EXHIBIT 10.49



                                LIMITED GUARANTY


     THIS LIMITED  GUARANTY is made and given as of the 6 day of April,  2005 by
MISSION WEST PROPERTIES, INC., a Maryland corporation ("Guarantor"),  to and for
the benefit of ALLIANZ  LIFE  INSURANCE  COMPANY OF NORTH  AMERICA,  a Minnesota
corporation ("Lender").

                                  WITNESSETH :

     WHEREAS,  Lender  has agreed to make a loan (the  "Loan")  to Mission  West
Properties,  L.P., a Delaware limited partnership ("Borrower"),  in the original
principal   amount  of  TWENTY  FIVE  MILLION  EIGHT  HUNDRED  THOUSAND  DOLLARS
($25,800,000.00),  which Loan will be evidenced by a Secured Installment Note in
the original principal amount of the Loan (the "Note"), and will be secured by a
Deed of Trust,  Security  Agreement,  Fixture Filing with Absolute Assignment of
Rents (the "Deed of Trust") to create a lien on certain real  property,  and all
improvements  thereon,  located in the City of San Jose,  County of Santa Clara,
California  (the  Note,  Deed of Trust and all  other  documents  evidencing  or
securing the Loan are herein collectively called the "Security Documents"); and

     WHEREAS, to induce Lender to make the Loan, Guarantor has agreed to provide
a limited  guaranty  for the  payment  of  certain  sums due under the  Security
Documents.  The  purpose of this  Limited  Guaranty  is to specify the terms and
conditions of those limited guarantees; and

     WHEREAS,   Guarantor  acknowledges  that  it  will  receive  a  direct  and
substantial  benefit from the making of the Loan, and Guarantor  agrees that the
making of the Loan constitutes adequate  consideration and reasonably equivalent
value for the execution and delivery of this Limited Guaranty by Guarantor.

     NOW,  THEREFORE,  incorporating  the recitals of facts above, and to induce
Lender  to  make  the  Loan  to  Borrower,  and  for  other  good  and  valuable
consideration,  the  receipt  and  adequacy  of which are  hereby  acknowledged,
Guarantor agrees as follows:

     1. Guarantor hereby absolutely and  unconditionally  guarantees  payment to
Lender for payment in full of (i) all amounts  identified in  subparagraphs  (1)
through (7),  inclusive,  of Paragraph  15(b) of the Note,  and (ii) all amounts
which may become due and payable by Borrower to Lender under the  provisions  of
Paragraph 15(c) of the Note (collectively, the "Guaranteed Obligations").

     2. It is  understood  that each  limited  guaranty  herein is a guaranty of
immediate  payment in accordance  with the terms and  conditions of the Security
Documents,  and that Lender may enforce its right to immediate  payment  without
proceeding  against or joining  Borrower and without  applying or enforcing  any
security for the Loan.

     3.  Lender may assign or  transfer  this  Limited  Guaranty  and its rights
hereunder, in whole or in part, in connection with the assignment or transfer of
the Loan or an interest  therein.  The benefit of this  Limited  Guaranty  shall
automatically  pass with a transfer or  assignment by Lender or its successor or
assign of the Loan or any portion thereof to any subsequent  party to the extent
of such  party's  interest  in the Loan.  In the event of any such  transfer  or
assignment,  this  Limited  Guaranty  shall remain in full force and effect with
respect to any interest retained by Lender.  All rights and privileges of Lender
herein shall inure to the benefit of each and every assign and  successor to the
rights of  Lender,  regardless  of whether  such  assign or  successor  holds an
interest in the Loan currently with Lender,  and all references to Lender herein
shall be  deemed  to  include  every  assignee  or  successor  of  Lender or any
subsequent holder of the Loan or any portion thereof.

     4. (a) No action  Lender  may take or omit to take in  connection  with the
Loan or any security given therefor,  nor any course of dealing with Borrower or
any  representative  or employee of  Borrower,  shall  relieve  Guarantor of its
obligations  hereunder,  affect  this  Limited  Guaranty  in any way,  or afford
Guarantor any recourse against Lender. By way of example,  but not in limitation
of the foregoing,  Guarantor  hereby expressly agrees that Lender may, from time
to time and without notice to Guarantor:

          (1)  Amend,  change,  or  modify,  in whole or in part,  the  Security
     Documents;

          (2) Accelerate,  change,  extend, or renew the time for payment of the
     Note;

          (3) Waive any terms,  conditions,  or covenants of any of the Security
     Documents, or grant any extension of time or forbearance for performance of
     the same;

<PAGE>

          (4)  Compromise or settle any amount due or owing or claimed to be due
     or owing under any of the Security Documents; or

          (5) Surrender,  release, or subordinate any or all of the security for
     the Loan or accept additional or substituted security therefor.

     (b) The provisions of this Limited  Guaranty shall extend and be applicable
to all  renewals,  amendments,  extensions,  and  modifications  of the Security
Documents,  and all  references  to any  Security  Documents  shall be deemed to
include any such renewal, extension, amendment, or modification thereof.

     5. (a)  Guarantor  expressly  waives  notice of  acceptance of this Limited
Guaranty, presentment of payment, or performance of Borrower's obligations under
the  Security  Documents,  protest  and  notice of  protest,  demand,  notice of
dishonor,  notice of any and all  proceedings  to collect  amounts due under the
Security  Documents,  and to  enforce  any  security  given  for the  Loan,  and
diligence in collecting  sums due under the Loan or to any liability  under this
Limited  Guaranty.  Guarantor also waives any right to require Lender to proceed
against  Borrower,  to proceed against or exhaust any security held to guarantee
performance of Borrower's  obligations to Lender,  or to pursue any other remedy
whatsoever  available to Lender.  Guarantor expressly waives any defense arising
by reason of any disability or other defense by Borrower (other than payment and
performance of the Guaranteed Obligations),  by reason of the cessation from any
cause whatsoever of the liability of Borrower, or by reason of Lender's election
of any  remedy  against  Borrower  or  Guarantor,  or  both,  including  without
limitation  election of Lender to exercise its rights to  foreclose  the Deed of
Trust and the potential loss by Guarantor of the right to recover any deficiency
from Borrower.

     (b) Until all  indebtedness  of Borrower to Lender  shall have been paid in
full,  Guarantor  shall  have no  right  of  subrogation  as to its  obligations
hereunder, and Guarantor hereby expressly waives any right to enforce any remedy
which  Lender now has or may  hereafter  have  against  Borrower  and waives any
benefit of and any right to participate in any security now or hereafter held by
Lender.

     (c) If Borrower or Guarantor  shall at any time become  insolvent or make a
general assignment for the benefit of creditors,  or if a petition in bankruptcy
or any insolvency or  reorganization  proceeding shall be filed or commenced by,
against,  or in respect of the Borrower or any Guarantor,  such action shall not
in  any  manner  affect  the  continuing  obligations  of the  other  Guarantors
hereunder, if any.

     (d) The validity of this  Limited  Guaranty  and  obligations  of Guarantor
shall not be  terminated,  affected,  or impaired by the relief,  discharge,  or
release of any or all of the  indebtedness  by  operation  of law or  otherwise,
including, without limitation, a discharge in bankruptcy, receivership, or other
proceedings,  a disaffirmation  or rejection of the indebtedness by a trustee or
other representative in bankruptcy, a stay or other enforcement restriction,  or
any other  reduction,  modification,  impairment,  or  limitation  of any of the
indebtedness.

     6. (a) Guarantor hereby: (i) waives notice of any extension,  modification,
refunding,  amendment, addition or supplement to, deletion or departure from, or
breach  of any of the  terms of this  Limited  Guaranty  or the  other  Security
Documents or any other  agreement  that may be made relating  hereto or thereto;
(ii) waives notice of the occurrence of any default  hereunder or the occurrence
of any  default or Event of Default  under any of the  Security  Documents,  any
compromise,  release,  consent or other  action or inaction  with respect to the
collateral  granted to Lender under any of the Security  Documents or any of the
terms and provisions of the Security Documents; (iii) waives notice with respect
to any exercise or non-exercise by Lender, or any right,  power, or remedy under
or in respect of the Security Documents or any security,  lien, deposit, pledge,
or guaranty  held in  connection  with the  liabilities  of  Borrower  under the
Security  Documents;  (iv) waives any defense based upon an election of remedies
by Lender whether or not the right of Guarantor to proceed against  Borrower for
reimbursement is affected;  (v) waives,  to the extent Guarantor may lawfully do
so,  any  defense  based  upon  any  statute  or rule  which  provides  that the
obligation  of a surety must be neither  larger in amount nor in other  respects
more  burdensome  than that of the  principal;  (vi) waives any defense based on
Borrower's  waiver or  relinquishment of its right to designate which portion of
the Indebtedness  shall be satisfied by a partial  payment,  whether pursuant to
California  Civil Code Section 2822 or otherwise,  and (vii) waives all defenses
which  Borrower  may now or  hereafter  have to the  payment  of the  Guaranteed
Obligations which could otherwise be asserted by Guarantor in any defense (other
than payment) of any kind which Guarantor may now or hereafter have with respect
to any of the Security  Documents,  any other guaranty,  or any other collateral
securing the obligations under the Security Documents.

     (b)  Guarantor  waives  the  right to  require  Lender to  proceed  against
Borrower or any other person liable on the  indebtedness,  to proceed against or
exhaust any security held from  Borrower or any other  person,  or to pursue any
other remedy in Lender's  power  whatsoever,  and Guarantor  waives the right to
have the property of Borrower  first applied to the discharge of the  Guaranteed
Obligations.  Lender may, at its  election,  exercise any right or remedy it may
have  against  Borrower  or any  security  held by  Lender,  including,  without
limitation,  the  right  to  foreclose  upon any  such  security  by one or more
judicial or nonjudicial  sales,  whether or not every aspect of any such sale is
commercially reasonable, without affecting or impairing in any way the liability
of Guarantor  hereunder,  except to the extent the  indebtedness  has been paid.
Guarantor  waives  any  defense  arising  by reason of any  disability  or other
defense of  Borrower  (other  than  payment and  performance  of the  Guaranteed
Obligations) or by reason of the cessation from any cause

<PAGE>

whatsoever,  including,  without  limitation,  any  intervention  or omission by
Lender, of the liability,  either in whole or in part, of Borrower to Lender for
the  indebtedness.  Guarantor hereby waives,  to the fullest extent permitted by
law, all rights and benefits  under  Section 2809 of the  California  Civil Code
purporting  to reduce a guarantor's  obligations  in proportion to the principal
obligation, all rights and benefits under Section 580a of the California Code of
Civil Procedure  purporting to limit the amount of any deficiency  judgment that
might be  recoverable  following the occurrence of a trustee's sale under a deed
of trust on real  property,  including  the right,  if any,  to assert  that any
deficiency is limited to the difference between the "fair value" of the property
and the amount of the debt,  all rights and benefits  under  Section 580b of the
California Code of Civil  Procedure  stating that no deficiency may be recovered
on a real property  purchase  money  obligation,  all rights and benefits  under
Section  580d  of the  California  Code  of  Civil  Procedure  stating  that  no
deficiency  may be  recovered  on a note  secured  by a deed  of  trust  on real
property in case such real property is sold under the power of sale contained in
such deed of trust, if such section, or any of them, have any application hereto
or any  application to Guarantor,  and all rights and benefits under Section 726
of the  California  Code of Civil  Procedure,  including  the right,  if any, to
assert that any deficiency is limited to the difference between the "fair value"
of the  property  and the  amount of the debt.  In  addition,  Guarantor  hereby
waives,  to the fullest  extent  permitted by law, (a) any defense  arising as a
result of any election by Lender under Section 1111(b)(2) of the Bankruptcy Code
in any proceeding instituted under the Bankruptcy Code, (b) any defense based on
any  borrowing  or  grant  of a  security  interest  under  Section  364  of the
Bankruptcy  Code, (c) any defense  arising as a result of any election by Lender
under Section 9501(4) of the California Uniform Commercial Code, and (d) without
limiting the  generality of the  foregoing or any other  provision  hereof,  all
rights and  benefits  that might  otherwise  be  available  to  Guarantor  under
California  Civil Code Sections 2810,  2819,  2839, 2845, 2848, 2849, 2850, 2899
and 3433. Guarantor also makes the following waivers under California Civil Code
Section 2856:

          (1)  Guarantor  waives all rights and defenses  that the Guarantor may
     have because Borrower's debt is secured by real property. This means, among
     other things:


               (A) Lender may collect from Guarantor  without first  foreclosing
          on any real or personal property collateral pledged by Borrower.

               (B) If Lender forecloses on any real property  collateral pledged
          by Borrower:

                    i. The amount of the debt may be  reduced  only by the price
               for which that collateral is sold at the  foreclosure  sale, even
               if the collateral is worth more than the sale price.

                    ii.  Lender may collect from  Guarantor  even if Lender,  by
               foreclosing  on the real property  collateral,  has destroyed any
               right Guarantor may have to collect from Borrower.

          This is an  unconditional  and  irrevocable  waiver of any  rights and
          defenses Guarantor may have because Borrower's debt is secured by real
          property.  These rights and defenses include,  but are not limited to,
          any rights or defenses based upon Sections 580a,  580b, 580d or 726 of
          the Code of Civil Procedure.

          (2)  Guarantor  waives  all  rights  and  defenses  arising  out of an
     election of remedies by Lender, even though that election of remedies, such
     as a  non-judicial  foreclosure  with  respect to security for a guaranteed
     obligation,   has  destroyed   Guarantor's   rights  of   subrogation   and
     reimbursement against the principal by the operation of Section 580d of the
     Code of Civil Procedure or otherwise.

     (c)  Guarantor  assumes the  responsibility  for being and  keeping  itself
informed of the financial  condition of Borrower and of all other  circumstances
bearing upon the risk of nonpayment of the  indebtedness  that diligent  inquiry
would reveal,  and agrees that Lender shall have no duty to advise  Guarantor of
information  known to it regarding  such  condition  or any such  circumstances.
Guarantor  hereby  waives any  defense  to its  obligations  under this  Limited
Guaranty  based  upon any  failure  by Lender to advise or inform  Guarantor  of
Borrower's financial status.

     7. Guarantor agrees that Lender shall have no duty to disclose to Guarantor
any  information  it receives  regarding the  financial  status of the Borrower,
whether or not such  information  indicates  that the risk that Guarantor may be
required to perform  hereunder has been or may be increased.  Guarantor  assumes
full responsibility for being and keeping informed of all such matters.

     8.  The   obligations  of  Guarantor   hereunder  are  independent  of  the
obligations of Borrower,  and Lender may proceed  directly to enforce its rights
under this Limited Guaranty without  proceeding  against or joining the Borrower
and without  applying or enforcing any security for the Loan.  Guarantor  hereby
waives any rights it may have to compel  Lender to proceed  against the Borrower
or any  security  or to  participate  in any  security  for the sums  guaranteed
hereby.

     9.  Lender  shall have the right to enforce its rights  under this  Limited
Guaranty or to enforce its rights against Borrower, including without limitation
its  rights  under  the  Security  Documents,  in any  order,  and all  remedies
available to Lender shall be nonexclusive. Guarantor hereby empowers Lender, its
successors  and  assigns,  in their sole  discretion,  to exercise  any right or
remedy

<PAGE>

which they may have, including but not limited to judicial foreclosure, exercise
of rights of power of sale,  taking a deed or assignment in lieu of  foreclosure
or sale,  appointment  of a receiver to protect the security or to collect rents
and profits,  exercise of remedies against personal property,  or enforcement of
an  assignment  of  leases,  as to any  security,  whether  real,  personal,  or
intangible,  and  Guarantor  shall be liable to Lender  for any  failure of such
securities to fully satisfy the amounts  guaranteed  hereby (but in no event may
Lender have  satisfaction  in an amount greater than the full amount  guaranteed
hereby), even though any rights which Guarantor may have against the Borrower or
others may be  diminished  or  destroyed by the exercise or election to exercise
any such remedy.

     10. Guarantor hereby  authorizes  Lender,  without notice to Guarantor,  to
apply all  payments  and credits  received  from  Borrower or from  Guarantor to
payment of the Loan or in  satisfaction  of any of the covenants and  conditions
set forth in the Security Documents.

     11.  Guarantor  agrees to indemnify  Lender for,  and hold Lender  harmless
against,  all loss, cost, and expense,  including,  without limitation all court
costs and attorneys' fees (including  appellate fees, if any),  incurred or paid
by Lender in enforcing or compromising any rights under this Limited Guaranty.

     12. (a) Guarantor  shall  furnish to Lender,  within ninety (90) days after
the end of each twelve (12) month  period  selected by  Guarantor  as its fiscal
accounting (a "Fiscal  Year"),  financial  statements of Guarantor,  prepared in
accordance with generally accepted accounting  principles,  consistently applied
("GAAP").  Guarantor's annual financial statement shall be audited and certified
by an  independent  certified  public  accountant as complete and correct in all
material  respects.  Financial  statements  shall be  certified  as complete and
correct in all material respects by an officer of Guarantor. Upon the occurrence
of an Event of Default  under the Deed of Trust or under this Limited  Guaranty,
financial  statements shall be provided within ninety (90) days after the end of
each fiscal  quarter of  Guarantor  and all  financial  statements  of Guarantor
submitted to Lender shall be audited and  prepared by an  independent  certified
public  accountant.  Guarantor  agrees to keep  adequate  books and  records  of
account in accordance with GAAP.

     (b) For  purposes  of this  paragraph,  the  following  terms will have the
following meanings:

          (1)  "Capital  Lease   Obligations"   of  Guarantor   shall  mean  the
     obligations  to pay rent or other  amounts  under a lease of (or other debt
     arrangements  conveying  the right to use)  real or  personal  property  of
     Guarantor  which are  required  to be  classified  and  accounted  for as a
     capital lease or a liability on the fact of a balance sheet of Guarantor in
     accordance  with  GAAP,  and the  amount of such  obligations  shall be the
     capitalized  amount thereof in accordance with GAAP and the stated maturity
     thereof  shall be the date of the last  payment of rent or any other amount
     due under  such  lease  prior to the first  date  upon  which  lease may be
     terminated by the lessee without payment of a penalty.

          (2)  "Debt"  shall  mean  (without   duplication),   with  respect  to
     Guarantor, (i) every obligation of Guarantor for money borrowed, (ii) every
     obligation of Guarantor  evidenced by bonds,  debentures,  notes,  or other
     similar  instruments,  including  obligations  incurred in connection  with
     acquisition of property, assets or businesses,  excluding instruments which
     are  considered  equity under GAAP and any trade payments and other accrued
     current liabilities arising in the ordinary course of business, (iii) every
     currently due reimbursement obligation of Guarantor with respect to letters
     of  credit,  bankers'  acceptances  or  similar  facilities  issued for the
     account of Guarantor,  (iv) every obligation of Guarantor issued or assumed
     as the deferred  purchase price of property (but  excluding  trade accounts
     payable  and other  accrued  current  liabilities  arising in the  ordinary
     course of  business  which are not overdue by more than ninety (90) days or
     which  are  being  contested  in  good  faith),  (v)  every  Capital  Lease
     Obligation of Guarantor,  and (vi) every obligation of the type referred to
     in clauses  (i) through  (v) of another  and all  dividends  of another the
     payment of which,  in either case,  Guarantor  has  guaranteed or for which
     Guarantor is  responsible or liable,  directly or  indirectly,  as obligor,
     guarantor or  otherwise or is secured by a lien on any asset of  Guarantor,
     whether or not Guarantor has assumed such obligation.

          (3) "Gross  Assets" shall mean, at any date,  the sum of all assets of
     Guarantor (less  depreciation,  amortization and valuation reserves) which,
     in accordance with GAAP,  would be included on a balance sheet of Guarantor
     (other than any assets  which are  classified  as  intangible  assets under
     GAAP, including,  without limitation,  goodwill, patents, trademarks, trade
     names, copyrights and franchises).

          (4) "Net Worth"  shall mean,  at any date,  Gross  Assets at such date
     less the aggregate outstanding principal amount of the Debt at such date.

     (c)  Guarantor  represents,  warrants and covenants to and with Lender that
until all  indebtedness  of Borrower  to Lender  under the Loan and all sums due
under the Loan Documents have been paid in full:

          (1) Guarantor  will not, at any time,  permit its Net Worth to be less
     than TWENTY MILLION DOLLARS ($20,000,000.00).

<PAGE>

          (2) Guarantor is and, unless changed as provided below,  will continue
     to be a Maryland  corporation duly organized and validly existing under the
     laws of the State of Maryland in good standing and qualified to do business
     in  the  State  of  California.  Guarantor  may  not  change  its  form  of
     organization or state of organization  without the prior written consent of
     Lender.

     (d) Guarantor's  failure to maintain the Net Worth required herein shall an
"Event of Default" under the Deed of Trust.

     13. Guarantor's obligations hereunder shall not be assigned or delegated.

     14. This Limited  Guaranty may not be changed orally,  and no obligation of
the Guarantor can be released or waived by Lender except by a signed  writing by
an authorized officer of Lender.

     15.  Guarantor  agrees that the death or  dissolution  of any Guarantor (if
more than one  Guarantor)  shall not  terminate  this Limited  Guaranty and that
nothing shall discharge or satisfy the liability of Guarantor  hereunder  except
full payment on the conditions and in the amounts described herein.

     16.  Guarantor  hereby warrants and represents that, as of the date hereof,
there has been no material change in Guarantor's  financial  condition from that
reflected in the financial statements  previously submitted to Lender and, since
the date of such  statements,  the business,  property,  and assets of Guarantor
have not been adversely affected in any material way.

     17. This Limited  Guaranty shall be governed by and construed in accordance
with the Laws of the State of  California.  In the event that any  provision  or
clause of this Limited  Guaranty  conflicts with  applicable  law, such conflict
shall not affect other  provisions of this Limited  Guaranty  which can be given
effect without the conflicting provisions, and to this end the provisions of the
Limited Guaranty are declared to be severable.

     18. If any term or provision of this Limited  Guaranty  shall be determined
to be illegal or  unenforceable,  all other terms and  provisions  hereof  shall
nevertheless  remain  effective  and shall be  enforced  to the  fullest  extent
permitted by law.

     19. This Limited  Guaranty shall be irrevocable by Guarantor  until (i) the
entire principal amount of the Loan has been repaid to Lender, together with all
accrued  interest  and other  charges due and  payable to Lender  under any Loan
Document, including, but not limited to, the Environmental Indemnity, or (ii) an
assumption  of the Loan by a party  approved  by Lender in  accordance  with the
terms of Section 1.11(b) of the Deed of Trust.

     20. If any Guarantor shall become bankrupt or insolvent, or any application
shall be made to have any  Guarantor  declared  bankrupt  or  insolvent,  or any
Guarantor shall make an assignment for the benefit of creditors,  notice of such
occurrence or event shall be promptly furnished to Lender by such Guarantor.

     21. The rights of Lender  granted and arising  hereunder  shall be separate
and distinct and  cumulative of other powers and rights which Lender may have at
law or in equity,  and none of them shall be  exclusive of the others and all of
them are cumulative to the remedies for collection of indebtedness,  enforcement
or rights under the Security Documents, and preservation of security as provided
by law. No act of Lender shall be construed as an election to proceed  under any
one provision  herein to the exclusion of any other  provision or an election of
remedies to the bar of any other  remedy  allowed at law or in equity,  anything
herein or otherwise to the contrary notwithstanding.

     22.  Failure by Lender to exercise  any right  which it may have  hereunder
shall not be deemed a waiver  thereof unless so agreed in writing by Lender and,
if any such  waiver is given,  it shall not be deemed a  continuing  waiver or a
waiver of any other default or of the same default on another occasion.

     23. All notices  hereunder  shall be in writing and shall be deemed to have
been sufficiently given or served for all purposes when presented personally or,
if sent by mail, on the third  business day after being  deposited in the United
States  Mail,  postage  prepaid,  registered  or certified  with return  receipt
requested.  Any notices delivered  hereunder shall be addressed to the following
unless otherwise notified in accordance herewith:


<PAGE>



       Lender:                   Allianz Life Insurance Company of North America
                                 c/o Allianz of America, Inc.
                                 55 Greens Farms Road
                                 P. O. Box 5160
                                 Westport, Connecticut 06881-5160
                                 Attn: Real Estate Department

       Guarantor:                Mission West Properties, Inc.
                                 10050 Bandley Drive
                                 Cupertino, California 95014
                                 Attn:    Carl E. Berg
                                          Raymond V. Marino

     24.  Capitalized terms used but not otherwise defined herein shall have the
same meanings set forth in the Deed of Trust.

     IN WITNESS  WHEREOF,  this Limited Guaranty has been executed as of the day
and year first above written.

                                            MISSION WEST PROPERTIES, INC.,
                                            a Maryland corporation


                                            By: /s/ Carl E. Berg
                                               ---------------------------------
                                               Carl E. Berg,
                                               Chief Executive Officer