Void after 5:00 p.m. Central Standard Time, on December 31, 2012 Warrant to Purchase 714,285 Shares of Common Stock. WARRANT TO PURCHASE COMMON STOCK OF SPECTRASCIENCE, INC.

Exhibit
      4.3

THIS
      WARRANT HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF1933 (THE "ACT")
      NOR
      UNDER ANY STATE SECURITIES LAW AND MAY NOT BE PLEDGED, SOLD, ASSIGNED OR
      OTHERWISE TRANSFERRED UNTIL (1) A REGISTRATION STATEMENT UNDER THE ACT AND
      ANY
      APPLICABLE STATE SECURITIES LAW HAS BECOME EFFECTIVE WITH RESPECT THERETO,
      OR
      (2)RECEIPT BY THE COMPANY OF AN OPINION OF COUNSEL TO THE COMPANY TO THE EFFECT
      THAT REGISTRATION UNDER THE ACT OR APPLICABLE STATE SECURITIES LAW IS NOT
      REQUIRED IN CONNECTION WITH THE PROPOSED TRANSFER.

Void
      after 5:00 p.m. Central Standard Time, on December 31, 2012
Warrant
      to Purchase 714,285 Shares of Common Stock.
WARRANT
      TO PURCHASE COMMON STOCK
OF
SPECTRASCIENCE, INC.

This
      is
      to Certify That, FOR VALUE RECEIVED, Advanced Equities, Inc. ("Holder") is
      entitled to purchase, subject to the provisions of this Warrant, from
      SpectraScience, Inc., a Minnesota corporation ("Company"), 714,285 fully paid,
      validly issued and nonassessable shares of Common Stock, $0.01 par value per
      share, of the Company ("Common Stock") at an initial price of $0.80 per share
      at
      any time or from time to time during the period from the date hereof to 5:00
      p.m. Central Standard Time, on December 31, 2012. The number of shares of Common
      Stock to be received upon the exercise of this Warrant and the price to be
      paid
      for each share of Common Stock may be adjusted from time to time as hereinafter
      set forth. The exercise price and the number of shares issuable upon exercise
      of
      the Warrants will be proportionately adjusted for stock splits, stock dividends,
      recapitalizations and similar transactions. The shares of Common Stock
      deliverable upon such exercise, and as adjusted from time to time, are
      hereinafter sometimes referred to as "Warrant Shares" and the exercise price
      of
      a share of Common Stock in effect at any time and as adjusted from time to
      time
      is hereinafter sometimes referred to as the "Exercise Price".


      

          
            
            
            (a)
            EXERCISE
                OF WARRANT.

          

    

(1)
       This
      Warrant may be exercised in whole or in part at any time or from time to time
      on
      or after the date hereof and until 5:00 p.m. Central Standard Time on December
      13, 2012; provided, however, that if either such day is a day on which banking
      institutions in the State of Illinois are authorized by law to close, then
      on
      the next succeeding day which shall not be such a day. This Warrant may be
      exercised by presentation and surrender hereof to the Company at its principal
      office with the Purchase Form annexed hereto duly executed and accompanied
      by
      payment of the Exercise Price for the number of Warrant Shares specified in
      such
      form. As soon as practicable after each such exercise of the warrants, but
      not
      later than seven (7) days from the date of such exercise, the Company shall
      issue and deliver to the Holder a certificate or certificate for the Warrant
      Shares issuable upon such exercise, registered in the name of the Holder or
      its
      designee. If this Warrant should be exercised in part only, the Company shall,
      upon surrender of this Warrant for cancellation, execute and deliver a new
      Warrant evidencing the rights of the Holder thereof to purchase the balance
      of
      the Warrant Shares purchasable thereunder. Upon receipt by the Company of this
      Warrant at its office in proper form for exercise, the Holder shall be deemed
      to
      be the holder of record of the shares of Common Stock issuable upon such
      exercise, notwithstanding that the stock transfer books of the Company shall
      then be closed or that certificates representing such shares of Common Stock
      shall not then be physically delivered to the Holder.


        

        

          
        

        
 
(2)
       In
      lieu
      of delivering the Exercise Price in cash or check the Holder may elect to
      receive shares equal to the value of the Warrant or portion thereof being
      exercised ("Net Issue Exercise"). If the Holder wishes to elect the Net Issue
      Exercise, the Holder shall notify the Company of its election in writing at
      the
      time it delivers to the Company the Purchase Form. In the event the Holder
      shall
      elect Net Issue Exercise, the Holder shall receive the number of shares of
      Common Stock equal to the product of (a) the number of shares of Common Stock
      purchasable under the Warrant, or portion thereof being exercised, and (b)
      the
      current market value, as defined in paragraph (c), of one share of Common Stock
      minus the Exercise Price, divided by (c) the current market value, as defined
      below, of one share of Common Stock.


      

          
            
            
            (b)
            RESERVATION
                OF SHARES. The Company shall at all times reserve for issuance and/or
                delivery upon exercise of this Warrant such number of shares of its
                Common
                Stock as shall be required for issuance and delivery upon exercise
                of the
                Warrants.

          

    


      

          
            
            
            (c)
            FRACTIONAL
                SHARES. No fractional shares or scrip representing fractional shares
                shall
                be issued upon the exercise of this Warrant. With respect to any
                fraction
                of a share called for upon any exercise hereof, the Company shall
                pay to
                the Holder an amount in cash equal to such fraction multiplied by
                the
                current market value of a share, determined as
                follows:

          

    

(1)
       If
      the
      Common Stock (or the common stock of the Company that would be securities
      exchange or admitted to unlisted trading privileges on such exchange or listed
      for trading on the NASDAQ system, the current market value shall be the last
      reported sale price of the Common Stock (or common stock) on such exchange
      or
      system on the last business day prior to the date of exercise of this Warrant
      or
      if no such sale is made on such day, the average closing bid and asked prices
      for such day on such exchange or system; or

(2) 
      If the
      Common Stock is not so listed or admitted to unlisted trading privileges, the
      current market value shall be the mean of the last reported bid and asked prices
      reported by the National Quotation Bureau, Inc. on the last business day prior
      to the date of the exercise of this Warrant; or

(3) 
      If the
      Common Stock is not so listed or admitted to unlisted trading privileges and
      bid
      and asked prices are not so reported, the current market value shall be an
      amount, not less than the book value thereof as at the end of the most recent
      fiscal year of the Company ending prior to the date of the exercise of the
      Warrant, determined in such reasonable manner as may be prescribed by the Board
      of Directors of the Company.


      

          
             
            (d)
                

            EXCHANGE,
                TRANSFER, ASSIGNMENT OR LOSS OF WARRANT. This Warrant is exchangeable,
                without expense, at the option of the Holder, upon presentation and
                surrender hereof to the Company for other warrants of different
                denominations entitling the holder thereof to purchase in the aggregate
                the same number of shares of Common Stock purchasable hereunder.
                Upon
                surrender of this Warrant to the Company at its principal office
                with the
                Assignment Form annexed hereto duly executed and funds sufficient
                to pay
                any transfer tax, the Company shall, without charge, execute and
                deliver a
                new Warrant in the name of the assignee named in such instrument
                of
                assignment and this Warrant shall promptly be cancelled. This Warrant
                may
                be divided or combined with other warrants which carry the same rights
                upon presentation hereof at the principal office of the Company together
                with a written notice specifying the names and denominations in which
                new
                Warrants are to be issued and signed by the Holder hereof. The term
                "Warrant" as used herein includes any Warrants into which this Warrant
                may
                be divided or exchanged. Upon receipt by the Company of evidence
                satisfactory to it of the loss, theft, destruction or mutilation
                of this
                Warrant, and (in the case of loss, theft or destruction) of reasonably
                satisfactory indemnification, and upon surrender and cancellation
                of this
                Warrant, if mutilated, the Company will execute and deliver a new
                Warrant
                of like tenor and date. Any such new Warrant executed and delivered
                shall
                constitute an additional contractual obligation on the part of the
                Company, whether or not this Warrant so lost, stolen, destroyed,
                or
                mutilated shall be at any time enforceable by
                anyone.

          

    
 

        
2

          
        

        
 

      

          
             
            (e)
                

            RIGHTS
                OF THE HOLDER. The Holder shall not, by virtue hereof, be entitled
                to any
                rights of a shareholder in the Company, either at law or equity,
                and the
                rights of the Holder are limited to those expressed in the Warrant
                and are
                not enforceable against the Company except to the extent set forth
                herein.

          

    


      

          
             
            (f)
                

            ANTI-DILUTION
                PROVISIONS. The Exercise Price in effect at any time and the number
                and
                kind of securities purchasable upon the exercise of the Warrants
                shall be
                subject to adjustment from time to time upon the happening of certain
                events as follows:

          

    


      

          
            
            
            (1)
            In
                case the Company shall (i) declare a dividend or make a distribution
                on
                its outstanding shares of Common Stock in shares of Common Stock,
                (ii)
                subdivide or reclassify its outstanding shares of Common Stock into
                a
                greater number of shares, or (iii) combine or reclassify its outstanding
                shares of Common Stock into a smaller number of shares, the Exercise
                Price
                in effect at the time of the record date for such dividend or distribution
                or of the effective date of such subdivision, combination or
                reclassification shall be adjusted so that the Exercise Price shall
                be
                proportionately increased (as in the case of (iii), above) or decreased
                (as in the case of (i) or (ii), above). Such adjustment shall be
                made
                successively whenever any event listed above shall
                occur.

          

    


      

          
            
            
            (2)
            Whenever
                the Exercise Price payable upon exercise of each Warrant is adjusted
                pursuant to Subsections (1) above, the number of Shares purchasable
                upon
                exercise of this Warrant shall simultaneously be adjusted by multiplying
                the number of Shares initially issuable upon exercise of this Warrant
                by
                the Exercise Price in effect on the date hereof and dividing the
                product
                so obtained by the Exercise Price, as
                adjusted.

          

    


      

          
            
            
            (3)
            No
                adjustment in the Exercise Price shall be required unless such adjustment
                would require an increase or decrease of at least two cents ($0.02)
                in
                such price; provided, however, that any adjustments which by reason
                of
                this Subsection (5) are not required to be made shall be carried
                forward
                and taken into account in and subsequent adjustment required to be
                made
                hereunder. All calculations under this Section (f) shall be made
                to the
                nearest cent or to the nearest one-hundredth of a share, as the case
                may
                be. Anything in this Section (f) to the contrary notwithstanding,
                the
                Company shall be entitled, but shall not be required, to make such
                changes
                in the Exercise Price, in addition to those required by this Section
                (f),
                as it shall determine, in its sole discretion, to be advisable in
                order
                that any dividend or distribution in shares of Common Stock, or any
                subdivision, reclassification or combination of Common Stock, hereafter
                made by the Company shall not result in any Federal income tax liability
                to the holders of Common Stock or securities convertible into Common
                or
                Common Stock (including Warrants).

          

    
 

        
3

          
        

        
 

      

          
            
            
            (4)
            Whenever
                the Exercise Price is adjusted, as herein provided, the Company shall
                promptly but no later than 20 days after any request for such an
                adjustment by the Holder, cause a notice setting forth the adjusted
                Exercise Price and adjusted number of Shares issuable upon exercise
                of
                each Warrant, and, if requested, information describing the transactions
                giving rise to such adjustments, to be mailed to the Holder at his
                last
                address appearing in the Warrant Register, and shall cause a certified
                copy thereof to be mailed to its transfer agent, if any. The Company
                may
                retain a firm of independent certified public accountants selected
                by the
                Board of Directors (who may be the regular accountants employed by
                the
                Company) to make any computation required by this Section (t), and
                a
                certificate signed by such firm shall be conclusive evidence of the
                correctness of such adjustment.

          

    
 

      

          
            
            
            (5)
            In
                the event that at any time, as a result of an adjustment made pursuant
                to
                Subsection (1) above, the Holder of this Warrant thereafter shall
                become
                entitled to receive any shares of the Company, other than Common
                Stock,
                thereafter the number of such other shares so receivable upon exercise
                of
                this Warrant shall be subject to adjustment from time to time in
                a manner
                and on terms as nearly equivalent as practicable to the provisions
                with
                respect to the Common Stock contained in Subsections (1) to (4),
                inclusive
                above.

          

    
 

      

          
            
            
            (6)
            Irrespective
                of any adjustments in the Exercise Price or the number or kind of
                shares
                purchasable upon exercise of this Warrant, Warrants theretofore or
                thereafter issued may continue to express the same price and number
                and
                kind of shares as are stated in the similar Warrants initially issuable
                pursuant to this Agreement.

          

    


      

          
             
            (g)
                

            OFFICER'S
                CERTIFICATE. Whenever the Exercise Price shall be adjusted as required
                by
                the provisions of the foregoing Section, the Company shall forthwith
                file
                in the custody of its Secretary or an Assistant Secretary at its
                principal
                office an officer's certificate showing the adjusted Exercise Price
                determined as herein provided, setting forth in reasonable detail
                the
                facts requiring such adjustment, including a statement of the number
                of
                additional shares of Common Stock, if any, and such other facts as
                shall
                be necessary to show the reason for and the manner of computing such
                adjustment. Each such officer's certificate shall be made available
                at all
                reasonable times for inspection by the Holder or any holder of a
                Warrant
                executed and delivered pursuant to Section (a) and the Company shall,
                forthwith after each such adjustment, mail a copy by certified mail
                of
                such certificate to the Holder or any such
                holder.

          

    


      

          
             
            (h)
                

            NOTICES
                TO WARRANT HOLDERS. So long as this Warrant shall be outstanding,
                (i) if
                the Company shall pay any dividend or make any distribution upon
                the
                Common Stock or (ii) if the Company shall offer to the holders of
                Common
                Stock for subscription or purchase by them any share of any class
                or any
                other rights or (iii) if any capital reorganization of the Company,
                reclassification of the capital stock of the Company, consolidation
                or
                merger of the Company with or into another corporation, sale, lease
                or
                transfer of all or substantially all of the property and assets of
                the
                Company to another corporation, or voluntary or involuntary dissolution,
                liquidation or winding up of the Company shall be effected, then
                in any
                such case, the Company shall cause to be mailed by certified mail
                to the
                Holder, at least fifteen days prior to the date specified in (x)
                or (y)
                below, as the case may be, a notice containing a brief description
                of the
                proposed action and stating the date on which (x) a record is to
                be taken
                for the purpose of such dividend, distribution or rights, or (y)
                such
                reclassification, reorganization, consolidation, merger, conveyance,
                lease, dissolution, liquidation or winding up is to take place and
                the
                date, if any is to be fixed, as of which the holders of Common Stock
                or
                other securities shall receive cash or other property deliverable
                upon
                such reclassification, reorganization, consolidation, merger, conveyance,
                dissolution, liquidation or winding
                up.

          

    
 

        
4

          
        

        
 

      

          
             
            (i)

            RECLASSIFICATION,
                REORGANIZATION OR MERGER. In case of any reclassification, capital
                reorganization or other change of outstanding shares of Common Stock
                of
                the Company, or in case of any consolidation or merger of the Company
                with
                or into another corporation (other than a merger with a subsidiary
                in
                which merger the Company is the continuing corporation and which
                does not
                result in any reclassification, capital reorganization or other change
                of
                outstanding shares of Common Stock of the class issuable upon exercise
                of
                this Warrant) or in case of any sale, lease or conveyance to another
                corporation of the property of the Company as an entirety, the Company
                shall, as a condition precedent to such transaction, cause effective
                provisions to be made so that the Holder shall have the right thereafter
                by exercising this Warrant at any time prior to the expiration of
                the
                Warrant, to purchase the kind and amount of shares of stock and other
                securities and property receivable upon such reclassification, capital
                reorganization and other change, consolidation, merger, sale or conveyance
                by a holder of the number of shares of Common Stock which might have
                been
                purchased upon exercise of this Warrant immediately prior to such
                reclassification, change, consolidation, merger, sale or conveyance.
                Any
                such provision shall include provision for adjustments which shall
                be as
                nearly equivalent as may be practicable to the adjustments provided
                for in
                this Warrant. The foregoing provisions of this Section (i) shall
                similarly
                apply to successive reclassifications, capital reorganizations and
                changes
                of shares of Common Stock and to successive consolidations, mergers,
                sales
                or conveyances. In the event that in connection with any such capital
                reorganization or reclassification, consolidation, merger, sale or
                conveyance, additional shares of Common Stock shall be issued in
                exchange,
                conversion, substitution or payment, in whole or in part, for a security
                of the Company other than Common Stock, any such issue shall be treated
                as
                an issue of Common Stock covered by the provisions of Subsection
                (1) of
                Section (f) hereof.

          

    
 

      

          
             
            (j)

            REGISTRATION
                UNDER THE SECURITIES ACT OF 1933. Until the expiry date of this Warrant,
                the provisions of the Registration Rights Agreement dated as of even
                date
                herewith between the Holder of the Warrants and the Company shall
                apply to
                registration of the Warrant Shares. The Company's agreements with
                respect
                to Warrants or Warrant Shares in such Registration Rights Agreement
                shall
                continue in effect regardless of the exercise and surrender of this
                Warrant.

          

    
 

      

          
             
            (k)

            RESTRICTIVE
                LEGEND. Each Warrant Share, when issued, shall include a legend in
                substantially the following form:

          

    
 
                                       
      THESE SHARES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE
      "ACT") NOR UNDER ANY STATE SECURITIES LAW AND MAY NOT BE PLEDGED, SOLD, ASSIGNED
      OR OTHERWISE TRANSFERRED UNTIL A (1) REGISTRATION STATEMENT UNDER THE ACT AND
      ANY APPLICABLE STATE SECURITIES LAW HAS BECOME EFFECTIVE WITH RESPECT THERETO,
      OR (2) RECEIPT BY THE COMPANY OF AN OPINION OF COUNSEL TO THE COMPANY TO THE
      EFFECT THAT REGISTRATION UNDER THE ACT OR APPLICABLE STATE SECURITIES LAW IS
      NOT
      REQUIRED IN CONNECTION WITH THE PROPOSED TRANSFER.
 

        
5

          
        

        

The
      Company will not, by amendment of its charter or through reorganization,
      consolidation, merger, dissolution, sale of assets or any other voluntary
      action, avoid or seek to avoid the observance or performance of any of the
      terms
      of this Warrant, but will at all times in good faith assist in the carrying
      out
      of all such terms and in the taking of all such action as may be necessary
      or
      appropriate in order to protect the rights of the Holder of this Warrant against
      impairment.
 

      

          
             Dated:
              December 31, 2007
             
             
          

             
             
             
          

             
            SPECTRASCIENCE,
              INC.
          

             
 
             
 
             
 
          

            Attest:

            By:  
            
            
          

             ▇▇▇▇▇
              ▇▇▇▇▇▇▇
            
              ▇▇▇▇▇
              ▇▇▇▇▇▇▇
          

             Title:
              Chairman and CEO
            Title:
              Secretary
          

    
 
PURCHASE
      FORM

Dated
      _____________ 20___

The
      undersigned hereby irrevocably elects to exercise the within Warrant to the
      extent of Purchasing ________ shares of Common Stock and hereby makes payment
      of
      ______________ in payment of the actual exercise price thereof.


        
      
 
INSTRUCTIONS
      FOR REGISTRATION OF STOCK

Name
      

      
    
(Please
      typewrite or print in block letters)

Address
      

      
    
 
Signature
      

      
    


       

        
6

          
        

        
 
ASSIGNMENT
      FORM


FOR
      VALUE
      RECEIVED, _____________________________________ hereby sells, assigns and
      transfers unto

Name
      

      
    
(Please
      typewrite or print in block letters)

Address
      

      
    
the
      right
      to purchase Common Stock represented by this Warrant to the extent of _________
      shares as to which such right is exercisable and does hereby irrevocably
      constitute and appoint ______________ Attorney, to transfer the same on the
      books of the Company with full power of substitution in the
      premises.

Date
      _________, 20___

Signature
      _______________________
 

        
7

          
        

        
 
Void after 5:00 p.m. Central Standard Time, on December 31, 2012 Warrant to Purchase 714,285 Shares of Common Stock. WARRANT TO PURCHASE COMMON STOCK OF SPECTRASCIENCE, INC.

Document Metadata

Document Metadata

Table of Contents

Dated: December 31, 2007

	SPECTRASCIENCE, INC.

Attest:	By:
▇▇▇▇▇ ▇▇▇▇▇▇▇		▇▇▇▇▇ ▇▇▇▇▇▇▇
Title: Chairman and CEO		Title: Secretary