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                                                                     Exhibit 4.3

                                     WARRANT
                                     -------


THE SECURITIES REPRESENTED HEREBY AND THE SECURITIES WHICH MAY BE ACQUIRED UPON
THE EXERCISE OF THIS COMMON STOCK PURCHASE WARRANT HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), AND MAY NOT BE SOLD,
PLEDGED, HYPOTHECATED, DONATED OR OTHERWISE TRANSFERRED (WHETHER OR NOT FOR
CONSIDERATION) BY THE HOLDER WITHOUT AN EFFECTIVE REGISTRATION STATEMENT UNDER
THE ACT OR AN OPINION SATISFACTORY TO THE COMPANY OF COUNSEL SATISFACTORY TO THE
COMPANY TO THE EFFECT THAT ANY SUCH TRANSFER SHALL NOT BE IN VIOLATION OF THE
ACT.

Void after _________, 200__, or                  Right to Purchase ______ Shares
otherwise as provided herein                       of Common Stock, $0.0001 par
                                              value per share, of SpaceDev, Inc.


                                  WARRANT N -__

                                 SPACEDEV, INC.
                          COMMON STOCK PURCHASE WARRANT

         SpaceDev, Inc., a Colorado corporation (the "Company"), for value
received and subject to the terms set forth below and in that certain Note
Purchase Agreement ("Purchase Agreement") and Series A Convertible Note (the
"Note") of even date herewith, hereby grants to ____________________________ and
his registered successors and assigns (the "Holder") the right to purchase from
the Company, at any time or from time to time before 3:00 P.M., California time,
on ___________, 200__, ________ fully paid and non-assessable shares of the
Common Stock, par value $0.0001 per share, of the Company, at the Exercise Price
(as defined below). The Exercise Price and the number and character of such
shares of Common Stock purchasable pursuant to the rights granted under this
Warrant are subject to adjustment as provided herein.

         This Warrant is subject to the following provisions:

         1. DEFINITIONS. As used herein the following terms, unless the context
otherwise requires, have the following respective meanings:

         (a) "Common Stock" means the Company's $0.0001 par value common stock.

         (b) "Exercise Price" means the Conversion Price, as that term is
         defined in Section 2.2 of the Note.

         (c) "Issue Date" means __________, 200__.

         (d) "Other Securities" means any stock (other than Common Stock) and
         other securities of the Company or any other Person (corporate or
         other) which the Holder of this Warrant at any time shall be entitled
         to receive, or shall have received, upon the exercise of this Warrant,
         in lieu of or in addition to Common Stock, or which at any time shall
         be issuable or shall have been issued in exchange for or in replacement
         of Common Stock.

         (e) "Person" means, without limitation, an individual, a partnership, a
         corporation, a trust, a joint venture, an unincorporated organization,
         or a government or any department or agency thereof.

         (f) "This Warrant" means, collectively, this Warrant and all other
         stock purchase warrants issued in exchange herefor or replacement
         hereof.

         2. EXERCISE OF WARRANT.

         2.1 EXERCISE PERIOD. The Holder may exercise this Warrant, in whole or
in part (but not as to a fractional share of Common Stock), at any time and from
time to time prior to 3:00 P.M. California time on ____________, 200__.

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         2.2      EXERCISE PROCEDURE.

         (a) This Warrant will be deemed to have been exercised at such time as
         the Company has received all of the following items (the "Exercise
         Date"):

                  (i) a completed Notice of Exercise in the form attached hereto
                  as Exhibit A and such Purchase Agreement as the Company shall
                  require, executed by the Holder exercising all or part of the
                  purchase rights represented by this Warrant (the "Purchaser");

                  (ii) this Warrant;

                  (iii) if this Warrant is not registered in the name of the
                  Purchaser, an Assignment or Assignments in the form set forth
                  in Exhibit B hereto, evidencing the assignment of this Warrant
                  to the Purchaser together with any documentation required
                  pursuant to Section 6(a) hereof; and

                  (iv) a check payable to the order of the Company in an amount
                  equal to the product of the Exercise Price multiplied by the
                  number of shares of Common Stock being purchased upon such
                  exercise;

         (b) As soon as practicable after the exercise of this Warrant in full
         or in part, and in any event within ten (10) days after the Exercise
         Date, the Company at its expense will cause to be issued in the name of
         and delivered to the Holder hereof, or as the Holder (upon payment by
         the Holder of any applicable transfer taxes) may direct, a certificate
         or certificates for the number of fully paid and non-assessable shares
         of Common Stock (or Other Securities) to which the Holder shall be
         entitled upon such exercise, together with any other stock or other
         securities and property (including cash, where applicable) to which the
         Holder is entitled upon exercise.

         (c) Unless this Warrant has expired or all of the purchase rights
         represented hereby have been exercised, the Company at its expense
         will, within ten (10) days after the Exercise Date, issue and deliver
         to or upon the order of the Holder hereof a new Warrant or Warrants of
         like tenor, in the name of the Holder calling in the aggregate on the
         face or faces thereof for the number of shares of Common Stock
         remaining issuable under this Warrant.

         (d) The Common Stock (or Other Securities) issuable upon the exercise
         of this Warrant will be deemed to have been issued to the Purchaser on
         the Exercise Date, and the Purchaser will be deemed for all purposes to
         have become the record holder of such Common Stock (or Other
         Securities) on the Exercise Date.

         (e) The issuance of certificates for shares of Common Stock (or Other
         Securities) upon exercise of this Warrant will be made without charge
         to the Holder for any issuance tax in respect thereof or any other cost
         incurred by the Company in connection with such exercise and the
         related issuance of Shares of Common Stock (or Other Securities).

         2.3 FRACTIONAL SHARES. If a fractional share of Common Stock would, but
for the provisions of Section 2.1 hereof, be issuable upon exercise of the
rights represented by this Warrant, the Company will, within ten (10) days after
the Exercise Date, deliver to the Purchaser a check payable to the Purchaser in
lieu of such fractional share, in an amount equal to the Market Price of such
fractional share as of the close of business on the Exercise Date.

         3. ADJUSTMENTS; CANCELLATION.

         3.1 STOCK SPLITS, ETC. If the Company shall at any time after the Issue
Date subdivide its outstanding Common Stock or Other Securities, by split-up or
otherwise, or combine its outstanding Common Stock or Other Securities, or issue
additional shares of its capital stock in payment of a stock dividend in respect
of its Common Stock or Other Securities, the number of shares issuable on the
exercise of the unexercised portion of this Warrant shall forthwith be
proportionately increased in the case of such a subdivision or stock dividend,
or proportionately decreased in the case of such combination, and the Exercise
Price then applicable to shares covered by the unexercised portion of this
Warrant shall forthwith be proportionately decreased in the case of such a
subdivision or stock dividend, or proportionately increased in the case of such
combination.


                                       2
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         3.2 RECLASSIFICATION, REORGANIZATION, ETC. In case of any
reclassification, capital reorganization or change of the outstanding Common
Stock or Other Securities (other than as a result of a subdivision, combination
or stock dividend) or any exchange or conversion of the Common Stock for or into
securities of another entity, or in case of the consolidation or merger of the
Company with or into any other Person or in case of any sale or conveyance of
all or substantially all of the assets of the Company (any of the foregoing
being a "Reorganization Transaction"), then, as a condition of such
Reorganization Transaction, lawful provision shall be made so that the Holder
shall have the right at any time prior to the expiration of this Warrant to
purchase, at a total price not to exceed that payable upon the exercise of the
unexercised portion of this Warrant, the kind and amount of shares of stock and
other securities and property receivable upon such Reorganization Transaction by
a holder of the number of shares of Common Stock or Other Securities of the
Company as to which this Warrant was exercisable immediately prior to such
Reorganization Transaction, and in any such case appropriate provision shall be
made with respect to the rights and interests of the Holder to the end that the
provisions hereof (including, without limitation, provisions for the adjustment
of the Exercise Price and of the number of shares purchasable upon exercise of
this Warrant) shall thereafter be applicable in relation to any shares of stock,
and other securities and property, thereafter deliverable upon exercise hereof.

         3.3 DIVIDENDS. In case the Company shall, at any time or from time to
time after the Issue Date, pay any dividend or make any other distribution upon
its Common Stock (or Other Securities) payable in cash, property or securities
of a corporation other than the Company, then forthwith upon the payment of such
dividend, or the making of such other distribution, as the case may be, the
Exercise Price then in effect shall be reduced by the amount of such dividend or
other distribution in respect of each outstanding share of Common Stock (or
Other Securities). The Board of Directors of the Company shall determine the
fair value of any dividend or other distribution made upon Common Stock of the
Company payable in property or securities of a corporation other than the
Company.

         3.4 CERTIFICATE OF ADJUSTMENT. Whenever the Exercise Price or the
number of shares issuable hereunder is adjusted, as herein provided, the Company
shall promptly deliver to the Holder a certificate of the Treasurer of the
Company, which certificate shall state (i) the Exercise Price and the number of
shares of Common Stock (or Other Securities) issuable hereunder after such
adjustment, (ii) the facts requiring such adjustment, and (iii) the method of
calculation for such adjustment and increase or decrease.

         3.5 SMALL ADJUSTMENTS. No adjustment in the Exercise Price shall be
required unless such adjustment would require an increase or decrease in the
Exercise Price of at least one percent; provided, however, that any adjustments
which by reason of this Section 3.5 are not required to be made immediately
shall be carried forward and taken into account at the time of exercise of this
Warrant or any subsequent adjustment in the Exercise Price which, singly or in
combination with any adjustment carried forward, is required to be made under
Sections 3.1, 3.2 or 3.3.

         4. IMPAIRMENT. The Company will not, by amendment of its Articles of
Incorporation or By-Laws or through any reorganization, transfer of assets,
consolidation, merger, 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 Warrant, but will at all times in good faith assist in the
carrying out of all such terms and in the taking of all action as may be
necessary or appropriate in order to protect the rights of the Holder against
impairment. Without limiting the generality of the foregoing, the Company will
take all such action 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 (or Other Securities) upon the exercise of this Warrant.

         5. RESERVATION OF STOCK, ETC., ISSUABLE ON EXERCISE OF WARRANT. The
Company will at all times reserve and keep available, solely for issuance and
delivery upon the exercise of this Warrant, all shares of Common Stock (or Other
Securities) from time to time issuable upon the exercise of this Warrant.

         6. DISPOSITION OF THIS WARRANT, COMMON STOCK, ETC.

         (a) The Holder and any proposed transferee hereof or of the Common
         Stock (or Other Securities) with respect to which this Warrant may be
         exercisable, by their acceptance hereof, hereby understand and agree
         that this Warrant and the Common Stock (or Other Securities) with
         respect to which this Warrant may be exercisable have not been
         registered under the Securities Act of 1933, as amended (the "Act"),
         and may not be sold, pledged, hypothecated, donated, or otherwise
         transferred (whether or not for consideration) without an effective
         registration statement under the Act or an opinion satisfactory to the
         Company of counsel satisfactory to the Company and/or submission to the
         Company of such other evidence as may be satisfactory to counsel to the
         Company, in each such case, to the effect that any such transfer shall
         not be in violation of the Act. It shall be a condition to the transfer
         of this Warrant that any transferee hereof deliver to the Company its
         written agreement to accept and be bound by all of the terms and
         conditions of this Warrant.

                                       3
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         (b) The stock certificates of the Company that will evidence the shares
         of Common Stock (or Other Securities) with respect to which this
         Warrant may be exercisable will be imprinted with a conspicuous legend
         in substantially the following form:

         "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
         REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"),
         AND MAY NOT BE SOLD, PLEDGED, HYPOTHECATED, DONATED OR OTHERWISE
         TRANSFERRED (WHETHER OR NOT FOR CONSIDERATION) BY THE HOLDER WITHOUT AN
         EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT OR AN OPINION
         SATISFACTORY TO THE COMPANY OF COUNSEL SATISFACTORY TO THE COMPANY
         AND/OR SUBMISSION TO THE COMPANY OF SUCH OTHER EVIDENCE AS MAY BE
         SATISFACTORY TO COUNSEL TO THE COMPANY, IN EACH CASE, TO THE EFFECT
         THAT ANY SUCH TRANSFER SHALL NOT BE IN VIOLATION OF THE ACT."

         provided, however, that, if the shares of Common Stock (or Other
         Securities) with respect to which this Warrant has been exercised are
         registered in accordance with the provisions of the Act, any stock
         certificates of the Company issued in connection herewith and bearing
         the foregoing legend will, upon written request of the Holder, be
         replaced with a certificate(s) not bearing the foregoing legend.

         7. RIGHTS AND OBLIGATIONS OF HOLDER. The Holder shall not, by virtue
hereof, be entitled to any voting rights or other rights as a stockholder of the
Company. No provision of this Warrant, in the absence of affirmative actions by
the Holder to purchase Common Stock (or Other Securities) of the Company by
exercising this Warrant, and no enumeration in this Warrant of the rights or
privileges of the Holder, will give rise to any liability of the Holder for the
Exercise Price of Common Stock (or Other Securities) acquirable by exercise
hereof or as a stockholder of the Company.

         8. TRANSFER OF WARRANTS. Subject to compliance with the restrictions on
transfer applicable to this Warrant referred to in Section 6 hereof, this
Warrant and all rights hereunder are transferable, in whole or in part, without
charge to the registered Holder, upon surrender of this Warrant with a properly
executed Assignment (in substantially the form attached hereto as Exhibit B), to
the Company, and the Company at its expense will issue and deliver to or upon
the order of the Holder a new Warrant or Warrants in such denomination or
denominations as may be requested, but otherwise of like tenor, in the name of
the Holder or as the Holder (upon payment of any applicable transfer taxes) may
direct.

         9. REPLACEMENT OF WARRANTS. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of any
Warrant and, in the case of any such loss, theft or destruction, upon delivery
of an indemnity agreement reasonably satisfactory in form and amount to the
Company or, in the case of any such mutilation, upon surrender and cancellation
of such Warrant, the Company at its expense will execute and deliver, in lieu
thereof, a new Warrant of like tenor.

         10. COMPANY RECORDS. Until this Warrant is transferred on the books of
the Company, the Company may treat the registered Holder hereof as the absolute
owner hereof for all purposes, notwithstanding any notice to the contrary.

         11. MISCELLANEOUS.

         11.1 NOTICES. All notices and other communications from the Company to
the Holder shall be mailed by first class mail, postage prepaid, to such address
as may have been furnished to the Company in writing by the Holder, or, until an
address is so furnished, to and at the address of the last previous Holder who
has so furnished an address to the Company. All communications from the Holder
to the Company shall be mailed by first class mail, postage prepaid, to the
Company at 13855 Stowe Drive, Poway, California 92064, or such other address as
may have been furnished to the Holder in writing by the Company.

         11.2 AMENDMENT AND WAIVER. Except as otherwise provided herein, this
Warrant and any term hereof may be amended, waived, discharged or terminated
only by an instrument in writing signed by the party against which enforcement
of such amendment, waiver, discharge or termination is sought.

                                       4
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         11.3 GOVERNING LAW; DESCRIPTIVE HEADINGS. This Warrant shall be
construed and enforced in accordance with and governed by the internal laws of
the State of California. The headings in this Warrant are for purposes of
reference only, and shall not limit or otherwise affect any of the terms hereof.


Dated:  __________, 200__                     SPACEDEV, INC.



                                              By:_______________________________
                                                 James W. Benson
                                                 Chief Executive Officer

                                       5
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                                    EXHIBIT A

                               NOTICE OF EXERCISE


SpaceDev, Inc.
13855 Stowe Drive                      Date of Exercise:___________
Poway, CA 92064

To Whom It May Concern:

This constitutes notice under the SpaceDev, Inc. (the "Company") common stock
purchase warrant granted to me on ______________ (the "Warrant") that I elect to
purchase the number of shares for the price set forth below:


         Number of shares as to
         which warrant is exercised:                 _______________________

         Certificates to be issued
         in name of:                                 _______________________

         Social Security Number:                     _______________________

         Total exercise price:                       _______________________

         Cash payment delivered herewith:            _______________________

I represent that I am purchasing the shares for investment purposes only, for my
own account and not with the intent to resell or otherwise transfer or
distribute the shares to or on behalf of any third party.

By this exercise, I agree to provide such additional documents as you may
require pursuant to the terms of the Warrant.



                                                  Sincerely,


                                                  ------------------------------
                                                  Signature


                                                  ------------------------------
                                                  Print Name

<PAGE>


                                    EXHIBIT B

                                   ASSIGNMENT

                  [To be signed only upon exercise of Warrant]


         For value received, the undersigned hereby sells, assigns and transfers
all of the rights of the undersigned under the within Warrant with respect to
the number of shares of the Common Stock (or Other Securities) covered thereby
set forth below, unto:

Name of Assignee              Address                       No. of Shares


---------------------------   ----------------------------  ------------------

                              ----------------------------


Dated:                        Signature:  _____________________________________
                                          (Signature must conform in all
                                          respects to name of Holder as
                                          specified on the face of the Warrant).


                              Address:  ________________________________________

                                        ________________________________________