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                                                                   Exhibit 10.12

                        DYNAVAX TECHNOLOGIES CORPORATION

                         MANAGEMENT CONTINUITY AGREEMENT

       This Management Continuity Agreement (the "AGREEMENT") is dated as of
November 17, 2000 by and between Robert Lee Coffman, Vice President and Chief
Scientific Officer, Dynavax Technologies Corporation ("EMPLOYEE") and Dynavax
Technologies Corporation., a California corporation (the "COMPANY" or
"DYNAVAX").

                                    RECITALS

       A.     It is expected that another company may from time to time consider
the possibility of acquiring the Company or that a change in control may
otherwise occur, with or without the approval of the Company's Board of
Directors. The Board of Directors recognizes that such consideration can be a
distraction to Employee and can cause Employee to consider alternative
employment opportunities. The Board of Directors has determined that it is in
the best interests of the Company to assure that the Company will have the
continued dedication and objectivity of the Employee, notwithstanding the
possibility, threat or occurrence of a Change of Control (as defined below) of
the Company.

       B.     The Company's Board of Directors believes it is in the best
interests of the Company to retain Employee and provide incentives to Employee
to continue in the service of the Company.

       C.     The Board of Directors further believes that it is imperative to
provide Employee with certain benefits upon a Change of Control and, under
certain circumstances, upon termination of Employee's employment in connection
with a Change of Control, which benefits are intended to provide Employee with
encouragement to Employee to remain with the Company, notwithstanding the
possibility of a Change of Control.

       D.     To accomplish the foregoing objectives, the Board of Directors has
directed the Company, upon execution of this Agreement by Employee, to agree to
the terms provided in this Agreement.

       Now therefore, in consideration of the mutual promises, covenants and
agreements contained herein, and in consideration of the continuing employment
of Employee by the Company, the parties hereto agree as follows:

       1.     AT-WILL EMPLOYMENT. The Company and Employee acknowledge that
Employee's employment is and shall continue to be at-will, as defined under
applicable law, and that Employee's employment with the Company may be
terminated by either party at any time for any or no reason. If Employee's
employment terminates for any reason, Employee shall not be entitled to any
payments, benefits, damages, award or compensation other than as provided in
this Agreement, or as may otherwise be available in accordance with the terms of
the Company's established employee plans and written policies at the time of
termination. The terms of this Agreement shall terminate upon the earlier of (i)
the date on which Employee ceases to be

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employed as an executive corporate officer of the Company, other than as a
result of an involuntary termination by the Company without cause (ii) the date
that all obligations of the parties hereunder have been satisfied, or (iii) two
(2) years after a Change of Control. A termination of the terms of this
Agreement pursuant to the preceding sentence shall be effective for all
purposes, except that such termination shall not affect the payment or provision
of compensation or benefits on account of a termination of employment occurring
prior to the termination of the terms of this Agreement. The rights and duties
created by this Section 1 may not be modified in any way except by a written
agreement executed by an officer of the Company upon direction from the Board of
Directors.

       2.     BENEFITS UPON A CHANGE OF CONTROL; TERMINATION OF EMPLOYMENT.

              (a)    TREATMENT OF STOCK OPTIONS UPON A CHANGE OF CONTROL. In the
event of a Change of Control and the Employee (i) is offered and accepts a
position with the New Company, or (ii) is not offered a position as an executive
officer with the New Company, then immediately prior to the time of
effectiveness of the Change of Control an additional two years vesting of
employees stock option to purchase the Company's Common Stock granted to
Employee over the course of his employment with the Company and held by Employee
on the effective date of a Change of Control shall immediately vest on such date
as to that number of shares that would have vested in accordance with the terms
of the 1997 Incentive Plan, as amended.

              (b)    INVOLUNTARY TERMINATION FOLLOWING A CHANGE OF CONTROL. In
the event that Employee's employment is terminated as a result of an Involuntary
Termination other than for Cause at any time within 24 months following the
effective date of a Change of Control, then Employee will be entitled to receive
immediate accelerated vesting pursuant to this Section 2(b), of all stock
options to purchase the Company's Common Stock granted to Employee over the
course of his employment with the Company and held by Employee on the date of
termination of employment.

              (c)    TERMINATION FOR CAUSE. If Employee's employment is
terminated for Cause at any time, then Employee shall not be entitled to receive
payment of any severance benefits. Employee will receive payment(s) for all
salary, bonuses and unpaid vacation accrued as of the date of Employee's
termination of employment and Employee's benefits will be continued under the
Company's then existing benefit plans and policies in accordance with such plans
and policies in effect on the date of termination and in accordance with
applicable law.

              (d)    VOLUNTARY RESIGNATION. If Employee voluntarily resigns from
the Company, then Employee shall not be entitled to receive payment of any
severance benefits. Employee will receive payment(s) for all salary and unpaid
vacation accrued as of the date of Employee's termination of employment and
Employee's benefits will be continued under the Company's then existing benefit
plans and policies in accordance with such plans and policies in effect on the
date of termination and in accordance with applicable law.

       3.     DEFINITION OF TERMS. The following terms referred to in this
Agreement shall have the following meanings:


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              (a)    CHANGE OF CONTROL. "Change of Control" shall mean the
occurrence of any of the following events:

                     (i)    OWNERSHIP. Any "Person" (as such term is used in
Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended) is
or becomes the "Beneficial Owner" (as defined in Rule 13d-3 under said Act),
directly or indirectly, of securities of the Company representing 50% or more of
the total voting power represented by the Company's then outstanding voting
securities WITHOUT the approval of the Board;

                     (ii)   MERGER/SALE OF ASSETS. A merger or consolidation of
the Company whether or not approved by the Board, other than a merger or
consolidation which would result in the voting securities of the Company
outstanding immediately prior thereto continuing to represent (either by
remaining outstanding or by being converted into voting securities of the
surviving entity) at least 50% of the total voting power represented by the
voting securities of the Company or such surviving entity outstanding
immediately after such merger or consolidation, or the stockholders of the
Company approve a plan of complete liquidation of the Company or an agreement
for the sale or disposition by the Company of all or substantially all of the
Company's assets; or

              (b)    CAUSE. "Cause" shall mean (i) gross negligence or willful
misconduct in the performance of Employee's duties to the Company where such
gross negligence or willful misconduct has resulted or is likely to result in
substantial and material damage to the Company or its subsidiaries (ii) repeated
unexplained or unjustified absence from the Company, (iii) a material and
willful violation of any federal or state law; (iv) commission of any act of
fraud with respect to the Company or (v) conviction of a felony or a crime
involving moral turpitude causing material harm to the standing and reputation
of the Company, in each case as determined in good faith by the Board.

              (c)    INVOLUNTARY TERMINATION. "Involuntary Termination" shall
include any termination by the Company other than for Cause and Employee's
voluntary termination following (i) a material reduction or change in job
duties, responsibilities and requirements inconsistent with the Employee's
position with the Company and the Employee's prior duties, responsibilities and
requirements or a change in Employee's reporting relationship; (ii) any
reduction of Employee's base compensation (other than in connection with a
general decrease in base salaries for most officers of the successor
corporation); or (iii) Employee's refusal to relocate to a facility or location
more than 15 miles from the Company's current location.


       4.     CONFLICTS. Employee represents that his performance of all the
terms of this Agreement will not breach any other agreement to which Employee is
a party. Employee has not, and will not during the term of this Agreement, enter
into any oral or written agreement in conflict with any of the provisions of
this Agreement. Employee further represents that he is entering into or has
entered into an employment relationship with the Company of his own free will
and that he has not been solicited as an employee in any way by the Company.


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       5.     SUCCESSORS. Any successor to the Company (whether direct or
indirect and whether by purchase, lease, merger, consolidation, liquidation or
otherwise) to all or substantially all of the Company's business and/or assets
shall assume the obligations under this Agreement and agree expressly to perform
the obligations under this Agreement in the same manner and to the same extent
as the Company would be required to perform such obligations in the absence of a
succession. The terms of this Agreement and all of Employee's rights hereunder
and thereunder shall inure to the benefit of, and be enforceable by, Employee's
personal or legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees.

       6.     NOTICE. Notices and all other communications contemplated by this
Agreement shall be in writing and shall be deemed to have been duly given when
personally delivered or when mailed by U.S. registered or certified mail, return
receipt requested and postage prepaid. Mailed notices to Employee shall be
addressed to Employee at the home address that Employee most recently
communicated to the Company in writing. In the case of the Company, mailed
notices shall be addressed to its corporate headquarters, and all notices shall
be directed to the attention of its Secretary.

       7.     MISCELLANEOUS PROVISIONS.

              (a)    NO DUTY TO MITIGATE. Employee shall not be required to
mitigate the amount of any payment contemplated by this Agreement (whether by
seeking new employment or in any other manner), nor shall any such payment be
reduced by any earnings that Employee may receive from any other source.

              (b)    WAIVER. No provision of this Agreement shall be modified,
waived or discharged unless the modification, waiver or discharge is agreed to
in writing and signed by Employee and by an authorized officer of the Company
(other than Employee). No waiver by either party of any breach of, or of
compliance with, any condition or provision of this Agreement by the other party
shall be considered a waiver of any other condition or provision or of the same
condition or provision at another time.

              (c)    WHOLE AGREEMENT. No agreements, representations or
understandings (whether oral or written and whether expressed or implied) which
are not expressly set forth in this Agreement have been made or entered into by
either party with respect to the subject matter hereof. This Agreement
supersedes any agreement of the same title and concerning similar subject matter
dated prior to the date of this Agreement, and by execution of this Agreement
both parties agree that any such predecessor agreement shall be deemed null and
void.

              (d)    CHOICE OF LAW. The validity, interpretation, construction
and performance of this Agreement shall be governed by the laws of the State of
California without reference to conflict of laws provisions.

              (e)    SEVERABILITY. If any term or provision of this Agreement or
the application thereof to any circumstance shall, in any jurisdiction and to
any extent, be invalid or unenforceable, such term or provision shall be
ineffective as to such jurisdiction to the extent of



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such invalidity or unenforceability without invalidating or rendering
unenforceable the remaining terms and provisions of this Agreement or the
application of such terms and provisions to circumstances other than those as to
which it is held invalid or unenforceable, and a suitable and equitable term or
provision shall be substituted therefore to carry out, insofar as may be valid
and enforceable, the intent and purpose of the invalid or unenforceable term or
provision.

              (f)    ARBITRATION. Any dispute or controversy arising under or in
connection with this Agreement may be settled at the option of either party by
binding arbitration in the County of Alameda, California, in accordance with the
rules of the American Arbitration Association then in effect before a single
arbitrator. The judgment may be entered on the arbitrator's award in any court
having jurisdiction. Punitive damages shall not be awarded.

              (g)    LEGAL FEES AND EXPENSES. The parties shall each bear their
own expenses, legal fees and other fees incurred in connection with this
Agreement, although the arbitrator may award legal fees and expenses in
connection with any arbitration as deemed appropriate.

              (h)    NO ASSIGNMENT OF BENEFITS. The rights of any person to
payments or benefits under this Agreement shall not be made subject to option or
assignment, either by voluntary or involuntary assignment or by operation of
law, including (without limitation) bankruptcy, garnishment, attachment or other
creditor's process, and any action in violation of this Section 11(h) shall be
void.

              (i)    EMPLOYMENT TAXES. All payments made pursuant to this
Agreement will be subject to withholding of applicable income and employment
taxes.

              (j)    ASSIGNMENT BY COMPANY. The Company may assign its rights
under this Agreement to an affiliate, and an affiliate may assign its rights
under this Agreement to another affiliate of the Company or to the Company. In
the case of any such assignment, the term "Company" when used in a section of
this Agreement shall mean the corporation that actually employs the Employee.

              (k)    COUNTERPARTS. This Agreement may be executed in
counterparts, each of which shall be deemed an original, but all of which
together will constitute one and the same instrument.


                            [SIGNATURE PAGE FOLLOWS]



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       The parties have executed this Agreement on the date first written above.

                                       DYNAVAX TECHNOLOGIES CORPORATION


                                       By: /s/ Dino Dina
                                          -------------------------------------
                                       Title: President & CEO
                                             ----------------------------------

                                       Address:  717 Potter Street, Suite 100
                                                 Berkeley, CA  94710




                                       ROBERT LEE COFFMAN


                                       Signature: /s/ Robert Lee Coffman
                                                 ------------------------------

                                       Address:  239 Echo Lane
                                                 Portola Valley, CA  94025






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