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                                                                    Exhibit 10.3

                        DYNAVAX TECHNOLOGIES CORPORATION

                        2004 EMPLOYEE STOCK PURCHASE PLAN

      The following constitute the provisions of the 2004 Employee Stock
Purchase Plan of Dynavax Technologies Corporation.

      1. Purpose. The purpose of the Plan is to provide Employees of the Company
and its Designated Parents or Subsidiaries with an opportunity to purchase
Common Stock of the Company through accumulated payroll deductions. It is the
intention of the Company to have the Plan qualify as an "Employee Stock Purchase
Plan" under Section 423 of the Code and the applicable regulations thereunder.
The provisions of the Plan, accordingly, shall be construed so as to extend and
limit participation in a manner consistent with the requirements of that Section
423 of the Code.

      2. Definitions. As used herein, the following definitions shall apply:

            (a) "Administrator" means either the Board or a committee of the
Board that is responsible for the administration of the Plan as is designated
from time to time by resolution of the Board.

            (b) "Applicable Laws" means the legal requirements relating to the
administration of employee stock purchase plans, if any, under applicable
provisions of federal securities laws, state corporate and securities laws, the
Code and the applicable regulations thereunder, the rules of any applicable
stock exchange or national market system, and the rules of any foreign
jurisdiction applicable to participation in the Plan by residents therein.

            (c) "Board" means the Board of Directors of the Company.

            (d) "Code" means the Internal Revenue Code of 1986, as amended.

            (e) "Common Stock" means the common stock of the Company.

            (f) "Company" means Dynavax Technologies Corporation, a Delaware
corporation.

            (g) "Compensation" means an Employee's base salary from the Company
or one or more Designated Parents or Subsidiaries, including such amounts of
base salary as are deferred by the Employee (i) under a qualified cash or
deferred arrangement described in Section 401(k) of the Code, or (ii) to a plan
qualified under Section 125 of the Code. Compensation does not include overtime,
bonuses, annual awards, other incentive payments, reimbursements or other
expense allowances, fringe benefits (cash or noncash), moving expenses, deferred
compensation, contributions (other than contributions described in the first
sentence) made on the Employee's behalf by the Company or one or more Designated
Parents or Subsidiaries under any employee benefit or welfare plan now or
hereafter established, and any other payments not specifically referenced in the
first sentence.

            (h) "Corporate Transaction" means any of the following transactions:


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                  (1) a merger or consolidation in which the Company is not the
surviving entity, except for a transaction the principal purpose of which is to
change the state in which the Company is incorporated;

                  (2) the sale, transfer or other disposition of all or
substantially all of the assets of the Company (including the capital stock of
the Company's subsidiary corporations);

                  (3) the complete liquidation or dissolution of the Company;

                  (4) any reverse merger or series of related transactions
culminating in a reverse merger (including, but not limited to, a tender offer
followed by a reverse merger) in which the Company is the surviving entity but
in which securities possessing more than forty percent (40%) of the total
combined voting power of the Company's outstanding securities are transferred to
a person or persons different from those who held such securities immediately
prior to such merger or the initial transaction culminating in such merger but
excluding any such transaction or series of related transactions that the
Administrator determines shall not be a Corporate Transaction; or

                  (5) acquisition in a single or series of related transactions
by any person or related group of persons (other than the Company or by a
Company-sponsored employee benefit plan) of beneficial ownership (within the
meaning of Rule 13d-3 of the Exchange Act) of securities possessing more than
fifty percent (50%) of the total combined voting power of the Company's
outstanding securities but excluding any such transaction or series of related
transactions that the Administrator determines shall not be a Corporate
Transaction.

            (i) "Designated Parents or Subsidiaries" means the Parents or
Subsidiaries which have been designated by the Administrator from time to time
as eligible to participate in the Plan.

            (j) "Effective Date" means the effective date of the Registration
Statement relating to the Company's initial public offering of its Common Stock.
However, should any Parent or Subsidiary become a Designated Parent or
Subsidiary after such date, then the Administrator, in its discretion, shall
designate a separate Effective Date with respect to the employee-participants of
such Designated Parent or Subsidiary.

            (k) "Employee" means any individual, including an officer or
director, who is an employee of the Company or a Designated Parent or Subsidiary
for purposes of Section 423 of the Code. For purposes of the Plan, the
employment relationship shall be treated as continuing intact while the
individual is on sick leave or other leave of absence approved by the
individual's employer. Where the period of leave exceeds ninety (90) days and
the individual's right to reemployment is not guaranteed either by statute or by
contract, the employment relationship will be deemed to have terminated on the
ninety-first (91st) day of such leave, for purposes of determining eligibility
to participate in the Plan.

            (l) "Enrollment Date" means the first day of each Offer Period.

            (m) "Exchange Act" means the Securities Exchange Act of 1934, as
amended.


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            (n) "Exercise Date" means the last day of each Purchase Period.

            (o) "Fair Market Value" means, as of any date, the value of Common
Stock determined as follows:

                  (1) If the Common Stock is listed on any established stock
exchange or a national market system, including without limitation The Nasdaq
National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its
Fair Market Value shall be the closing sales price for such stock (or the
closing bid, if no sales were reported) as quoted on such exchange or system on
the date of determination (or, if no closing sales price or closing bid was
reported on that date, as applicable, on the last trading date such closing
sales price or closing bid was reported), as reported in The Wall Street Journal
or such other source as the Administrator deems reliable;

                  (2) If the Common Stock is regularly quoted on an automated
quotation system (including the OTC Bulletin Board) or by a recognized
securities dealer, its Fair Market Value shall be the closing sales price for
such stock as quoted on such system on the date of determination, but if selling
prices are not reported, the Fair Market Value of a share of Common Stock shall
be the mean between the high bid and low asked prices for the Common Stock on
the date of determination (or, if no such prices were reported on that date, on
the last date such prices were reported), as reported in The Wall Street Journal
or such other source as the Administrator deems reliable; or

                  (3) In the absence of an established market for the Common
Stock of the type described in (1) and (2), above, the Fair Market Value thereof
shall be determined by the Administrator in good faith.

                  (4) On the initial Effective Date of the Plan, the Fair Market
Value shall be the price at which the Board, or if applicable, the Pricing
Committee of the Board, and the underwriters agree to offer the Common Stock to
the public in the initial public offering of the Common Stock.

            (p) "Offer Period" means an Offer Period established pursuant to
Section 4 hereof.

            (q) "Parent" means a "parent corporation" of the Company, whether
now or hereafter existing, as defined in Section 424(e) of the Code.

            (r) "Participant" means an Employee of the Company or Designated
Parent or Subsidiary who has completed a subscription agreement as set forth in
Section 5(a) and is thereby enrolled in the Plan.

            (s) "Plan" means this Employee Stock Purchase Plan.

            (t) "Purchase Period" means a period of approximately six months,
commencing on February 15 and August 15 of each year and terminating on the next
following August 14 or February 14, respectively; provided, however, that the
first Purchase Period shall commence on the Effective Date and shall end on
August 14, 2004.


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            (u) "Purchase Price" shall mean an amount equal to 85% of the Fair
Market Value of a share of Common Stock on the Enrollment Date or on the
Exercise Date, whichever is lower.

            (v) "Reserves" means, as of any date, the sum of (1) the number of
shares of Common Stock covered by each then outstanding option under the Plan
which has not yet been exercised and (2) the number of shares of Common Stock
which have been authorized for issuance under the Plan but not then subject to
an outstanding option.

            (w) "Subsidiary" means a "subsidiary corporation" of the Company,
whether now or hereafter existing, as defined in Section 424(f) of the Code.

      3. Eligibility.

            (a) General. Any individual who is an Employee on a given Enrollment
Date shall be eligible to participate in the Plan for the Offer Period
commencing with such Enrollment Date. No individual who is not an Employee shall
be eligible to participate in the Plan.

            (b) Limitations on Grant and Accrual. Any provisions of the Plan to
the contrary notwithstanding, no Employee shall be granted an option under the
Plan (i) if, immediately after the grant, such Employee (taking into account
stock owned by any other person whose stock would be attributed to such Employee
pursuant to Section 424(d) of the Code) would own stock and/or hold outstanding
options to purchase stock possessing five percent (5%) or more of the total
combined voting power or value of all classes of stock of the Company or of any
Parent or Subsidiary, or (ii) which permits the Employee's rights to purchase
stock under all employee stock purchase plans of the Company and its Parents or
Subsidiaries to accrue at a rate which exceeds Twenty-Five Thousand Dollars
(US$25,000) worth of stock (determined at the Fair Market Value of the shares at
the time such option is granted) for each calendar year in which such option is
outstanding at any time. The determination of the accrual of the right to
purchase stock shall be made in accordance with Section 423(b)(8) of the Code
and the regulations thereunder.

            (c) Other Limits on Eligibility. Notwithstanding SubSection (a),
above, the following Employees shall not be eligible to participate in the Plan
for any relevant Offer Period: (i) Employees whose customary employment is 20
hours or less per week; (ii) Employees whose customary employment is for not
more than 5 months in any calendar year; and (iii) Employees who are subject to
rules or laws of a foreign jurisdiction that prohibit or make impractical the
participation of such Employees in the Plan.

      4. Offer Periods.

            (a) The Plan shall be implemented through overlapping or consecutive
Offer Periods until such time as (i) the maximum number of shares of Common
Stock available for issuance under the Plan shall have been purchased or (ii)
the Plan shall have been sooner terminated in accordance with Section 19 hereof.
The maximum duration of an Offer Period shall be twenty-seven (27) months.
Initially, the Plan shall be implemented through overlapping Offer Periods of
twenty-four (24) months' duration commencing each February 15 and


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August 15 following the Effective Date (except that the initial Offer Period
shall commence on the Effective Date and shall end on February 14, 2006).

            (b) A Participant shall be granted a separate option for each Offer
Period in which he or she participates. The option shall be granted on the
Enrollment Date and shall be automatically exercised in successive installments
on the Exercise Dates ending within the Offer Period.

            (c) If on the first day of any Purchase Period in an Offer Period in
which an Employee is a Participant, the Fair Market Value of the Common Stock is
less than the Fair Market Value of the Common Stock on the Enrollment Date of
the Offer Period (after taking into account any adjustment during the Offer
Period pursuant to Section 18(a)), the Offer Period shall be terminated
automatically and the Participant shall be enrolled automatically in the new
Offer Period which has its first Purchase Period commencing on that date,
provided the Employee is eligible to participate in the Plan on that date and
has not elected to terminate participation in the Plan.

            (d) Except as specifically provided herein, the acquisition of
Common Stock through participation in the Plan for any Offer Period shall
neither limit nor require the acquisition of Common Stock by a Participant in
any subsequent Offer Period.

      5. Participation.

            (a) All Employees eligible to participate in the Plan as of the
first Enrollment Date of the Plan shall automatically become a Participant in
the initial Offer Period and be eligible to make a direct payment for shares of
the Common Stock on the Exercise Date of the first Purchase Period of the
initial Offer Period in an amount equal to the lesser of the aggregate Purchase
Price for 2,500 shares of the Common Stock or ten percent (10%) of the
Compensation that he or she receives during the first Purchase Period of the
initial Offer Period, unless a change of status notice in the form of Exhibit C
(or such other form or method (including electronic forms) as the Administrator
may designate from time to time) is filed to the contrary or the Participant
withdraws from the Plan as provided in Section 10. No subscription agreement
need be filed by the Participant with the Company in order to participate in the
initial Offer Period.

            (b) After the initial Offer Period, an eligible Employee may become
a Participant in the Plan by completing a subscription agreement authorizing
payroll deductions in the form of Exhibit A to this Plan (or such other form or
method (including electronic forms) as the Administrator may designate from time
to time) and filing it with the designated payroll office of the Company at
least five (5) business days prior to the Enrollment Date for the Offer Period
in which such participation will commence, unless a later time for filing the
subscription agreement is set by the Administrator for all eligible Employees
with respect to a given Offer Period.

            (c) No payroll deductions shall be made for Participants during the
first Purchase Period of the initial Offer Period, unless a change of status
notice in the form of Exhibit C to this Plan (or such other form or method
(including electronic forms) as the Administrator may designate from time to
time) authorizing the commencement of payroll


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deductions is filed by the Participant with the Company after a registration
statement on Form S-8 has been filed with the Securities Exchange Commission
with respect to the shares being offered under the Plan. If so elected, the rate
of payroll deductions during the first Purchase Period of the initial Offer
Period may exceed the maximum permitted rate under Section 6(a) to make-up for
missed payroll deductions that would otherwise have been made prior to the
filing of the Form S-8 with respect to the Plan. Payroll deductions for a
Participant in the initial Offer Period shall commence at the rate elected by
the Participant under Section 6(a) with the first partial or full payroll period
beginning on the first day of the second Purchase Period of the initial Offer
Period and shall end on the last complete payroll period during the initial
Offer Period, unless a change of status notice in the form of Exhibit B (or such
other form or method (including electronic forms) as the Administrator may
designate from time to time) is filed to the contrary or the Participant
withdraws from the Plan as provided in Section 10. No direct payment for shares
shall be permitted after the first Purchase Period of the initial Offer Period.
Therefore, Participants in the initial Offer Period must file the change of
status notice in the form of Exhibit C to this Plan (or such other form or
method (including electronic forms) as the Administrator may designate from time
to time) prior to the commencement of the second Purchase Period of the initial
Offer Period to assure maximum participation rights under the Plan.

            (d) For Offer Periods, other than the initial Offer Period, payroll
deductions for a Participant shall commence with the first partial or full
payroll period beginning on the Enrollment Date and shall end on the last
complete payroll period during the Offer Period, unless sooner terminated by the
Participant as provided in Section 10.

      6. Payroll Deductions.

            (a) At the time a Participant files a subscription agreement, the
Participant shall elect to have payroll deductions made during the Offer Period
in amounts between one percent (1%) and not exceeding ten percent (10%) of the
Compensation which the Participant receives during the Offer Period.

            (b) All payroll deductions made for a Participant shall be credited
to the Participant's account under the Plan and will be withheld in whole
percentages only. A Participant may not make any additional payments into such
account.

            (c) A Participant may discontinue participation in the Plan as
provided in Section 10, or may increase or decrease the rate of payroll
deductions during the Offer Period by completing and filing with the Company a
change of status notice in the form of Exhibit B to this Plan (or such other
form or method (including electronic forms) as the Administrator may designate
from time to time) authorizing an increase or decrease in the payroll deduction
rate. During the first Purchase Period of the initial Offer Period, a
Participant may discontinue participation in the Plan as provided in Section 10
or initiate payroll deductions by completing and filing with the Company a
change of status notice in the form of Exhibit C to this Plan (or such other
form or method (including electronic forms) as the Administrator may designate
from time to time). Any increase or decrease in the rate of a Participant's
payroll deductions shall be effective with the first full payroll period
commencing five (5) business days after the Company's receipt of the change of
status notice unless the Company elects to process a given


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change in participation more quickly. A Participant's subscription agreement (as
modified by any change of status notice) shall remain in effect for successive
Offer Periods unless terminated as provided in Section 10. The Administrator
shall be authorized to limit the number of payroll deduction rate changes during
any Offer Period.

            (d) Notwithstanding the foregoing, to the extent necessary to comply
with Section 423(b)(8) of the Code and Section 3(b) herein, a Participant's
payroll deductions shall be decreased to 0%. Payroll deductions shall recommence
at the rate provided in such Participant's subscription agreement, as amended,
at the time when permitted under Section 423(b)(8) of the Code and Section 3(b)
herein, unless such participation is sooner terminated by the Participant as
provided in Section 10.

      7. Grant of Option. On the Enrollment Date, each Participant shall be
granted an option to purchase (at the applicable Purchase Price) 10,000 shares
of the Common Stock, subject to adjustment as provided in Section 18 hereof;
provided (i) that such option shall be subject to the limitations set forth in
Sections 3(b), 6 and 12 hereof, and (ii) the maximum number of shares of Common
Stock a Participant shall be permitted to purchase in any Purchase Period shall
be 2,500 shares, subject to adjustment as provided in Section 18 hereof.1
Exercise of the option shall occur as provided in Section 8, unless the
Participant has withdrawn pursuant to Section 10, and the option, to the extent
not exercised, shall expire on the last day of the Offer Period with respect to
which such option was granted. Notwithstanding the foregoing, shares subject to
the option may only be purchased with accumulated payroll deductions credited to
a Participant's account in accordance with Section 6 of the Plan. In addition,
to the extent an option is not exercised on each Purchase Date, the option shall
lapse and thereafter cease to be exercisable.

      8. Exercise of Option. Unless a Participant withdraws from the Plan as
provided in Section 10, below, the Participant's option for the purchase of
shares of Common Stock will be exercised automatically on each Exercise Date, by
applying the accumulated payroll deductions in the Participant's account to
purchase the number of full shares subject to the option by dividing such
Participant's payroll deductions accumulated prior to such Exercise Date and
retained in the Participant's account as of the Exercise Date by the applicable
Purchase Price, provided, however, that if a Participant is eligible to purchase
any shares on the first Exercise Date of the initial Offer Period by direct
payment, the Participant's option for the purchase of shares will be exercised
to the extent possible by applying the direct payment amount made by the
Participant to purchase the number of full shares subject to the option by
dividing such direct payment amount by the applicable Purchase Price and,
provided, further, in no event may the accumulated payroll deductions and direct
payment amounts applied to the purchase of shares on the first Exercise Date of
the initial Offer Period exceed the amount specified in Section 5(a). No
fractional shares will be purchased; any payroll deductions accumulated in a
Participant's account which are not sufficient to purchase a full share shall be
carried over to the next Purchase Period or Offer Period, whichever applies, or
returned to the Participant, if the Participant withdraws from the Plan. Any
direct payment amounts which are not sufficient to purchase a full share shall
be returned to the Participant. Notwithstanding the foregoing, any amount
remaining in a Participant's account or any excess direct payment amount
following the


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1     All Share numbers in the Plan reflect the one-for-three reverse stock
      split which occurred on _________, 2004.


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purchase of shares on the Exercise Date due to the application of Section
423(b)(8) of the Code or Section 7, above, shall be returned to the Participant
and shall not be carried over to the next Offer Period or Purchase Period.
During a Participant's lifetime, a Participant's option to purchase shares
hereunder is exercisable only by the Participant.

      9. Delivery. Upon receipt of a request from a Participant after each
Exercise Date on which a purchase of shares occurs, the Company shall arrange
the delivery to such Participant, as promptly as practicable, of a certificate
representing the shares purchased upon exercise of the Participant's option.

      10. Withdrawal; Termination of Employment.

            (a) A Participant may either (i) withdraw all but not less than all
the payroll deductions credited to the Participant's account and not yet used to
exercise the Participant's option under the Plan or (ii) terminate future
payroll deductions, but allow accumulated payroll deductions to be used to
exercise the Participant's option under the Plan at any time by giving written
notice to the Company in the form of Exhibit B to this Plan (or such other form
or method (including electronic forms) as the Administrator may designate from
time to time). During the first Purchase Period of the initial Offer Period, a
Participant may elect to withdraw from the Plan and not purchase shares by
direct payment by giving written notice to the Company in the form of Exhibit C
to this Plan (or such other form or method (including electronic forms) as the
Administrator may designate from time to time). If the Participant elects
withdrawal alternative (i) described above, all of the Participant's payroll
deductions credited to the Participant's account will be paid to such
Participant as promptly as practicable after receipt of notice of withdrawal,
such Participant's option for the Offer Period will be automatically terminated,
and no further payroll deductions for the purchase of shares will be made during
the Offer Period. If the Participant elects withdrawal alternative (ii)
described above, no further payroll deductions for the purchase of shares will
be made during the Offer Period, all of the Participant's payroll deductions
credited to the Participant's account will be applied to the exercise of the
Participant's option on the next Exercise Date (subject to Sections 3(b), 6, 7
and 12), and after such Exercise Date, such Participant's option for the Offer
Period will be automatically terminated and all remaining accumulated payroll
deduction amounts shall be returned to the Participant. If a Participant
withdraws from an Offer Period, payroll deductions will not resume at the
beginning of the succeeding Offer Period unless the Participant delivers to the
Company a new subscription agreement.

            (b) Upon termination of a Participant's employment relationship (as
described in Section 2(k)) at a time more than three (3) months from the next
scheduled Exercise Date, the payroll deductions credited to such Participant's
account during the Offer Period but not yet used to exercise the option will be
returned to such Participant or, in the case of his/her death, to the person or
persons entitled thereto under Section 14, and such Participant's option will be
automatically terminated without exercise of any portion of such option. Upon
termination of a Participant's employment relationship (as described in Section
2(k)) within three (3) months of the next scheduled Exercise Date, the payroll
deductions credited to such Participant's account during the Offer Period but
not yet used to exercise the option will be applied to the purchase of Common
Stock on the next Exercise Date, unless the Participant (or in the case of the
Participant's death, the person or persons entitled to the Participant's account
balance under


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Section 14) withdraws from the Plan by submitting a change of status notice in
accordance with subSection (a) of this Section 10. In such a case, no further
payroll deductions will be credited to the Participant's account following the
Participant's termination of employment and the Participant's option under the
Plan will be automatically terminated after the purchase of Common Stock on the
next scheduled Exercise Date.

      11. Interest. No interest shall accrue on the payroll deductions credited
to a Participant's account under the Plan.

      12. Stock.

            (a) Subject to adjustment upon changes in capitalization of the
Company as provided in Section 18, the maximum number of shares of Common Stock
which shall be made available for sale under the Plan shall be 250,000 shares,
plus an annual increase to be added on the first business day of each Calendar
year beginning in 2005 equal to the lesser of (i) 250,000 shares, (ii) one
percent (1%) of the outstanding shares of Common Stock on such date, or (iii) a
lesser number of shares determined by the Administrator.2 With respect to any
amendment to increase the total number of shares of Common Stock under the Plan,
the Administrator shall have discretion to disallow the purchase of any
increased shares of Common Stock for Offer Periods in existence prior to such
increase. If the Administrator determines that on a given Exercise Date the
number of shares with respect to which options are to be exercised may exceed
(x) the number of shares then available for sale under the Plan or (y) the
number of shares available for sale under the Plan on the Enrollment Date(s) of
one or more of the Offer Periods in which such Exercise Date is to occur, the
Administrator may make a pro rata allocation of the shares remaining available
for purchase on such Enrollment Dates or Exercise Date, as applicable, in as
uniform a manner as shall be practicable and as it shall determine to be
equitable, and shall either continue all Offer Periods then in effect or
terminate any one or more Offer Periods then in effect pursuant to Section 19,
below. Any amount remaining in a Participant's payroll account following such
pro rata allocation shall be returned to the Participant and shall not be
carried over to any future Purchase Period or Offer Period, as determined by the
Administrator.

            (b) A Participant will have no interest or voting right in shares
covered by the Participant's option until such shares are actually purchased on
the Participant's behalf in accordance with the applicable provisions of the
Plan. No adjustment shall be made for dividends, distributions or other rights
for which the record date is prior to the date of such purchase.

            (c) Shares to be delivered to a Participant under the Plan will be
registered in the name of the Participant or in the name of the Participant and
his or her spouse, as designated in the Participant's subscription agreement.

      13. Administration. The Plan shall be administered by the Administrator
which shall have full and exclusive discretionary authority to construe,
interpret and apply the terms of the Plan, to determine eligibility and to
adjudicate all disputed claims filed under the Plan. Every

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2     All Share numbers in the Plan reflect the one-for-three reverse stock
      split which occurred on _________, 2004.


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finding, decision and determination made by the Administrator shall, to the full
extent permitted by Applicable Law, be final and binding upon all persons.

      14. Designation of Beneficiary.

            (a) Each Participant will file a written designation of a
beneficiary who is to receive any shares and cash, if any, from the
Participant's account under the Plan in the event of such Participant's death.
If a Participant is married and the designated beneficiary is not the spouse,
spousal consent shall be required for such designation to be effective.

            (b) Such designation of beneficiary may be changed by the
Participant (and the Participant's spouse, if any) at any time by written
notice. In the event of the death of a Participant and in the absence of a
beneficiary validly designated under the Plan who is living (or in existence) at
the time of such Participant's death, the Company shall deliver such shares
and/or cash to the executor or administrator of the estate of the Participant,
or if no such executor or administrator has been appointed (to the knowledge of
the Administrator), the Administrator shall deliver such shares and/or cash to
the spouse (or domestic partner, as determined by the Administrator) of the
Participant, or if no spouse (or domestic partner) is known to the
Administrator, then to the issue of the Participant, such distribution to be
made per stirpes (by right of representation), or if no issue are known to the
Administrator, then to the heirs at law of the Participant determined in
accordance with Section 27.

      15. Transferability. No payroll deductions credited to a Participant's
account, options granted hereunder, or any rights with regard to the exercise of
an option or to receive shares under the Plan may be assigned, transferred,
pledged or otherwise disposed of in any way (other than by will, the laws of
descent and distribution, or as provided in Section 14 hereof) by the
Participant. Any such attempt at assignment, transfer, pledge or other
disposition shall be without effect, except that the Administrator may, in its
sole discretion, treat such act as an election to withdraw funds from an Offer
Period in accordance with Section 10.

      16. Use of Funds. All payroll deductions received or held by the Company
under the Plan may be used by the Company for any corporate purpose, and the
Company shall not be obligated to segregate such payroll deductions or hold them
exclusively for the benefit of Participants. All payroll deductions received or
held by the Company may be subject to the claims of the Company's general
creditors. Participants shall have the status of general unsecured creditors of
the Company. Any amounts payable to Participants pursuant to the Plan shall be
unfunded and unsecured obligations for all purposes, including, without
limitation, Title I of the Employee Retirement Income Security Act of 1974, as
amended. The Company shall retain at all times beneficial ownership of any
investments, including trust investments, which the Company may make to fulfill
its payment obligations hereunder. Any investments or the creation or
maintenance of any trust or any Participant account shall not create or
constitute a trust or fiduciary relationship between the Administrator, the
Company or any Designated Parent or Subsidiary and a Participant, or otherwise
create any vested or beneficial interest in any Participant or the Participant's
creditors in any assets of the Company or a Designated Parent or Subsidiary. The
Participants shall have no claim against the Company or any Designated Parent or
Subsidiary for any changes in the value of any assets that may be invested or
reinvested by the Company with respect to the Plan.


                                       10
<PAGE>
      17. Reports. Individual accounts will be maintained for each Participant
in the Plan. Statements of account will be given to Participants at least
annually, which statements will set forth the amounts of payroll deductions, the
Purchase Price, the number of shares purchased and the remaining cash balance,
if any.

      18. Adjustments Upon Changes in Capitalization; Corporate Transactions.

            (a) Adjustments Upon Changes in Capitalization. Subject to any
required action by the stockholders of the Company, the Reserves, the Purchase
Price, the maximum number of shares that may be purchased in any Offer Period or
Purchase Period, as well as any other terms that the Administrator determines
require adjustment shall be proportionately adjusted for (i) any increase or
decrease in the number of issued shares of Common Stock resulting from a stock
split, reverse stock split, stock dividend, combination or reclassification of
the Common Stock, (ii) any other increase or decrease in the number of issued
shares of Common Stock effected without receipt of consideration by the Company,
or (iii) as the Administrator may determine in its discretion, any other
transaction with respect to Common Stock including a corporate merger,
consolidation, acquisition of property or stock, separation (including a
spin-off or other distribution of stock or property), reorganization,
liquidation (whether partial or complete) or any similar transaction; provided,
however that conversion of any convertible securities of the Company shall not
be deemed to have been "effected without receipt of consideration." Such
adjustment shall be made by the Administrator and its determination shall be
final, binding and conclusive. Except as the Administrator determines, no
issuance by the Company of shares of stock of any class, or securities
convertible into shares of stock of any class, shall affect, and no adjustment
by reason hereof shall be made with respect to, the Reserves and the Purchase
Price.

            (b) Corporate Transactions. In the event of a proposed Corporate
Transaction, each option under the Plan shall be assumed by such successor
corporation or a parent or subsidiary of such successor corporation, unless the
Administrator, in the exercise of its sole discretion and in lieu of such
assumption, determines to shorten the Offer Period then in progress by setting a
new Exercise Date (the "New Exercise Date"). If the Administrator shortens the
Offer Period then in progress in lieu of assumption in the event of a Corporate
Transaction, the Administrator shall notify each Participant in writing at least
ten (10) business days prior to the New Exercise Date, that the Exercise Date
for the Participant's option has been changed to the New Exercise Date and that
either:

                  (1) the Participant's option will be exercised automatically
on the New Exercise Date, unless prior to such date the Participant has
withdrawn from the Offer Period as provided in Section 10; or

                  (2) the Company shall pay to the Participant on the New
Exercise Date an amount in cash, cash equivalents, or property as determined by
the Administrator that is equal to the difference in the Fair Market Value of
the shares subject to the option and the Purchase Price due had the
Participant's option been exercised automatically under SubSection (b)(i) above.


                                       11
<PAGE>
      For purposes of this Subsection, an option granted under the Plan shall be
deemed to be assumed if, in connection with the Corporate Transaction, the
option is replaced with a comparable option with respect to shares of capital
stock of the successor corporation or Parent thereof. The determination of
option comparability shall be made by the Administrator prior to the Corporate
Transaction and its determination shall be final, binding and conclusive on all
persons.

      19. Amendment or Termination.

            (a) The Administrator may at any time and for any reason terminate
or amend the Plan. Except as provided in Section 18, no such termination can
affect options previously granted, provided that the Plan or any one or more
Offer Periods may be terminated by the Administrator on any Exercise Date or by
the Administrator establishing a new Exercise Date with respect to any Offer
Period and/or any Purchase Period then in progress if the Administrator
determines that the termination of the Plan or such one or more Offer Periods is
in the best interests of the Company and its stockholders. Except as provided in
Section 18 and this Section 19, no amendment may make any change in any option
theretofore granted which adversely affects the rights of any Participant
without the consent of affected Participants. To the extent necessary to comply
with Section 423 of the Code (or any successor rule or provision or any other
Applicable Law), the Company shall obtain stockholder approval in such a manner
and to such a degree as required.

            (b) Without stockholder consent and without regard to whether any
Participant rights may be considered to have been "adversely affected," the
Administrator shall be entitled to limit the frequency and/or number of changes
in the amount withheld during Offer Periods, change the length of Purchase
Periods within any Offer Period, determine the length of any future Offer
Period, determine whether future Offer Periods shall be consecutive or
overlapping, establish the exchange ratio applicable to amounts withheld in a
currency other than U.S. dollars, establish additional terms, conditions, rules
or procedures to accommodate the rules or laws of applicable foreign
jurisdictions, permit payroll withholding in excess of the amount designated by
a Participant in order to adjust for delays or mistakes in the Company's
processing of properly completed withholding elections, establish reasonable
waiting and adjustment periods and/or accounting and crediting procedures to
ensure that amounts applied toward the purchase of Common Stock for each
Participant properly correspond with amounts withheld from the Participant's
Compensation, and establish such other limitations or procedures as the
Administrator determines in its sole discretion advisable and which are
consistent with the Plan.

      20. Notices. All notices or other communications by a Participant to the
Company under or in connection with the Plan shall be deemed to have been duly
given when received in the form specified by the Administrator at the location,
or by the person, designated by the Administrator for the receipt thereof.

      21. Conditions Upon Issuance of Shares. Shares shall not be issued with
respect to an option unless the exercise of such option and the issuance and
delivery of such shares pursuant thereto shall comply with all Applicable Laws
and shall be further subject to the approval of counsel for the Company with
respect to such compliance. As a condition to the exercise of an option, the
Company may require the Participant to represent and warrant at the time of any
such


                                       12
<PAGE>
exercise that the shares are being purchased only for investment and without any
present intention to sell or distribute such shares if, in the opinion of
counsel for the Company, such a representation is required by any of the
aforementioned Applicable Laws. In addition, no options shall be exercised or
shares issued hereunder before the Plan shall have been approved by stockholders
of the Company as provided in Section 23.

      22. Term of Plan. The Plan shall become effective upon the earlier to
occur of its adoption by the Board or its approval by the stockholders of the
Company. It shall continue in effect for a term of ten (10) years unless sooner
terminated under Section 19.

      23. Stockholder Approval. Continuance of the Plan shall be subject to
approval by the stockholders of the Company within twelve (12) months before or
after the date the Plan is adopted. Such stockholder approval shall be obtained
in the degree and manner required under Applicable Laws.

      24. No Employment Rights. The Plan does not, directly or indirectly,
create any right for the benefit of any employee or class of employees to
purchase any shares under the Plan, or create in any employee or class of
employees any right with respect to continuation of employment by the Company or
a Designated Parent or Subsidiary, and it shall not be deemed to interfere in
any way with such employer's right to terminate, or otherwise modify, an
employee's employment at any time.

      25. No Effect on Retirement and Other Benefit Plans. Except as
specifically provided in a retirement or other benefit plan of the Company or a
Designated Parent or Subsidiary, participation in the Plan shall not be deemed
compensation for purposes of computing benefits or contributions under any
retirement plan of the Company or a Designated Parent or Subsidiary, and shall
not affect any benefits under any other benefit plan of any kind or any benefit
plan subsequently instituted under which the availability or amount of benefits
is related to level of compensation. The Plan is not a "Retirement Plan" or
"Welfare Plan" under the Employee Retirement Income Security Act of 1974, as
amended.

      26. Effect of Plan. The provisions of the Plan shall, in accordance with
its terms, be binding upon, and inure to the benefit of, all successors of each
Participant, including, without limitation, such Participant's estate and the
executors, administrators or trustees thereof, heirs and legatees, and any
receiver, trustee in bankruptcy or representative of creditors of such
Participant.

      27. Governing Law. The Plan is to be construed in accordance with and
governed by the internal laws of the State of California without giving effect
to any choice of law rule that would cause the application of the laws of any
jurisdiction other than the internal laws of the State of California to the
rights and duties of the parties, except to the extent the internal laws of the
State of California are superseded by the laws of the United States. Should any
provision of the Plan be determined by a court of law to be illegal or
unenforceable, the other provisions shall nevertheless remain effective and
shall remain enforceable.

      28. Dispute Resolution. The provisions of this Section 28 (and as restated
in the Subscription Agreement) shall be the exclusive means of resolving
disputes arising out of or


                                       13
<PAGE>
relating to the Plan. The Company and the Participant, or their respective
successors (the "parties"), shall attempt in good faith to resolve any disputes
arising out of or relating to the Plan by negotiation between individuals who
have authority to settle the controversy. Negotiations shall be commenced by
either party by notice of a written statement of the party's position and the
name and title of the individual who will represent the party. Within thirty
(30) days of the written notification, the parties shall meet at a mutually
acceptable time and place, and thereafter as often as they reasonably deem
necessary, to resolve the dispute. If the dispute has not been resolved by
negotiation, the parties agree that any suit, action, or proceeding arising out
of or relating to the Plan shall be brought in the United States District Court
for the Northern District of California (or should such court lack jurisdiction
to hear such action, suit or proceeding, in a California state court in the
County of San Francisco) and that the parties shall submit to the jurisdiction
of such court. The parties irrevocably waive, to the fullest extent permitted by
law, any objection the party may have to the laying of venue for any such suit,
action or proceeding brought in such court. THE PARTIES ALSO EXPRESSLY WAIVE ANY
RIGHT THEY HAVE OR MAY HAVE TO A JURY TRIAL OF ANY SUCH SUIT, ACTION OR
PROCEEDING. If any one or more provisions of this Section 28 shall for any
reason be held invalid or unenforceable, it is the specific intent of the
parties that such provisions shall be modified to the minimum extent necessary
to make it or its application valid and enforceable.


                                       14
<PAGE>
                                    EXHIBIT A

              Dynavax Technologies Corporation 2004 Employee Stock Purchase Plan
                                                          SUBSCRIPTION AGREEMENT

                                   Effective with the Offer Period beginning on:

            [ ] ESPP Effective Date [ ] August 15, 2004 or [ ] February 15, 2005


1.    PERSONAL INFORMATION [MODIFY DATA REQUESTED AS APPROPRIATE]

<TABLE>
<S>                                                      <C>
Legal Name (Please Print)
                          -----------------------------  ----------  -----------
                          (Last)     (First)      (MI)   Location    Department

Street Address
               ----------------------------------------  -----------------------
                                                         Daytime Telephone

City, State/Country, Zip
                        -------------------------------  -----------------------
                                                         E-Mail Address

Social Security No.   -   -        Employee I.D. No.
                   --- --- --------                      -----------------------
                                                         Manager   Mgr. Location
</TABLE>

2.    ELIGIBILITY Any Employee whose customary employment is more than 20 hours
      per week and more than 5 months per calendar year and who does not hold
      (directly or indirectly) five percent (5%) or more of the combined voting
      power of the Company, a parent or a subsidiary, whether in stock or
      options to acquire stock is eligible to participate in the Dynavax
      Technologies Corporation 2004 Employee Stock Purchase Plan (the "ESPP");
      provided, however, that Employees who are subject to the rules or laws of
      a foreign jurisdiction that prohibit or make impractical the participation
      of such Employees in the ESPP are not eligible to participate.

3.    DEFINITIONS Each capitalized term in this Subscription Agreement shall
      have the meaning set forth in the ESPP.

4.    SUBSCRIPTION I hereby elect to participate in the ESPP and subscribe to
      purchase shares of the Company's Common Stock in accordance with this
      Subscription Agreement and the ESPP. I have received a complete copy of
      the ESPP and a prospectus describing the ESPP and understand that my
      participation in the ESPP is in all respects subject to the terms of the
      ESPP. The effectiveness of this Subscription Agreement is dependent on my
      eligibility to participate in the ESPP.

5.    PAYROLL DEDUCTION AUTHORIZATION I hereby authorize payroll deductions from
      my Compensation during the Offer Period in the percentage specified below
      (payroll reductions may not exceed 10% of Compensation nor the limitation
      under Section 423(b)(8) of the Code and the regulations thereunder):

      Percentage to be Deducted (circle one) 1%   2%   3%   4%   5%   6%   7%
                                        8%   9%   10%

6.    ESPP ACCOUNTS AND PURCHASE PRICE I understand that all payroll deductions
      will be credited to my account under the ESPP. No additional payments may
      be made to my account. No interest will be credited on funds held in the
      account at any time including any refund of the account caused by
      withdrawal from the ESPP. All payroll deductions shall be accumulated for
      the purchase of Company Common Stock at the applicable Purchase Price
      determined in accordance with the ESPP.

7.    WITHDRAWAL AND CHANGES IN PAYROLL DEDUCTION I understand that I may
      discontinue my participation in the ESPP at any time prior to an Exercise
      Date as provided in Section 10 of the


                                       A-1
<PAGE>
      ESPP, but if I do not withdraw from the ESPP, any accumulated payroll
      deductions will be applied automatically to purchase Company Common Stock.
      I may increase or decrease the rate of my payroll deductions in whole
      percentage increments to not less than one percent (1%) on one occasion
      during any Purchase Period by completing and timely filing a Change of
      Status Notice. Any increase or decrease will be effective for the full
      payroll period occurring after five (5) business days from the Company's
      receipt of the Change of Status Notice.


8.    PERPETUAL SUBSCRIPTION I understand that this Subscription Agreement shall
      remain in effect for successive Offer Periods until I withdraw from
      participation in the ESPP, or termination of the ESPP.

9.    TAXES I have reviewed the ESPP prospectus discussion of the federal tax
      consequences of participation in the ESPP and consulted with tax
      consultants as I deemed advisable prior to my participation in the ESPP. I
      hereby agree to notify the Company in writing within thirty (30) days of
      any disposition (transfer or sale) of any shares purchased under the ESPP
      if such disposition occurs within two (2) years of the Enrollment Date
      (the first day of the Offer Period during which the shares were purchased)
      or within one (1) year of the Exercise Date (the date I purchased such
      shares), and I will make adequate provision to the Company for foreign,
      federal, state or other tax withholding obligations, if any, which arise
      upon the disposition of the shares. In addition, the Company may withhold
      from my Compensation any amount necessary to meet applicable tax
      withholding obligations incident to my participation in the ESPP,
      including any withholding necessary to make available to the Company any
      tax deductions or benefits contingent on such withholding.


10.   DISPUTE RESOLUTION The provisions of this Section 10 and Section 28 of the
      ESPP shall be the exclusive means of resolving disputes arising out of or
      relating to the Plan. The Company and I, or our respective successors (the
      "parties"), shall attempt in good faith to resolve any disputes arising
      out of or relating to the Plan by negotiation between individuals who have
      authority to settle the controversy. Negotiations shall be commenced by
      either party by notice of a written statement of the party's position and
      the name and title of the individual who will represent the party. Within
      thirty (30) days of the written notification, the parties shall meet at a
      mutually acceptable time and place, and thereafter as often as they
      reasonably deem necessary, to resolve the dispute. If the dispute has not
      been resolved by negotiation, the Company and I agree that any suit,
      action, or proceeding arising out of or relating to the Plan shall be
      brought in the United States District Court for the Northern District of
      California (or should such court lack jurisdiction to hear such action,
      suit or proceeding, in a California state court in the County of San
      Francisco) and that we shall submit to the jurisdiction of such court. The
      Company and I irrevocably waive, to the fullest extent permitted by law,
      any objection we may have to the laying of venue for any such suit, action
      or proceeding brought in such court. THE COMPANY AND I ALSO EXPRESSLY
      WAIVE ANY RIGHT WE HAVE OR MAY HAVE TO A JURY TRIAL OF ANY SUCH SUIT,
      ACTION OR PROCEEDING. If any one or more provisions of this Section 10 or
      Section 28 of the ESPP shall for any reason be held invalid or
      unenforceable, it is the specific intent of the Company and I that such
      provisions shall be modified to the minimum extent necessary to make it or
      its application valid and enforceable.

11.   DESIGNATION OF BENEFICIARY In the event of my death, I hereby designate
      the following person or trust as my beneficiary to receive all payments
      and shares due to me under the ESPP:

            [ ]  I am single       [ ]  I am married

<TABLE>
<S>                                                                                <C>
Beneficiary (please print)                                                         Relationship to Beneficiary (if any)
                           -----------------------------------------------------
                               (Last)              (First)              (MI)

Street Address
               -----------------------------------------------------------------   --------------------------------------
</TABLE>


                                      A-2
<PAGE>
City, State/Country, Zip
                         -------------------------------------------------------


12.   TERMINATION OF ESPP I understand that the Company has the right,
      exercisable in its sole discretion, to amend or terminate the ESPP at any
      time, and a termination may be effective as early as an Exercise Date,
      including the establishment of an alternative date for an Exercise Date
      within each outstanding Offer Period.

      Date:                  Employee Signature:
            --------------                      --------------------------------


                                                --------------------------------
                                                spouse's signature (if
                                                beneficiary is other
                                                than spouse)


                                      A-3
<PAGE>
                                    EXHIBIT B

              Dynavax Technologies Corporation 2004 Employee Stock Purchase Plan
                                                         CHANGE OF STATUS NOTICE

--------------------------------------------------------------
  Participant Name (Please Print)

--------------------------------------------------------------
  Social Security Number

================================================================================

      WITHDRAWAL FROM ESPP

      I hereby withdraw from the Dynavax Technologies Corporation 2004 Employee
      Stock Purchase Plan (the "ESPP") and agree that my option under the
      applicable Offer Period will be automatically terminated and all
      accumulated payroll deductions credited to my account will be refunded to
      me or applied to the purchase of Common Stock depending on the alternative
      indicated below. No further payroll deductions will be made for the
      purchase of shares in the applicable Offer Period and I shall be eligible
      to participate in a future Offer Period only by timely delivery to the
      Company of a new Subscription Agreement.

[ ]   WITHDRAWAL AND PURCHASE OF COMMON STOCK

      Payroll deductions will terminate, but your account balance will be
      applied to purchase Common Stock on the next Exercise Date. Any remaining
      balance will be refunded.

[ ]   WITHDRAWAL WITHOUT PURCHASE OF COMMON STOCK

      Entire account balance will be refunded to me and no Common Stock will be
      purchased on the next Exercise Date provided this notice is submitted to
      the Company ten (10) business days prior to the next Exercise Date.

================================================================================

[ ]   CHANGE IN PAYROLL DEDUCTION

      I hereby elect to change my rate of payroll deduction under the ESPP as
      follows (select one):

      Percentage to be Deducted (circle one) 1%  2%  3%  4%  5%  6%  7%
                                     8%  9%  10%


      An increase or a decrease in payroll deduction will be effective for the
      first full payroll period commencing no fewer than five (5) business days
      following the Company's receipt of this notice, unless this change is
      processed more quickly.

================================================================================


                                      B-1
<PAGE>
================================================================================

[ ] CHANGE OF BENEFICIARY              [ ] I am single          [ ] I am married

      This change of beneficiary shall terminate my previous beneficiary
      designation under the ESPP. In the event of my death, I hereby designate
      the following person or trust as my beneficiary to receive all payments
      and shares due to me under the ESPP:

<TABLE>
<S>                                                                                 <C>
Beneficiary (please print)                                                          Relationship to Beneficiary (if any)
                          ------------------------------------------------------
                                 (Last)            (First)            (MI)

Street Address
               -----------------------------------------------------------------    -------------------------------------


City, State/Country, Zip
                         -------------------------------------------------------
</TABLE>

================================================================================


      Date:                  Employee Signature:
            --------------                      --------------------------------


                                                --------------------------------
                                                spouse's signature (if
                                                beneficiary is other
                                                than spouse)


                                      B-1
<PAGE>
                                    EXHIBIT C

              Dynavax Technologies Corporation 2004 Employee Stock Purchase Plan
                                                         CHANGE OF STATUS NOTICE

                        DURING FIRST PURCHASE PERIOD OF THE INITIAL OFFER PERIOD


--------------------------------------------------------------
Participant Name (Please Print)

--------------------------------------------------------------
Social Security Number

================================================================================

      WITHDRAWAL FROM ESPP

      I hereby withdraw from the Dynavax Technologies Corporation 2004 Employee
      Stock Purchase Plan (the "ESPP") and agree that my option under the
      applicable Offer Period will be automatically terminated. No payroll
      deductions will be made for the purchase of shares in the initial Offer
      Period and I shall be eligible to participate in a future Offer Period
      only by timely delivery to the Company of a new Subscription Agreement.

[ ]   WITHDRAWAL WITHOUT PURCHASE BY DIRECT PAYMENT

      I elect not to purchase shares by direct payment during the first Purchase
      Period of the initial Offer Period.

================================================================================

[ ]   INITIATE PAYROLL DEDUCTION DURING FIRST PURCHASE PERIOD OF INITIAL OFFER
      PERIOD

      I hereby elect to initiate payroll deduction under the ESPP as follows
      (select one):

Percentage to be Deducted (circle one)  1%  2%  3%  4%  5%  6%  7%
                                8%  9%  10%

      To the extent possible, the rate of payroll deduction will exceed the
      percentage indicated to yield the correct amount of withholding on the
      Exercise Date to cover payroll periods during which no withholding for
      participation in the Plan was made.

      I understand that this notice and payroll withholding rate shall remain in
      effect for successive Offer Periods until I withdraw from participation in
      the ESPP, change withholding rates, or the ESPP terminates.

      An increase or a decrease in payroll deduction or direct payment
      percentage will be effective for the first full payroll period commencing
      no fewer than five (5) business days following the Company's receipt of
      this notice, unless this change is processed more quickly.

================================================================================


                                      C-1
<PAGE>
================================================================================

DESIGNATION OF BENEFICIARY

      In the event of my death, I hereby designate the following person or trust
      as my beneficiary to receive all payments and shares due to me under the
      ESPP:    [ ] I am single       [ ] I am married

<TABLE>
<S>                                                                               <C>
Beneficiary (please print)                                                        Relationship to Beneficiary (if any)
                           -----------------------------------------------------
                                 (Last)            (First)              (MI)

Street Address
               -----------------------------------------------------------------  ------------------------------------

City, State/Country, Zip
                         -------------------------------------------------------
</TABLE>

================================================================================


      Date:                  Employee Signature:
            --------------                      --------------------------------


                                                --------------------------------
                                                spouse's signature (if
                                                beneficiary is other
                                                than spouse)


                                      C-1