VOTING AGREEMENT
 
     This VOTING AGREEMENT (this “Agreement”), is made and entered into as of
________________, 2008, by and between Sierra Nevada Corporation, a Nevada
corporation (“Buyer”), and the undersigned securityholder (“Stockholder”) of
SpaceDev, Inc., a Delaware corporation (the “Company”).
 
RECITALS
 
     A.                       Concurrently with or shortly following the
execution of this Agreement, Buyer, SDV Acquisition Corp., a Delaware
corporation and a wholly owned subsidiary of Buyer (“Merger Sub”), and the
Company are entering into an Agreement and Plan of Merger (the “Merger
Agreement”), pursuant to which Merger Sub will be merged with and into the
Company (the “Merger”). Capitalized terms used but not defined herein shall have
the meanings given to them in the Merger Agreement.
 
     B.                       As of the date hereof, Stockholder is the direct,
indirect and/or beneficial owner of certain shares of Company capital stock as
is indicated on the signature pages to this Agreement.
 
     C.                       As a material inducement to enter into the Merger
Agreement, Buyer desires Stockholder to agree, and Stockholder is willing to
agree, to vote the Shares (as defined in Section 1.1 below), and such other
shares of capital stock of the Company over which Stockholder has voting power,
so as to facilitate consummation of the Merger.
 
                In consideration of the foregoing and the representations,
warranties, covenants and agreements set forth in this Agreement, the parties
agree as follows:
 
     1.            Voting of Shares.
 
          1.1                      Shares. The term “Shares” shall mean all
issued and outstanding shares of Company Common Stock and Preferred Stock owned
of record and beneficially owned (as defined in Rule 13d-3 under the Exchange
Act of 1934, as amended ( “Rule 13d-3”)) by Stockholder or over which
Stockholder exercises sole voting power, in each case, as of the date of this
Agreement. Stockholder agrees that any shares of capital stock of the Company
that Stockholder purchases or with respect to which Stockholder otherwise
acquires beneficial ownership of after the date of this Agreement and prior to
the termination of this Agreement pursuant to Section 5 below shall be subject
to the terms and conditions of this Agreement to the same extent as if they
constituted Shares as of the date hereof.
 
           1.2                      Agreement to Vote Shares. Stockholder hereby
covenants and agrees that during the period commencing on the date hereof and
continuing until this Agreement terminates pursuant to Section 5 hereof, at any
meeting (whether annual or special and whether or not an adjourned or postponed
meeting) of the stockholders of the Company, however called, and in any action
by written consent of the stockholders of the Company, Stockholder shall appear
at the meeting or otherwise cause any and all Shares to be counted as present
thereat for purposes of establishing a quorum and vote (or cause to be voted)
any and all Shares: (i) in favor of the approval of the Merger and adoption of
the Merger Agreement; (ii) against any Acquisition Proposal or Superior
Proposal; and (iii) against any proposal or transaction which could prevent or
delay the consummation of the Merger or the Merger Agreement. Stockholder
further agrees not to enter into any agreement or understanding with any person
or entity the effect of which would be inconsistent with or violative of any
provision contained in this Section 1.2. Notwithstanding anything to the
contrary contained herein, nothing in this Agreement shall be construed to limit
or restrict Stockholder from acting in Stockholder’s capacity as a director or
officer of the Company or voting in Stockholder’s sole discretion on any matter
other than those matters referred to in the first sentence of this Section 1.2.
 
 
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          1.3                      Irrevocable Proxy. Concurrently with the
execution of this Agreement, Stockholder agrees to deliver to Buyer a proxy in
the form attached hereto as Exhibit A (the “Proxy”), which shall be irrevocable,
with respect to the Shares, subject to the other terms of this Agreement.
 
          1.4                      Adjustments Upon Changes in Capitalization.
In the event of any change in the number of issued and outstanding shares of
Company Common Stock by reason of any stock split, reverse split, stock dividend
(including any dividend or distribution of securities convertible into Company
Common Stock), combination, reorganization, recapitalization or other like
change, conversion or exchange of shares, or any other change in the corporate
or capital structure of the Company, the term “Shares” shall be deemed to refer
to and include the Shares as well as all such stock dividends and distributions
and any shares into which or for which any or all of the Shares may be changed
or exchanged.
 
     2.            Transfer and Other Restrictions. Stockholder represents,
covenants and agrees that, except for the proxy granted in Section 1.3 hereof
and as contemplated by this Agreement: (i) Stockholder shall not, directly or
indirectly, during the period commencing on the date hereof and continuing until
this Agreement terminates pursuant to Section 5 hereof, offer for sale or agree
to sell, transfer, tender, assign, pledge, hypothecate or otherwise dispose of
or enter into any contract, option or other arrangement or understanding with
respect to, or consent to, the offer for sale, sale, transfer, tender, pledge,
hypothecation, encumbrance, assignment or other disposition of, or create any
Encumbrance of any nature whatsoever with respect to, any or all of the Shares
or any interest therein; (ii) Stockholder shall not grant any proxy or power of
attorney, or deposit any Shares into a voting trust or enter into a voting
agreement or other arrangement, with respect to the voting of Shares (each a
“Voting Proxy”) except as provided by this Agreement; and (iii) Stockholder has
not granted, entered into or otherwise created any Voting Proxy which is
currently (or which will hereafter become) effective, and if any Voting Proxy
has been created, such Voting Proxy is hereby revoked. Notwithstanding the
foregoing, Stockholder may transfer or otherwise dispose of any Shares (A) in
open market resale transactions (e.g. in a transaction in which there have been
no discussions, agreements or understandings between the seller and the buyer or
their respective agents or representatives and in connection with which no
solicitation of buyers or offers to buy has occurred) with respect to resales of
any shares of Company Common Stock, and (B) as a bona fide gift or gifts,
provided that it shall be a condition to such transfer that each donee thereof
executes and delivers to Buyer (1) an agreement with Buyer in the form of this
Agreement and (2) an irrevocable proxy in the form attached hereto as Exhibit A,
in each case with respect to any and all Shares so transferred, and (C) to the
Company.
 
     3.            Representations and Warranties of Stockholder. Stockholder
represents and warrants to Buyer that:
 
          3.1                      Authority; Validity. Stockholder has all
requisite capacity, power and authority to enter into this Agreement and to
consummate the transactions contemplated hereby. The execution and delivery of
this Agreement by Stockholder and the consummation by Stockholder of the
transactions contemplated hereby have been duly and validly authorized by all
necessary action on the part of Stockholder. This Agreement has been duly
executed and delivered by Stockholder. If this Agreement is being executed in a
representative or fiduciary capacity with respect to Stockholder, the person
signing this Agreement has full power and authority to enter into and perform
this Agreement.
 
          3.2                      Non-Contravention. The execution, delivery
and performance of this Agreement does not, and the consummation of the
transactions contemplated hereby and compliance with the provisions hereof will
not, contravene, conflict with, or result in any violation of, breach of or
default by (with or without notice or lapse of time, or both) Stockholder under,
or give rise to a right of termination, cancellation or acceleration of any
obligation under, or result in the creation of any Encumbrance upon any of the
properties or assets of Stockholder under, any provision of (i) any loan or
credit agreement, note, bond, mortgage, indenture, lease or other agreement,
instrument, permit, concession, franchise or license applicable to Stockholder
or (ii) any judgment, order, decree, statute, law, ordinance, injunction, rule
or regulation applicable to Stockholder or any of Stockholder’s properties or
assets, other than any such conflicts, violations, defaults, rights, or
Encumbrances that, individually or in the aggregate, would not impair the
ability of Stockholder to perform Stockholder’s obligations hereunder or
prevent, limit or restrict in any respect the consummation of any of the
transactions contemplated hereby. There is no beneficiary or holder of a voting
trust certificate or other interest of any trust of which Stockholder is settlor
or trustee or any other person or entity, including any Governmental Entity,
whose consent, approval, order or authorization is required by or with respect
to Stockholder for the execution, delivery and performance of this Agreement by
Stockholder or the consummation by Stockholder of the transactions contemplated
hereby.
 
 
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          3.3                      Litigation. There is no action pending, or to
the knowledge of Stockholder, threatened with respect to his ownership of the
Shares, nor is there any judgment, decree, injunction or order of any applicable
Governmental Entity or arbitrator outstanding which would prevent the carrying
out by Stockholder of his obligations under this Agreement or any of the
transactions contemplated hereby, declare unlawful the transactions contemplated
hereby or cause such transactions to be rescinded.
 
          3.4                      Title. Stockholder is the beneficial owner
(as defined in Rule 13d-3) of the Shares of indicated on the signature pages
hereto, which, on and as of the date hereof, are free and clear of any
Encumbrances that, individually or in the aggregate, would impair the ability of
Stockholder to perform Stockholder’s obligations hereunder or prevent, limit or
restrict in any respect the consummation of any of the transactions contemplated
hereby. The number of Shares set forth on the signature pages hereto are the
only Shares owned of record or beneficially owned (as defined in Rule 13d-3) by
Stockholder or over which Stockholder exercises sole voting power and, except as
set forth on such signature pages, Stockholder holds no options or warrants to
purchase or rights to subscribe for or otherwise acquire any securities of the
Company and has no other interest in or voting rights with respect to any
securities of the Company.
 
          3.5                      Power. Stockholder has sole voting power and
sole power to issue instructions with respect to the matters set forth in
Section 1 and Section 2 hereof and sole power to agree to all of the matters set
forth in this Agreement, in each case with respect to all of the Shares, with no
limitations, qualifications or restrictions on such rights.
 
     4.            Representations and Warranties of Buyer. Buyer represents and
warrants to Stockholder that:
 
          4.1                      Authority; Validity. Buyer has all requisite
capacity, power and authority to enter into this Agreement and to consummate the
transactions contemplated hereby. The execution and delivery of this Agreement
by Buyer and the consummation by Buyer of the transactions contemplated hereby
have been duly and validly authorized by all necessary action on the part of
Buyer. This Agreement has been duly executed and delivered by Buyer. If this
Agreement is being executed in a representative or fiduciary capacity with
respect to Buyer, the person signing this Agreement has full power and authority
to enter into and perform this Agreement.
 
          4.2                       Non-Contravention. The execution, delivery
and performance of this Agreement does not, and the consummation of the
transactions contemplated hereby and compliance with the provisions hereof will
not, (a) require Buyer to obtain the consent or approval or, or make any filing
with or notification to, any governmental or regulatory authority, domestic or
foreign, (b) require the consent or approval of any other person pursuant to any
agreement, obligation or instrument binding on Buyer or its properties and
assets, (c) conflict with or violate any organizational document or law, rule
regulation, order, judgment or decree applicable to Buyer or pursuant to which
any of its or its subsidiaries’ respective assets are bound or (d) violate any
other material agreement to which Buyer or any of its subsidiaries is a party.
 
 
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     5.            Effectiveness; Termination; No Survival. This Agreement shall
become effective upon its execution by Stockholder and Buyer or upon the
execution of the Merger Agreement by all parties thereto, whichever is later.
This Agreement may be terminated at any time by mutual written consent of
Stockholder and Buyer. This Agreement, and the obligations of Stockholder
hereunder, including, without limitation, Stockholder’s obligations under
Section 1 and Section 2 above, shall terminate, without any action by the
parties hereto, upon the earlier to occur of the following: (i) such date and
time as the Merger shall become effective in accordance with the terms and
provisions of the Merger Agreement; and (ii) such date and time as the Merger
Agreement shall have been validly terminated pursuant to Article VIII thereof.
 
     6.            Further Assurances. Subject to the terms of this Agreement,
from time to time, Stockholder shall execute and deliver such additional
documents and use commercially reasonable efforts to take, or cause to be taken,
all such further actions, and to do or cause to be done, all things reasonably
necessary, proper or advisable under applicable laws and regulations to
consummate and make effective the transactions contemplated by this Agreement.
 
     7.            Miscellaneous.
 
          7.1                      Severability. If any term, provision,
covenant or restriction of this Agreement is held by a court of competent
jurisdiction to be invalid, void or unenforceable, the remainder of the terms,
provisions, covenants and restrictions of this Agreement shall remain in full
force and effect and shall in no way be affected, impaired or invalidated.
 
          7.2                      Binding Effect and Assignment. This Agreement
and all of the provisions hereof shall be binding upon and inure to the benefit
of the parties hereto and their respective successors and permitted assigns,
but, except as otherwise specifically provided herein, neither this Agreement
nor any of the rights, interests or obligations of the parties hereto may be
assigned by either of the parties without the prior written consent of the
other; provided that the consent of Stockholder shall not be required for an
assignment by Buyer of any or all of its rights (but not obligations) hereunder
to any one or more of its lenders. Any purported assignment in violation of this
Section 7.2 shall be void.
 
          7.3                      Amendments and Modification. This Agreement
may not be modified, amended, altered or supplemented except upon the execution
and delivery of a written agreement executed by the parties hereto.
 
          7.4                      Specific Performance; Injunctive Relief;
Attorneys Fees. The parties hereto acknowledge that Buyer will be irreparably
harmed and that there will be no adequate remedy at law for a violation of any
of the covenants or agreements of Stockholder set forth herein. Therefore, it is
agreed that, in addition to any other remedies that may be available to Buyer
upon any such violation, Buyer shall have the right to enforce such covenants
and agreements by specific performance, injunctive relief or by any other means
available to Buyer at law or in equity and Stockholder hereby irrevocably and
unconditionally waives any objection to Buyer seeking so to enforce such
covenants and agreements by specific performance, injunctive relief and other
means. If any action, suit or other proceeding (whether at law, in equity or
otherwise) is instituted concerning or arising out of this Agreement or any
transaction contemplated hereunder, the prevailing party shall recover, in
addition to any other remedy granted to such party therein, all such party’s
costs and attorneys fees incurred in connection with the prosecution or defense
of such action, suit or other proceeding.
 
          7.5                      Notices. All notices and other communications
hereunder shall be in writing and shall be deemed given upon delivery either
personally or by commercial delivery service, or sent via facsimile (receipt
confirmed) to the parties at the addresses or facsimile numbers set forth on the
signature page hereof (or at such other address or facsimile numbers for a party
as shall be specified by like notice).
 
 
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          7.6                      Governing Law; Submission to Jurisdiction.
This Agreement shall be governed by and construed in accordance with the laws of
the State of Delaware, regardless of the laws that might otherwise govern under
applicable principles of conflicts of law thereof. The parties hereby
irrevocably and unconditionally consent to submit to the exclusive jurisdiction
of the courts of the United States of America located in the State of Delaware
(or, if such courts lack jurisdiction, the appropriate Delaware state courts)
for any actions, suits or proceedings arising out of or relating to this
Agreement (and the parties agree not to commence any action, suit or proceeding
relating thereto except in such courts), and further agree that service of any
process, summons, notice or document by U.S. certified mail shall be effective
service of process for any action, suit or proceeding brought against the
parties in any such court. The parties hereby irrevocably and unconditionally
waive any objection to the laying of venue of any action, suit or proceeding
arising out of this Agreement in the courts of the United States of America
located in the State of Delaware (or, if such courts lack jurisdiction, the
appropriate Delaware state courts) and hereby further irrevocably and
unconditionally waive and agree not to plead or claim in any such court that any
such action, suit or proceeding brought in any such court has been brought in an
inconvenient forum.
 
          7.7                       Entire Agreement. The Merger Agreement, this
Agreement and the Proxy granted hereunder constitute and contain the entire
agreement and understanding of the parties with respect to the subject matter
hereof and supersede any and all prior negotiations, correspondence, agreements,
understandings, duties or obligations between the parties respecting the subject
matter hereof.
 
          7.8                      Counterparts. This Agreement may be executed
in counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.
 
          7.9                      Captions. The captions to sections of this
Agreement have been inserted only for identification and reference purposes and
shall not be used to construe or interpret this Agreement.
 
          7.10                      Stockholder Capacity. Notwithstanding
anything herein to the contrary, Stockholder makes no agreement or understanding
herein in his capacity as a director or officer of the Company or any subsidiary
of the Company, and the agreements set forth herein shall in no way restrict
Stockholder in the exercise of his fiduciary duties as a director or officer of
the Company or any subsidiary of the Company or limit or affect any actions
taken by Stockholder solely in his capacity as an officer or director of the
Company or any subsidiary of the Company. Stockholder has executed this
Agreement solely in his capacity as the record and/or beneficial holder of
Shares.
 
          7.11                      No Ownership Interest. Nothing contained in
this Agreement shall be deemed to vest in Buyer or Merger Sub any direct or
indirect ownership or incidence of ownership of or with respect to the Shares.
All rights, ownership and economic benefits of and relating to such Shares shall
remain vested in and belong to Stockholder or his affiliates, and Buyer and
Merger Sub shall have no authority to direct Stockholder in the voting or
disposition of any Shares, except as otherwise provided herein.
 

 
[Signature Pages Follow]
 
 
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     IN WITNESS WHEREOF, the parties hereto have caused this Voting Agreement to
be executed as of the date first above written.
 
 

 

 SIERRA NEVADA CORPORATION    STOCKHOLDER            (Print or Type Name of
Stockholder)         By:    By:         Title:    Title:    
 (If Applicable)
 Address:    Address:  444 Salomon Circle      Sparks, NV  89436     
 Attn:  Staff Counsel             Fax:  (775) 331-0370        Fax:          
 Outstanding Shares of Company Common Stock Beneficially Owned by Stockholder:  
               Outstanding Shares of Company Preferred Stock Beneficially Owned
by Stockholder:                  
Options, Warrants or Rights to purchase Company Common Stock Beneficially Owned
by Stockholder:
                       

 
                                                                                                

 
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EXHIBIT A
 
IRREVOCABLE PROXY
 
     The undersigned stockholder (“Stockholder”) of SpaceDev, Inc., a Delaware
corporation (the “Company”), hereby irrevocably appoints and constitutes the
members of the Board of Directors of Sierra Nevada Corporation, a Nevada
corporation (“Buyer”), and each such Board member (collectively, the
“Proxyholders”), the agents, attorneys-in-fact and proxies of the undersigned,
with full power of substitution and resubstitution, to the full extent of the
undersigned’s rights with respect to all shares of capital stock of the Company
now or hereafter owned of record or beneficially by the undersigned (the
“Shares”), including, without limitation, those listed on the signature page of
that certain Voting Agreement of even date herewith between Buyer and
Stockholder (the “Voting Agreement”), and any and all other shares or securities
issued or issuable in respect thereof on or after the date hereof and prior to
the date this proxy terminates, to vote the Shares as follows: the Proxyholders
named above are empowered at any time prior to termination of this proxy to
exercise all voting and other rights (including, without limitation, the power
to execute and deliver written consents with respect to the Shares) of the
undersigned at every annual, special or adjourned meeting of the Company’s
stockholders, and in every written consent in lieu of any such meeting, or
otherwise, (i) in favor of the approval of the merger of SDV Acquisition Corp.,
a Delaware corporation and a wholly owned subsidiary of Buyer (“Merger Sub”),
with and into the Company pursuant to that certain Agreement and Plan of Merger
by and among Buyer, Merger Sub and the Company (the “Merger Agreement”), and in
favor of adoption of the Merger Agreement; (ii) against any Acquisition Proposal
or Superior Proposal (each as defined in the Merger Agreement); and
(iii) against any proposal or transaction which could prevent or delay the
consummation of the Merger or the Merger Agreement.
 
     The Proxyholders may not exercise this proxy on any other matter.
Stockholder may vote the Shares on all matters other than those set forth in the
immediately preceding paragraph. The proxy granted by Stockholder to the
Proxyholders hereby is granted as of the date of this Irrevocable Proxy in order
to secure the obligations of Stockholder set forth in Section 1.2 of the Voting
Agreement, and is irrevocable in accordance with subdivision (e) of Section 212
of the Delaware General Corporation Law.
 
     This proxy will terminate upon the termination of the Voting Agreement in
accordance with its terms. Upon the execution hereof, all prior proxies given by
the undersigned with respect to the Shares and any and all other shares or
securities issued or issuable in respect thereof on or after the date hereof are
hereby revoked and no subsequent proxies will be given until such time as this
proxy shall be terminated in accordance with its terms. Any obligation of the
undersigned hereunder shall be binding upon the successors and assigns of the
undersigned. The undersigned Stockholder authorizes the Proxyholders to file
this proxy and any substitution or revocation of substitution with the Secretary
of the Company and with any Inspector of Elections at any meeting of the
stockholders of the Company.
 
          This proxy is irrevocable and shall survive the insolvency,
incapacity, death, liquidation or dissolution of the undersigned.
 

  Dated:    
 
 
       (Print or Type Name of Stockholder)      
 
 
       Signature      
 
 
       Title (if applicable)

      
 
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