UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-K

                Current Report Pursuant to Section 13 or 15(d) of
                       The Securities Exchange Act of 1934

       Date of report (date of earliest event reported): December 18, 2006

                          MISSION WEST PROPERTIES, INC.
             (Exact name of registrant as specified in its charter)

           Maryland               Commission File Number:          95-2635431
      ------------------                  1-8383                   ----------
(State or other jurisdiction of                                 (I.R.S. Employer
         incorporation)                                          Identification)



                    10050 Bandley Drive, Cupertino, CA 95014
                    (Address of principal executive offices)

                                 (408) 725-0700
              (Registrant's telephone number, including area code)

Check  the  appropriate  box  below  if the  Form  8-K  filing  is  intended  to
simultaneously  satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):


[ ] Written communications pursuant to Rule 425 under the Securities Act
    (17 CFR 230.425)

[ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act
    (17 CFR 240.14a-12)

[ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange
    Act (17 CFR 240.14d-2(b))

[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange
    Act (17 CFR 240.13e-4(c))

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ITEM 3.01 NOTICE OF DELISTING OR FAILURE TO SATISFY A CONTINUED  LISTING RULE OR
          STANDARD; TRANSFER OF LISTING.

(d)  On December 18, 2006, Mission West Properties, Inc. announced its intention
     to voluntarily  withdraw its common stock from listing on NYSE Arca,  Inc.,
     formerly the Pacific Stock Exchange,  in order to reduce  duplicative costs
     and administrative  burdens inherent with maintaining dual listings on NYSE
     Arca and the American Stock Exchange. Mission West Properties will continue
     to maintain  the  principal  listing for its common  stock on the  American
     Stock  Exchange  and will  continue  to trade on NYSE  Arca on an  unlisted
     trading privilege basis.


ITEM 9.01 FINANCIAL STATEMENTS AND EXHIBITS.

     The following is filed as an exhibit to this report:

     99.1      Press Release, dated December 18, 2006, issued by Mission West
               Properties, Inc.



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                                    SIGNATURE

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned hereunto duly authorized.




                                        MISSION WEST PROPERTIES, INC.

Date: December 18, 2006                 By: /s/ Raymond V. Marino
                                           -----------------------------------
                                           Raymond V. Marino
                                           President and Chief Operating Officer

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Exhibit 99.1


                                                                   PRESS RELEASE


For Immediate News Release
December 18, 2006

   MISSION WEST PROPERTIES, INC. TO WITHDRAW PACIFIC EXCHANGE LISTING, RETAINS
                        AMERICAN STOCK EXCHANGE LISTING

  "We build the buildings for the high tech companies that build the internet"

CUPERTINO,  CA - MISSION WEST PROPERTIES,  INC. (AMEX/PCX:  MSW) today announced
plans to withdraw the listing of its common stock from NYSE Arca, Inc., formerly
the Pacific Exchange.  Mission West Properties' common stock will continue to be
listed on the American Stock Exchange.

Mission West Properties has decided to withdraw its listing from NYSE Arca, Inc.
to streamline operations and eliminate duplicative  administrative  requirements
inherent with dual listings.  The withdrawal is expected to be effective  within
the next month.

Mission West Properties does not believe that  withdrawing its listing from NYSE
Arca,  Inc. will have any impact on the  liquidity of its stock.  NYSE Arca will
continue to trade Mission West Properties stock on an unlisted trading privilege
basis.





Mission West Properties, Inc. operates as a self-managed,  self-administered and
fully integrated REIT engaged in the management, leasing, marketing, development
and acquisition of commercial R&D properties,  primarily  located in the Silicon
Valley portion of the San Francisco Bay Area. Currently, the Company manages 107
properties  totaling  approximately  7.7 million  square  feet.  For  additional
information, please contact Investor Relations at 408-725-0700.

The matters described herein contain forward-looking statements. Such statements
can be  identified  by the use of  forward-looking  terminology  such as "will",
"anticipate", "estimate", "expect", "intends", or similar words. Forward-looking
statements involve a number of risks,  uncertainties or other factors beyond the
Company's  control  which  may cause  material  differences  in actual  results,
performance or other  expectations.  These factors include,  but are not limited
to, the ability to complete  acquisitions under the Company's Berg Land Holdings
Option Agreement with the Berg Group, changing economic and real estate industry
conditions, leasing risk, rollover risk, tenant credit risk, interest rate risk,
and  other  factors  detailed  in the  Company's  registration  statements,  and
periodic filings with the Securities & Exchange Commission.


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