SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549



                                  SCHEDULE 13G
                               (Amendment No. 3)

                    Under the Securities Exchange Act of 1934

                          Mission West Properties, Inc.
                          -----------------------------
                                (Name of Issuer)

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

                                    605203108
                                    ---------
                                 (CUSIP Number)

                                December 31, 2003
                                -----------------
             (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).



CUSIP No. 605203108                                           Page 2 of 10 Pages
-------------------                                           ------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person
          Carl E. Berg
--------- ----------------------------------------------------------------------
     2)   Check the Appropriate Box if a Member of a Group (See Instructions)
           (a) [X] (b) [ ]
--------- ----------------------------------------------------------------------
     3)   SEC Use Only

--------- ----------------------------------------------------------------------
     4)   Citizenship or Place of Organization USA
--------- ----------------------------------------------------------------------
     Number of Shares       5) Sole Voting Power  0
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power  78,364,716
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  78,364,716
---------- ---------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          44,777,310
--------- ----------------------------------------------------------------------
    10)   Check if the Aggregate Amount in Row (9) Excludes Certain Shares [X]
          (See Instructions)
--------- ----------------------------------------------------------------------
    11)   Percent of Class Represented by Amount in Row (9)
          71.4 % *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------

     *    See Items 4. and 8., below


                                     - 2 -


CUSIP No. 605203108                                           Page 3 of 10 Pages
-------------------                                           ------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person
          Clyde J. Berg
--------- ----------------------------------------------------------------------
     2)   Check the Appropriate Box if a Member of a Group (See Instructions)
          (a) [X] (b) [ ]
--------- ----------------------------------------------------------------------
     3)   SEC Use Only

--------- ----------------------------------------------------------------------
     4)   Citizenship or Place of Organization USA
--------- ----------------------------------------------------------------------
     Number of Shares       5) Sole Voting Power  0
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power  78,364,716
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  78,364,716
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          44,376,789
--------- ----------------------------------------------------------------------
    10)   Check if the Aggregate Amount in Row (9) Excludes Certain Shares [X]
          (See Instructions)
--------- ----------------------------------------------------------------------
    11)   Percent of Class Represented by Amount in Row (9)
          71.3 % *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------

          *    See Items 4. and 8., below

                                     - 3 -

CUSIP No. 605203108                                           Page 4 of 10 Pages
-------------------                                           ------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person Berg & Berg Enterprises, Inc.
--------- ----------------------------------------------------------------------
     2)   Check the Appropriate Box if a Member of a Group (See Instructions)
          (a) [X] (b) [ ]
--------- ----------------------------------------------------------------------
     3)   SEC Use Only

--------- ----------------------------------------------------------------------
     4)   Citizenship or Place of Organization
          California
--------- ----------------------------------------------------------------------
     Number of Shares       5) Sole Voting Power  0
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power  78,364,716
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  78,364,716
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          10,789,383
--------- ----------------------------------------------------------------------
    10)   Check if the Aggregate Amount in Row (9) Excludes Certain Shares [X]
          (See Instructions)
--------- ----------------------------------------------------------------------
    11)   Percent of Class Represented by Amount in Row (9)
          37.6 % *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          CO
--------- ----------------------------------------------------------------------

          *    See Items 4. and 8., below

                                     - 4 -

CUSIP No. 605203108                                           Page 5 of 10 Pages
-------------------                                           ------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person
          1981 Kara Ann Berg Trust, Clyde J. Berg, Trustee
--------- ----------------------------------------------------------------------
     2)   Check the Appropriate Box if a Member of a Group (See Instructions)
          (a) [X] (b) [ ]
--------- ----------------------------------------------------------------------
     3)   SEC Use Only

--------- ----------------------------------------------------------------------
     4)   Citizenship or Place of Organization USA
--------- ----------------------------------------------------------------------
     Number of Shares       5) Sole Voting Power  0
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power  78,364,716
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  78,364,716
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          13,252,925
--------- ----------------------------------------------------------------------
    10)   Check if the Aggregate Amount in Row (9) Excludes Certain Shares [X]
          (See Instructions)
--------- ----------------------------------------------------------------------
    11)   Percent of Class Represented by Amount in Row (9)
          42.5 % *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------

          *    See Items 4. and 8., below

                                     - 5 -


CUSIP No. 605203108                                           Page 6 of 10 Pages
-------------------                                           ------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person
          Carl Berg's Child's Trust, Clyde J. Berg, Trustee
--------- ----------------------------------------------------------------------
     2)   Check the Appropriate Box if a Member of a Group (See Instructions)
          (a) [X] (b) [ ]
--------- ----------------------------------------------------------------------
     3)   SEC Use Only

--------- ----------------------------------------------------------------------
     4)   Citizenship or Place of Organization USA
--------- ----------------------------------------------------------------------
---------------------------
     Number of Shares       5) Sole Voting Power  0
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power  78,364,716
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  78,364,716
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person 898,319
--------- ----------------------------------------------------------------------
    10)   Check if the Aggregate Amount in Row (9) Excludes Certain Shares |X|
          (See Instructions)
--------- ----------------------------------------------------------------------
    11)   Percent of Class Represented by Amount in Row (9)
          4.8 % *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------

          *    See Items 4. and 8., below

                                     - 6 -


CUSIP No. 605203108                                           Page 7 of 10 Pages
-------------------                                           ------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person
          Berg & Berg Enterprises, LLC
--------- ----------------------------------------------------------------------
     2)   Check the Appropriate Box if a Member of a Group (See Instructions)
          (a) [X] (b) [ ]
--------- ----------------------------------------------------------------------
     3)   SEC Use Only

--------- ----------------------------------------------------------------------
     4)   Citizenship or Place of Organization USA
--------- ----------------------------------------------------------------------
     Number of Shares       5) Sole Voting Power  0
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power  78,364,716
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  78,364,716
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person 196,428
--------- ----------------------------------------------------------------------
    10)   Check if the Aggregate Amount in Row (9) Excludes Certain Shares [X]
          Not applicable.
          (See Instructions)
--------- ----------------------------------------------------------------------
    11)   Percent of Class Represented by Amount in Row (9) Less then 1 % *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          PN
--------- ----------------------------------------------------------------------

          *    See Items 4. and 8., below

                                     - 7 -


CUSIP No. 605203108                                           Page 8 of 10 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.   Each reporting person and the  citizenship or place or organization of
          the  reporting person are  identified on the  cover page or cover page
          addenda and are incorporated by reference in response to this item.

          The address of the principal business  office of each 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  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  17,894,691  shares of Common Stock  outstanding as of
          December 31, 2003.

          Regarding the beneficial ownership of each reporting person, reference
          is made to Item 4. of the  cover  page  addendum  for  each  reporting
          person and to Item 8., below.  The  beneficial  ownership of shares of
          Common  Stock by any  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 reporting  persons  constitute a group because under the Company's
          charter  and  certain  agreements  among the  Company,  the  reporting
          persons and other  parties,  the ownership  interests of the reporting
          persons  taking into account the shares of the Common Stock that would
          be issued upon the exchange of O.P.  Units for shares of Common Stock,
          are aggregated in determining whether the issuer is subject to certain
          restrictions  based  on  such  ownership,  including:

          -    the required  nomination of two  representatives of the reporting
               persons to the Company's board of directors

          -    whether   the   approval   of  the   reporting   person's   board
               representative  of certain  actions by the board of  directors is
               required

          -    the approval of a sale of substantially  all of the assets of the
               operating partnerships

                                     - 8 -


          In  addition,  the  Company'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 20% 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,  each of
          the reporting persons 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.

          Furthermore,  each reporting person disclaims  beneficial ownership of
          shares that could be acquired  upon the  exchange of O.P.  Units as to
          which such reporting person has no pecuniary interest.

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 and Item 8 below.

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.

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

          This  schedule is filed  pursuant to Rule  13d-1(d).  The responses to
          Items 2(a)-(c) identify each of the persons filing this statement. See
          Exhibit 99.

Item 9.   Notice of Dissolution of Group.

          Not applicable.

Item 10.  Certification.

          Not applicable.

                                     - 9 -


                                    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:  January 15, 2004



/s/ Carl E. Berg                           /s/ Clyde J. Berg
-----------------------------------        -----------------------------------
Carl E. Berg, as an individual,            Clyde J. Berg
an officer of Berg & Berg Enterprises,     Signing for himself as an individual,
Inc., and manager of Berg & Berg           as sole trustee of 1981 Kara Ann Berg
Enterprises, LLC                           Trust, and as sole trustee of the
                                           Carl Berg Child's Trust



                                     - 10 -



                                  EXHIBIT 99.1

                            SCHEDULE OF GROUP MEMBERS


                                                   Convertible O.P. Units and
       O.P. Unit Holder                                 Common Stock (1)
--------------------------------                --------------------------------
Carl E. Berg (2)                                              33,791,499
--------------------------------                --------------------------------
Clyde J. Berg (3)                                             19,436,162
--------------------------------                --------------------------------
Berg & Berg Enterprises, Inc (2) (3)                          10,789,383
--------------------------------                --------------------------------
Berg & Berg Enterprises, LLC (2)                                 196,428
--------------------------------                --------------------------------
Carl Berg Child's Trust (3)                                      898,319
--------------------------------                --------------------------------
1981 Kara Ann Berg Trust (3)                                  13,252,925
--------------------------------                --------------------------------

                  TOTAL                                       78,364,716




(1)  Includes O.P. Units and Common Stock held of record by the group member.

(2)  These group members may be considered under common control.

(3)  These group members may be considered under common control.





                                  EXHIBIT 99.2

                             JOINT FILING AGREEMENT


     Pursuant to Rule  13d-1(k)(1)  of the  Securities  and Exchange  Commission
under the  Securities  Exchange Act of 1934,  each of the parties  hereto agrees
that the  statement on Schedule 13G  (including  all  amendments  thereto)  with
respect to the beneficial  ownership of Common Stock of Mission West Properties,
Inc. to which this  agreement  is  attached  as an  exhibit,  is filed by and on
behalf of each such  person  and that any  amendments  thereto  will be filed on
behalf of each such person.

January 15, 2004



/s/ Carl E. Berg                           /s/ Clyde J. Berg
-----------------------------------        -----------------------------------
Carl E. Berg, as an individual,            Clyde J. Berg
an officer of Berg & Berg Enterprises,     Signing for himself as an individual,
Inc., and manager of Berg & Berg           as sole trustee of 1981 Kara Ann Berg
Enterprises, LLC                           Trust, and as sole trustee of the
                                           Carl Berg Child's Trust