nearest whole number. The Company shall pay any and all taxes and fees which may be payable with respect to the issuance and delivery of Unit Shares upon exercise of this Subscription Unit. Notwithstanding the foregoing, except in the case where an exercise of this Subscription Unit is validly made pursuant to a Cashless Exercise (as defined in Section 1(d)), the Company’s failure to deliver Unit Shares to the Holder on or prior to the second (2nd) Trading Day after the Company’s receipt of the Aggregate Exercise Price shall not be deemed to be a breach of this Subscription Unit

(b) Exercise Price. For purposes of this Subscription Unit, “Exercise Price” means, as of any Exercise Date, the lesser of (i) $2.21 (the “Fixed Exercise Price”), and (ii) 90% of the quotient of (x) the sum of the three lowest VWAP of the Common Stock of any three Trading Days during the ten (10) consecutive Trading Day period ending and including the Trading Day immediately prior to the applicable Exercise Date, divided by (y) three (3), subject to adjustment as provided herein.

(c) Company’s Failure to Timely Deliver Securities. If the Company shall fail, for any reason or for no reason, to issue to the Holder within the later of (i) three (3) Trading Days

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after receipt of the applicable Exercise Notice and (ii) two (2) Trading Days after the Company’s receipt of the Aggregate Exercise Price (or valid notice of a Cashless Exercise) (such later date, the “Share Delivery Deadline”), a certificate for the number of shares of Common Stock to which the Holder is entitled and register such shares of Common Stock on the Company’s share register or to credit the Holder’s balance account with DTC for such number of shares of Common Stock to which the Holder is entitled upon the Holder’s exercise of this Subscription Unit (as the case may be) , then, in addition to all other remedies available to the Holder, the Company shall pay in cash to the Holder on each day after such third (3^rd) Trading Day that the issuance of such shares of Common Stock is not timely effected an amount equal to 2% of the product of (A) the aggregate number of shares of Common Stock not issued to the Holder on a timely basis and to which the Holder is entitled and (B) the Closing Sale Price of the Common Stock on the Trading Day immediately preceding the last possible date on which the Company could have issued such shares of Common Stock to the Holder without violating Section 1(a). In addition to the foregoing, if on or prior to the Share Delivery Deadline, the Company shall fail to issue and deliver a certificate to the Holder and register such shares of Common Stock on the Company’s share register or credit the Holder’s balance account with DTC for the number of shares of Common Stock to which the Holder is entitled upon the Holder’s exercise hereunder (as the case may be), and if on or after such Share Delivery Deadline the Holder purchases (in an open market transaction or otherwise) shares of Common Stock to deliver in satisfaction of a sale by the Holder of shares of Common Stock issuable upon such exercise that the Holder anticipated receiving from the Company, then, in addition to all other remedies available to the Holder, the Company shall, within three (3) Business Days after the Holder’s request and in the Holder’s discretion, either (i) pay cash to the Holder in an amount equal to the Holder’s total purchase price (including brokerage commissions, if any) for the shares of Common Stock so purchased (the “Buy-In Price”), at which point the Company’s obligation to deliver such certificate or credit the Holder’s balance account with DTC for the number of shares of Common Stock to which the Holder is entitled upon the Holder’s exercise hereunder (as the case may be) (and to issue such shares of Common Stock) shall terminate, or (ii) promptly honor its obligation to deliver to the Holder a certificate or certificates representing such shares of Common Stock or credit the Holder’s balance account with DTC for the number of shares of Common Stock to which the Holder is entitled upon the Holder’s exercise hereunder (as the case may be) and pay cash to the Holder in an amount equal to the excess (if any) of the Buy-In Price over the product of (A) such number of shares of Common Stock times (B) the Closing Sale Price of the Common Stock on the Trading Day immediately preceding the date of the applicable Exercise Notice.

(d) Cashless Exercise. Notwithstanding anything contained herein to the contrary (other than Section 1(f) below), if at the time of exercise hereof the Registration Statement (as defined in the Securities Purchase Agreement) is not effective (or the prospectus contained therein is not available for use) for the issuance by the Company to the Holder of all of the Unit Shares, then the Holder may, in its sole discretion, exercise this Subscription Unit in whole or in part and, in lieu of making the cash payment otherwise contemplated to be made to the Company upon such exercise in payment of the Aggregate Exercise Price, elect instead to receive upon such exercise the “Net Number” of shares of Common Stock determined according to the following formula (a “Cashless Exercise”):

Net Number = (A x B) - (A x C)

                        B

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For purposes of the foregoing formula:

A= the total number of shares with respect to which this Subscription Unit is then being exercised.

B= as applicable: (i) the Closing Sale Price of the Common Stock on the Trading Day immediately preceding the date of the applicable Exercise Notice if such Exercise Notice is (1) both executed and delivered pursuant to Section 1(a) hereof on a day that is not a Trading Day or (2) both executed and delivered pursuant to Section 1(a) hereof on a Trading Day prior to the opening of “regular trading hours” (as defined in Rule 600(b)(64) of Regulation NMS promulgated under the federal securities laws) on such Trading Day, (ii) the Bid Price of the Common Stock as of the time of the Holder’s execution of the applicable Exercise Notice if such Exercise Notice is executed during “regular trading hours” on a Trading Day and is delivered within two (2) hours thereafter pursuant to Section 1(a) hereof or (iii) the Closing Sale Price of the Common Stock on the date of the applicable Exercise Notice if the date of such Exercise Notice is a Trading Day and such Exercise Notice is both executed and delivered pursuant to Section 1(a) hereof after the close of “regular trading hours” on such Trading Day.

C= the Exercise Price then in effect for the applicable Unit Shares at the time of such exercise.

(e) Disputes. In the case of a dispute as to the determination of the Exercise Price or the arithmetic calculation of the number of Unit Shares to be issued pursuant to the terms hereof, the Company shall promptly issue to the Holder the number of Unit Shares that are not disputed and resolve such dispute in accordance with Section 13.

(f) Limitations on Exercises. Notwithstanding anything to the contrary contained in this Subscription Unit, this Subscription Unit shall not be exercisable by the Holder hereof to the extent (but only to the extent) that the Holder or any of its affiliates would beneficially own in excess of 4.9% (the “Maximum Percentage”) of the Common Stock. To the extent the above limitation applies, the determination of whether this Subscription Unit shall be exercisable (vis-à-vis other convertible, exercisable or exchangeable securities owned by the Holder or any of its affiliates) and of which such securities shall be exercisable (as among all such securities owned by the Holder) shall, subject to such Maximum Percentage limitation, be determined on the basis of the first submission to the Company for conversion, exercise or exchange (as the case may be). No prior inability to exercise this Subscription Unit pursuant to this paragraph shall have any effect on the applicability of the provisions of this paragraph with respect to any subsequent determination of exercisability. For the purposes of this paragraph, beneficial ownership and all determinations and calculations (including, without limitation, with respect to calculations of percentage ownership) shall be determined in accordance with Section 13(d) of the 1934 Act (as defined in the Securities Purchase Agreement) and the rules and regulations promulgated thereunder. The provisions of this paragraph shall be implemented in a manner otherwise than in strict conformity with the terms of this paragraph to correct this paragraph (or any portion

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hereof) which may be defective or inconsistent with the intended Maximum Percentage beneficial ownership limitation herein contained or to make changes or supplements necessary or desirable to properly give effect to such Maximum Percentage limitation. The limitations contained in this paragraph shall apply to a successor Holder of this Subscription Unit. The holders of Common Stock shall be third party beneficiaries of this paragraph and the Company may not waive this paragraph without the consent of holders of a majority of its Common Stock. For any reason at any time, upon the written or oral request of the Holder, the Company shall within one (1) Business Day confirm orally and in writing to the Holder the number of shares of Common Stock then outstanding, including by virtue of any prior conversion or exercise of convertible or exercisable securities into Common Stock, including, without limitation, pursuant to this Subscription Unit or securities issued pursuant to the Securities Purchase Agreement. [By written notice to the Company, any Holder may increase or decrease the Maximum Percentage to any other percentage not in excess of 9.99% specified in such notice; provided that (i) any such increase will not be effective until the 61st day after such notice is delivered to the Company, and (ii) any such increase or decrease will apply only to the Holder sending such notice and not to any other holder of SPA Units.]

(g) Insufficient Authorized Shares. The Company shall at all times keep reserved for issuance under this Subscription Unit a number of shares of Common Stock as shall be necessary to satisfy the Company’s obligation to issue shares of Common Stock hereunder (without regard to any limitation otherwise contained herein with respect to the number of shares of Common Stock that may be acquirable upon exercise of this Subscription Unit). If, notwithstanding the foregoing, and not in limitation thereof, at any time while any of the SPA Units remain outstanding the Company does not have a sufficient number of authorized and unreserved shares of Common Stock to satisfy its obligation to reserve for issuance upon exercise of the SPA Units at least a number of shares of Common Stock equal to the number of shares of Common Stock as shall from time to time be necessary to effect the exercise of all of the SPA Units then outstanding (the “Required Reserve Amount”) (an “Authorized Share Failure”), then the Company shall immediately take all action necessary to increase the Company’s authorized shares of Common Stock to an amount sufficient to allow the Company to reserve the Required Reserve Amount for all the SPA Units then outstanding. Without limiting the generality of the foregoing sentence, as soon as practicable after the date of the occurrence of an Authorized Share Failure, but in no event later than sixty (60) days after the occurrence of such Authorized Share Failure, the Company shall hold a meeting of its stockholders for the approval of an increase in the number of authorized shares of Common Stock. In connection with such meeting, the Company shall provide each stockholder with a proxy statement and shall use its best efforts to solicit its stockholders’ approval of such increase in authorized shares of Common Stock and to cause its board of directors to recommend to the stockholders that they approve such proposal.

2. ADJUSTMENT OF EXERCISE PRICE AND NUMBER OF UNIT SHARES. The Fixed Exercise Price and number of Unit Shares issuable upon exercise of this Subscription Unit are subject to adjustment from time to time as set forth in this Section 2.

(a) Stock Dividends and Splits. Without limiting any provision of Section 4, if the Company, at any time on or after the date of the Securities Purchase Agreement, (i) pays a stock

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dividend on one or more classes of its then outstanding shares of Common Stock or otherwise makes a distribution on any class of capital stock that is payable in shares of Common Stock, (ii) subdivides (by any stock split, stock dividend, recapitalization or otherwise) one or more classes of its then outstanding shares of Common Stock into a larger number of shares or (iii) combines (by combination, reverse stock split or otherwise) one or more classes of its then outstanding shares of Common Stock into a smaller number of shares, then in each such case the Fixed Exercise Price shall be multiplied by a fraction of which the numerator shall be the number of shares of Common Stock outstanding immediately before such event and of which the denominator shall be the number of shares of Common Stock outstanding immediately after such event. Any adjustment made pursuant to clause (i) of this paragraph shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend or distribution, and any adjustment pursuant to clause (ii) or (iii) of this paragraph shall become effective immediately after the effective date of such subdivision or combination. If any event requiring an adjustment under this paragraph occurs during the period that an Fixed Exercise Price is calculated hereunder, then the calculation of such Fixed Exercise Price shall be adjusted appropriately to reflect such event.

(b) Number of Unit Shares. Simultaneously with any adjustment to the Fixed Exercise Price pursuant to paragraph (a) of this Section 2, the number of Unit Shares that may be purchased upon exercise of this Subscription Unit shall be increased or decreased proportionately, so that after such adjustment the aggregate Fixed Exercise Price payable hereunder for the adjusted number of Unit Shares shall be the same as the aggregate Fixed Exercise Price in effect immediately prior to such adjustment (without regard to any limitations on exercise contained herein).

(c) Calculations. All calculations under this Section 2 shall be made by rounding to the nearest cent or the nearest 1/100^th of a share, as applicable. The number of shares of Common Stock outstanding at any given time shall not include shares owned or held by or for the account of the Company, and the disposition of any such shares shall be considered an issue or sale of Common Stock.

3. RIGHTS UPON DISTRIBUTION OF ASSETS. In addition to any adjustments pursuant to Section 2 above, if the Company shall declare or make any dividend or other distribution of its assets (or rights to acquire its assets) to holders of shares of Common Stock, by way of return of capital or otherwise (including, without limitation, any distribution of cash, stock or other securities, property or options by way of a dividend, spin off, reclassification, corporate rearrangement, scheme of arrangement or other similar transaction) (a “Distribution”), at any time after the issuance of this Subscription Unit, then, in each such case, the Holder shall be entitled to participate in such Distribution to the same extent that the Holder would have participated therein if the Holder had held the number of shares of Common Stock acquirable upon complete exercise of this Subscription Unit (without regard to any limitations on exercise hereof, including without limitation, the Maximum Percentage) immediately before the date on which a record is taken for such Distribution, or, if no such record is taken, the date as of which the record holders of shares of Common Stock are to be determined for the participation in such Distribution (provided, however, to the extent that the Holder’s right to participate in any such Distributions would result in the Holder exceeding the Maximum Percentage, then the Holder shall not be entitled to participate in such Distribution to such extent (or the beneficial ownership

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of any such shares of Common Stock as a result of such Distribution to such extent) and such Distribution to such extent shall be held in abeyance for the benefit of the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding the Maximum Percentage).

4. PURCHASE RIGHTS; FUNDAMENTAL TRANSACTIONS.

(a) Purchase Rights. In addition to any adjustments pursuant to Section 2 above, if at any time the Company grants, issues or sells any Options, Convertible Securities or rights to purchase stock, warrants, securities or other property pro rata to the record holders of any class of shares of Common Stock (the “Purchase Rights”), then the Holder will be entitled to acquire, upon the terms applicable to such Purchase Rights, the aggregate Purchase Rights which the Holder could have acquired if the Holder had held the number of shares of Common Stock acquirable upon complete exercise of this Subscription Unit (without regard to any limitations on exercise hereof, including without limitation, the Maximum Percentage) immediately before the date on which a record is taken for the grant, issuance or sale of such Purchase Rights, or, if no such record is taken, the date as of which the record holders of shares of Common Stock are to be determined for the grant, issue or sale of such Purchase Rights (provided, however, to the extent that the Holder’s right to participate in any such Purchase Right would result in the Holder exceeding the Maximum Percentage, then the Holder shall not be entitled to participate in such Purchase Right to such extent (or beneficial ownership of such shares of Common Stock as a result of such Purchase Right to such extent) and such Purchase Right to such extent shall be held in abeyance for the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding the Maximum Percentage).

(b) Fundamental Transactions. The Company shall not enter into or be party to a Fundamental Transaction unless (i) the Successor Entity assumes in writing all of the obligations of the Company under this Subscription Unit and the other Transaction Documents (as defined in the Securities Purchase Agreement) in accordance with the provisions of this Section 4(b) pursuant to written agreements in form and substance satisfactory to the Holder and approved by the Holder prior to such Fundamental Transaction, including agreements to deliver to the Holder in exchange for this Subscription Unit a security of the Successor Entity evidenced by a written instrument substantially similar in form and substance to this Subscription Unit, including, without limitation, which is exercisable for a corresponding number of shares of capital stock equivalent to the shares of Common Stock acquirable and receivable upon exercise of this Subscription Unit (without regard to any limitations on the exercise of this Subscription Unit) prior to such Fundamental Transaction, and with an exercise price which applies the exercise price hereunder to such shares of capital stock (but taking into account the relative value of the shares of Common Stock pursuant to such Fundamental Transaction and the value of such shares of capital stock, such adjustments to the number of shares of capital stock and such exercise price being for the purpose of protecting the economic value of this Subscription Unit immediately prior to the consummation of such Fundamental Transaction) and (ii) the Successor Entity (including its Parent Entity) is a publicly traded corporation whose common stock is quoted on or listed for trading on an Eligible Market. Upon the consummation of each Fundamental Transaction, the Successor Entity shall succeed to, and be substituted for (so that from and after the date of the applicable Fundamental Transaction, the provisions of this Subscription Unit and the other Transaction Documents referring to the “Company” shall refer instead to the Successor Entity), and may exercise every right and power of the Company and

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shall assume all of the obligations of the Company under this Subscription Unit and the other Transaction Documents with the same effect as if such Successor Entity had been named as the Company herein. Upon consummation of each Fundamental Transaction, the Successor Entity shall deliver to the Holder confirmation that there shall be issued upon exercise of this Subscription Unit at any time after the consummation of the applicable Fundamental Transaction, in lieu of the shares of Common Stock (or other securities, cash, assets or other property (except such items still issuable under Sections 3 and 4(a) above, which shall continue to be receivable thereafter)) issuable upon the exercise of this Subscription Unit prior to the applicable Fundamental Transaction, such shares of publicly traded common stock (or its equivalent) of the Successor Entity (including its Parent Entity) which the Holder would have been entitled to receive upon the happening of the applicable Fundamental Transaction had this Subscription Unit been exercised immediately prior to the applicable Fundamental Transaction (without regard to any limitations on the exercise of this Subscription Unit), as adjusted in accordance with the provisions of this Subscription Unit. Notwithstanding the foregoing, and without limiting Section 1(f) hereof, the Holder may elect, at its sole option, by delivery of written notice to the Company to waive this Section 4(b) to permit the Fundamental Transaction without the assumption of this Subscription Unit. In addition to and not in substitution for any other rights hereunder, prior to the consummation of each Fundamental Transaction pursuant to which holders of shares of Common Stock are entitled to receive securities or other assets with respect to or in exchange for shares of Common Stock (a “Corporate Event”), the Company shall make appropriate provision to insure that the Holder will thereafter have the right to receive upon an exercise of this Subscription Unit at any time after the consummation of the applicable Fundamental Transaction but prior to the Expiration Date, in lieu of the shares of the Common Stock (or other securities, cash, assets or other property (except such items still issuable under Sections 3 and 4(a) above, which shall continue to be receivable thereafter)) issuable upon the exercise of the Subscription Unit prior to such Fundamental Transaction, such shares of stock, securities, cash, assets or any other property whatsoever (including warrants or other purchase or subscription rights) which the Holder would have been entitled to receive upon the happening of the applicable Fundamental Transaction had this Subscription Unit been exercised immediately prior to the applicable Fundamental Transaction (without regard to any limitations on the exercise of this Subscription Unit). Provision made pursuant to the preceding sentence shall be in a form and substance reasonably satisfactory to the Holder.

(c) Black Scholes Value. Notwithstanding the foregoing and the provisions of Section 4(b) above, at the request of the Holder delivered at any time commencing on the earlier to occur of (i) the public disclosure of any Change of Control or (ii) the consummation of any Change of Control through the date that is ninety (90) days after the later to occur of (x) the public disclosure of such Change of Control, (y) the consummation of such Change of Control and (z) the Holder becoming aware of such Change of Control if such Change of Control was not publicly disclosed, the Company or the Successor Entity (as the case may be) shall purchase this Subscription Unit from the Holder on the date of such request by paying to the Holder cash in an amount equal to the Black Scholes Value.

(d) Application. The provisions of this Section 4 shall apply similarly and equally to successive Fundamental Transactions and Corporate Events and shall be applied as if this Subscription Unit (and any such subsequent subscription units) were fully exercisable and without regard to any limitations on the exercise of this Subscription Unit (provided that the

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Holder shall continue to be entitled to the benefit of the Maximum Percentage, applied however with respect to shares of capital stock registered under the 1934 Act and thereafter receivable upon exercise of this Subscription Unit (or any such other subscription units)).

5. NONCIRCUMVENTION. The Company hereby covenants and agrees that the Company will not, by amendment of its Articles of Incorporation (as defined in the Securities Purchase Agreement), Bylaws (as defined in the Securities Purchase Agreement) or through any reorganization, transfer of assets, consolidation, merger, scheme of arrangement, dissolution, issue or sale of securities, or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Subscription Unit, and will at all times in good faith carry out all the provisions of this Subscription Unit and take all action as may be required to protect the rights of the Holder. Without limiting the generality of the foregoing, the Company (i) shall not increase the par value of any shares of Common Stock receivable upon the exercise of this Subscription Unit above the Exercise Price then in effect, (ii) shall take all such actions as may be necessary or appropriate in order that the Company may validly and legally issue fully paid and non-assessable shares of Common Stock upon the exercise of this Subscription Unit, and (iii) shall, so long as any of the SPA Units are outstanding, take all action necessary to reserve and keep available out of its authorized and unissued shares of Common Stock, solely for the purpose of effecting the exercise of the SPA Units, the maximum number of shares of Common Stock as shall from time to time be necessary to effect the exercise of the SPA Units then outstanding (without regard to any limitations on exercise).

6. HOLDER NOT DEEMED A STOCKHOLDER. Except as otherwise specifically provided herein, the Holder, solely in its capacity as a holder of this Subscription Unit, shall not be entitled to vote or receive dividends or be deemed the holder of share capital of the Company for any purpose, nor shall anything contained in this Subscription Unit be construed to confer upon the Holder, solely in its capacity as the Holder of this Subscription Unit, any of the rights of a stockholder 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, prior to the issuance to the Holder of the Unit Shares which it is then entitled to receive upon the due exercise of this Subscription Unit. In addition, nothing contained in this Subscription Unit shall be construed as imposing any liabilities on the Holder to purchase any securities (upon exercise of this Subscription Unit or otherwise) or as a stockholder of the Company, whether such liabilities are asserted by the Company or by creditors of the Company. Notwithstanding this Section 6, the Company shall provide the Holder with copies of the same notices and other information given to the stockholders of the Company generally, contemporaneously with the giving thereof to the stockholders.

7. REISSUANCE OF SUBSCRIPTION UNITS.

(a) Transfer of Subscription Unit. If this Subscription Unit is to be transferred, the Holder shall surrender this Subscription Unit to the Company, whereupon the Company will forthwith issue and deliver upon the order of the Holder a new Subscription Unit (in accordance with Section 7(d)), registered as the Holder may request, representing the right to purchase the number of Unit Shares being transferred by the Holder and, if less than the total number of Unit Shares then underlying this Subscription Unit is being transferred, a new Subscription Unit (in accordance with Section 7(d)) to the Holder representing the right to purchase the number of Unit Shares not being transferred.

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(b) Lost, Stolen or Mutilated Subscription Unit. Upon receipt by the Company of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Subscription Unit (as to which a written certification and the indemnification contemplated below shall suffice as such evidence), and, in the case of loss, theft or destruction, of any indemnification undertaking by the Holder to the Company in customary and reasonable form and, in the case of mutilation, upon surrender and cancellation of this Subscription Unit, the Company shall execute and deliver to the Holder a new Subscription Unit (in accordance with Section 7(d)) representing the right to purchase the Unit Shares then underlying this Subscription Unit.

(c) Exchangeable for Multiple Subscription Units. This Subscription Unit is exchangeable, upon the surrender hereof by the Holder at the principal office of the Company, for a new Subscription Unit or Subscription Units (in accordance with Section 7(d)) representing in the aggregate the right to purchase the number of Unit Shares then underlying this Subscription Unit, and each such new Subscription Unit will represent the right to purchase such portion of such Unit Shares as is designated by the Holder at the time of such surrender; provided, however, no subscription investment units for fractional shares of Common Stock shall be given.

(d) Issuance of New Subscription Units. Whenever the Company is required to issue a new Subscription Unit pursuant to the terms of this Subscription Unit, such new Subscription Unit (i) shall be of like tenor with this Subscription Unit, (ii) shall represent, as indicated on the face of such new Subscription Unit, the right to purchase the Unit Shares then underlying this Subscription Unit (or in the case of a new Subscription Unit being issued pursuant to Section 7(a) or Section 7(c), the Unit Shares designated by the Holder which, when added to the number of shares of Common Stock underlying the other new Subscription Units issued in connection with such issuance, does not exceed the number of Unit Shares then underlying this Subscription Unit), (iii) shall have an issuance date, as indicated on the face of such new Subscription Unit which is the same as the Issuance Date, and (iv) shall have the same rights and conditions as this Subscription Unit.

8. NOTICES. Whenever notice is required to be given under this Subscription Unit, unless otherwise provided herein, such notice shall be given in accordance with Section 8(f) of the Securities Purchase Agreement. The Company shall provide the Holder with prompt written notice of all actions taken pursuant to this Subscription Unit, including in reasonable detail a description of such action and the reason therefor. Without limiting the generality of the foregoing, the Company will give written notice to the Holder (i) immediately upon each adjustment of the Exercise Price and the number of Unit Shares, setting forth in reasonable detail, and certifying, the calculation of such adjustment(s) and (ii) at least fifteen (15) days prior to the date on which the Company closes its books or takes a record (A) with respect to any dividend or distribution upon the shares of Common Stock, (B) with respect to any grants, issuances or sales of any Options, Convertible Securities or rights to purchase stock, warrants, securities or other property to holders of shares of Common Stock or (C) for determining rights to vote with respect to any Fundamental Transaction, dissolution or liquidation, provided in each

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case that such information shall be made known to the public prior to or in conjunction with such notice being provided to the Holder and (iii) at least ten (10) Trading Days prior to the consummation of any Fundamental Transaction. To the extent that any notice provided hereunder constitutes, or contains, material, non-public information regarding the Company or any of its Subsidiaries, the Company shall simultaneously file such notice with the SEC (as defined in the Securities Purchase Agreement) pursuant to a Current Report on Form 8-K. It is expressly understood and agreed that the time of execution specified by the Holder in each Exercise Notice shall be definitive and may not be disputed or challenged by the Company.

9. AMENDMENT AND WAIVER. Except as otherwise provided herein, the provisions of this Subscription Unit (other than Section 1(f)) may be amended and the Company may take any action herein prohibited, or omit to perform any act herein required to be performed by it, only if the Company has obtained the written consent of the Holder. No waiver shall be effective unless it is in writing and signed by an authorized representative of the waiving party.

10. SEVERABILITY. If any provision of this Subscription Unit is prohibited by law or otherwise determined to be invalid or unenforceable by a court of competent jurisdiction, the provision that would otherwise be prohibited, invalid or unenforceable shall be deemed amended to apply to the broadest extent that it would be valid and enforceable, and the invalidity or unenforceability of such provision shall not affect the validity of the remaining provisions of this Subscription Unit so long as this Subscription Unit as so modified continues to express, without material change, the original intentions of the parties as to the subject matter hereof and the prohibited nature, invalidity or unenforceability of the provision(s) in question does not substantially impair the respective expectations or reciprocal obligations of the parties or the practical realization of the benefits that would otherwise be conferred upon the parties. The parties will endeavor in good faith negotiations to replace the prohibited, invalid or unenforceable provision(s) with a valid provision(s), the effect of which comes as close as possible to that of the prohibited, invalid or unenforceable provision(s).

11. GOVERNING LAW. This Subscription Unit shall be governed by and construed and enforced in accordance with, and all questions concerning the construction, validity, interpretation and performance of this Subscription Unit shall be governed by, the internal laws of the State of New York, without giving effect to any choice of law or conflict of law provision or rule (whether of the State of New York or any other jurisdictions) that would cause the application of the laws of any jurisdictions other than the State of New York. The Company hereby irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in The City of New York, Borough of Manhattan, for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein, and hereby irrevocably waives, and agrees not to assert in any suit, action or proceeding, any claim that it is not personally subject to the jurisdiction of any such court, that such suit, action or proceeding is brought in an inconvenient forum or that the venue of such suit, action or proceeding is improper. Nothing contained herein shall be deemed to limit in any way any right to serve process in any manner permitted by law. Nothing contained herein shall be deemed or operate to preclude the Holder from bringing suit or taking other legal action against the Company in any other jurisdiction to collect on the Company’s obligations to the Holder or to enforce a judgment or other court ruling in favor of the Holder. THE COMPANY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE TO, AND AGREES NOT TO

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REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN CONNECTION WITH OR ARISING OUT OF THIS SUBSCRIPTION UNIT OR ANY TRANSACTION CONTEMPLATED HEREBY.

12. CONSTRUCTION; HEADINGS. This Subscription Unit shall be deemed to be jointly drafted by the Company and the Holder and shall not be construed against any Person as the drafter hereof. The headings of this Subscription Unit are for convenience of reference and shall not form part of, or affect the interpretation of, this Subscription Unit. Terms used in this Subscription Unit but defined in the other Transaction Documents shall have the meanings ascribed to such terms on the Closing Date (as defined in the Securities Purchase Agreement) in such other Transaction Documents unless otherwise consented to in writing by the Holder.

13. DISPUTE RESOLUTION. In the case of a dispute as to the determination of the Exercise Price, the Closing Sale Price, the Bid Price or fair market value or the arithmetic calculation of the Unit Shares (as the case may be), the Company or the Holder (as the case may be) shall submit the disputed determinations or arithmetic calculations (as the case may be) via facsimile (i) within two (2) Business Days after receipt of the applicable notice giving rise to such dispute to the Company or the Holder (as the case may be) or (ii) if no notice gave rise to such dispute, at any time after the Holder learned of the circumstances giving rise to such dispute (including, without limitation, as to whether any issuance or sale or deemed issuance or sale was an issuance or sale or deemed issuance or sale of Excluded Securities). If the Holder and the Company are unable to agree upon such determination or calculation (as the case may be) of the Exercise Price, the Closing Sale Price, the Bid Price or fair market value or the number of Unit Shares (as the case may be) within three (3) Business Days of such disputed determination or arithmetic calculation being submitted to the Company or the Holder (as the case may be), then the Company shall, within two (2) Business Days submit via facsimile (a) the disputed determination of the Exercise Price, the Closing Sale Price, the Bid Price or fair market value (as the case may be) to an independent, reputable investment bank selected by the Holder or (b) the disputed arithmetic calculation of the Unit Shares to the Company’s independent, outside accountant. The Company shall cause at its expense the investment bank or the accountant (as the case may be) to perform the determinations or calculations (as the case may be) and notify the Company and the Holder of the results no later than ten (10) Business Days from the time it receives such disputed determinations or calculations (as the case may be). Such investment bank’s or accountant’s determination or calculation (as the case may be) shall be binding upon all parties absent demonstrable error.

14. REMEDIES, CHARACTERIZATION, OTHER OBLIGATIONS, BREACHES AND INJUNCTIVE RELIEF. The remedies provided in this Subscription Unit shall be cumulative and in addition to all other remedies available under this Subscription Unit and the other Transaction Documents, at law or in equity (including a decree of specific performance and/or other injunctive relief), and nothing herein shall limit the right of the Holder to pursue actual damages for any failure by the Company to comply with the terms of this Subscription Unit. The Company covenants to the Holder that there shall be no characterization concerning this instrument other than as expressly provided herein. Amounts set forth or provided for herein with respect to payments, exercises and the like (and the computation thereof) shall be the amounts to be received by the Holder and shall not, except as expressly provided herein, be subject to any other obligation of the Company (or the performance thereof). The Company

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acknowledges that a breach by it of its obligations hereunder will cause irreparable harm to the Holder and that the remedy at law for any such breach may be inadequate. The Company therefore agrees that, in the event of any such breach or threatened breach, the holder of this Subscription Unit shall be entitled, in addition to all other available remedies, to an injunction restraining any breach, without the necessity of showing economic loss and without any bond or other security being required. The Company shall provide all information and documentation to the Holder that is requested by the Holder to enable the Holder to confirm the Company’s compliance with the terms and conditions of this Subscription Unit (including, without limitation, compliance with Section 2 hereof). The issuance of shares and certificates for shares as contemplated hereby upon the exercise of this Subscription Unit shall be made without charge to the Holder or such shares for any issuance tax or other costs in respect thereof, provided that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any certificate in a name other than the Holder or its agent on its behalf.

15. TRANSFER. This Subscription Unit may be offered for sale, sold, transferred or assigned without the consent of the Company.

16. MANDATORY EXERCISE. If at any time after the later of (x) 120 calendar days after the Issuance Date and (y) such date after which the Company has initially satisfied all of the Equity Conditions (the “Mandatory Exercise Eligibility Date”), (i) the Common Stock trades at a price equal to or greater than $4.78 per share (as adjusted for stock splits, stock combinations and the like occurring from and after the Issuance Date) (the “Trigger Price”) for a period of ten (10) consecutive Trading Days following the Mandatory Exercise Eligibility Date (the ten (10) consecutive Trading Days on which the condition in this clause (i) is satisfied are referred to herein as the “Mandatory Exercise Measuring Period”), (ii) the average daily volume (as reported on Bloomberg) of the Common Stock on the applicable Eligible Market for each Trading Day during the Mandatory Exercise Measuring Period exceeds 400,000 shares of Common Stock per day and (iii) no Equity Conditions Failure shall have occurred, then the Company shall have the right to require the Holder to exercise all, but not less than all, of this Subscription Unit for all of the then-remaining Unit Shares in accordance with Section 1 hereof (a “Mandatory Exercise”). The Company may exercise its right to require exercise under this Section 16 on one occasion by delivering (provided that all of the conditions set forth in clauses (i) through (iii) above are then satisfied), on the first (1^st) Trading Day immediately following the end of the Mandatory Exercise Measuring Period, a written notice thereof by facsimile and overnight courier to the Holder (the “Mandatory Exercise Notice” and the date the Holder receives such notice by facsimile is referred to as the “Mandatory Exercise Notice Date”). The Mandatory Exercise Notice shall be irrevocable. The Mandatory Exercise Notice shall (1) state the Trading Day selected for the Mandatory Exercise in accordance with this Section 16, which Trading Day shall be at least five (5) Trading Days but not more than fifteen (15) Trading Days following the Mandatory Exercise Notice Date (the “Mandatory Exercise Date”), (2) state the number of shares of Common Stock to be issued to the Holder on the Mandatory Exercise Date, (3) contain a certification from the Chief Executive Officer of the Company that there has been no Equity Conditions Failure and (4) contain a certification from the Chief Executive Officer of the Company that the Company has simultaneously taken the same action with respect to all of the SPA Units. Any portion of this Subscription Unit exercised by the Holder after the Mandatory Exercise Notice Date shall reduce the number of Unit Shares for which this

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Subscription Unit is required to be exercised on the Mandatory Exercise Date. If the Company has elected a Mandatory Exercise, the mechanics of exercise set forth in Section 1 shall apply, to the extent applicable, as if the Company had received from the Holder on the Mandatory Exercise Date an Exercise Notice with respect to all of the then-remaining Unit Shares. Notwithstanding anything contained in this Section 16 to the contrary, if (I) any shares of Common Stock trade for a price less than the Trigger Price on any day during the period commencing on the Mandatory Exercise Notice Date and ending on the Trading Day immediately preceding the Mandatory Exercise Date; (II) the average daily volume (as reported on Bloomberg) of the Common Stock on the applicable Eligible Market on any Trading Day during the period commencing on the Mandatory Exercise Notice Date and ending on the Trading Day immediately preceding the Mandatory Exercise Date is less than 400,000 shares of Common Stock; or (III) an Equity Conditions Failure occurs on any day during the period commencing on the Mandatory Exercise Notice Date and ending on the Mandatory Exercise Date which has not been waived in writing by the Holder, then, in either case, the Mandatory Exercise Notice delivered to the Holder shall be null and void ab initio and the Mandatory Exercise shall not occur. If the Company elects to cause a Mandatory Exercise of this Subscription Unit pursuant to this Section 16, then it must simultaneously take the same action with respect to all of the other SPA Units.

17. CERTAIN DEFINITIONS. For purposes of this Subscription Unit, the following terms shall have the following meanings:

(a) “Bid Price” means, for any security as of the particular time of determination, the bid price for such security on the Principal Market as reported by Bloomberg as of such time of determination, or, if the Principal Market is not the principal securities exchange or trading market for such security, the bid price of such security on the principal securities exchange or trading market where such security is listed or traded as reported by Bloomberg as of such time of determination, or if the foregoing does not apply, the bid price of such security in the over-the-counter market on the electronic bulletin board for such security as reported by Bloomberg as of such time of determination, or, if no bid price is reported for such security by Bloomberg as of such time of determination, the average of the bid prices of any market makers for such security as reported in the “pink sheets” by Pink Sheets LLC (formerly the National Quotation Bureau, Inc.) as of such time of determination. If the Bid Price cannot be calculated for a security as of the particular time of determination on any of the foregoing bases, the Bid Price of such security as of such time of determination shall be the fair market value as mutually determined by the Company and the Holder. If the Company and the Holder are unable to agree upon the fair market value of such security, then such dispute shall be resolved in accordance with the procedures in Section 13. All such determinations shall be appropriately adjusted for any stock dividend, stock split, stock combination or other similar transaction during such period.

(b) “Black Scholes Value” means the value of the unexercised portion of this Subscription Unit remaining on the date of the Holder’s request pursuant to Section 4(c), which value is calculated using the Black Scholes Option Pricing Model obtained from the “OV” function on Bloomberg utilizing (i) an underlying price per share equal to the greater of (1) the highest Closing Sale Price of the Common Stock during the period beginning on the Trading Day immediately preceding the earlier to occur of the public disclosure or consummation of the applicable Change of Control and ending on the Trading Day of the Holder’s request pursuant to

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Section 4(c) and (2) the sum of the price per share being offered in cash in the applicable Change of Control (if any) plus the value of the non-cash consideration being offered in the applicable Change of Control (if any), (ii) a strike price equal to the Exercise Price in effect on the of date of the Holder’s request pursuant to Section 4(c), (iii) a risk-free interest rate corresponding to the U.S. Treasury rate for a period equal to the greater of (1) the remaining term of this Subscription Unit as of the date of the Holder’s request pursuant to Section 4(c) and (2) the remaining term of this Subscription Unit as of the date of consummation of the applicable Change of Control or as of the date of the Holder’s request pursuant to Section 4(c) if such request is prior to the date of the consummation of the applicable Change of Control and (iv) an expected volatility equal to the greater of 100% and the 30 day volatility obtained from the HVT function on Bloomberg (determined utilizing a 365 day annualization factor) as of the Trading Day immediately following the earlier to occur of the public disclosure or consummation of the applicable Change of Control.

(c) “Bloomberg” means Bloomberg, L.P.

(d) “Business Day” means any day other than Saturday, Sunday or other day on which commercial banks in The City of New York are authorized or required by law to remain closed.

(e) “Change of Control” means any Fundamental Transaction other than (A) any merger of the Company or any of its direct or indirect wholly-owned Subsidiaries with or into any of the foregoing Persons, (B) any reorganization, recapitalization or reclassification of the Common Stock, in which holders of the Company’s voting power immediately prior to such reorganization, recapitalization or reclassification continue after such reorganization, recapitalization or reclassification to hold publicly traded securities and, directly or indirectly, the voting power of the surviving entity or entities necessary to elect a majority of the members of the board of directors (or their equivalent if other than a corporation) of such entity or entities, (C) pursuant to a migratory merger effected solely for the purpose of changing the jurisdiction of incorporation of the Company or (D) a merger in connection with a bona fide acquisition by the Company of any Person in which (x) the gross consideration paid, directly or indirectly, by the Company in such acquisition is not greater than 45% of the Company’s market capitalization as calculated on each of (1) the date of the public announcement of such merger and (2) the date of the consummation of such merger and (y) such merger does not contemplate any change to the identity of the board of directors of the Company or any of the members of the senior management of the Company, including, without limitation, the chief executive officer and the chief financial officer of the Company.

(f) “Closing Sale Price” means, for any security as of any date, the last closing trade price for such security on the Principal Market, as reported by Bloomberg, or, if the Principal Market begins to operate on an extended hours basis and does not designate the closing trade price, then the last trade price of such security prior to 4:00:00 p.m., New York time, as reported by Bloomberg, or, if the Principal Market is not the principal securities exchange or trading market for such security, the last trade 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 the foregoing does not apply, the last trade price of such security in the over-the-counter market on the electronic bulletin board for such security as reported by Bloomberg, or, if no last trade price

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is reported for such security by Bloomberg, the average of the ask prices of any market makers for such security as reported in the “pink sheets” by Pink Sheets LLC (formerly the National Quotation Bureau, Inc.). If the Closing Sale Price cannot be calculated for a security on a particular date on any of the foregoing bases, the Closing Sale Price of such security on such date shall be the fair market value as mutually determined by the Company and the Holder. If the Company and the Holder are unable to agree upon the fair market value of such security, then such dispute shall be resolved in accordance with the procedures in Section 13. All such determinations shall be appropriately adjusted for any stock dividend, stock split, stock combination or other similar transaction during such period.

(g) “Common Stock” means (i) the Company’s shares of common stock, $0.006 par value per share, and (ii) any capital stock into which such common stock shall have been changed or any share capital resulting from a reclassification of such common stock.

(h) “Convertible Securities” means any stock or other security (other than Options) that is at any time and under any circumstances, directly or indirectly, convertible into, exercisable or exchangeable for, or which otherwise entitles the holder thereof to acquire, any shares of Common Stock.

(i) “Eligible Market” means The New York Stock Exchange, the NYSE Amex LLC, the Nasdaq Global Select Market, or the Principal Market.

(j) “Equity Conditions” means: (i) on each day during the period beginning one month prior to the applicable date of determination and ending on and including the applicable date of determination the Registration Statement shall be available for the resale by the Holder of all of the Unit Shares (disregarding any limitation on exercise of this Subscription Unit); (ii) on each day during the period beginning three months prior to the applicable date of determination and ending on and including the applicable date of determination (the “Equity Conditions Measuring Period”), the Common Stock and the Unit Shares are listed or designated for quotation (as applicable) on an Eligible Market and shall not have been suspended from trading on an Eligible Market (other than suspensions of not more than two (2) days and occurring prior to the applicable date of determination due to business announcements by the Company) nor shall delisting or suspension by an Eligible Market have been threatened (with a reasonable prospect of delisting occurring) or pending either (A) in writing by such Eligible Market or (B) by falling below the minimum listing maintenance requirements of the Eligible Market on which the Common Stock is then listed or designated for quotation (as applicable); (iii) on each day during the Equity Conditions Measuring Period, the Company shall have delivered all shares of Common Stock issuable upon exercise of the SPA Units on a timely basis as set forth in Section 1(a) hereof and all other shares of capital stock required to be delivered by the Company on a timely basis as set forth in the other Transaction Documents; (iv) any shares of Common Stock to be issued in connection with the event requiring determination may be issued in full without violating Section 1(f) hereof; (v) any shares of Common Stock to be issued in connection with the event requiring determination may be issued in full without violating the rules or regulations of the Eligible Market on which the Common Stock is then listed or designated for quotation (as applicable); (vi) on each day during the Equity Conditions Measuring Period, no public announcement of a pending, proposed or intended Fundamental Transaction shall have occurred which has not been abandoned, terminated or consummated; (vii) the Company shall have no

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knowledge of any fact that would reasonably be expected to cause the Registration Statement not be effective or the prospectus contained therein to not be available for the resale of all of the shares of Common Stock issuable upon exercise of the SPA Units (disregarding any limitation on exercise of the SPA Units); (viii) the Holder shall not be in (and no other Buyer shall be in) possession of any material, non-public information provided to any of them by the Company, any of its affiliates or any of their respective employees, officers, representatives, agents or the like; and (ix) on each day during the Equity Conditions Measuring Period, the Company otherwise shall have been in compliance with each, and shall not have breached any material provision, covenant, representation or warranty of any Transaction Document.

(k) “Equity Conditions Failure” means that on any day during the period commencing ten (10) Trading Days prior to the Mandatory Exercise Notice Date through the Mandatory Exercise Date, the Equity Conditions have not been satisfied (or waived in writing by the Holder).

(l) “Expiration Date” means the date that is the sixteen month anniversary of the Issuance Date or, if such date falls on a day other than a Business Day or on which trading does not take place on the Principal Market (a “Holiday”), the next date that is not a Holiday.

(m) “Fundamental Transaction” means that (i) the Company or any of its Subsidiaries shall, directly or indirectly, in one or more related transactions, (1) consolidate or merge with or into (whether or not the Company or any of its Subsidiaries is the surviving corporation) any other Person, or (2) sell, lease, license, assign, transfer, convey or otherwise dispose of all or substantially all of its respective properties or assets to any other Person, or (3) allow any other Person to make a purchase, tender or exchange offer that is accepted by the holders of more than 50% of the outstanding shares of Voting Stock of the Company (not including any shares of Voting Stock of the Company held by the Person or Persons making or party to, or associated or affiliated with the Persons making or party to, such purchase, tender or exchange offer), or (4) consummate a stock or share purchase agreement or other business combination (including, without limitation, a reorganization, recapitalization, spin-off or scheme of arrangement) with any other Person whereby such other Person acquires more than 50% of the outstanding shares of Voting Stock of the Company (not including any shares of Voting Stock of the Company held by the other Person or other Persons making or party to, or associated or affiliated with the other Persons making or party to, such stock or share purchase agreement or other business combination), or (5) (I) reorganize, recapitalize or reclassify the Common Stock, (II) effect or consummate a stock combination, reverse stock split or other similar transaction involving the Common Stock or (III) make any public announcement or disclosure with respect to any stock combination, reverse stock split or other similar transaction involving the Common Stock (including, without limitation, any public announcement or disclosure of (x) any potential, possible or actual stock combination, reverse stock split or other similar transaction involving the Common Stock or (y) board or stockholder approval thereof, or the intention of the Company to seek board or stockholder approval of any stock combination, reverse stock split or other similar transaction involving the Common Stock), or (ii) any “person” or “group” (as these terms are used for purposes of Sections 13(d) and 14(d) of the 1934 Act and the rules and regulations promulgated thereunder) is or shall become the “beneficial owner” (as defined in Rule 13d-3 under the 1934 Act), directly or indirectly, of 50% of the aggregate ordinary voting power represented by issued and outstanding Voting Stock of the Company.

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(n) “Options” means any rights, warrants or options to subscribe for or purchase shares of Common Stock or Convertible Securities.

(o) “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 the Fundamental Transaction.

(p) “Person” means an individual, a limited liability company, a partnership, a joint venture, a corporation, a trust, an unincorporated organization, any other entity or a government or any department or agency thereof.

(q) “Principal Market” means the Nasdaq Global Market.

(r) “Successor Entity” means the Person (or, if so elected by the Holder, the Parent Entity) formed by, resulting from or surviving any Fundamental Transaction or the Person (or, if so elected by the Holder, the Parent Entity) with which such Fundamental Transaction shall have been entered into.

(s) “Trading Day” means any day on which the Common Stock is traded on the Principal Market, or, if the Principal Market is not the principal trading market for the Common Stock, then on the principal securities exchange or securities market on which the Common Stock is then traded, provided that “Trading Day” shall not include any day on which the Common Stock is scheduled to trade on such exchange or market for less than 4.5 hours or any day that the Common Stock is suspended from trading during the final hour of trading on such exchange or market (or if such exchange or market does not designate in advance the closing time of trading on such exchange or market, then during the hour ending at 4:00:00 p.m., New York time) unless such day is otherwise designated as a Trading Day in writing by the Holder.

(t) “Voting Stock” of a Person means capital stock of such Person of the class or classes pursuant to which the holders thereof have the general voting power to elect, or the general power to appoint, at least a majority of the board of directors, managers or trustees of such Person (irrespective of whether or not at the time capital stock of any other class or classes shall have or might have voting power by reason of the happening of any contingency).

(u) “VWAP” means, for any security as of any date, the dollar volume-weighted average price for such security on the Principal Market (or, if the Principal Market is not the principal trading market for such security, then on the principal securities exchange or securities market on which such security is then traded) during the period beginning at 9:30:01 a.m., New York time, and ending at 4:00:00 p.m., New York time, on such date as reported by Bloomberg through its “Volume at Price” function or, if the foregoing does not apply, the dollar volume-weighted average price of such security in the over-the-counter market on the electronic bulletin board for such security during the period beginning at 9:30:01 a.m., New York time, and ending at 4:00:00 p.m., New York time, on such date as reported by Bloomberg, or, if no dollar volume-weighted average price is reported for such security by Bloomberg for such hours, the average of the highest closing bid price and the lowest closing ask price of any of the market makers for

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such security as reported in the “pink sheets” by Pink Sheets LLC (formerly the National Quotation Bureau, Inc.). If VWAP cannot be calculated for such security on such date on any of the foregoing bases, the VWAP of such security on such date shall be the fair market value as mutually determined by the Company and the Holder. If the Company and the Holder are unable to agree upon the fair market value of such security, then such dispute shall be resolved in accordance with the procedures in Section 13. All such determinations shall be appropriately adjusted for any stock dividend, stock split, stock combination or other similar transaction during such period.

[signature page follows]

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IN WITNESS WHEREOF, the Company has caused this Subscription Investment Unit to Purchase Common Stock to be duly executed as of the Issuance Date set out above.

EXHIBIT A

EXERCISE NOTICE

TO BE EXECUTED BY THE REGISTERED HOLDER TO EXERCISE THIS

SUBSCRIPTION INVESTMENT UNIT TO PURCHASE COMMON STOCK

MARINA BIOTECH, INC.

The undersigned holder hereby exercises the right to purchase                                          of the shares of Common Stock (“Unit Shares”) of Marina Biotech, Inc., a Delaware corporation (the “Company”), evidenced by Subscription Investment Unit to Purchase Common Stock No.              (the “Subscription Unit”). Capitalized terms used herein and not otherwise defined shall have the respective meanings set forth in the Subscription Unit.

1. Form of Exercise Price. The Holder intends that payment of the Exercise Price shall be made as:

In the event that the Holder has elected a Cashless Exercise with respect to some or all of the Unit Shares to be issued pursuant hereto, the Holder hereby represents and warrants that (i) this Exercise Notice was executed by the Holder at              [a.m.][p.m.] on the date set forth below and (ii) if applicable, the Bid Price as of such time of execution of this Exercise Notice was $            .

2. Payment of Exercise Price. In the event that the Holder has elected a Cash Exercise with respect to some or all of the Unit Shares to be issued pursuant hereto, the Holder shall pay the Aggregate Exercise Price in the sum of $             to the Company in accordance with the terms of the Subscription Unit.

3. Delivery of Unit Shares. The Company shall deliver to Holder, or its designee or agent as specified below,              Unit Shares in accordance with the terms of the Subscription Unit. Delivery shall be made to Holder, or for its benefit, to the following address:

EXHIBIT B

ACKNOWLEDGMENT

The Company hereby acknowledges this Exercise Notice and hereby directs                      to issue the above indicated number of shares of Common Stock in accordance with the Transfer Agent Instructions dated November     , 2010, from the Company and acknowledged and agreed to by                     .