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                                                                   EXHIBIT 10.22


                            INDEMNIFICATION AGREEMENT

     This Indemnification Agreement ("Agreement") is made as of this ___ day
of___________, 199__ by and between PharmChem Laboratories, Inc., a California
corporation (the "Company"), and _________________ ("Indemnitee").

     WHEREAS, it is essential to the Company to retain and attract as directors
and officers the most capable persons available; and

     WHEREAS, Indemnitee is a [director] [officer] [director and officer] [key
employee] of the Company, and both the Company and Indemnitee recognize the risk
of litigation and other claims being asserted against such person; and

     WHEREAS, in recognition of Indemnitee's need for substantial protection
against personal liability and to enhance Indemnitee's continued and effective
service to the Company, the Company desires to provide for the indemnification
of, and the advancing of expenses to, Indemnitee to the fullest extent permitted
by law subject to the terms set forth in this Agreement.

     NOW, THEREFORE, the Company and Indemnitee hereby agree as follows:

     1.   INDEMNIFICATION.

          (a)  Third Party Proceedings. The Company shall indemnify Indemnitee
if Indemnitee is or was a party or is threatened to be made a party to any
threatened, pending or completed action or proceeding, whether civil, criminal,
administrative or investigative (a "proceeding") (other than an action by or in
the right of the Company to procure a judgment in its favor) by reason of the
fact that Indemnitee is or was a director, officer, employee or agent of the
Company, or any subsidiary of the Company, by reason of any action or inaction
on the part of Indemnitee while an officer or director or by reason of the fact
that Indemnitee is or was serving at the request of the Company as a director,
officer, employee or agent of another corporation, partnership, joint venture,
trust or other enterprise, against expenses (including attorneys' fees and any
federal, state, local or foreign tax imposed on Indemnitee as a result of the
actual or deemed receipt of any payments under this Agreement), judgments, fines
and amounts paid in settlement (if such settlement is approved in advance by the
Company, which approval shall not be unreasonably withheld) actually and
reasonably incurred by Indemnitee in connection with proceeding if Indemnitee
acted in good faith and in a manner Indemnitee reasonably believed to be in the
best interests of the Company, and, with respect to any criminal Proceeding, had
no reasonable cause to believe Indemnitee's conduct was unlawful. The
termination of any Proceeding by judgment, order, settlement, conviction, or
upon a plea of nolo contendere or its equivalent, shall not, of itself, create a
presumption that (i) Indemnitee did not act in good faith and in a manner which
Indemnitee reasonably believed to be in the best interests of the Company, or
(ii) with respect to any criminal Proceeding, Indemnitee had reasonable cause to
believe that Indemnitee's conduct was unlawful.

          (b)  Proceedings By or in the Right of the Company. The Company shall
indemnify Indemnitee if Indemnitee was or is a party or is threatened to be made
a party to any threatened, pending or completed Proceeding by or in the right of
the Company or any subsidiary of the Company to procure a judgment in its favor
by reason of the fact that Indemnitee is or was a director, officer, employee or
agent of the Company, or any subsidiary of the Company, by reason of any action
or inaction on the part of Indemnitee while an officer or director or by reason
of the fact that Indemnitee is or was serving at the request of the Company as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise, against expenses (including attorneys' fees)
and, to the fullest extent permitted by law, amounts paid in settlement, in each
case to the extent actually and reasonably incurred by Indemnitee in connection
with the defense or settlement of such Proceeding if Indemnitee acted in good
faith and in a manner Indemnitee reasonably believed to be in the best interests
of the Company and its shareholders, except that no indemnification shall be
made (i) in respect of any claim, issue or matter

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as to which Indemnitee shall have been adjudged to be liable to the Company in
the performance of Indemnitee's duty to the Company and its shareholders unless
and only to the extent that the court in which such Proceeding is or was pending
shall determine upon application that, in view of all the circumstances of the
case, Indemnitee is fairly and reasonably entitled to indemnity for expenses and
then only to the extent that the court shall determine and (ii) of amounts paid
in settling or otherwise disposing of a pending action without court approval.

     2.   INDEMNIFICATION PROCEDURE.

          (a)  Notice/Cooperation by Indemnitee. Indemnitee shall give the
Company notice in writing as soon as practicable of any claim made against
Indemnitee for which indemnification will or could be sought under this
Agreement. Notice to the Company shall be directed to the Chief Executive
Officer of the Company at the address shown on the signature page of this
Agreement (or such other address as the Company shall designate in writing to
Indemnitee). In addition, Indemnitee shall give the Company such information and
cooperation as it may reasonably require and as shall be within Indemnitee's
power.

          (b)  Procedure. Any indemnification provided for in Section 1 shall be
made no later than forty-five (45) days after receipt of the written request of
Indemnitee. If a claim under this Agreement, under any statute, or under any
provision of the Company's Articles of Incorporation or Bylaws providing for
indemnification, is not paid in full by the Company within forty-five (45) days
after a written request for payment thereof has first been received by the
Company, Indemnitee may, but need not, at any time thereafter bring an action
against the Company to recover the unpaid amount of the claim and, subject to
Section 14 of this Agreement, Indemnitee shall also be entitled to be paid for
the expenses (including attorneys' fees) of bringing such action. It shall be a
defense to any such action (other than an action brought to enforce a claim for
expenses incurred in connection with any action or proceeding in advance of its
final disposition) that Indemnitee has not met the standards of conduct which
make it permissible under applicable law for the Company to indemnify Indemnitee
for the amount claimed, but the burden of proving such defense shall be on the
Company. It is the parties' intention that if the Company contests Indemnitee's
right to indemnification, the question of Indemnitee's right to indemnification
shall be for the court to decide, and neither the failure of the Company
(including its Board of Directors, any committee or subgroup of the Board of
Directors, independent legal counsel, or its shareholders) to have made a
determination that indemnification of Indemnitee is proper in the circumstances
because Indemnitee has met the applicable standard of conduct required by
applicable law, nor an actual determination by the Company (including its Board
of Directors, any committee or subgroup of the Board of Directors, independent
legal counsel, or its shareholders) that Indemnitee has not met such applicable
standard of conduct, shall create a presumption that Indemnitee has or has not
met the applicable standard of conduct.

          (c)  Notice to Insurers. If, at the time of the receipt of a notice of
a claim pursuant to Section 2(a) hereof, the Company has director and officer
liability insurance in effect, the Company shall give prompt notice of the
commencement of such proceeding to the insurers in accordance with the
procedures set forth in the respective policies. The Company shall thereafter
take all necessary or desirable action to cause such insurers to pay, on behalf
of the Indemnitee, all amounts payable as a result of such proceeding in
accordance with the terms of such policies.

          (d)  Selection of Counsel. In the event the Company shall be obligated
under Section 2(a) hereof to pay the expenses of any proceeding against
Indemnitee, the Company, if appropriate, shall be entitled to assume the defense
of such proceeding, with counsel approved by Indemnitee, which approval shall
not be unreasonably withheld, upon the delivery to Indemnitee of written notice
of its election so to do. After delivery of such notice, approval of such
counsel by Indemnitee and the retention of such counsel by the Company, the
Company will not be liable to Indemnitee under this Agreement for any fees of
counsel subsequently incurred by Indemnitee with respect to the same proceeding,
provided 

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that (i) Indemnitee shall have the right to employ counsel in any such
proceeding at Indemnitee's expense; and (ii) if (A) the employment of counsel by
Indemnitee has been previously authorized by the Company, (B) the counsel
retained by the Company shall have reasonably concluded that there may be a
conflict of interest between the Company and Indemnitee in the conduct of any
such defense or (C) the Company shall not, in fact, have employed counsel to
assume the defense of such proceeding, then the fees and expenses of
Indemnitee's counsel shall be at the expense of the Company.

          (e)  Subrogation. To the extent of any payment under this Agreement,
the Company shall be subrogated to all of the rights of recovery of Indemnitee,
who shall execute all documents required and shall do everything that may be
reasonably necessary to secure such rights, including execution of such
documents as are necessary to enable the Company to bring suit to enforce such
rights.

     3.   CHANGE OF CONTROL. This Section 3 shall only apply if a Change of
Control (as hereinafter defined) has occurred.

          (a)  Advance of Expenses in the Event of a Change of Control. In the
event of a Change of Control, expenses, including attorneys' fees, incurred by
Indemnitee in defending or otherwise being involved in a Proceeding shall be
paid by the Company in advance of the final disposition of such Proceeding,
including any appeal therefrom, upon receipt of an undertaking (the
"UNDERTAKING") by or on behalf of Indemnitee to repay such amount if it shall
ultimately be determined that Indemnitee is not entitled to be indemnified by
the Company; provided, that in connection with a Proceeding (or part thereof)
initiated by Indemnitee, except as provided in Section 3(b), the Company shall
pay such expenses in advance of the final disposition only if such Proceeding
(or part thereof) was authorized by the Board of Directors of the Company. Any
Indemnitee to whom expenses are advanced pursuant hereto shall not be obligated
to repay pursuant to the Undertaking until the final determination of any
pending Proceeding in a court of competent jurisdiction concerning the right of
Indemnitee to be indemnified or the obligation of Indemnitee to repay pursuant
to the Undertaking.

          In the event the Company shall be obligated under this Section 3 to
pay the expenses of any Proceeding involving Indemnitee, the Company, if
appropriate, shall be entitled to assume the defense of such Proceeding, with
counsel approved by Indemnitee, which approval shall not be unreasonably
withheld, upon the delivery to Indemnitee of written notice of its election to
do so. After delivery of such notice, approval of such counsel by Indemnitee and
the retention of such counsel by the Company, the Company will not be liable to
Indemnitee under this Agreement for any fees of counsel subsequently incurred by
Indemnitee with respect to the same Proceeding, provided that (i) Indemnitee
shall have the right to employ counsel in any such Proceeding at Indemnitee's
expense; and (ii) if (A) the employment of counsel by Indemnitee has been
previously authorized by the Company, (B) the counsel retained by the Company
shall have reasonably concluded that there may be a conflict of interest between
the Company and Indemnitee in the conduct of any such defense or (C) the Company
shall not, in fact, have employed counsel to assume the defense of such
Proceeding, then the fees and expenses of Indemnitee's counsel shall be at the
expense of the Company.

          (b)  If a Change of Control has occurred, Indemnitee upon making a
claim under Section 1 or seeking to avoid repayment to the Company pursuant to
the undertaking under Section 2(a) shall have (i) the right, but not the
obligation, to have a determination made by independent legal counsel as to
whether indemnification of Indemnitee is proper because Indemnitee has met the
applicable standard of conduct required under the California General Corporation
Law; and (ii) shall have the right to select as independent legal counsel for
such purpose any law firm as designated (or within a category designated) for
such purpose in a resolution adopted by the Board of Directors of the Company
prior to the Change of Control and in full force and effect immediately prior to
the Change of Control. If a determination has been made in accordance with the
preceding sentence, no determination inconsistent therewith by other legal
counsel, by the Board of Directors or by stockholders shall be of any force or

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effect, provided that Indemnitee shall maintain all rights granted hereby to
bring an action as specified in Section 2(b).

     "Change of Control" means any one or more of the following:

               (i)  the acquisition or holding by any person, entity or "group"
(within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities and
Exchange Act of 1934 [the "1934 Act"], other than by the Company or any
subsidiary or any employee benefit plan of the Company or a subsidiary, of
beneficial ownership (within the meaning of Rule 13d-3 under the 1934 Act) of
20% or more of the then-outstanding common stock or the then-outstanding voting
power of the Company; provided, however, that no Change of Control shall occur
solely by reason of any such acquisition by a corporation with respect to which,
after such acquisition, more than 60% of both the then-outstanding common shares
and the then-outstanding voting power of such corporation are then-beneficially
owned, directly or indirectly, by the persons who were the beneficial owners of
the common stock of the Company immediately before such acquisition, in
substantially the same proportions as their respective ownership, immediately
before such acquisition, of the then-outstanding common stock and voting power
of the Company; or

               (ii) individuals who, as of the effective date of this Agreement,
constitute the Board of Directors of the Company (the "Incumbent Board") cease
for any reason to constitute at least a majority of the Board of Directors;
provided that any individual who becomes a director after the effective date of
this Agreement whose election or nomination for election by the Company's
shareholders was approved by at least a majority of the Incumbent Board (other
than an election or nomination of an individual whose initial assumption of
office is in connection with an actual or threatened election contest relating
to the election of the directors of the Company (as such terms are used in Rule
14a-11 under the 1934 Act)) shall be deemed to be a member of the Incumbent
Board; or

               (iii) approval by the shareholders of the Company of any one or
more of the following:

               (A)  a merger, reorganization or consolidation (an "Extraordinary
Transaction") with respect to which persons who were the respective beneficial
owners of the common stock of the Company immediately before such Extraordinary
Transaction would not, if such Extraordinary Transaction were to be consummated
immediately after such shareholder approval (but otherwise in accordance with
the terms presented in writing to the shareholders of the Company for their
approval), beneficially own, directly or indirectly, more than 60% of both the
then-outstanding common shares and the then-outstanding voting power of the
corporation resulting from such Extraordinary Transaction, in substantially the
same proportions as their respective ownership, immediately before such
Extraordinary Transaction, of the then-outstanding common stock and voting power
of the Company,

               (B)  a liquidation or dissolution of the Company, or

               (C)  the sale or other disposition of all or substantially all of
the assets of the Company in one transaction or a series of related
transactions.

     Notwithstanding the foregoing, a Change of Control shall not occur with
respect to any Indemnitee who, by agreement or understanding (written or
otherwise), participates on such Indemnitee's own behalf in a transaction which
causes the Change of Control to occur.

     4.   ADDITIONAL INDEMNIFICATION RIGHTS: NONEXCLUSIVITY.

          (a)  Scope. Notwithstanding any other provision of this Agreement, the
Company hereby agrees to indemnify the Indemnitee to the fullest extent
permitted by law, notwithstanding that such indemnification is not specifically
authorized by the other provisions of this Agreement, the Company's Articles of
Incorporation, the Company's Bylaws or by statute. In the event of any change,

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after the date of this Agreement, in any applicable law, statute or rule which
expands the right of a California corporation to indemnify a member of its board
of directors or an officer, such changes shall be, ipso facto, within the
purview of Indemnitee's rights and Company's obligations, under this Agreement.
In the event of any change in any applicable law, statute or rule which narrows
the right of a California corporation to indemnify a member of its Board of
Directors or an officer, such changes, to the extent not otherwise required by
such law, statute or rule to be applied to this Agreement shall have no effect
on this Agreement or the parties' rights and obligations hereunder.

          (b)  Nonexclusivity. The indemnification provided by this Agreement
shall not be deemed exclusive of any rights to which Indemnitee may be entitled
under the Company's Articles of Incorporation, its Bylaws, any agreement, any
vote of shareholders or disinterested directors, the California General
Corporation Law, or otherwise, both as to action in Indemnitee's official
capacity and as to action in another capacity while holding such office. The
indemnification provided under this Agreement shall continue as to Indemnitee
for any action taken or not taken while serving in an indemnified capacity even
though Indemnitee may have ceased to serve in such capacity at the time of any
action or other covered proceeding.

     5.   PARTIAL INDEMNIFICATION. If Indemnitee is entitled under any provision
of this Agreement to indemnification by the Company for some or a portion of the
expenses, judgments, fines or penalties actually or reasonably incurred by
Indemnitee in the investigation, defense, appeal or settlement of any civil or
criminal action or proceeding, but not, however, for the total amount thereof,
the Company shall nevertheless indemnify Indemnitee for the portion of such
expenses, judgments, fines or penalties to which Indemnitee is entitled.

     6.   MUTUAL ACKNOWLEDGEMENT. Both the Company and Indemnitee acknowledge
that in certain instances, Federal law or applicable public policy may prohibit
the Company from indemnifying its directors and officers under this Agreement or
otherwise. Indemnitee understands and acknowledges that the Company has
undertaken or may be required in the future to undertake with the Securities and
Exchange Commission to submit the question of indemnification to a court in
certain circumstances for a determination of the Company's right under public
policy to indemnify Indemnitee.

     7.   DIRECTORS' AND OFFICERS' LIABILITY INSURANCE. The Company shall, from
time to time, make the good faith determination whether or not it is practicable
for the Company to obtain and maintain a policy or policies of insurance with
reputable insurance companies providing the officers and directors of the
Company with coverage for losses from wrongful acts, or to ensure the Company's
performance of its indemnification obligations under this Agreement. Among other
considerations, the Company will weigh the costs of obtaining such insurance
coverage against the protection afforded by such coverage. In all policies of
directors' and officers' liability insurance, if Indemnitee is a director or
officer of the Company, Indemnitee shall be named as an insured in such a manner
as to provide Indemnitee the same rights and benefits as are accorded to the
most favorably insured of the Company's directors, if Indemnitee is a director;
or of the Company's officers, if Indemnitee is not a director of the Company but
is an officer. Notwithstanding the foregoing, the Company shall have no
obligation to obtain or maintain such insurance if the Company determines in
good faith that such insurance is not reasonably available, if the premium costs
for such insurance are disproportionate to the amount of coverage provided, if
the coverage provided by such insurance is limited by exclusions so as to
provide an insufficient benefit, or if Indemnitee is covered by similar
insurance maintained by a subsidiary or parent of the Company.

     8.   SEVERABILITY. Nothing in this Agreement is intended to require or
shall be construed as requiring the Company to do or fail to do any act in
violation of applicable law. The Company's inability, pursuant to court order,
to perform its obligations under this Agreement shall not constitute a breach of
this Agreement. The provisions of this Agreement shall be severable as provided
in this Section 8. If this Agreement or any portion hereof shall be invalidated
on any ground by any court of competent jurisdiction, then the Company shall
nevertheless indemnify Indemnitee to the full extent permitted by any

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applicable portion of this Agreement that shall not have been invalidated, and
the balance of this Agreement not so invalidated shall be enforceable in
accordance with its terms.

     9.   EXCEPTIONS. Any other provision herein to the contrary
notwithstanding, the Company shall not be obligated pursuant to the terms of
this Agreement:

          (a)  Excluded Acts. To indemnify Indemnitee for any acts or omissions
or transactions from which a director may not be relieved of liability under the
California General Corporation Law; or

          (b)  Claims Initiated by Indemnitee. To indemnify or advance expenses
to Indemnitee with respect to proceedings or claims initiated or brought
voluntarily by Indemnitee and not by way of defense, except with respect to
proceedings brought to establish or enforce a right to indemnification under
this Agreement or any other statute or law or otherwise as required under
Section 317 of the California General Corporation Law, but such indemnification
or advancement of expenses may be provided by the Company in specific cases if
the Board of Directors has approved the initiation or bringing of such suit; or

          (c)  Lack of Good Faith. To indemnify Indemnitee for any expenses
incurred by the Indemnitee with respect to any proceeding instituted by
Indemnitee to enforce or interpret this Agreement, if a court of competent
jurisdiction determines that each of the material assertions made by the
Indemnitee in such proceeding was not made in good faith or was frivolous; or

          (d)  No Duplication of Payments. To indemnify Indemnitee for expenses
or liabilities of any type whatsoever to the extent the Indemnitee has otherwise
actually received payment under any insurance policy, the Company's Articles of
Incorporation, or Bylaws, other agreements with the Indemnitee for
indemnification, vote of the shareholders or directors or otherwise of the
amounts otherwise indemnifiable; or

          (e)  Claims Under Section 16(b). To indemnify Indemnitee for expenses
and the payment of profits arising from the purchase and sale by Indemnitee of
securities in violation of Section 16(b) of the Securities Exchange Act of 1934,
as amended, or any similar successor statute.

     10.  EFFECTIVENESS OF AGREEMENT. This Agreement shall be effective as of
the date set forth on the first page and shall apply to acts or omissions of
Indemnitee which occurred prior to such date if Indemnitee was an officer,
director, employee or other agent of the Company, or was serving at the request
of the Company as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, at the time such act or
omission occurred.

     11.  CONSTRUCTION OF CERTAIN PHRASES.

          (a)  For purposes of this Agreement, references to the "Company" shall
include, in addition to the resulting corporation, any constituent corporation
(including any constituent of a constituent) absorbed in a consolidation or
merger which, if its separate existence had continued, would have had power and
authority to indemnify its directors, officers, employees or agents, so that if
Indemnitee is or was a director, officer, employee or agent of such constituent
corporation, or is or was serving at the request of such constituent corporation
as a director, officer, employee or agent of another corporation, partnership,
joint venture, trust or other enterprise, Indemnitee shall stand in the same
position under the provisions of this Agreement with respect to the resulting or
surviving corporation as Indemnitee would have with respect to such constituent
corporation if its separate existence had continued.

          (b)  For purposes of this Agreement, references to "other enterprises"
shall include employee benefit plans; references to "fines" shall include any
excise taxes assessed on Indemnitee with

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respect to an employee benefit plan; and references to "serving at the request
of the Company" shall include any service as a director, officer, employee or
agent of the Company which imposes duties on, or involves services by, such
director, officer, employee or agent with respect to an employee benefit plan,
its participants or beneficiaries.

     12.  COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall constitute an original.

     13.  SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon, and
shall inure to the benefit of, the parties hereto and their respective spouses,
heirs, legal representatives, successors and assigns (including, without
limitation, any successor by purchase, merger, consolidation, reorganization or
otherwise to all or substantially all of the business and/or assets of the
Company).

     14.  ATTORNEYS' FEES. In the event that any action is instituted by
Indemnitee under this Agreement to enforce or interpret any of the terms hereof,
Indemnitee shall be entitled to be paid all court costs and expenses, including
reasonable attorneys' fees, incurred by Indemnitee with respect to such action,
unless as a part of such action, the court of competent jurisdiction determines
that each of the material assertions made by Indemnitee as a basis for such
action were not made in good faith or were frivolous. In the event of an action
instituted by or in the name of the Company under this Agreement or to enforce
or interpret any of the terms of this Agreement, Indemnitee shall be entitled to
be paid all court costs and expenses, including attorneys' fees, incurred by
Indemnitee in defense of such action (including with respect to Indemnitee's
counterclaims and cross-claims made in such action), unless as a part of such
action the court determines that each of Indemnitee's material defenses to such
action were made in bad faith or were frivolous.

     15.  NOTICE. All notices, requests, demands and other communications under
this Agreement shall be in writing and shall be deemed duly given (i) if mailed
by domestic certified or registered mail with postage prepaid, on the third
business day after the date postmarked or (ii) if sent by any other method, on
the date such notice is actually received. Addresses for notice to either party
are as shown on the signature page of this Agreement, or as subsequently
modified by written notice.

     16.  CONSENT TO JURISDICTION. The Company and Indemnitee each hereby
irrevocably consent to the jurisdiction of the courts of the State of California
for all purposes in connection with any action or proceeding which arises out of
or relates to this Agreement and agree that any action instituted under this
Agreement shall be brought only in the state courts of the State of California.

     17.  CHOICE OF LAW. This Agreement shall be governed by and its provisions
construed in accordance with the laws of the State of California as applied to
contracts between California residents entered into and to be performed entirely
within California.

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     18.  AMENDMENT; WAIVER. No provision of this Agreement may be amended or
modified except with the consent in writing of the Indemnitee and the Company,
nor may any provision of this Agreement be waived except in writing by the party
granting such waiver. A waiver of any provision hereof shall not be deemed a
waiver of any other provision hereof. Failure of either of the parties hereto to
insist upon strict compliance with any provision hereof shall not be deemed to
be a waiver of such provision or any other provision hereof.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date first above written.

                                       PHARMCHEM LABORATORIES, INC.

                                       By:
                                           -------------------------------------
                                       Title: 
                                              ----------------------------------

                                       Address:    1505-A O'Brien Drive
                                                   Menlo Park, CA  94025

                                                   Telephone: (650) 328-6200

AGREED TO AND ACCEPTED:

INDEMNITEE:


Name: 
      --------------------------------
Address: 
         -----------------------------
Date: 
      --------------------------------


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