RECORDING REQUESTED BY
AND WHEN RECORDED MAIL TO:

Cassidy, Cheatham, Shimko & Dawson, P.C.
20 California Street, Suite 500
San Francisco, CA 94111

Attention:  Stephen K. Cassidy, Esq.

                                        SPACE ABOVE THIS LINE FOR RECORDER'S USE


                  DEED OF TRUST, SECURITY AGREEMENT AND FIXTURE
                  FILING WITH ASSIGNMENT OF RENTS AND PROCEEDS

THIS DEED OF TRUST,  SECURITY  AGREEMENT AND FIXTURE  FILING WITH  ASSIGNMENT OF
RENTS AND PROCEEDS  (the "Deed of Trust"),  dated as of September  22, 1998,  is
made and  delivered  by  MISSION  WEST  PROPERTIES,  L.P.,  a  Delaware  limited
partnership,  MISSION WEST PROPERTIES,  L.P. I, a Delaware limited  partnership,
MISSION WEST PROPERTIES,  L.P. II, a Delaware limited  partnership,  and MISSION
WEST PROPERTIES,  L.P. III, a Delaware limited partnership,  each having offices
at 10050  Bandley  Drive,  Cupertino,  California  95014 (each,  a "Trustor" and
collectively,  "Trustors";  reference herein to a "Trustor"  meaning each of the
Trustors, unless the specific reference otherwise specifies), to Financial Title
Company,  having  offices  at 701  Miller  Street,  San Jose,  California  95110
("Trustee"),  and THE  PRUDENTIAL  INSURANCE  COMPANY OF  AMERICA,  a New Jersey
corporation,  having  offices  at  Four  Embarcadero  Center,  Suite  2700,  San
Francisco, California 94111 ("Beneficiary").

                                   WITNESSETH:

TRUSTOR HEREBY IRREVOCABLY  GRANTS,  TRANSFERS AND ASSIGNS TO TRUSTEE, IN TRUST,
WITH  POWER OF SALE all of  Trustor's  right,  title and  interest  now owned or
hereafter  acquired  in  and  to  the  following  property,  together  with  the
Personalty (as hereinafter defined):

A.  That  certain  real  property,  and all  rights  and  appurtenances  thereto
(collectively,  the "Land"),  located in the Counties of Alameda and Santa Clara
State of California, and more particularly described in EXHIBIT A hereto;

B. All Improvements (as hereinafter  defined) and all appurtenances,  easements,
rights and  privileges  thereof,  including  all  minerals,  oil,  gas and other
hydrocarbon  substances  thereon  or  therein,  air  rights,  water  rights  and
development  rights,  and any  land  lying  in the  streets,  roads  or  avenues
adjoining the Land or any part thereof;

C. All Fixtures (as hereinafter  defined),  whether now or hereafter  installed,
being hereby declared to be for all purposes of this Deed of Trust a part of the
Land; and

D. All Rents and Proceeds (as hereinafter defined).

FOR THE  PURPOSE OF  SECURING,  in such order of  priority  as  Beneficiary  may
determine:  (i) payment of the Indebtedness (as hereinafter  defined);  and (ii)
payment  (with  interest as provided) and  performance  by Trustors of the other
Obligations  (as hereinafter  defined).  Notwithstanding  the foregoing,  or any
other  term  contained  herein  or in the  Loan  Documents,  none  of  Trustors'
Obligations  under or pursuant to the (A) Hazardous  Substances  Remediation and
Indemnification  Agreement or (B)  Certificate  Regarding  Distribution  of Loan
Proceeds  and  Indemnity  Agreement,  each of even date  herewith,  executed  by
Trustors in favor of Beneficiary  ("Hazardous  Substances  Agreement")  shall be
secured by the lien of this Deed of Trust.

                                    ARTICLE 1
                                   DEFINITIONS

CERTAIN DEFINED TERMS: As used in this Deed of Trust,  the following terms shall
have the following  meanings.  Terms defined in the other Loan  Documents  shall
have the same meaning when used herein.

AGREEMENTS:  As defined in PARAGRAPH 8.2 hereof.

APPLICATION:  The  Application,  dated  June  24,  1998,  executed  by  Trustors
(referred to as "Applicant"  therein),  which Application  includes the mortgage
loan conditions attached thereto.

ASSIGNMENT OF LEASES: The Assignment of Lessor's Interest in Leases of even date
herewith executed by Trustors in favor of Beneficiary.

CERTIFICATE REGARDING DISTRIBUTION OF LOAN PROCEEDS AND INDEMNITY AGREEMENT: The
Certificate  Regarding  Distribution of Loan Proceeds and Indemnity Agreement of
even date herewith executed by Trustors in favor of Beneficiary.

COLLATERAL:  As defined in PARAGRAPH 7.1 hereof.

DEBT SERVICE COVERAGE RATIO: The ratio, as reasonably determined by Beneficiary,
derived by dividing (a) Net Operating Income for the Property for the applicable
twelve (12) month period, by (b) the sum of (i) the annual debt service payments
(including  principal and interest) on the Loan for such  12-month  period,  and
(ii) the annual debt service payments (including  principal and interest) on all
other  indebtedness  secured,  or to be  secured  in due  course,  by a lien  or
encumbrance on all or part of the Property for such 12-month period.

ELIGIBLE TRANSFER PROPERTY:  As defined in PARAGRAPH 4.3 hereof.

ERISA:  As defined in PARAGRAPH 9.18.B hereof.

EVENT OF DEFAULT:  As defined in PARAGRAPH 6.1 hereof.

FIXTURES:  All  fixtures  located  upon or  within  the  Improvements  or now or
hereafter  installed  in, or used in  connection  with any of the  Improvements,
whether or not permanently affixed to the Land or the Improvements.

HAZARDOUS  SUBSTANCES  AGREEMENT:  As defined in the above Securing paragraph of
this Deed of Trust.

IMPOSITIONS:  All  real  estate  and  personal  property  and  other  taxes  and
assessments,  and  any  and  all  other  charges,  expenses,  payments,  claims,
mechanics' or material suppliers' liens or assessments of any nature that at any
time prior to or after the  execution  of the Loan  Documents  may be  assessed,
levied,  imposed,  or  become a lien  upon the  Property  or the rent or  income
received therefrom, or any use or occupancy thereof.

IMPOUND ACCOUNT:  The account that Trustor shall maintain when required pursuant
to PARAGRAPH 3.4 hereof.

IMPROVEMENTS:  All buildings and other improvements located on the
Land, or at any time hereafter constructed or placed upon the
Land, and all additions to, modifications of and replacements
thereof.

INDEBTEDNESS:  The indebtedness  evidenced by the Note (including any prepayment
charges due  thereunder)  and all other amounts due from Trustor to  Beneficiary
evidenced or secured by the Loan Documents, plus interest on all such amounts as
provided in the Loan Documents.

LAND: As defined in the above Granting Paragraph A of this Deed of Trust.

LAND USE  CERTIFICATION:  The  Land  Use  Certification  of even  date  herewith
executed by Trustors in favor of Beneficiary.

LAWS AND RESTRICTIONS: All laws, regulations,  orders, codes, ordinances, rules,
statutes  and  policies,  restrictive  covenants  and other title  encumbrances,
permits  and  approvals,   Leases,  relating  to  the  development,   occupancy,
ownership,  management,  use,  and/or  operation  of the  Property or  otherwise
affecting the Property or Trustor.

LEASES: Any and all leasehold interests,  and other rental agreements,  licenses
and  concessions,  now or  hereafter  affecting  or  covering  any  part  of the
Property.

LOAN:  The loan from Beneficiary to Trustors evidenced by the Note.

LOAN DOCUMENTS: The Note, this Deed of Trust, the Application, the Assignment of
Leases, the Land Use  Certification,  the Post Closing Actions Agreement and all
other  documents,   other  than  the  Hazardous  Substances  Agreement  and  the
Certificate  Regarding  Distribution  of Loan Proceeds and Indemnity  Agreement,
evidencing, securing or relating to the Loan, the payment of the Indebtedness or
the performance of the Obligations.

LOAN PARTIES:  Any Trustor, and/or Mission West.

LOAN TO VALUE RATIO: The ratio, as reasonably determined by Beneficiary, derived
by dividing (i) the aggregate outstanding  principal balance,  together with all
accrued but unpaid interest,  of the Loan and all other indebtedness  secured or
to be  secured  in due  course  by a lien or  encumbrance  on all or part of the
Property,  by  (ii)  the  fair  market  value  of the  Property,  as  reasonably
determined by Beneficiary.

MAJOR  LEASES:  The  Leases  with the Major  Tenants.  If  Beneficiary  receives
satisfactory evidence that the Debt Service Coverage Ratio for the preceding six
month  period is at least 1.50 to 1.00,  then any other Lease  covering at least
130,000  rentable square feet, or if Beneficiary  does not receive  satisfactory
evidence that such minimum Debt Service  Coverage  Ratio is satisfied,  then any
Lease  covering at least 65,000  rentable  square feet shall be a "Major Lease."
Reference  to a "Major  Lease"  shall refer to any or all of the Major Leases as
the context may require.

MAJOR  TENANTS:   Apple  Computer  Inc.,  a  California   corporation;   Intevac
Corporation, a California corporation;  Cisco Systems, a California corporation;
ESL  Incorporated,  a California  corporation;  Amdahl  Corporation,  a Delaware
corporation; and On-Command Corporation, a Delaware corporation.  Reference to a
"Major Tenant" shall refer to any or all of the Major Tenants as the context may
require.

MATERIAL  ADVERSE  CHANGE:  Any material and adverse change in (i) the financial
condition of the Loan Parties which,  taken as a whole,  would materially impair
the  ability of the Loan  Parties to perform  their  Obligations  under the Loan
Documents, or (ii) the condition, management or operation of the Property.

MISSION WEST: Mission West Properties,  a California  corporation,  the managing
general  partner of each  Trustor,  or,  following a merger which  satisfies the
provisions of Paragraph 4.2.B(vi) hereof, MWP, Inc.

MISSION WEST MERGER TRANSACTION: As defined in PARAGRAPH 4.2.B hereof.

MWP, INC.:  Mission West Properties, Inc., a Maryland corporation.

NET OPERATING INCOME:  For any period,  (i) gross income derived from operations
of  the  Property  in  the  ordinary   course  from  arm's  length  Leases  with
unaffiliated  third  parties,  including  rent,  service  fees or  charges,  and
additional rent resulting from operating  expense,  common area  maintenance and
tax  escalation  pass through  provisions  (but excluding  extraordinary  income
derived  from the sale of assets  and other  items of income  which  Beneficiary
reasonably determines are unlikely to occur in any subsequent period), (ii) less
operating  expenses of the  Property  incurred in the  ordinary  course (such as
cleaning,  utilities,  administrative,   landscaping,  security  and  management
expenses,  repairs and maintenance and reserves for  replacements) and recurring
fixed  expenses in the ordinary  course (such as ground  rent,  insurance,  real
estate and other taxes and  assessments),  assuming,  for each of the  foregoing
categories of expenses, for any period during which ninety-five percent (95%) of
the net rentable area of any of the  Improvements is not leased and occupied,  a
ninety-five  percent  (95%)  occupancy  level for such  Improvements.  Operating
expenses and fixed  expenses  under clause (ii) above shall exclude all expenses
for capital  improvements  and  replacements,  debt service and  depreciation or
amortization  and  other  similar  noncash  items,  and such  other  amounts  as
Beneficiary  reasonably determines are unlikely to recur in a subsequent period.
Gross  income  shall not be accrued for any greater  period than that allowed by
generally accepted accounting principles and approved by Beneficiary,  nor shall
operating expenses be included to the extent prepaid.

NET PROCEEDS:  As defined in PARAGRAPH 5.1.B hereof.

NOTE:  The  Promissory  Note of even date  herewith  executed by Trustors in the
original    principal   amount   of   One   Hundred   Thirty   Million   Dollars
($130,000,000.00),  payable to Beneficiary or its order, and all  modifications,
renewals or extensions thereof.

OBLIGATIONS: Any and all of the terms, covenants, promises and other obligations
(including  payment of the  Indebtedness)  made or owing by Trustor to or due to
Beneficiary as provided in the Loan Documents and all of the material covenants,
promises  and other  obligations  made or owing by Trustor  to any other  Person
relating to the Property.

OPERATING  PARTNERSHIP  UNITS:  Each  Trustor's  "L.P.  Units,"  as such term is
defined in each Trustor's Amended and Restated Agreement of Limited  Partnership
dated July 1, 1998.

ORIGINAL ALLOCATED LOAN AMOUNT: As defined in PARAGRAPH 4.3 hereof.

PERMITTED  EXCEPTIONS:  All of those  title  exceptions  set  forth in the title
insurance  policy  issued to  Beneficiary  in  connection  with the Loan,  which
insures the priority of this Deed of Trust.

PERSON:  Any  natural  person,  corporation,   firm,  association,   government,
governmental  agency  or any other  entity,  whether  acting  in an  individual,
fiduciary or other capacity.

PERSONALTY:  Trustor's right, title and interest in all personal property (other
than  Fixtures) now or hereafter  located in, upon or about or collected or used
in  connection  with  the  Property,   together  with  all  present  and  future
attachments,  accessions,  replacements,  substitutions and additions thereto or
therefor,  and the cash and  noncash  proceeds  thereof,  including  all  goods,
equipment,  furniture,  fixtures and furnishings (such as appliances,  satellite
television  equipment,  light  fixtures,  drapes  and  window  coverings,  floor
coverings,  laundry equipment,  and office equipment),  inventory,  all property
listed  in  the  Impound  Account,  the  Agreements,  all  drawings,  plans  and
specifications,  and all accounts, contract rights and general intangibles (such
as insurance proceeds and condemnation awards or compensation) arising out of or
incident to the ownership,  development or operation of the Property owned by or
in which Trustor has an interest.

POST CLOSING ACTIONS AGREEMENT:  The Post Closing Actions Agreement of even date
herewith executed by Trustors in favor of Beneficiary.

PREPAYMENT PREMIUM:  As defined in the Note.

PRINCIPAL PARTY(IES):  As defined in PARAGRAPH 6.1.B hereof.

PROCEEDING:  As defined in PARAGRAPH 6.1.B hereof.

PROPERTY:  Each of the Land,  Improvements,  Fixtures,  Personalty and Rents and
Proceeds of each  Trustor as defined in the  Granting  paragraph of this Deed of
Trust,  except that whenever the context so requires,  "Property" shall refer to
the Land,  Improvements,  Fixtures,  Personalty  and Rents and  Proceeds  of all
Trustors.

RECEIVER: Any trustee, receiver,  custodian, fiscal agent, liquidator or similar
officer.

RELEASE FEE:  As defined in PARAGRAPH 4.3 hereof.

RENTS AND PROCEEDS: All rents, royalties,  revenues,  receipts, issues, profits,
proceeds and other income of any kind or  character  from the Leases,  the Land,
the Improvements, the Fixtures, and Transfers.

SECONDARY INTEREST RATE:  As defined in the Note.

SERVICING FEE:  As defined in PARAGRAPH 4.3 hereof.

SUBSTITUTE PROPERTY:  As defined in PARAGRAPH 4.3 hereof.

TRANSFER: Any (i) sale, conveyance,  assignment, transfer, alienation, mortgage,
conveyance of security title,  encumbrance or other disposition of the Property,
of any kind,  or any other  transaction  the  result  of which is,  directly  or
indirectly,  to divest the Trustor of any portion of or interest in its title to
the  Property,  voluntarily  or  involuntarily,  (ii) merger,  consolidation  or
dissolution  involving,  or the sale or transfer of all or substantially  all of
the assets of, the Trustor or any general partner of the Trustor, (iii) transfer
(at one time or over any period of time) of ten percent (10%) or more of (A) the
voting stock of (1) any corporate Trustor,  (2) any corporate general partner of
any Trustor or (3) any corporation  which is the direct or indirect owner of ten
percent  (10%) or more of the  voting  stock  of any  Trustor  or any  corporate
general partner of any Trustor,  (B) the beneficial  interest in the Trustor, or
the  interest  in any  owner of fifty  percent  (50%) or more of the  beneficial
interest in any  Trustor,  if a trust,  or (C) the  ownership  interests  of any
Trustor  if such  Trustor  is a  limited  liability  company  or in any  limited
liability  company which is a direct or indirect general partner of any Trustor,
(iv)  transfer  of any  general  partnership  interest  in any Trustor or in any
partnership  which is a direct or indirect  general partner of any Trustor,  (v)
the conversion of any such general partnership interest to a limited partnership
interest or (vi) transfer of any interest in any managing  member of any Trustor
if such Trustor is a limited liability company. For purposes of this definition,
a "Transfer"  shall not include transfer of title or interest under any will (or
applicable law of descent) or transfers of limited partnership interests.

TRANSFER CONDITIONS:  As defined in PARAGRAPH 4.2 hereof.

                                    ARTICLE 2
                         REPRESENTATIONS AND WARRANTIES

Trustor hereby represents and warrants to Beneficiary and Trustee that as of the
date of this  Deed of Trust  and as of the date of any  subsequent  disbursement
pursuant to the Loan Documents:

2.1. TITLE,  AUTHORIZATION AND ORGANIZATION.  Trustor (i) is the lawful owner of
the Property and holds good and marketable  title to the Property free and clear
of all defects,  liens,  encumbrances,  easements,  exceptions and  assessments,
except the Permitted  Exceptions;  (ii) has the power and authority to grant the
Property  as  provided  in and by this Deed of Trust and to own and  operate the
Property;  (iii) is duly organized,  validly existing and in good standing under
the laws of the State of its  organization  and is duly qualified to do business
in the State in which the Land is located;  and (iv) is in  compliance  with all
Laws and Restrictions.

2.2.  VALIDITY OF LOAN  DOCUMENTS.  The execution,  delivery and  performance by
Trustor of the Loan Documents and the  borrowings  evidenced by the Note (i) are
within the power of Trustor,  (ii) have been authorized by all requisite  action
and (iii) will not violate any Laws and  Restrictions  or any agreement or other
instrument.

2.3. FINANCIAL  STATEMENTS AND OTHER INFORMATION.  All financial  statements and
other reports, papers, data and information given to Beneficiary with respect to
the  Property  and any Loan Party are true,  accurate,  complete and correct and
except  as  expressly  noted to the  contrary  therein,  have been  prepared  in
accordance with generally accepted accounting  principles throughout the periods
covered thereby. There has been no Material Adverse Change since the date of the
most recent financial statement given to Beneficiary.

2.4. LITIGATION. There is not now pending against or affecting any Loan Party or
the Property,  nor to the best of Trustor's  knowledge is there threatened,  any
action, suit or proceeding that might result in a Material Adverse Change.

2.5.  ADDITIONAL  REPRESENTATIONS  AND WARRANTIES.  (i) The Property is not used
principally or primarily for  agricultural or grazing  purposes;  (ii) all costs
for labor and materials for the construction of the Improvements  have been paid
in full;  (iii) Trustor is not aware of any assessment  for public  improvements
which is pending and which could become a lien upon the Property;  (iv) no event
has occurred  which,  with the giving of notice or the passage of time, or both,
would  constitute  an Event of  Default  under  any of the Loan  Documents;  (v)
Trustor is not in default  under any  agreement or  instrument  to which it is a
party which default would have a material and adverse  effect on the Property or
Trustor's ability timely to perform the Obligations;  (vi) neither the Property,
nor any part thereof, has sustained, incurred or suffered any material damage or
destruction;   and  (vii)  subject  to  the  Permitted  Exceptions,   the  Land,
Improvements, Personalty and Fixtures are owned by Trustor free and clear of any
liens, encumbrances, mortgages, security interests, claims and rights of others;
(viii) the  Property  and the  current use  thereof  complies  with all Laws and
Restrictions;  (ix) Trustor has received no notices of  violations  or breach of
any Laws and  Restrictions;  and (x) Trustor has not  received any notice of any
violation with respect to, and to Trustor's  knowledge the  Improvements  are in
material compliance with, The Americans With Disabilities Act of 1990 (42 U.S.C.
ss.ss.12101-12213), including Title III thereof.

2.6.  BANKRUPTCY.  No  petition  in  bankruptcy,   petition  or  answer  seeking
assignment  for the benefit of creditors or appointment of a Receiver or similar
proceeding  with respect to any Principal  Party or Major Tenant has occurred or
is contemplated.

2.7.  FIRPTA  CERTIFICATION.  Trustor  declares and certifies,  under penalty of
perjury, that: (i) Trustor's U.S. Taxpayer I.D. Numbers are as follows:



                                                 
      MISSION WEST PROPERTIES LP:            77-0414489
      MISSION WEST PROPERTIES LP I           94-2883514
      MISSION WEST PROPERTIES LP II          94-2610469
      MISSION WEST PROPERTIES LP III         77-0002956


(ii) the  business  address  of  Trustor  is  10050  Bandley  Drive,  Cupertino,
California 95014;  (iii) Trustor is not a "foreign person" within the meaning of
Sections  1445 and 7701 of the Internal  Revenue  Code of 1986,  as amended (the
"Code");  and (iv) Trustor  understands  that the information and  certification
contained in this PARAGRAPH 2.7 may be disclosed to the Internal Revenue Service
and that any  false  statement  contained  herein  could  be  punished  by fine,
imprisonment  or  both.  Trustor  agrees  to  provide  Beneficiary  with  a  new
certification  containing the provisions of this PARAGRAPH 2.7 immediately  upon
any change in such information.

2.8. ZONING, BUILDING,  ENVIRONMENTAL AND LAND USE LAW Compliance.  The Property
and all uses thereof comply with all applicable zoning, building,  environmental
and other land use laws,  ordinances,  rules and regulations,  and other similar
restrictions  (including  the  Americans  with  Disabilities  Act).  Beneficiary
understands and acknowledges that Trustor has informed  Beneficiary that certain
of the Improvements comprised in the Property comply with such laws, ordinances,
rules,  regulations and other similar  restrictions under provisions which allow
the continued use and occupancy thereof,  notwithstanding  subsequent changes in
such laws,  ordinances,  rules and regulations,  and that all such  Improvements
allowing such continued use and occupancy,  notwithstanding such changes, can be
reconstructed under such laws, ordinances,  rules, regulations and other similar
restrictions  in the event of any  damage or  destruction  to such  Improvements
substantially to their current size (including floor area ratios), and that as a
result thereof there would be no material loss of rentable square footage in any
affected Improvement.  No action or proceeding,  administrative or otherwise, is
pending or threatened  before a court or  administrative  agency with respect to
compliance by the Property with applicable zoning,  building,  environmental and
land use laws, ordinances, rules and regulations and similar restrictions.

2.9. PROPERTY SEPARATELY ASSESSED. Each of the Properties is separately assessed
and taxed in one or more separate  assessor's tax parcels under  applicable real
property and personal tax laws.

2.10. BROKER AND FINDER FEES. Trustor shall pay any and all commissions and fees
of any kind or character due any Person on account of the Loan transaction,  and
shall indemnify,  defend, protect and hold Beneficiary and Trustee harmless from
and against any and all losses, liabilities,  claims, damages, causes of action,
costs and expenses (including  reasonable  attorneys' fees) arising out of or in
connection  with any such  commissions  or fees,  or claims of any  Person  with
respect thereto.


                                    ARTICLE 3
                              AFFIRMATIVE COVENANTS

Trustor hereby covenants and agrees as follows:

3.1. OBLIGATIONS OF TRUSTOR.  Trustor will timely perform, or cause to be timely
performed, all the Obligations.

3.2.  INSURANCE.

      A. Trustor,  at its sole cost and expense,  will keep and maintain for the
      mutual benefit of Trustor and Beneficiary:  (i) insurance  against loss or
      damage  to the  Property  by fire and other  risks  covered  by  insurance
      commonly known as "all risk", including losses sustained by reason of riot
      and civil commotion,  vandalism,  malicious mischief,  burglary, theft and
      mysterious  disappearance,  and coverage for  differences  in building and
      other code  requirements as a reconstruction of any damage or destruction,
      and against such other risks or hazards as  Beneficiary  from time to time
      reasonably may designate in an amount equal to one hundred  percent (100%)
      of the  then-current  "full  replacement  cost" of the  Improvements,  the
      Fixtures, and the Personalty, without deduction for physical depreciation;
      (ii) rental income insurance  against loss of income in an amount equal to
      twelve  (12)  months  rental  and  taxes  and  other   operating   expense
      reimbursements or payments at then-current income levels; (iii) Commercial
      General  Liability   insurance   including  broad  form  property  damage,
      contractual liability and personal injury coverage, with a combined single
      limit and general aggregate in such amounts as are reasonably  approved by
      Beneficiary;   (iv)  "Builders   Risk"   insurance   during  any  material
      construction,  repair,  replacement,   renovation  or  alteration  of  the
      Improvements,  in such amounts as are reasonably  approved by Beneficiary;
      (v) boiler and machinery  insurance  covering  boilers and other  pressure
      vessels,  the air  conditioning  system,  high  pressure  piping and other
      machinery and equipment  required for the operation of the Property;  (vi)
      Workers' Compensation Insurance with employer's liability endorsement; and
      (vii) such other insurance,  and in such amounts, as may from time to time
      be reasonably  required by  Beneficiary,  except that Trustor shall not be
      required to  maintain  earthquake  insurance  and shall not be required to
      maintain  flood  insurance on any Property  that lies outside the 100 year
      flood zone.

      B. The  policies of  insurance  required by this Deed of Trust  shall,  as
      applicable,  (i) be prepaid  annually and otherwise  satisfactory in form,
      substance and amount to Beneficiary and written with  financially  solvent
      companies  satisfactory  to  Beneficiary,  (ii)  name  Beneficiary  as  an
      additional  insured as its interest may appear,  (iii)  contain a Standard
      Lender's  Loss Payable  endorsement  and other  non-contributory  standard
      mortgagee   protection   clauses   acceptable  to   Beneficiary,   and  at
      Beneficiary's  option, a waiver of subrogation rights by the insurer, (iv)
      contain an  agreement  by the insurer that the policy shall not be amended
      or canceled  without at least  thirty (30) days' prior  written  notice to
      Beneficiary,  and (v) shall contain such other  provisions as  Beneficiary
      deems  reasonably  necessary or desirable  to protect its  interests.  Any
      policies  containing a coinsurance clause shall include a replacement cost
      endorsement  adequate  to ensure that the  coinsurance  clause is rendered
      inoperative.  Any Commercial General Liability insurance shall provide (A)
      for  severability  of  interests  or that acts or  omissions of one of the
      insureds  or  additional  insureds  shall not  reduce  or affect  coverage
      available to any other  insured or additional  insured,  and (B) that such
      insurance is primary and  noncontributing  with any  insurance  carried by
      Beneficiary or Trustee.

      C. In the  event a  blanket  policy  is  submitted  to  satisfy  Trustor's
      obligations   under  this   PARAGRAPH  3.2,  in  addition  to  such  other
      requirements  set forth herein,  Trustor  shall  deliver to  Beneficiary a
      certificate from such insurer indicating that Beneficiary is covered under
      such policy as required by this  PARAGRAPH  3.2, and  evidencing  that the
      amount and coverages of such insurance  applicable to the Property  comply
      with the requirements of this PARAGRAPH 3.2.

      D. Trustor shall furnish evidence,  satisfactory to Beneficiary,  that (i)
      all  insurance   requirements   (including   provisions   for  waivers  of
      subrogation) set forth in the Leases or any other agreements affecting the
      Property shall have been  satisfied by each party thereto;  (ii) Trustor's
      insurance  coverage is sufficient  (assuming the total  destruction of the
      Property) to permit Trustor to rebuild the  Improvements  (including basic
      tenant  improvements) and to replace the Fixtures and Personalty in such a
      manner as to enable the  Property  to be  operable  and  rentable as it is
      currently  rented and  operated;  and (iii) each  tenant,  required by the
      terms of its Lease to  maintain  insurance  on its  leased  premises,  has
      caused  Beneficiary  to be named as an  additional  insured  or loss payee
      under such insurance policies.

      E.  Self-insurance  (other  than the  applicable  deductibles  approved by
      Beneficiary) shall not satisfy the requirements of this PARAGRAPH 3.2.

      F. All of  Trustor's  right,  title and interest in and to all policies of
      property  insurance  and any  unearned  premiums  paid  thereon are hereby
      assigned (to the fullest extent  assignable) to Beneficiary who shall have
      the right, but not the obligation,  to assign the same to any purchaser of
      the Property at any foreclosure sale.

      G. Not less than  thirty  (30) days  prior to the  expiration  date of any
      policy  furnished  pursuant to this PARAGRAPH  3.2,  Trustor shall provide
      Beneficiary  with  duplicate  originals  or  certified  copies of  renewal
      policies  together with evidence  satisfactory to Beneficiary of Trustor's
      payment of the applicable premiums.

3.3.  MAINTENANCE,  WASTE AND REPAIR.  Trustor will (i) maintain the Property in
good order and condition; (ii) promptly make, or cause to be made, all necessary
structural  and  non-structural  repairs to the Property;  (iii) not diminish or
materially  alter the  Improvements,  or erect any new buildings,  structures or
building   additions  on  the  Land,   without  the  prior  written  consent  of
Beneficiary;  (iv) not remove or permit to be  removed  any of the  Fixtures  or
Personalty  from the Property  without the prior written  consent of Beneficiary
unless replaced by articles of equal suitability and value owned by Trustor free
and clear of any lien or security interest;  and (v) not permit any waste of the
Property  or make any  change  in the use  thereof,  nor do or permit to be done
thereon anything, that may in any way impair the security of this Deed of Trust.

3.4. IMPOSITIONS;  IMPOUNDS.  Trustor will pay all Impositions when due. Trustor
will  deliver  to  Beneficiary,  within  seven (7) days after  demand  therefor,
receipts  showing the payment of any  Impositions.  Upon the  occurrence  of the
first monetary or material  non-monetary Event of Default (including an Event of
Default under Paragraph  6.1.A(viii)  hereof),  and continuing until twelve (12)
consecutive  calendar  months  have  elapsed  following  cure of such  Event  of
Default,  Trustor will pay monthly to Beneficiary an amount equal to one-twelfth
(1/12th) of the annual cost of Impositions  together with an amount equal to the
estimated  next  premiums  for hazard  and other  required  insurance.  Upon the
occurrence of any subsequent monetary or material  non-monetary Event of Default
(including an Event of Default under Paragraph 6.1.A(viii) hereof), Trustor will
pay such amounts monthly to Beneficiary  until the Indebtedness is paid in full.
These funds will be held by Beneficiary without interest and will be released to
Trustor for payment of Impositions and insurance  premiums,  or directly applied
to such costs by Beneficiary, as Beneficiary may elect.

3.5.  COMPLIANCE WITH LAW. Trustor will promptly and faithfully  comply with and
perform all present and future Laws and Restrictions.

3.6.  BOOKS AND RECORDS AND OTHER INFORMATION.

      A.  Trustor,  without  expense  to  Beneficiary,  will  maintain  full and
      complete  books of  account  and  records  reflecting  the  results of the
      operations  of  the  Property  in  accordance   with  generally   accepted
      accounting  principles,  and will  furnish  or cause  to be  furnished  to
      Beneficiary such information concerning the financial condition of Trustor
      and the Property as Beneficiary shall reasonably request, including annual
      audited  financial  statements and an annual  operating  statement for the
      Property and annual audited financial statements for the Principal Parties
      and, to the extent such  statements are not in the public domain,  but may
      reasonably  be  obtained  by  Trustor,   for  the  Major   Tenants.   Upon
      Beneficiary's reasonable request, Beneficiary shall have the right, at all
      reasonable  times  and upon  reasonable  notice,  to audit  the  books and
      records of Trustor.  If such audit  discloses  a variance of five  percent
      (5%) or more in income or expenses entered in such books and records,  the
      cost of such audit shall be paid by Trustor.

      B.  Trustor  will  furnish  to  Beneficiary,  within  seven (7) days after
      written request therefor,  all information that Beneficiary may reasonably
      request  concerning  the  Property  or the  performance  by Trustor of the
      Obligations.

      C. Trustor shall keep at either its principal  place of business or at the
      offices at the Property,  and make available to Beneficiary  during normal
      business hours, as-built plans and specifications or, if unavailable,  the
      final set of plans and  specifications  from which the  Improvements  were
      constructed  ("As-Builts"),  certified by a licensed architect or licensed
      contractor as true, correct and complete As-Builts.

3.7. FURTHER  ASSURANCES.  Trustor,  at any time upon the reasonable  request of
Beneficiary,  will at Trustor's  expense,  execute,  acknowledge and deliver all
such additional  papers and  instruments  (including a declaration of no setoff)
and perform all such further acts as may be reasonably  necessary to perform the
Obligations and, as Beneficiary deems necessary, to preserve the priority of the
lien of this Deed of Trust and to carry out the purposes of the Loan Documents.

3.8. LITIGATION.  Trustor will promptly give notice in writing to Beneficiary of
any  litigation  or other event or  occurrence  which might result in a Material
Adverse Change.

3.9. INSPECTION OF PROPERTY.  Trustor hereby grants to Beneficiary,  its agents,
employees, consultants and contractors, the right to enter upon the Property for
the purpose of making any and all  inspections,  reports,  tests,  inquiries and
reviews as Beneficiary (in its sole and absolute  discretion) deems necessary to
assess  the then  current  condition  of the  Property,  or for the  purpose  of
performing any of the other acts Beneficiary is authorized to perform  hereunder
upon 72 hours  prior  notice to Trustor,  except  that such notice  shall not be
required (i) if an Event of Default  shall have  occurred and remain  uncured or
(ii) in the event of an emergency.  Trustor shall cooperate with  Beneficiary to
facilitate such entry and the  accomplishment of such purposes.  All costs, fees
and expenses  (including those of  Beneficiary's  legal counsel and consultants)
incurred  by  Beneficiary  with  respect to such  inspections,  reports,  tests,
inquiries and reviews shall be paid by Trustor to Beneficiary upon demand, shall
accrue interest at the Secondary  Interest Rate until paid, and shall be secured
by this Deed of Trust.

3.10. CONTEST. Notwithstanding the provisions of PARAGRAPHS 3.4 AND 3.5, Trustor
may, at its expense, upon written notice to Beneficiary, contest the validity or
application  of  any  Impositions  or  Laws  and   Restrictions  by  appropriate
administrative or legal proceedings  promptly initiated and diligently conducted
in good faith,  provided that (i)  Beneficiary is reasonably  satisfied that the
priority of this Deed of Trust shall be maintained  and neither the Property nor
any part thereof or interest therein will be in danger of being sold, forfeited,
or lost as a result of such  contest,  and (ii) if the  amount of the  contested
Imposition or the cost to comply with the  contested  Laws and  Restrictions  is
likely to exceed One Million  Dollars  ($1,000,000.00)  if decided  adversely to
Trustor,  or if an Event of Default has occurred or occurs and remained uncured,
Trustor  shall have  posted a bond or  furnished  such other  security as may be
reasonably required from time to time by Beneficiary.

3.11. ADDITIONAL INFORMATION.  Trustor will furnish to Beneficiary, within seven
(7)  days  after  written  request  therefor,   any  and  all  information  that
Beneficiary may reasonably request concerning the Property or the performance by
Trustor of the Obligations.

3.12.  PREPAYMENT.  Trustor may prepay the Loan only on the terms and conditions
set forth in the Note and Trustor shall pay  Beneficiary  prepayment  charges in
respect of any prepayment,  whether voluntary or involuntary, as required by and
on the terms and conditions set forth in the Note.

3.13. FIRPTA CERTIFICATE.  In the event of any Transfer by Trustor of its rights
hereunder or of any interest in the Property otherwise permitted under this Deed
of Trust,  the transferee  shall,  as an additional  condition to such Transfer,
under  penalty of  perjury,  execute and deliver to  Beneficiary  a  certificate
concerning  the  non-foreign  status  of  Trustor  substantially  in the form of
PARAGRAPH 2.7 hereof.  Nothing in this paragraph  shall be deemed a modification
or  waiver  of any  other  provision  of any of  the  Loan  Documents  limiting,
prohibiting  or  otherwise  relating  to any  Transfer  of any  interest  in the
Property or Trustor.

3.14. TAX SERVICE  CONTRACT.  So long as any Loan Document remains in effect, at
Trustor's  sole expense,  Beneficiary  shall be furnished tax service  contracts
issued by a tax reporting agency satisfactory to Beneficiary.

3.15. TRUSTOR'S OBLIGATIONS WITH RESPECT TO LEASE OF CISCO Systems. In the event
that Cisco Systems  ("Cisco")  exercises the right of first offer or purchase of
the Property  covered by its Lease (the "Cisco  Property"),  Trustor shall cause
Cisco to deposit the proceeds of such sale payable by Cisco to an escrow account
under the  control of  Beneficiary  established  with a title  company  mutually
acceptable  to Trustor and  Beneficiary.  Unless an Event of Default  shall have
occurred and remain uncured,  Trustor may, following consummation of the sale of
the Cisco  Property  to Cisco,  (i) elect to  replace  the Cisco  Property  with
substitute   collateral  pursuant  to  Paragraph  4.3  hereof,  in  which  event
Beneficiary  shall  release  the  proceeds  to  Trustor  concurrently  with  the
consummation of the  substitution  of collateral,  or (ii) apply the proceeds to
prepay the  Indebtedness,  which  payment shall  constitute a Prepayment  Amount
under the Note.


                                    ARTICLE 4
                               NEGATIVE COVENANTS

Trustor hereby covenants to and agrees as follows:

4.1.  RESTRICTIVE  USES.  Trustor will not initiate,  join in, or consent to any
change in the current use of the  Property or in any zoning  ordinance,  private
restrictive  covenant,   assessment  proceedings  or  other  public  or  private
restriction limiting or restricting the uses that may be made of the Property or
any part thereof or in any way change the boundaries of the Property without the
prior written consent of Beneficiary.

4.2.  PROHIBITED TRANSFERS.

      A. Except as  otherwise  provided  in  PARAGRAPHS  4.2.B and 4.2.C  below,
      Trustor shall not participate in, and shall not cause,  allow or otherwise
      permit, a Transfer without the prior written consent of Beneficiary, which
      consent  may be given or  withheld  for any  reason  (or for no reason) or
      given conditionally (including a requirement that the permitted transferee
      assume in writing,  in form and substance  satisfactory  to Beneficiary in
      its  sole  discretion,   all  of  Trustor's  Obligations  under  the  Loan
      Documents,   the  Hazardous   Substances  Agreement  and  the  Certificate
      Regarding  Distribution of Loan Proceeds and Indemnity Agreement and agree
      to be  bound  thereby),  as  determined  by  Beneficiary  in its  sole and
      absolute discretion, and any default, failure to observe, or breach of the
      provisions of this  PARAGRAPH 4.2 shall  constitute an immediate  Event of
      Default  hereunder  and,  at the option of  Beneficiary,  Beneficiary  may
      accelerate the Indebtedness whereby the entire Indebtedness (including any
      Prepayment  Premium)  shall  become  immediately  due  and  payable.   Any
      assumption of Trustor's obligations hereunder shall not, however,  release
      any Loan  Party  from  any  liability  under  the  Loan  Documents  or the
      Hazardous  Substances  Agreement.   This  provision  shall  not  apply  to
      transfers of title or interest  under any will or testament or  applicable
      law of descent or transfers of limited  partnership  interests in Trustor.
      Consent to any such Transfer by  Beneficiary  shall not be deemed a waiver
      of  Beneficiary's  right to require  such consent to any further or future
      Transfers.

      B.  Notwithstanding  the foregoing,  the following  Transfers shall not be
      prohibited and shall not,  except as otherwise  provided in this PARAGRAPH
      4.2.B, require Beneficiary's consent, or if effectuated in accordance with
      the terms and conditions of this PARAGRAPH  4.2.B,  constitute an Event of
      Default under the Loan Documents: (i) the Transfer of shares of any Person
      which is a publicly  traded company with its shares listed and traded on a
      national exchange in the United States of America, so long as the Transfer
      is  executed  in the  ordinary  course of trading  of such  shares on such
      exchange,  (ii)  the  issuance  by  any  Loan  Party  of  publicly  traded
      securities,   whether  or  not  in  connection  with  the  acquisition  of
      properties; (iii) the conversion of Operating Partnership Units in Trustor
      to common stock in Mission West, or in a Person that is a publicly  traded
      company  with its shares  listed and traded on a national  exchange in the
      United  States of America,  subject to the  satisfaction  of the  Transfer
      Conditions; (iv) the issuance of Operating Partnership Units in Trustor in
      connection  with the  acquisition of  properties,  so long as the proposed
      transaction  complies  with all ERISA  requirements  contained in the Loan
      Documents  and,  if a  change  occurs  in  the  identity  of  the  Persons
      controlling the major decision making  management  level of Trustor and/or
      Mission West in connection with such transaction,  subject additionally to
      the  satisfaction  of the other  Transfer  Conditions;  (v) subject to the
      satisfaction of the Transfer  Conditions,  the acquisition of Mission West
      through merger,  tender offer, exchange offer or sale of substantially all
      the assets of Mission West (each a "Mission West Merger  Transaction") and
      (vi) subject to the satisfaction of the Transfer Conditions, the merger of
      Mission  West  Properties,  a  California  corporation,  with  and  into a
      wholly-owned  subsidiary named Mission West  Properties,  Inc., a Maryland
      corporation  ("MWP,  Inc."),  provided  that  MWP,  Inc.  has no assets or
      liabilities immediately prior to the merger and provided further that such
      merger  follows the plan set forth in Trustor's  current S-4  Registration
      Statement  in the section  titled "The  Reincorporation  Merger." The term
      "Transfer Conditions" shall mean each of the following  requirements:  (A)
      Beneficiary  receives at least thirty (30) days' prior  written  notice of
      the Transfer;  (B) there is no Event of Default  under the Loan  Documents
      (or event which with the passage of time or the giving of notice, or both,
      would be an Event of Default)  which has occurred and is  continuing;  (C)
      the proposed transaction complies with all ERISA requirements contained in
      the Loan Documents  (including  receipt by Beneficiary of such evidence as
      it may  require in its sole  discretion  to  determine  that the  proposed
      Transfer  is not and would not  render the Loan a  prohibited  transaction
      under  ERISA);  (D) if deemed  applicable  by  Beneficiary,  the  proposed
      transferee shall have signed a written  assumption  agreement with respect
      to the Loan  Documents in form and substance  acceptable to Beneficiary in
      its sole discretion;  (E) the proposed  transferee shall have provided all
      information about the proposed transferee requested by Beneficiary; (F) in
      the event of a  Mission  West  Merger  Transaction,  Beneficiary  shall be
      satisfied with the  creditworthiness,  good character and reputation,  and
      demonstrated  ability and experience (by itself or through its manager) in
      the ownership, operation, and leasing of property similar to the Property,
      of the successor entity to Mission West, except that in no event shall the
      net worth  (excluding for purposes of this  calculation,  the Property) of
      the successor  entity based on market value, as determined by Beneficiary,
      be less than  $250,000,000.00;  and (G) payment by Trustor or the proposed
      transferee of (1) all costs and expenses  incurred by Beneficiary  for the
      processing  of the Transfer,  including a processing  fee as determined by
      Lender,  (2) any documentary  stamp taxes,  intangibles  taxes,  recording
      fees,  and other  costs  and  expenses  required  in  connection  with any
      assumption  agreement and any modification of the Loan Documents,  and (3)
      all other costs and expenses  (including  attorneys' fees and expenses for
      Beneficiary's  staff attorneys and outside  counsel) of the preparation of
      any assumption agreement and any modification of the Loan Documents.

      C.  Notwithstanding  PARAGRAPHS  4.2.A  and  4.2.B  above,  if no Event of
      Default or event  which with the  passage of time or the giving of notice,
      or both,  would  constitute  an  Event  of  Default  has  occurred  and is
      continuing, Beneficiary shall, upon thirty (30) days prior written request
      by Trustors, consent to a one-time Transfer of the entire Property if: (i)
      the proposed transferee is a Person which, in the judgment of Beneficiary,
      has  financial  capability  and  creditworthiness  of  Trustors,  and  the
      reputation  and  experience in the  ownership,  operation,  management and
      leasing of similar  properties,  equal to or greater  than  Mission  West,
      except that under no  circumstances  shall the proposed  transferee have a
      net worth (excluding, for purposes of this calculation, the Property) less
      than $100,000,000.00; (ii) at the time of Transfer the Loan to Value Ratio
      does  not  exceed  fifty-five   percent  (55%);   (iii)  Trustors  pay  to
      Beneficiary  a fee equal to  one-half  of one  percent  (1/2%) of the then
      outstanding   principal   balance  of  the  Loan   concurrently  with  the
      consummation of such Transfer;  (iv) at Beneficiary's option,  Beneficiary
      has received an  endorsement  to  Beneficiary's  title policy at Trustors'
      expense,  which endorsement states that this Deed of Trust remains a first
      and prior lien against the Property  (excluding the  Personalty);  (v) the
      Debt  Service  Coverage  Ratio is at least 1.85 to 1.00 for the  preceding
      twelve (12) month period and Beneficiary  receives  satisfactory  evidence
      that such Debt  Service  Coverage  Ratio will be  maintained  for the next
      succeeding  twelve (12) months;  (vi) the transferee in writing  expressly
      assumes the Obligations under the Loan Documents,  and under the Hazardous
      Substances Agreement, and executes any other documents reasonably required
      by  Beneficiary,  and such  assumptions  and all such other  documents are
      satisfactory  in form and  substance  to  Beneficiary;  (vii)  Beneficiary
      reasonably  approves  the form and content of all Transfer  documents  and
      Beneficiary is furnished  with a certified  copy of the recorded  Transfer
      documents; (viii) the proposed transferee complies with ERISA and delivers
      the ERISA  certification  and  indemnification  agreements  required under
      PARAGRAPH 9.18 hereof;  and (ix) Trustors or the proposed  transferee pays
      all  reasonable  fees,  costs and  expenses  incurred  by  Beneficiary  in
      connection  with such  Transfer,  including  all legal  (both for  outside
      counsel and Beneficiary's staff attorneys),  accounting,  title insurance,
      documentary  stamp or transfer taxes,  intangible  taxes,  mortgage taxes,
      recording  fees,  and  appraisal  fees,  whether or not such  Transfer  is
      actually consummated.

4.3. SUBSTITUTION OF SECURITY.  Notwithstanding PARAGRAPH 4.2 above, and so long
as there is no Event of Default  under the Loan  Documents  (or event which with
the  passage  of time or the  giving of  notice,  or both,  would be an Event of
Default which has occurred and is continuing),  Beneficiary  shall,  upon thirty
(30) days' prior written request by Trustor, subject to the conditions set forth
below,  release from the lien of this Deed of Trust the entirety of any Eligible
Transfer Property identified in EXHIBIT B hereto:

      (i) Trustor  grants to Beneficiary a first lien in the fee simple title of
   a replacement property (the "Substitute  Property") owned one hundred percent
   (100%) by the Trustor which owns the Eligible Transfer Property that is being
   released  (which  lien  shall be in the form of this Deed of Trust  with only
   such changes  thereto as Beneficiary may  incorporate,  from time to time, in
   the form of deed of trust then utilized by Beneficiary in securing commercial
   mortgage  loans  similar  to the Loan to address  developments  in the law of
   concern to  Beneficiary in  implementing  its mortgage  lending  practices in
   California)  (the  "Substitute  Deed of  Trust")  and  Trustor  executes  and
   delivers to Beneficiary such approvals,  opinions,  documents and other items
   as Beneficiary may reasonably  request in connection with the substitution of
   security for, and the perfection of Beneficiary's  security  interest in, the
   Substitute Property;

      (ii)  Beneficiary  shall not be required to release any Eligible  Transfer
   Property if the sum of the aggregate Original Allocated Loan Amount (as shown
   on EXHIBIT B hereto) of the Eligible Transfer Property for which a release is
   sought and of all other  Eligible  Transfer  Properties  which  prior to such
   release  have been  released  from the lien of this  Deed of  Trust,  exceeds
   $65,000,000.00;

      (iii)  Trustor  pays  Beneficiary  a  non-refundable  servicing  fee  (the
   "Servicing  Fee") at the time of  Trustor's  request in the amount of Fifteen
   Thousand  Dollars  ($15,000.00)  for each  Eligible  Transfer  Property  that
   Trustor is requesting to be released from the lien of this Deed of Trust;

      (iv)  Trustor  pays  to  Beneficiary  at  the  time  the  substitution  of
   collateral is effected a release fee (the "Release Fee") equal to one-half of
   one percent  (1/2%) of the Original  Allocated  Loan  Amount,  as adjusted to
   reflect  amortization  of principal  that has  occurred  from the date of the
   recording of this Deed of Trust to the date the substitution of collateral is
   effected,  for each Eligible  Transfer Property that Trustor is requesting to
   be  released  from  the  lien of this  Deed of  Trust,  except  that  (A) the
   Servicing  Fee shall be credited  against the Release  Fee,  and (B) under no
   circumstances  shall the  Release  Fee exceed  $75,000.00  for each  Eligible
   Transfer Property;

      (v)  Beneficiary  receives a 1970 form ALTA title  policy  (including  any
   endorsements thereto deemed necessary by Beneficiary) insuring the first lien
   priority of the Substitute Deed of Trust encumbering the Substitute Property,
   subject only to the lien of real property taxes not delinquent and such other
   exceptions  to  title  approved  by  Beneficiary  in its  sole  and  absolute
   discretion,   with  liability  coverage  in  the  amount  of  the  Loan,  and
   Beneficiary  receives such other title assurances as it may request to ensure
   that its first lien priority in the Property that is not being  released will
   continue unaffected by the release of the Eligible Transfer Property;

      (vi) the  Substitute  Property shall satisfy,  in  Beneficiary's  sole and
   absolute discretion, Beneficiary's then-current mortgage lending requirements
   and underwriting criteria in all respects, including requirements relating to
   environmental and hazardous materials matters,  provided, except that without
   limiting the foregoing,  under no circumstances  shall a Substitute  Property
   qualify for substitution for an Eligible Transfer  Property  hereunder unless
   the Substitute Property is, in Beneficiary's sole judgment, at least equal to
   the  corresponding  Eligible  Transfer  Property  in  each  of the  following
   respects:  (A)  appraised  value,  (B)  stability  of cash flow,  taking into
   consideration  weighted  average  lease  maturities,  (C)  tenant  credit and
   quality and diversification,  (D) building quality and  diversification,  and
   (E) location quality and diversification;

      (vii) the Substitute Property shall be a research and development building
   (or  buildings  contiguous  to each other)  located in the San  Francisco Bay
   Area, as defined by Beneficiary;

      (viii) the Debt Service  Coverage  Ratio for the Property is at least 1.50
   to 1.00 for the  preceding  twelve  month  period  and  Beneficiary  receives
   satisfactory   evidence  that  such  Debt  Service  Coverage  Ratio  will  be
   maintained for the next succeeding twelve (12) months;

      (ix) Beneficiary receives  satisfactory  evidence that the prospective Net
   Operating Income for the Substitute  Property for the succeeding  twelve (12)
   months  will be not less  than one  hundred  ten  percent  (110%) of the then
   current Net Operating
   Income of the Eligible Transfer Property.

      (x) Beneficiary determines, in its sole and absolute discretion,  that the
   release and  substitution  of  collateral  would not result in a violation of
   ERISA,  including the ERISA  provisions  contained in this Deed of Trust, and
   Trustor delivers such  certifications  and other documents as Beneficiary may
   request in connection therewith; and

      (xi) Trustor pays all reasonable  fees,  costs,  and expenses  incurred by
   Beneficiary  in  connection  with  the  proposed  release  and  substitution,
   including  all legal (for both  Beneficiary's  staff  attorneys  and  outside
   counsel),  accounting, title insurance,  documentary stamps taxes, intangible
   taxes, mortgage taxes, recording fees, and appraisal fees, whether or not the
   release and/or substitution is actually consummated.

4.4. NO  COOPERATIVE OR  CONDOMINIUM.  Trustor shall not operate the Property or
permit the Property to be operated as a cooperative  or condominium or otherwise
such that the  tenants  or  occupants  participate  in  ownership,  control,  or
management of the Property.

4.5. PARTNERSHIP OR OPERATING AGREEMENT.  Trustor, if a partnership or a limited
liability   company,   will  not  terminate,   permit  the  termination  of,  or
substantially amend the partnership  agreement or operating  agreement,  without
Beneficiary's prior written consent. As used herein, "substantially amend" means
any amendment, modification, or alteration that would cause or result in (i) the
change of control of the  Trustor,  (ii) the change of the name of the  Trustor,
(iii) the change of the nature of the  business or  operations  of the  Trustor,
(iv) the revocation or purported  repudiation of any  Obligations of the Trustor
under  the Loan  Documents,  (v) the  termination  of the lien  and/or  security
interest  in and to the  Property  under the Loan  Documents  or (vi) a Material
Adverse Change. Nothing in this PARAGRAPH 4.5 shall affect any other Obligations
of Trustor under the Loan Documents,  the Hazardous  Substances Agreement or the
Certificate Regarding Distribution of Loan Proceeds and Indemnity Agreement.

                                    ARTICLE 5
                           CASUALTIES AND CONDEMNATION

5.1.  INSURANCE AND CONDEMNATION PROCEEDS.

      A.  Trustor  shall  notify  Beneficiary  in writing  immediately  upon the
      occurrence  of any loss or damage by fire or other  casualty to any of the
      Property  or  upon  obtaining   knowledge  of  the   commencement  of  any
      proceedings for condemnation of any of the Property.  Beneficiary shall be
      entitled  to (i)  participate  in any such  condemnation  proceedings  and
      Trustor  from time to time will  deliver to  Beneficiary  all  instruments
      reasonably necessary to permit such participation,  and (ii) if the repair
      of the loss or  casualty  is  reasonably  estimated  to cost more than One
      Million  Dollars  ($1,000,000.00)  or if an Event of  Default  shall  have
      occurred and remain uncured  (either,  an "Insurance  Event"),  settle and
      adjust all insurance  claims  relative to any such damage or  destruction,
      deducting from any insurance  proceeds the amount of all expenses incurred
      by  Beneficiary  in connection  with any such  settlement  or  adjustment.
      Notwithstanding  anything  to the  contrary  contained  in  any  insurance
      policies if an Insurance  Event  pertains,  all  proceeds  paid to Trustor
      under any insurance policies required to be maintained by Trustor pursuant
      to PARAGRAPH 3.2 or otherwise relating to the Property,  and any insurance
      proceeds  received  by Trustor  under  insurance  policies  maintained  by
      tenants pursuant to a lease obligation,  shall immediately be delivered to
      Beneficiary.

      B. If  Beneficiary  elects or is  required to make  insurance  proceeds or
      condemnation  awards available for repair or  reconstruction,  Beneficiary
      shall, through a disbursement  procedure established by Beneficiary,  make
      available  to  Trustor  the  net  amount  of  all  insurance  proceeds  or
      condemnation   awards   received  by   Beneficiary   after   deduction  of
      Beneficiary's  reasonable costs and expenses, if any, in collection of the
      same  (the  "Net  Proceeds").  Beneficiary  shall  make  the Net  Proceeds
      available  to  Trustor  for  repair or  reconstruction  if (i) no Event of
      Default or event,  which with the passage of time or the giving of notice,
      or both,  would  constitute  an  Event  of  Default  has  occurred  and is
      continuing;  (ii)  Beneficiary  is satisfied that (A) the Property can and
      will be  repaired  or  reconstructed  within  18  months  from the date of
      damage,  destruction  or  condemnation  to the  condition  of the Property
      immediately prior to the damage, destruction or condemnation in accordance
      with plans and specifications  approved by Beneficiary,  (B) the repair or
      reconstruction  shall be  finally  completed  on a date  which is at least
      twenty-four  (24) months prior to the maturity of the Loan, and (C) Leases
      which are terminated or terminable as a result of such damage, destruction
      or  condemnation  cover an aggregate  rentable square footage of less than
      ten percent (10%) of the total rentable  square  footage  contained in the
      Property  subject to the  condemnation  or  casualty at the closing of the
      Loan;  (iii) Trustor shall have entered into a  construction  contract for
      completion of the repair or reconstruction with a general contractor which
      is acceptable in all respects to the Beneficiary (which general contractor
      may be a Loan Party or an affiliate thereof, provided that such Loan Party
      or affiliate  shall be required to obtain three (3)  competitive  sub-bids
      for each  component of the work of repair or  reconstruction  if the total
      cost of completion of the repair or reconstruction is likely to exceed One
      Million  Dollars  [$1,000,000.00]),  and which  contract must in any event
      include  provisions for retention of not less than ten percent (10%) until
      full and final, lien-free completion of the repair or reconstruction and a
      final completion date which is at least 24 months prior to the maturity of
      the Loan, and (iv) in Beneficiary's  reasonable judgment, the security for
      the Loan has not been  materially  impaired  as a result  of such  damage,
      destruction or condemnation.  In the event  Beneficiary  elects not, or is
      not  required,   to  make  the  Net  Proceeds   available  for  repair  or
      reconstruction,  Beneficiary,  at its  sole  option,  may  apply  the  Net
      Proceeds in payment of the  Indebtedness  or in  satisfaction of any other
      Obligation in such order as Beneficiary may determine provided that if (1)
      Beneficiary applies the Net Proceeds to the Indebtedness and the amount of
      Net Proceeds equals the Original  Allocated Loan Amount for the particular
      Property that suffered the casualty, or (2) in the event such Net Proceeds
      are less than the Original Allocated Loan Amount, Trustor pays Beneficiary
      the  difference  between  the  Original  Allocated  Loan  Amount  and  Net
      Proceeds,  in either such event,  then, so long as no Event of Default has
      occurred  and remains  uncured,  Beneficiary  shall  release the  affected
      Property  which  suffered the casualty from the lien of this Deed of Trust
      and the other Loan Documents. A payment by Trustor to Beneficiary pursuant
      to the foregoing clause shall not be considered a Prepayment  Amount under
      the  Note.  Notwithstanding  any  provision  of this  Deed of Trust to the
      contrary, under no circumstance shall Beneficiary be obligated to make any
      portion of the Net Proceeds available for repair or reconstruction  unless
      at the time of the request for any  disbursement  it has determined in its
      reasonable  discretion that the repair or reconstruction  can be completed
      at a cost (which  cost shall  include  all  payments  coming due under the
      terms of the Loan) which does not exceed the  aggregate  of the  remaining
      Net Proceeds and any funds deposited with Beneficiary by Trustor.

      C. The Net Proceeds  and any  additional  funds  deposited by Trustor with
      Beneficiary,  plus any loss of rental income insurance proceeds which have
      been deposited with  Beneficiary or which the carrier has  acknowledged to
      be payable,  shall constitute  additional  security for the Loan.  Trustor
      shall  execute,  deliver,  file and/or  record,  at its own expense,  such
      documents and instruments as Beneficiary  requires to grant to Beneficiary
      a perfected, first priority security interest in the Net Proceeds and such
      additional funds.

5.2. ADDITIONAL PROVISIONS RELATING TO CONDEMNATION.  Trustor,  immediately upon
obtaining  knowledge of the commencement of any proceedings for the condemnation
of the entire Property or any material part thereof, will notify Trustee and the
Beneficiary of the pendency of such  proceedings.  Trustee and  Beneficiary  may
participate in any such  proceedings  and Trustor from time to time will deliver
to  Beneficiary  all  instruments   requested  by  Beneficiary  to  permit  such
participation.  In the  event of such  condemnation  proceedings,  the  award or
compensation  payable is hereby  assigned  to and shall be paid to  Beneficiary.
Beneficiary  shall be under no  obligation  to  question  the amount of any such
award or  compensation  and may  accept the same in the amount in which the same
shall  be  paid.  In  any  such  condemnation  proceedings,  Beneficiary  may be
represented by counsel  selected by Beneficiary,  the cost of such counsel to be
borne by Trustor.  The proceeds of any award or  compensation so received shall,
at the  option  of  Beneficiary,  either be  applied  to the  prepayment  of the
Indebtedness or  satisfaction of any Obligation,  or be paid over to the Trustor
for  restoration  of the  Improvements  in  accordance  with the  provisions  of
PARAGRAPH 5.1. Trustor hereby  unconditionally and irrevocably waives all rights
of a property owner under Section  1265.225(a)  of the California  Code of Civil
Procedure, or any successor statute providing for the allocation of condemnation
proceeds between a property owner and a lien holder.

                                    ARTICLE 6
                  EVENTS OF DEFAULT AND REMEDIES OF BENEFICIARY

6.1.  EVENTS OF DEFAULT.

      A. It  shall  constitute  an  Event  of  Default  hereunder  if any of the
      following events shall occur and Beneficiary,  by written notice delivered
      to Trustors,  declares an Event of Default:  (i) Trustor shall fail to pay
      within  five (5) days of the date  when due any part of the  Indebtedness;
      (ii)  Trustor  shall  fail to timely  observe,  perform or  discharge  any
      Obligation,  other than as described in PARAGRAPHS 6.1.A.(I), (III), (IV),
      (V), (VI), (VII) AND (VIII),  and any such failure shall remain unremedied
      for thirty  (30) days (the  failure  under this  clause  (ii)  hereinafter
      referred  to as the  "Grace  Period"),  after  notice  to  Trustor  of the
      occurrence of such failure; provided, however, that Beneficiary may extend
      the Grace Period up to ninety (90) days if (A)  Beneficiary  determines in
      good faith that (1) such  failure  cannot be cured within the Grace Period
      but can be cured within ninety (90) days, (2) no lien or security interest
      created by the Loan Documents would be impaired prior to the completion of
      such  cure,  and (3)  Beneficiary's  immediate  exercise  of any  remedies
      provided  hereunder  or by law is not  necessary  for  the  protection  or
      preservation of the Property or Beneficiary's  security  interest therein,
      and (B) Trustor shall immediately  commence and diligently pursue the cure
      of such default;  (iii) Trustor,  as lessor or sublessor,  as the case may
      be,  shall  assign the Rents and  Proceeds  without  first  obtaining  the
      written  consent  of  Beneficiary;  (iv)  default  by  Trustor  after  the
      expiration of all applicable  grace or cure periods under any agreement to
      which Trustor is a party,  other than the Loan Documents,  which agreement
      relates to the  borrowing  of money by Trustor  from any Person,  and such
      default might give rise to a Material  Adverse Change or adversely  affect
      the  security for the Loan;  (v) any  representation  or warranty  made by
      Trustor  in,  under  or  pursuant  to the  Loan  Documents  was  false  or
      misleading  in  any  material  respect  as  of  the  date  on  which  such
      representation or warranty was made or deemed remade; (vi) any of the Loan
      Documents  shall cease to be in full force and effect or be declared  null
      and void, or shall cease to constitute  valid and subsisting  liens and/or
      valid and perfected security interests in and to the Property,  or Trustor
      shall  contest or deny in writing  that it has any  further  liability  or
      obligation  under any of the Loan  Documents;  (vii) the  occurrence  of a
      Material  Adverse  Change;  or  (viii)  any  default  by  Trustor  on  its
      obligations  under the Lease between Trustor,  as successor in interest to
      Berg & Berg Enterprises,  Inc. ("Berg & Berg"), a California  corporation,
      as "Lessor," and Avnet,  Inc., a New York corporation,  as "Lessee," dated
      October  27,  1997,   as  amended  (the  "Avnet   Lease"),   to  construct
      improvements  described  therein  as  "Phase  II" in the time  and  manner
      required by the Avnet Lease.

      B.  It  shall  constitute  an  Event  of  Default  hereunder  without  the
      requirement of any notice by  Beneficiary  if any of the following  events
      shall occur:  (i) Trustor,  any other Loan Party,  any general  partner or
      managing  member of any Loan  Party  which is a  partnership  or a limited
      liability  company,  as the case may be,  any  parent  company of any such
      general partner or managing  member,  or any owner of the Property (each a
      "Principal  Party,"  and  collectively,  the  "Principal  Parties")  shall
      generally  not pay its debts as they  become due or shall admit in writing
      its  inability to pay its debts,  or shall have made a general  assignment
      for the benefit of creditors;  (ii) any Principal Party shall commence any
      case,  proceeding  or other action  seeking  reorganization,  arrangement,
      adjustment,  liquidation,  dissolution  or  composition of it or its debts
      under any law relating to bankruptcy, insolvency, reorganization or relief
      of debtors,  or seeking to have an order for relief entered  against it as
      debtor, or seeking appointment of a receiver,  trustee, custodian or other
      similar official for it or for all or any substantial part of its property
      (collectively,  a "Proceeding");  (iii) any Principal Party shall take any
      action to  authorize  any of the actions set forth above in clauses (i) or
      (ii); (iv) any Proceeding shall be commenced  against any Principal Party,
      and such  Proceeding  (A)  results  in the  entry of an order  for  relief
      against it which is not fully stayed  within seven (7) business days after
      the entry  thereof or (B) remains  undismissed  for a period of forty-five
      (45) days; (v) any Principal Party shall liquidate,  dissolve or otherwise
      terminate their corporate, limited liability company, partnership or other
      entity  organizational  structure  without  the prior  written  consent of
      Beneficiary;  or (vi) failure to timely observe,  perform or discharge any
      provision of PARAGRAPH 4.2 hereof or the occurrence of a Transfer  without
      Beneficiary's  prior  written  consent,  when  such  consent  is  required
      pursuant to PARAGRAPH 4.2.

6.2.  REMEDIES.

      A. Upon the  occurrence  of any Event of Default,  Beneficiary  may at any
      time  declare all of the  Indebtedness  to be due and payable and the same
      shall  thereupon  become  immediately  due and payable,  together with all
      payments due in accordance with the terms of the Note, without any further
      presentment,  demand,  protest or notice of any kind.  Beneficiary may, in
      its sole  discretion,  also do any of the  following:  (i) in  person,  by
      agent, or by a Receiver,  without regard to the adequacy of security,  the
      solvency of Trustor or the condition of the Property,  without  obligation
      so to do and without notice to or demand upon Trustor, enter upon and take
      possession of the Property, or any part thereof, in its own name or in the
      name of  Trustee  and do any acts which  Beneficiary  deems  necessary  to
      preserve the value or marketability of the Property;  sue for or otherwise
      collect  the Rents and  Proceeds,  and  apply  the  same,  less  costs and
      expenses of operation and collection, including reasonable attorneys' fees
      (including  court  costs,  expert  witness  fees,  document   reproduction
      expenses,  costs of exhibit  preparation,  courier  charges,  postage  and
      communication  expenses),  against the  Obligations,  all in such order as
      Beneficiary  may determine;  appear in and defend any action or proceeding
      purporting  to affect,  in any manner  whatsoever,  the  Obligations,  the
      security  hereof or the rights or powers of Beneficiary  or Trustee;  pay,
      purchase  or  compromise  any  encumbrance,  charge  or  lien  that in the
      judgment of  Beneficiary  or Trustee is prior or superior  hereto;  and in
      exercising any such powers, pay necessary expenses, employ counsel and pay
      reasonable  attorneys' fees (including  court costs,  expert witness fees,
      document  reproduction  expenses,  costs of exhibit  preparation,  courier
      charges, postage and communication  expenses);  (ii) as a matter of strict
      right and without notice to Trustor or anyone claiming under Trustor,  and
      without  regard to the then value of the  Property,  apply ex PARTE to any
      court  having  jurisdiction  to appoint a Receiver  to enter upon and take
      possession  of the  Property,  and  Trustor  hereby  waives  notice of any
      application therefor,  provided a hearing to confirm such appointment with
      notice  to  Trustor  is set  within  the time  required  by law (any  such
      Receiver  shall have all the powers  and  duties of  Receivers  in like or
      similar  cases and all the  powers and  duties of  Beneficiary  in case of
      entry as provided herein, and shall continue as such and exercise all such
      powers until the date of confirmation of sale, unless such receivership is
      sooner  terminated);  (iii)  commence an action to foreclose  this Deed of
      Trust in any manner provided hereunder or by law; (iv) with respect to any
      Personalty,  proceed  as  to  both  the  real  and  personal  property  in
      accordance with Beneficiary's  rights and remedies in respect of the Land,
      or proceed to sell said  Personalty  separately  and without regard to the
      Land in accordance with  Beneficiary's  rights and remedies as to personal
      property;  and/or (v) deliver to Trustee a written  declaration of default
      and demand for sale, and a written notice of default and election to cause
      the Property to be sold,  which notice Trustee or Beneficiary  shall cause
      to be duly filed for record.

      B. If Trustor  shall at any time fail to perform or comply with any of the
      Obligations  under any of the Loan Documents or any other  agreement that,
      under the terms of this Deed of Trust,  Trustor is  required  to  perform,
      then  Beneficiary  may,  in its sole  discretion:  (i)  make any  payments
      hereunder  or  thereunder  payable  by Trustor  and take out,  pay for and
      maintain  any of the  insurance  policies  provided for herein or therein;
      and/or  (ii)  after the  expiration  of any  applicable  grace  period and
      subject to Trustor's right of contest of certain Obligations  specifically
      granted  hereby,  perform  any such other acts  thereunder  on the part of
      Trustor to be performed and enter upon the Property for such purpose.

      C. Should  Beneficiary elect to foreclose by exercise of the power of sale
      herein contained,  Beneficiary shall notify Trustee and shall deposit with
      Trustee this Deed of Trust and the Note and such  receipts and evidence of
      expenditures made and secured hereby as Trustee may require.  Upon receipt
      of such  notice from  Beneficiary,  Trustee  shall  cause to be  recorded,
      published  and  delivered to Trustors such notice of default and notice of
      sale as then  required  by law and by this Deed of Trust.  Trustee  shall,
      without  demand  on  Trustors,  after  lapse  of such  time as may then be
      required by law and after  recordation of such notice of default and after
      notice of sale having been given as required by law,  sell the Property at
      the time and place of sale fixed by it in said notice of sale, either as a
      whole,  or in  separate  lots or  parcels  or items as  Beneficiary  shall
      determine,  and in such  order as  Beneficiary  may  determine,  at public
      auction  to the  highest  bidder  for cash in lawful  money of the  United
      States  payable  at the  time  of  sale.  Trustee  shall  deliver  to such
      purchaser  or  purchasers  thereof its good and  sufficient  deed or deeds
      conveying  the  property so sold,  but without any  covenant or  warranty,
      express or  implied.  The  recitals  in such deed of any  matters or facts
      shall  be  conclusive  proof  of the  truthfulness  thereof.  Any  Person,
      including Trustor,  Trustee or Beneficiary,  may purchase at such sale and
      Trustor hereby covenants to warrant and defend the title of such purchaser
      or purchasers. After deducting all costs, fees and expenses of Trustee and
      of this Trust,  including  costs of evidence of title in  connection  with
      sale, Trustee shall apply the proceeds of sale in the following  priority,
      to payment of: (i) first,  all sums expended  under the terms hereof,  not
      then repaid,  with accrued  interest at the Secondary  Interest Rate; (ii)
      second,  all other sums then secured hereby;  and (iii) the remainder,  if
      any, to the person or persons legally entitled  thereto.  Beneficiary may,
      in its sole discretion, designate the order in which the Property shall be
      offered  for sale or sold  through a single  sale or  through  two or more
      successive  sales, or in any other manner  Beneficiary  deems to be in its
      best  interest.  If  Beneficiary  elects  more  than  one  sale  or  other
      disposition of the Property,  Beneficiary may at its option cause the same
      to be conducted simultaneously or successively, on the same day or at such
      different days or times and in such order as Beneficiary may deem to be in
      its best interests,  and no such sale shall terminate or otherwise  affect
      the lien of this Deed of Trust on any part of the  Property  not then sold
      until all Indebtedness  secured hereby has been fully paid. If Beneficiary
      elects to  dispose of the  Property  through  more than one sale,  Trustor
      shall pay the costs and  expenses of each such sale of its interest in the
      Property and of any  proceedings  where the same may be made.  Trustee may
      postpone  the  sale  of  all  or  any  part  of  the  Property  by  public
      announcement  at such  time  and  place of  sale,  and  from  time to time
      thereafter may postpone such sale by public announcement at the time fixed
      by the preceding  postponement,  and without further notice make such sale
      at the  time  fixed by the  last  postponement;  or  Trustee  may,  in its
      discretion,  give a new notice of sale.  Beneficiary  may rescind any such
      notice of default at any time before  Trustee's sale by executing a notice
      of rescission and recording the same. The recordation of such notice shall
      constitute a cancellation  of any prior  declaration of default and demand
      for sale and of any  acceleration of maturity of Indebtedness  affected by
      any prior declaration or notice of default. The exercise by Beneficiary of
      the right of rescission  shall not constitute a waiver of any default then
      existing or subsequently  occurring, or impair the right of Beneficiary to
      execute other  declarations  of default and demand for sale, or notices of
      default  and of election to cause the  Property to be sold,  or  otherwise
      affect the Note or this Deed of Trust,  or any of the rights,  obligations
      or remedies of Beneficiary or Trustee hereunder.

      D. In the event of a sale of the Property,  or any part  thereof,  and the
      execution  of a deed  therefor,  the recital  therein of  default,  and of
      recording  the notice of default and notice of sale,  and of the elapse of
      the required time (if any) between the  recording  and the notice,  and of
      the  giving  of notice of sale,  and of a demand  by  Beneficiary,  or its
      successors or assigns,  that such sale should be made, shall be conclusive
      proof of such default, recording,  election, elapse of time, and giving of
      such notice,  and that the sale was  regularly and validly made on due and
      proper demand by Beneficiary,  its successors or assigns. Any such deed or
      deeds with such recitals therein shall be effective and conclusive against
      Trustor,  its successors and assigns,  and all other Persons.  The receipt
      for the purchase  money  recited or contained in any deed  executed to the
      purchaser as aforesaid  shall be  sufficient  discharge to such  purchaser
      from all  obligations  to see to the proper  application  of the  purchase
      money.

      E. All  remedies of  Beneficiary  provided for herein are  cumulative  and
      shall be in addition to any and all other rights and remedies  provided in
      the other Loan  Documents or by law,  including  any right of offset.  The
      exercise of any right or remedy by Beneficiary  hereunder shall not in any
      way  constitute  a cure or waiver of default  hereunder  or under the Loan
      Documents,  or invalidate  any act done pursuant to any notice of default,
      or prejudice Beneficiary in the exercise of any of its rights hereunder or
      under the Loan Documents.

      F. All sums expended by Trustee or  Beneficiary  in the exercise of any of
      their  rights or  remedies  under this Deed of Trust,  and all  reasonable
      costs  and  expenses  incurred  in  connection   therewith  shall  (i)  be
      immediately  due and  payable  on  demand,  (ii)  accrue  interest  at the
      Secondary  Interest Rate from the date of expenditure by Beneficiary,  and
      (iii) be added to the Indebtedness and secured by the Loan Documents prior
      to any right, title or interest in or claim upon the Property attaching or
      accruing subsequent to the lien of this Deed of Trust.

                                    ARTICLE 7
                      SECURITY AGREEMENT AND FIXTURE FILING

7.1. GRANT OF SECURITY INTEREST. Trustor hereby grants to Beneficiary a security
interest  in and to all  Trustor's  right,  title  and  interest  now  owned  or
hereafter acquired in and to the Personalty and the Fixtures (collectively,  the
"Collateral").

7.2.  REMEDIES.  This Deed of Trust  constitutes a security  agreement under the
California  Uniform  Commercial  Code with  respect to the  Collateral  in which
Beneficiary is hereby granted a security interest. In addition to the rights and
remedies  provided under this Deed of Trust,  Beneficiary  shall have all of the
rights and remedies of a secured party under the California  Uniform  Commercial
Code as well as all other  rights and  remedies  available  at law or in equity.
Trustor shall execute and deliver on demand,  and  irrevocably  constitutes  and
appoints  Beneficiary the  attorney-in-fact of Trustor to, at Trustor's expense,
execute,  deliver  and,  if  appropriate,  to file with the  appropriate  filing
officer or office,  such  instruments as  Beneficiary  may request or require in
order to impose,  perfect or continue  the  perfection  of, the lien or security
interest  created  hereby.   Upon  the  occurrence  of  any  Event  of  Default,
Beneficiary  shall  have the right (i) to cause any of the  Collateral  which is
personal  property  to be sold at any one or more  public  or  private  sales as
permitted  by  applicable  law  and  to  apply  the  proceeds   thereof  to  the
Indebtedness  or the  satisfaction  of any  Obligation  and (ii) to apply to the
Indebtedness or the satisfaction of any Obligation any Collateral which is cash,
negotiable  documents or chattel paper. Any such disposition may be conducted by
an employee or agent of  Beneficiary or Trustee.  Any Person,  including both of
Trustor and  Beneficiary,  shall be eligible to purchase any part or all of such
Personalty at any such disposition.

7.3. EXPENSES. Expenses of retaking, holding, preparing for sale, selling or the
like,  pertaining to the Collateral  shall be borne by Trustor and shall include
Beneficiary's  and  Trustee's  reasonable  attorneys'  fees and  legal  expenses
(including court costs,  expert witness fees,  document  reproduction  expenses,
costs  of  exhibit  preparation,  courier  charges,  postage  and  communication
expenses). Trustor, upon demand of Beneficiary shall assemble the Collateral and
make it available to Beneficiary at the Property, a place which is hereby deemed
to be reasonably  convenient to Beneficiary and Trustor.  Beneficiary shall give
Trustor at least ten (10) days'  prior  written  notice of the time and place of
any public  sale or other  disposition  of the  Collateral  or of the time after
which any private sale or any other intended disposition is to be made. Any such
notice sent to Trustor in the manner  provided for the mailing of notices herein
is hereby deemed to be reasonable notice to Trustor.

7.4. FIXTURE FILING. This Deed of Trust covers certain goods which are or are to
become  fixtures  related to the Land and constitutes a fixture filing under the
California  Uniform  Commercial Code with respect such goods executed by Trustor
as debtor in favor of Beneficiary as secured party.

7.5. WAIVERS. Trustor waives (i) any right to require Beneficiary to (A) proceed
against any Person,  (B) proceed against or exhaust any Collateral or (C) pursue
any other  remedy in its power;  and (ii) any  defense  arising by reason of any
disability or other defense of Trustor or any other Person,  or by reason of the
cessation  from any cause  whatsoever  of the  liability of Trustor or any other
Person.  Until the Indebtedness  shall have been paid in full, Trustor shall not
have any right to  subrogation,  and  Trustor  waives any right to  enforce  any
remedy  which  Beneficiary  now has or may  hereafter  have  against  Trustor or
against any other Person and waives any benefit of and any right to  participate
in any Collateral or security whatsoever now or hereafter held by Beneficiary.

If and to the extent that any Trustor is or may ever be deemed to be a guarantor
of any Obligations of any of the other Trustors,  each Trustor hereby waives all
rights and defenses arising out of an election of remedies by Beneficiary,  even
though that election of remedies, such as a nonjudicial foreclosure with respect
to security for a guaranteed  obligation,  has extinguished  Trustor's rights of
subrogation and reimbursement against the principal, if any, by the operation of
Section 580d of the Code of Civil  Procedure or otherwise.  Notwithstanding  the
foregoing,  and in addition thereto and without limiting the generality thereof,
Trustor hereby absolutely and irrevocably waives any and all (1) rights which it
may have or may now or hereafter acquire by way of subrogation, reimbursement or
indemnity against any or all of the other Trustors by virtue of any payment made
under the Loan  Documents or otherwise  in  connection  with the Loan and/or the
Property,  and (2)  other  claims  or  rights  against  any or all of the  other
Trustors relating to the Loan Documents or the Obligations.

    TRUSTOR ACKNOWLEDGES AND AGREES THAT PURSUANT TO THE FOREGOING PARAGRAPH, IT
HAS  WAIVED,  AMONG  OTHER  SPECIFIC  RIGHTS  THAT MAY BE  GRANTED TO TRUSTOR ON
ACCOUNT OF ANY STATUS  TRUSTOR MAY BE DEEMED TO HAVE AS A SURETY OR GUARANTOR OF
ANOTHER  TRUSTOR  AT LAW OR IN  EQUITY,  ITS  RIGHTS,  IF ANY,  TO  SUBROGATION,
REIMBURSEMENT  AND/OR INDEMNITY  AGAINST ANY OR ALL OF THE OTHER TRUSTORS.  SUCH
WAIVER INCLUDES A WAIVER OF TRUSTOR'S RIGHTS THROUGH SUBROGATION,  AFTER PAYMENT
MADE BY SUCH TRUSTOR UNDER THE LOAN  DOCUMENTS,  TO BE  SUBSTITUTED  IN PLACE OF
BENEFICIARY  WITH RESPECT TO THE OBLIGATIONS OF THE OTHER TRUSTORS SUCH THAT THE
TRUSTOR COULD SUCCEED TO BENEFICIARY'S RIGHTS, REMEDIES AND/OR SECURITY RELATING
TO SUCH  OBLIGATIONS  AND ASSERT A CLAIM  AGAINST  THE OTHER  TRUSTORS.  CERTAIN
AUTHORITIES  HAVE  DETERMINED  THAT,  IN THE  ABSENCE  OF AN  EFFECTIVE  WAIVER,
PARTICULAR ACTIONS OF A LENDER THAT IMPAIR OR DESTROY A GUARANTOR'S  SUBROGATION
RIGHTS COULD PROVIDE A GUARANTOR  WITH A DEFENSE TO THE PAYMENT AND  PERFORMANCE
OF ITS OBLIGATIONS UNDER ITS GUARANTY. BY WAY OF EXAMPLE, BUT NOT OF LIMITATION,
COURTS HAVE HELD THAT, ABSENT AN EFFECTIVE WAIVER, A GUARANTOR MAY BE EXONERATED
FROM ITS  OBLIGATIONS  UNDER A GUARANTY IF A LENDER  COMPROMISES OR EXTINGUISHES
SUCH GUARANTOR'S SUBROGATION RIGHTS BY ELECTING TO FORECLOSE NON-JUDICIALLY,  BY
POWER OF SALE, ON REAL PROPERTY  SECURITY THEREBY INVOKING THE DEFICIENCY BAR OF
CALIFORNIA  CODE OF CIVIL  PROCEDURE  SECTION  580D.  TRUSTOR  AGREES  THAT SUCH
DEFENSES  ARE  INAPPLICABLE  TO  TRUSTOR  AS A  POSSIBLE  GUARANTOR  IN LIGHT OF
TRUSTOR'S  IRREVOCABLE  WAIVER OF SUBROGATION,  REIMBURSEMENT  AND/OR  INDEMNITY
RIGHTS  AGAINST  ANY OR ALL OF THE OTHER  TRUSTORS  SET  FORTH IN THE  FOREGOING
PARAGRAPH AND THAT NO ACTION BY BENEFICIARY IN ENFORCING ITS RIGHTS AND REMEDIES
AGAINST  ANY OR ALL OF  THE  OTHER  TRUSTORS  OR  OTHERWISE  MAY  COMPROMISE  OR
EXTINGUISH  SUCH RIGHTS BECAUSE EACH SUCH RIGHT HAS BEEN  IRREVOCABLY  WAIVED BY
TRUSTOR HEREUNDER.  TRUSTOR HEREBY ACKNOWLEDGES THAT IT HAS BEEN NOTIFIED OF THE
NATURE  OF ALL OF ITS  RIGHTS  AND  DEFENSES  AS A  POSSIBLE  GUARANTOR  AND HAS
KNOWINGLY AND WITH THE ADVICE OF LEGAL  COUNSEL  WAIVED SUCH RIGHTS AND DEFENSES
AS SET FORTH  HEREIN.  EACH OF THE  WAIVERS  CONTAINED  HEREIN  WERE  SEPARATELY
BARGAINED FOR.

                                         INITIALS: __________

                                    ARTICLE 8
                 ASSIGNMENT OF RENTS AND PROCEEDS AND AGREEMENTS

8.1.  ASSIGNMENT OF RENTS AND PROCEEDS.  Trustor absolutely and  unconditionally
assigns and  transfers the Rents and Proceeds to  Beneficiary,  whether now due,
past due or to become due, and gives to and confers upon  Beneficiary the right,
power and  authority to collect such Rents and  Proceeds,  and apply the same to
the  Indebtedness or the  satisfaction of any  Obligation.  Trustor  irrevocably
appoints  Beneficiary  its agent to, at any time,  demand,  receive  and enforce
payment, to give receipts, releases and satisfactions, and to sue, either in the
name of Trustor or in the name of Beneficiary,  for all such Rents and Proceeds.
Neither the  foregoing  assignment of Rents and Proceeds to  Beneficiary  or the
exercise  by  Beneficiary  of any of its rights or  remedies  under this Deed of
Trust  shall  be  deemed  to make  Beneficiary  a  "mortgagee-in-possession"  or
otherwise  responsible  or liable in any manner with  respect to the Property or
the use,  occupancy,  enjoyment or operation of all or any part thereof,  unless
and until Beneficiary,  in person or by its own agent, assumes actual possession
thereof,  nor shall  appointment  of a Receiver for the Property by any court at
the request of  Beneficiary  or by agreement  with Trustor or the entering  into
possession  of the  Property by such  Receiver be deemed to make  Beneficiary  a
"mortgagee-in-possession"  or otherwise responsible or liable in any manner with
respect to the Property or the use,  occupancy,  enjoyment or operation thereof.
Concurrently  with the  execution of this Deed of Trust,  Trustor has  executed,
delivered and recorded the Assignment of Leases in favor of Beneficiary.  In the
event of any  inconsistency  between the terms and  provisions of this ARTICLE 8
and the terms and  provisions  of the  Assignment  of Leases,  the latter  shall
control.

8.2. ASSIGNMENT OF AGREEMENTS.  Trustor hereby sells, assigns,  transfers,  sets
over and delivers to Beneficiary all of Trustor's  right,  title and interest in
and to any and all agreements,  contracts, reports, surveys, plans, drawings and
governmental approvals whatsoever pertaining to the operation of the Property or
to the construction of the Improvements, as the same may be amended or otherwise
modified  from time to time  (collectively,  the  "Agreements").  The  foregoing
assignment  encompasses  the  right  of  Trustor  to  (i)  terminate  any of the
Agreements,  (ii)  perform or compel  performance  and  otherwise  exercise  all
remedies under the Agreements,  and (iii) collect and receive all sums which may
become due Trustor or which Trustor may now or shall  hereafter  become entitled
to demand or claim, under the Agreements.

8.3.  REVOCABLE  LICENSE.  Notwithstanding  anything to the  contrary  contained
herein or in the  Note,  so long as no Event of  Default  shall  have  occurred,
Trustor  shall have a license to collect  all Rents and  Proceeds  and all other
sums which may become  payable to  Trustor  under the  Agreements,  and to first
apply the same to the payment or performance of the Obligations as and when due.
Upon the  occurrence  of (i) the first Event of Default,  and  continuing  until
twelve (12)  consecutive  calendar  months have elapsed  following  cure of such
Event of Default,  and (ii) any subsequent Event of Default,  Beneficiary  shall
have the right,  on written  notice to Trustor,  (A) to terminate and revoke the
license  herein  granted to Trustor,  and (B) then or thereafter to exercise and
enforce any and all of its rights and remedies  provided in this ARTICLE 8 or by
law or at equity.

8.4.  NONRESPONSIBILITY.  The acceptance by Beneficiary of the assignments  with
all the rights,  powers,  privileges and authority so granted shall not obligate
Beneficiary  to assume any  obligations  in respect of the Rents and Proceeds or
under the  Agreements  or take any action  thereunder  or to expend any money or
incur any expense or perform or discharge any  obligation,  duty or liability in
respect  of the Rents and  Proceeds  or under the  Agreements  or to assume  any
obligation or responsibility for the nonperformance of the provisions thereof by
Trustor.

                                    ARTICLE 9
                                  MISCELLANEOUS

9.1. SUCCESSOR TRUSTEE.  Beneficiary may remove Trustee or any successor trustee
at any time or times and  appoint a  successor  trustee by  recording  a written
substitution  in each county  where the  Property  is  located,  or in any other
manner permitted by law.

9.2.  NO WAIVER.  No failure by  Beneficiary  to insist  upon  strict,  full and
complete  (i)  payment  when  due of any  portion  of the  Indebtedness  or (ii)
performance  of any  Obligation,  nor  failure to  exercise  any right or remedy
hereunder, shall constitute a waiver of any such failure to pay or breach of any
such Obligation, or of the later exercise of such right or remedy.

9.3.  ABANDONMENT.  Any and all Personalty that upon foreclosure of the Property
is owned by Trustor and is used in connection with the operation of the Property
shall be deemed at the option of  Beneficiary to have become on such date a part
of the Property and abandoned to Beneficiary in its then condition.

9.4. NOTICES. All notices or other written communications hereunder or under any
other Loan  Documents  shall be given in writing  (i) in person or by  facsimile
transmission with receipt acknowledged,  (ii) by overnight delivery with Federal
Express or another comparable  overnight courier service,  or (iii) by mail sent
by registered or certified  mail,  postage  prepaid,  return receipt  requested,
addressed as follows:

      If to Trustor:      Mission West Properties LP
                          10050 Bandley Drive
                          Cupertino, CA  95014
                          Attn: Mr. Carl E. Berg

      If to Trustee:      Financial Title Company
                          701 Miller Street
                          San Jose, California 95110

      If to Beneficiary:  The Prudential Insurance Company of America
                          Four Embarcadero Center, Suite 2700
                          San Francisco, California 94111
                          Attention: Vice President, Mortgage Capital

      and:                The Prudential Insurance Company of America
                          Four Embarcadero Center, Suite 2700
                          San Francisco, California  94111
                          Attention: Regional Counsel

      With a copy to:     Cassidy, Cheatham, Shimko & Dawson, P.C.
                          20 California Street, Suite 500
                          San Francisco, CA 94111
                          Attention: Stephen K. Cassidy, Esq.

The notice  address  of the  parties  set forth  above may be changed by written
notice  given  hereunder.  All  notices  under  this  Deed of Trust  shall be in
writing,  shall be properly addressed and shall be sent by personal delivery, by
United  States Mail  (registered,  certified,  or Express Mail,  return  receipt
requested and postage prepaid), or by courier delivery service. All such notices
shall be  considered  delivered:  (i) if  personally  delivered,  on the date of
delivery;  (ii) if sent by United States Mail in the manner prescribed above, on
the date shown on the return  receipt for  acceptance or rejection;  or (iii) if
sent by  courier  delivery  service,  on the  date of  delivery  as shown by the
written delivery record of such service.

9.5. SEVERABILITY. If any provision hereof or of any other Loan Document is held
unenforceable  or void,  that  provision  shall  be  deemed  severable  from the
remaining  provisions and in no way affect the validity of this Deed of Trust or
any other Loan Document, except that if such provision relates to the payment of
any monetary sum, then Beneficiary may, at its option,  declare the Indebtedness
immediately due and payable.

9.6.  JOINDER OF FORECLOSURE.  Should  Beneficiary  hold any other or additional
security for the performance of the Obligations,  its sale or foreclosure,  upon
any default in such performance,  in the sole discretion of Beneficiary,  may be
prior to, subsequent to, or joined or otherwise contemporaneous with any sale or
foreclosure hereunder.

9.7.  GOVERNING  LAW.  This Deed of Trust shall be governed by and  construed in
accordance with the laws of the State of California.

9.8.  SUBORDINATION.  At the option of  Beneficiary,  exercised  in its sole and
absolute  discretion,  this Deed of Trust and/or any other Loan Document,  shall
become  subject  and  subordinate  in whole or in part (but not with  respect to
priority  of  entitlement  to  any  insurance  proceeds,   damages,  awards,  or
compensation  resulting from damage to the Property or  condemnation or exercise
of power of eminent domain), to any and all contracts of sale and/or any and all
Leases upon the execution by Beneficiary  and recording  thereof in the Official
Records  of the  county  where the  affected  Land is  located  of a  unilateral
declaration to that effect.  Beneficiary  may require the issuance of such title
insurance  endorsements  to  the  title  policy  in  connection  with  any  such
subordination as Beneficiary,  in its reasonable  judgment,  shall determine are
appropriate,  and Trustor  shall pay any cost or expense  incurred in connection
with the issuance thereof.

9.9.  WAIVER OF STATUTE  OF  LIMITATIONS  AND  RIGHTS TO TRIAL BY Jury.  Trustor
hereby waives, to the full extent allowed by law, the right to plead any statute
of limitations as a defense to any  Obligations and the right to a jury trial in
any action under or relating to the Loan Documents.

9.10.  ENTIRE  AGREEMENT.  The  Loan  Documents  and  the  Hazardous  Substances
Agreement set forth the entire  understanding  between  Trustor and  Beneficiary
relative  to the Loan and the same  shall  not be  amended  except  by a written
instrument  duly  executed by each of Trustor  and  Beneficiary.  The  foregoing
notwithstanding,  the terms and the conditions of the Application  shall survive
the funding of the Loan, but in the event of any conflict between the provisions
of the Application,  any of the other Loan Documents or the Hazardous Substances
Agreement,  except as otherwise  specifically provided herein, the terms of such
other Loan Documents and Hazardous Substances Agreement shall control.

9.11.  COPIES.  Trustor  will  promptly  give to  Beneficiary  copies of all (i)
notices of violation  relating to the Property  that Trustor  receives  from any
governmental agency or authority, and (ii) notices of default that Trustor shall
give or receive under any agreement that Trustor covenants to perform hereunder.

9.12.  PERSONALTY  SECURITY  INSTRUMENTS.  If  Beneficiary  at  any  time  holds
additional security for any obligations secured hereby, it may enforce the terms
thereof or otherwise  realize  upon the same,  at its option,  either  before or
concurrently  herewith  or after a sale is made  hereunder,  and may  apply  the
proceeds upon the  Indebtedness  without  affecting the status of or waiving any
right to exhaust all or any other  security,  including the security  hereunder,
and  without  waiving  any  breach  or  default  or any  right or power  whether
exercised hereunder or contained herein or in any such other security.

9.13. SUITS TO PROTECT  PROPERTY.  Trustor shall appear in and defend any action
or proceeding  purporting to affect the security of the Deed of Trust, any other
Loan Documents, or of any additional or other security for the Obligations,  the
interest of Beneficiary or the rights,  powers and duties of Trustee  hereunder;
and shall  pay all costs and  expenses,  including  cost of  evidence  of title,
reasonable   attorneys'  fees,  court  costs,   expert  witness  fees,  document
reproduction expenses,  costs of exhibit preparation,  courier charges,  postage
and  communication  expenses,  in any  action  or term,  covenant  or  condition
proceeding in which  Beneficiary  and/or  Trustee may appear or be made a party,
including foreclosure or other proceeding commenced by those claiming a right to
any part of the  Property in any action to  partition  or condemn all or part of
the Property,  whether or not pursued to final judgment,  and in any exercise of
the  power  of  sale  contained  herein,  whether  or not the  sale is  actually
consummated.  In any such action or  proceeding in which  Beneficiary  is made a
party,  Beneficiary may at its option defend such action,  and all costs of such
defense,  including all court costs and reasonable attorneys' fees, court costs,
expert  witness  fees,  document   reproduction   expenses,   costs  of  exhibit
preparation, courier charges, postage and communication expenses, shall be borne
and paid by Trustor.

9.14. CHARGES FOR STATEMENTS.  Trustor shall pay Beneficiary's charge, up to the
maximum  amount  permitted by law,  for any such  statement.  Beneficiary  shall
provide to Trustor  any  statement  requested  by Trustor  that  Beneficiary  is
required to deliver to Trustor under applicable law.

9.15. USURY. In the event that Beneficiary, or a court of competent jurisdiction
in a final, non-appealable judgment, determines that any charge, fee or interest
paid or agreed to be paid in connection  with the Loan may, under the applicable
usury laws, cause the interest rate on the Loan to exceed the maximum  permitted
by law,  then such  charges,  fees or interest  shall be reduced and any amounts
actually paid in excess of the maximum interest  permitted by such laws shall be
applied by Beneficiary to reduce the outstanding  Principal Balance of the Loan.
The parties  intend that Trustor  shall not be required to pay, and  Beneficiary
shall not be entitled to collect,  interest in excess of the maximum  legal rate
permitted under the applicable usury laws.

9.16. PUBLICITY. Beneficiary, at its expense, may publicize the financing of the
Property.

9.17.  INFORMATION  REPORTING UNDER IRS SECTION 6045(E). Any information returns
or  certifications  that must be filed with the Internal  Revenue Service and/or
provided to other  parties  pursuant to Internal  Revenue Code  Section  6045(e)
shall be prepared,  filed by and sent to the appropriate  parties by Trustor. To
the extent permitted by law, Beneficiary shall have no responsibility to perform
such  services;  provided  however,  that upon demand  Trustor  shall  reimburse
Beneficiary for any costs incurred by Beneficiary in doing so and shall also pay
such fee as Beneficiary may reasonably and lawfully request.  Beneficiary shall,
where  requested  by  Trustor,  promptly  supply  Trustor  with all  information
pertaining to Beneficiary reasonably required by Trustor to prepare and file any
such return or certification.

9.18.  ERISA.

      A. Beneficiary  represents and warrants to Trustor that, as of the date of
      this Deed of Trust and  throughout  the term of the  Loan,  the  source of
      funds from which  Beneficiary  extends  the Loan is its  General  Account,
      which is subject to the claims of its general creditors under state law.

      B. Trustor  represents and warrants to Beneficiary that, as of the date of
      this  Deed of Trust  and  covenants  that,  until  the Loan and all  other
      Obligations  are paid and  performed in full,  (i) Trustor is not and will
      not become an  "employee  benefit  plan" as defined in Section 3(3) of the
      Employee  Retirement  Income  Security Act of 1974, as amended  ("ERISA"),
      which is  subject  to Title I of ERISA,  and (ii) the assets of Trustor do
      not and will not constitute "plan assets" of one or more such plans within
      the meaning of 29 C.F.R. Section 2510.3-101.

      C. Trustor  represents and warrants to Beneficiary that, as of the date of
      this Deed of Trust (i)  Trustor is not a  "governmental  plan"  within the
      meaning of Section 3(32) of ERISA and (ii) transactions by or with Trustor
      are not subject to state statutes  regulating  investment of and fiduciary
      obligations with respect to governmental plans.

      D. Trustor  shall  deliver to  Beneficiary  such  certifications  or other
      evidence  from time to time until the Loan and all other  Obligations  are
      paid and  performed  in full,  as  requested  by  Beneficiary  in its sole
      discretion,  and Trustor hereby  warrants and  represents to  Beneficiary,
      that (i)  Trustor is not an  "employee  benefit  plan" or a  "governmental
      plan";  and (ii)  Trustor  is not  subject  to state  statutes  regulating
      investments and fiduciary  obligations with respect to governmental plans;
      and (iii) one or more of the following  circumstances  is true: (A) equity
      interests in Trustor are publicly offered  securities,  within the meaning
      of 29 C.F.R. Section  2510.3-101(b)(2);  (B) less than twenty-five percent
      (25%)  of all  equity  interests  in  Trustor  are held by  "benefit  plan
      investors" within the meaning of 29 C.F.R. Section  2510.3-101(f)(2);  (C)
      Trustor  qualifies as an "operating  company" or a "real estate  operating
      company" within the meaning of 29 C.F.R. Section  2510.3-101(c) or (e); or
      (D) no equity  interest in Trustor is held  directly or  indirectly  by an
      employee benefit plan subject to ERISA.

      E. In addition  to any other  breach by Trustor of any  provision  of this
      PARAGRAPH 9.18, any of the following shall  constitute an Event of Default
      entitling  Beneficiary to exercise any and all remedies to which it may be
      entitled under the Loan Documents:  (i) the failure of any  representation
      or  warranty  made by  Trustor  under this  PARAGRAPH  9.18 to be true and
      correct  in  all  respects,   (ii)  the  failure  of  Trustor  to  provide
      Beneficiary  with the  written  certifications  and  evidence  referred to
      above, or (iii) the  consummation by Trustor of a transaction  which would
      cause the Deed of Trust or any exercise of Beneficiary's  rights under the
      Loan  Documents to constitute a non-exempt  prohibited  transaction  under
      ERISA or a violation of a state  statute  regulating  governmental  plans,
      subjecting  Beneficiary  to liability for violation of ERISA or such state
      statute.

      F.  Trustor  shall  indemnify,  protect  and defend  and hold  Beneficiary
      harmless from and against all liability,  loss,  claims,  damage,  cost or
      expense,  including  attorneys'  fees,  court costs,  expert witness fees,
      document  reproduction  expenses,  costs of exhibit  preparation,  courier
      charges,  postage and  communication  expenses,  and costs incurred in the
      investigation,  defense and  settlement  of claims and losses  incurred in
      correcting any prohibited transaction or in the sale of a prohibited loan,
      and in obtaining any individual  prohibited  transaction  exemption  under
      ERISA  that  may be  required,  in  Beneficiary's  sole  discretion,  that
      Beneficiary  may incur,  directly or indirectly,  as a result of a default
      under  PARAGRAPH  9.18.E.  This indemnity  shall survive any  termination,
      satisfaction or foreclosure of the Deed of Trust.

      G.  Anything in  PARAGRAPH  4.2 or  elsewhere in this Deed of Trust to the
      contrary  notwithstanding,  no Transfer of any direct or indirect interest
      in Trustor shall be permitted which would negate Trustor's representations
      in this  PARAGRAPH  9.18 or cause this Deed of Trust (or any  exercise  of
      Beneficiary's  rights under the Loan  Documents) to constitute a violation
      of any provision of ERISA or of any applicable state statute  regulating a
      governmental plan, as determined in the sole discretion of Beneficiary.

      H.  Anything in  PARAGRAPH  4.2 or  elsewhere in this Deed of Trust to the
      contrary  notwithstanding,  no  Transfer of the  Property or any  interest
      therein including a junior lien or leasehold interest,  shall be permitted
      which  would cause this Deed of Trust (or any  exercise  of  Beneficiary's
      rights under the Loan Documents) to constitute a violation of ERISA or any
      applicable state statute  regulating a governmental plan, as determined in
      the sole discretion of Beneficiary.

      I.  Anything in this Deed of Trust to the  contrary  notwithstanding,  not
      less than fifteen  (15) days before  consummation  of a Transfer,  Trustor
      shall obtain from the proposed  transferee or lienholder a  representation
      to Beneficiary  in form and substance  satisfactory  to  Beneficiary  that
      PARAGRAPH  9.18.D will be true after the  transfer;  and further  provided
      that any proposed  lienholder  agrees that any direct or indirect transfer
      of its lien or any  interest  herein will be  governed  by this  PARAGRAPH
      9.18.

9.19.  INDEMNIFICATION AND DEFENSE.

      A. Trustor will indemnify,  defend,  protect and hold  Beneficiary and its
      agents harmless from and against all liability, loss, claims, damage, cost
      or expense  (including  reasonable  attorneys' fees,  court costs,  expert
      witness   fees,   document   reproduction   expenses,   costs  of  exhibit
      preparation,  courier charges,  postage and  communication  expenses) that
      Beneficiary  might incur in connection with the making or administering of
      the Loan, the enforcement of any of Beneficiary's rights or remedies under
      the Loan  Documents,  by reason of any  failure of any  representation  or
      warranty  made by  Trustor  or the  failure  of  Trustor  to  perform  any
      Obligation  or by reason or in defense  of any and all claims and  demands
      whatsoever that may be asserted against  Beneficiary  arising out of or in
      connection  with the  Property  or the Loan,  but which  shall not include
      claims,  liabilities,  damages, causes of action or costs arising from (1)
      Beneficiary's  and/or  any  participating  lender's  gross  negligence  or
      willful   misconduct  or  (2)  disputes   between   Beneficiary   and  any
      participating lender not arising from neglect,  willful misconduct,  or an
      act, omission or Event of Default by Trustor.

      B. Whenever,  under any Loan  Document,  Trustor is obligated to indemnify
      and/or defend Beneficiary,  or Trustor is obligated to defend or prosecute
      any  action  or  proceeding,  then  Beneficiary  shall  have the  right to
      participate in such  prosecution or defense using counsel of Beneficiary's
      choice,  and all costs and expenses  incurred by Beneficiary in connection
      with such  participation  (including  reasonable  attorneys'  fees,  court
      costs,  expert  witness fees,  document  reproduction  expenses,  costs of
      exhibit preparation,  courier charges, postage and communication expenses)
      shall be reimbursed by Trustor to  Beneficiary.  In addition,  Beneficiary
      shall  have the right to  approve  any  counsel  retained  by  Trustor  in
      connection  with  the  prosecution  or  defense  of  any  such  action  or
      proceeding  by Trustor.  Trustor shall give notice to  Beneficiary  of the
      initiation  of all  proceedings  prosecuted  or required to be defended by
      Trustor,  or which are  subject  to  Trustor's  indemnity  and/or  defense
      obligations,  under  this Deed of Trust,  promptly  after the  receipt  by
      Trustor of notice of the existence of any such proceeding, but in no event
      later than five (5) days thereafter.

      C. Should Beneficiary incur any liability,  loss, claim,  damage,  cost or
      expense required to be reimbursed by Trustor to Beneficiary hereunder, the
      amount thereof with interest thereon at the Secondary  Interest Rate shall
      constitute  part of the  Indebtedness,  shall be payable  by Trustor  upon
      demand and shall be secured by this Deed of Trust.

9.20.  DESTRUCTION OF NOTE. Trustor shall, if the Note is mutilated or destroyed
by any cause  whatsoever,  or otherwise lost or stolen and regardless of whether
due to the act or neglect of  Beneficiary  or  Trustee,  execute  and deliver to
Beneficiary in substitution  therefor a duplicate promissory note containing the
same terms and  conditions as the Note,  within ten (10) days after  Beneficiary
notifies Trustor of any such mutilation, destruction, loss or theft of the Note.
In such event,  Beneficiary shall be responsible for any payments Trustor may be
legally  required to make to any holder of the  original  promissory  note after
Trustor  has paid  Beneficiary  on a duplicate  note,  provided,  however,  that
Trustor  shall make no such  payments on the  original  promissory  note without
Beneficiary's  written consent and Trustor shall give Beneficiary written notice
of any request that may be made of Trustor to make such payment(s) within thirty
(30) days after Trustor has received any such request.

9.21. HEIRS AND ASSIGNS.  Subject to the restrictions on Transfers  contained in
this Deed of Trust,  this Deed of Trust and all other Loan  Documents  apply to,
inure to the benefit of, and bind all parties  hereto and thereto,  their heirs,
legatees, devisees, administrators, executors, successors and assigns.

9.22.  INTERPRETATION.  When the identity of the parties or other  circumstances
make it  appropriate,  the masculine  gender shall  include the feminine  and/or
neuter, and the singular number shall include the plural.  Specific  enumeration
of rights, powers and remedies of Trustee and Beneficiary and of acts which they
may do and of acts  Trustor  must do or not do shall  not  exclude  or limit the
general.  The headings of each Article and Paragraph are for  convenience and do
not limit or construe the contents of any provision  hereof.  The  provisions of
the Loan Documents and the Hazardous  Substances Agreement shall be construed as
a whole according to their common meaning, not strictly for or against any party
and consistent  with the provisions  herein  contained,  in order to achieve the
objectives  and  purposes  of such  documents.  Each party and its  counsel  has
reviewed and revised the Loan Documents and the Hazardous  Substances  Agreement
and  agree  that  the  normal  rule  of  construction  to the  effect  that  any
ambiguities are to be resolved  against the drafting party shall not be employed
in the  interpretation  of such document.  The use in the Loan Documents and the
Hazardous Substances Agreement of the words "including",  "such as", or words of
similar import when following any general term, statement or matter shall not be
construed  to limit  such  statement,  term or matter to the  specific  items or
matters,  whether or not language of non-limitation such as "without limitation"
or "but not  limited  to",  or words of similar  import are used with  reference
thereto,  but rather shall be deemed to refer to all other items or matters that
could reasonably fall within the broadest possible scope of such statement, term
or  matter.  The term  "Trustor"  shall  be  deemed  to refer to each and  every
Trustor, both individually and collectively,  when more than one Trustor exists,
and to the original Trustor, and its or their successors and assigns (whether or
not such  successor  or assign  assumed  the  Obligations  hereunder);  the term
"Beneficiary"  includes  the  Beneficiary  named  herein or any future  owner or
holder, including pledgee and participants, of the Note, or any other instrument
secured hereby, or any participation  therein;  and the term "Trustee"  includes
the original  Trustee and its  successors  and assigns.  The  references  to the
"Property"  shall be deemed to refer to all or any portion of the  Property  and
any interest  therein.  References to "foreclosure" and related phrases shall be
deemed  references to the  appropriate  procedure in connection  with  Trustee's
private  power  of  sale as well as any  judicial  foreclosure  proceeding  or a
conveyance in lieu of foreclosure.

9.23. INFORMATION TO THIRD PERSONS. If, at any time, Beneficiary desires to sell
or transfer, or grant a participation interest in, all or any portion of, or any
interest in, the Note or any other Loan  Document to any Person,  Trustor  shall
furnish in a timely  manner any and all  financial  information  concerning  the
Property and Leases,  and concerning  Trustor,  requested by Beneficiary or such
Person in connection with any such sale or transfer.

9.24.  COMMINGLING  OF  FUNDS.  Any  and  all  sums  collected  or  retained  by
Beneficiary   under  any  of  the  Loan  Documents   (including   insurance  and
condemnation  proceeds  and any  amounts  paid by Trustor to  Beneficiary  under
PARAGRAPH 3.4 hereof),  shall not be deemed to be held in trust, and Beneficiary
may commingle  such funds or proceeds  with its general  assets and shall not be
liable for the payment of any  interest or other return  thereon,  except to the
extent otherwise required by law.

9.25. CERTAIN OBLIGATIONS  UNSECURED.  Notwithstanding  anything to the contrary
set forth  herein  or any of the Loan  Documents,  this  Deed of Trust  does not
secure  the  following  obligations  (the  "Unsecured  Obligations"):   (i)  any
obligations  evidenced by or arising under the Hazardous  Substances  Agreement,
(ii) any other  obligations  in this  Deed of Trust or in any of the other  Loan
Documents to the extent that such other obligations  relate  specifically to the
presence on the Property of  Hazardous  Materials  (as defined in the  Hazardous
Substances  Agreement)  and are the same or have the same  effect  as any of the
obligations  evidenced by or arising under the Hazardous  Substances  Agreement,
and (iii) any obligations arising under the Certificate  Regarding  Distribution
of Proceeds and Indemnity  Agreement.  Any breach or default with respect to the
Unsecured   Obligations   shall  constitute  an  Event  of  Default   hereunder,
notwithstanding the fact that such Unsecured Obligations are not secured by this
Deed of  Trust.  Nothing  in this  section  shall,  in  itself,  impair or limit
Beneficiary's right to obtain a judgment in accordance with applicable law after
foreclosure for any deficiency in recovery of all  obligations  that are secured
by this Deed of Trust following foreclosure.

9.26 COSTS AND FEES.  All costs,  fees and expenses  incurred by  Beneficiary in
making,  administering  or collecting the Loan (including those of Beneficiary's
legal  counsel and  consultants,  court costs,  expert  witness  fees,  document
reproduction expenses, costs of exhibit preparation,  courier charges,  postage,
communication  expenses,  costs in  connection  with any  inspections,  reports,
tests,  inquiries and reviews,  condemnation  proceedings,  endorsements  to the
title policy,  actions or  proceedings in which  Beneficiary  and/or Trustee may
appear or be made a party,  foreclosure or other proceedings  commenced by those
claiming a right to any part of the Property or any action to  partition  all or
part of the Property,  whether or not pursuant to final judgment and exercise of
the  power  of  sale  contained  herein,  whether  or not the  sale is  actually
consummated)  and all sums expended by Trustee or Beneficiary in the exercise of
any of their  respective  rights or remedies under this Deed of Trust,  shall be
immediately due and payable by Trustor to Beneficiary upon demand,  shall accrue
interest at the Secondary Interest Rate from the date of expenditure until paid,
and shall be added to the  Indebtedness  secured by the Loan Documents  prior to
any right, title or interest in or claim upon the Property attaching or accruing
subsequent to the lien of this Deed of Trust.

9.27.  STANDARD OF APPROVAL;  COVENANT OF GOOD FAITH AND FAIR DEALING.  Whenever
Trustee or  Beneficiary  has been  specifically  granted a right to exercise its
business judgment,  or act, in a subjective manner,  with respect to any matter,
or the right to act in its sole and absolute discretion or sole judgment, or the
right to make a  subjective  judgment  under any  provision  of this  Agreement,
whether  or not  "objectively"  reasonable  under  the  circumstances,  any such
exercise  shall not be deemed  inconsistent  with any covenant of good faith and
fair dealing otherwise implied by law to be part of the Loan Documents.

9.28. EXHIBITS.  The following Exhibits, to which reference is made in this Deed
of Trust, are deemed incorporated into this Deed of Trust in their entirety:
           A    -    Property Description
           B    -    Eligible Transfer Properties

9.29  JOINT AND  SEVERAL  LIABILITY.  The  Obligations  are  joint  and  several
undertakings  of each of the Trustors,  and  Beneficiary may proceed against any
one or more of the Trustors  without waiving its right to proceed against any of
the other Trustors.

IN WITNESS WHEREOF, Trustors have caused this Deed of Trust to be executed as of
the day and year first above written.

                               TRUSTOR:

                               MISSION WEST PROPERTIES, L.P.,
                               a Delaware limited partnership

                               By: Mission West Properties,
                                   a California corporation, its general partner

                                       By:
                                         --------------------------------------
                                         Carl E. Berg, Chairman, President, CEO

                              [Signatures continued on succeeding page]
                              MISSION WEST PROPERTIES, L.P. I,
                              a Delaware limited partnership

                              By: Mission West Properties,
                                  a California corporation, its general partner

                                       By:
                                         --------------------------------------
                                         Carl E. Berg, Chairman, President, CEO


                               MISSION WEST PROPERTIES, L.P. II,
                               a Delaware limited partnership

                               By:Mission West Properties,
                                  a California corporation, its general partner

                                       By:
                                         --------------------------------------
                                         Carl E. Berg, Chairman, President, CEO


                               MISSION WEST PROPERTIES, L.P. III
                               a Delaware limited partnership

                               By:Mission West Properties,
                                  a California corporation, its general partner

                                       By:
                                         --------------------------------------
                                         Carl E. Berg, Chairman, President, CEO







                                    EXHIBIT A

                             (Property Description)





                                    EXHIBIT B

                         (Eligible Transfer Properties)

Each of the following  eighteen (18) properties shall be considered an "Eligible
Transfer   Property"  and   collectively   constitute  the  "Eligible   Transfer
Properties".  Single buildings that do not  individually  constitute an Eligible
Transfer  Property shall not be released unless released with the other building
or buildings together constituting one of the Eligible Transfer Properties.




            Name of Property and Location of Property/Allocated Loan

    BUILDING ADDRESS(ES)                               ZIP CODE       NRA          AMOUNT

                                                                              
1.  10300 Bubb Road                     Cupertino      95014-4165      23,400       $2,548,000.00
2.  10500 North De Anza Blvd.           Cupertino      95014-2033     211,000      $34,562,000.00
3.  1230/1250 East Arquez Ave.          Sunnyvale      94086-5401     260,000       $7,836,000.00
4.  3550/3560/3570/3580 Bassett Street  Santa Clara    95054-2738     166,663      $12,830,000.00
5.  3540/3542/3544 Bassett St.          Santa Clara    95054-2704     104,060       $7,043,000.00
6.  1135 Kern Avenue                    Sunnyvale      94086-3908      18,300       $1,434,000.00
7.  1212 Bordeaux                       Sunnyvale      94089-1202      71,800       $6,029,000.00
8.  1170 Morse                          Sunnyvale      94089-1605      34,750       $2,446,000.00
9.  450-460 National Ave.               Mountain View  94043-2238      36,100       $2,702,000.00
10. 3236 Scott Boulevard                Santa Clara    95054-3011      54,672       $4,360,000.00
11. 6311 San Ignacio                    San Jose       95119-1202      30,000       $1,788,000.00
12. 6321/6325 San Ignacio               San Jose       95119-1202     103,894       $7,380,000.00
13. 6331 San Ignacio                    San Jose       95119-1202     131,320       $8,903,000.00
14. 6341/6351 San Ignacio               San Jose       95119-1202      95,040       $5,315,000.00
15. 4949 Hellyer Ave.                   San Jose       95138-1014     200,484      $12,480,000.00
16. 4050 Starboard Drive                Fremont        94538-6402      52,232       $4,480,000.00
17. 45700 Northport Loop East           Fremont        94538-6476      47,570       $4,248,000.00
18. 45738 Northport Loop West           Fremont        94538-6476      44,256       $3,616,000.00









STATE OF CALIFORNIA                )
                                   )ss.
COUNTY OF ________________________ )



     On   this   __   day   of    _____________________,    1998,   before   me,
______________________,  a  notary  public  in and for  said  state,  personally
appeared _________________________________, personally known to me (or proved to
me on the basis of  satisfactory  evidence) to be the  person(s)  whose  name(s)
is/are  subscribed to the within  instrument and  acknowledged to me that he/she
executed  the same in  his/her  authorized  capacity(ies),  and that by  his/her
signature(s) on the instrument the person(s), or the entity upon behalf of which
the person(s), acted, executed the instrument.

     WITNESS my hand and official seal.



                                  Notary Public
                              State of California

                              My Commission Expires:__________