SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549



                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934

                                (Amendment No. 3)

                         Mission West Properties, Inc.
                                (Name of Issuer)


                         Common Stock, $0.001 par value
                         (Title of Class of Securities)


                                    605203108
                                 (CUSIP Number)


                                December 31, 2008
             (Date of Event Which Requires Filing of this Statement)

     Check the  appropriate  box to  designate  the rule  pursuant to which this
Schedule is filed:

                  [ ] Rule 13d-1(b)

                  [ ] Rule 13d-1(c)

                  [X] Rule 13d-1(d)

     * The information required in the remainder of this cover page shall not be
deemed to be "filed"  for the purpose of Section 18 of the  Securities  Exchange
Act of 1934 ("Act") or otherwise  subject to the  liabilities of that section of
the Act, but shall be subject to all other  provisions of the Act (however,  see
the Notes).





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CUSIP No. 605203108                    13G                     Page 2 of 4 Pages
----------------------------                        ----------------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person
          Thelmer Aalgaard
--------- ----------------------------------------------------------------------
     2)   Check the Appropriate Box if a Member of a Group (See Instructions)
           (a) [ ]
           (b) [ ]
--------- ----------------------------------------------------------------------
     3)   SEC Use Only

--------- ----------------------------------------------------------------------
     4)   Citizenship or Place of Organization USA
--------- ----------------------------------------------------------------------
     Number of Shares       5) Sole Voting Power  1,849,505
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  1,849,505
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          1,849,505
--------- ----------------------------------------------------------------------
    10)   Check if the Aggregate Amount in Row (9) Excludes Certain Shares
          (See Instructions)
--------- ----------------------------------------------------------------------
    11)   Percent of Class Represented by Amount in Row (9)
          8.56 % *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------


*    See Item 4, below






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CUSIP No. 605203108                    13G                     Page 3 of 4 Pages
----------------------------                        ----------------------------

Item 1.   (a)  The name of the  issuer is Mission  West  Properties,  Inc.  (the
               "Company").

          (b)  The  principal  executive  offices of the  Company are located at
               10050 Bandley Drive, Cupertino, California 95014.

Item 2.   The  address of the principal business office  of the reporting person
          is 10050 Bandley Drive, Cupertino, California 95014.

          The title of class of  securities  and  CUSIP  number  for the  equity
          securities  covered by this report and citizenship are incorporated by
          reference from the cover page in response to this item.

Item 3.   If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or
          (c), check whether the person filing is a:

          This statement is being filed pursuant to 13d-1(d).

Item 4.   Ownership.

          The Company had  19,748,211  shares of Common Stock  outstanding as of
          December 31, 2008.

          Regarding the beneficial ownership of each reporting person, reference
          is made to Item 4. of the cover  page.  The  beneficial  ownership  of
          shares  of  Common  Stock  by the  reporting  person  is based on such
          reporting  person's  right to exchange O.P. Units for shares of Common
          Stock upon certain  conditions under an exchange rights agreement with
          the Company.

          The issuer's  charter and such  agreements  limit the number of shares
          that  can be held at any one  time  by the  reporting  persons  in the
          aggregate to the lesser of 9% of the outstanding  Common Stock and the
          maximum  percentage that individual  shareholders can own, directly or
          indirectly,  under  applicable REIT ownership  limits contained in the
          Internal  Revenue Code.  Consequently,  the reporting person disclaims
          beneficial  ownership  of all shares of Common  Stock in excess of the
          maximum number of shares that such reporting  person currently has the
          right to acquire, taking into account these ownership restrictions.

Item 5.   Ownership of Five Percent or Less of a Class.

          Not applicable.

Item 6.   Ownership of More than Five Percent on Behalf of Another Person.

          See responses in Item 4 above.

Item 7.   Identification and Classification of the Subsidiary Which Acquired the
          Security  Being Reported on by the  Parent Holding Company or  Control
          Person.

          Not applicable.

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CUSIP No. 605203108                    13G                     Page 4 of 4 Pages
----------------------------                        ----------------------------

Item 8.   Identification and Classification of Members of the Group.

          Not applicable.

Item 9.   Notice of Dissolution of Group.

          Not applicable.

Item 10.  Certification.

          Not applicable.

                                    SIGNATURE

     After  reasonable  inquiry and to the best of my  knowledge  and belief,  I
certify that the information  set forth in this statement is true,  complete and
correct.

Date:  February 4, 2009


                                       /s/ Thelmer Aalgaard
                                       -----------------------------------------
                                       Thelmer Aalgaard



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