SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549



                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934

                                (Amendment No. 5)


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


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


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


                                December 31, 2005
                        --------------------------------
             (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                   13G                     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  77,490,528
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  77,490,528
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          44,801,441
--------- ----------------------------------------------------------------------
    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)
          70.8% *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------


*    See Items 4. and 8., below

                                     - 2 -


------------------------                                 -----------------------
CUSIP No. 605203108                   13G                     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  77,490,528
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  77,490,528
--------- ----------------------------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          43,478,470
--------- ----------------------------------------------------------------------
    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)
          70.2% *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------

*    See Items 4. and 8., below

                                     - 3 -


------------------------                                 -----------------------
CUSIP No. 605203108                   13G                     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  77,490,528
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  77,490,528
--------- ----------------------------------------------------------------------
     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)
          36.9% *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          CO
--------- ----------------------------------------------------------------------

*    See Items 4. and 8., below

                                     - 4 -



------------------------                                 -----------------------
CUSIP No. 605203108                   13G                     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  77,490,528
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  77,490,528
--------- ----------------------------------------------------------------------
     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)
          41.8% *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          IN
--------- ----------------------------------------------------------------------

*    See Items 4. and 8., below

                                     - 5 -



------------------------                                 -----------------------
CUSIP No. 605203108                   13G                     Page 6 of 10 Pages
------------------------                                 -----------------------
--------- ----------------------------------------------------------------------
     1)   Name of Reporting Person
          West Coast Venture Capital, 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 USA
--------- ----------------------------------------------------------------------
     Number of Shares       5) Sole Voting Power  0
                            ----------------------------------------------------
    Beneficially Owned      6) Shared Voting Power  77,490,528
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  77,490,528
--------------------------- ----------------------------------------------------
     9)   Aggregate Amount Beneficially Owned by Each Reporting Person
          169,131
--------- ----------------------------------------------------------------------
    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)
          Less then 1% *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          CO
--------- ----------------------------------------------------------------------

*    See Items 4. and 8., below

                                     - 6 -


------------------------                                 -----------------------
CUSIP No. 605203108                   13G                     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  77,490,528
                            ----------------------------------------------------
    by Each Reporting       7) Sole Dispositive Power  0
                            ----------------------------------------------------
       Person with:         8) Shared Dispositive Power  77,490,528
--------- ----------------------------------------------------------------------
     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)
          1.1% *
--------- ----------------------------------------------------------------------
    12)   Type of Reporting Person (See Instructions)
          PN
--------- ----------------------------------------------------------------------

*    See Items 4. and 8., below

                                     - 7 -


------------------------                                 -----------------------
CUSIP No. 605203108                   13G                     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  18,448,791  shares of  Common  Stock outstanding as of
        December 31, 2005.

        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:  February 13, 2006



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

                                     - 10 -





                                  EXHIBIT 99.1

                            SCHEDULE OF GROUP MEMBERS



                                                 Convertible O.P. Units and
              O.P. Unit Holder                        Common Stock (1)
---------------------------------------------- --------------------------------

Carl E. Berg (2)                                              33,646,499
---------------------------------------------- --------------------------------
Clyde J. Berg (3)                                             19,436,162
---------------------------------------------- --------------------------------
Berg & Berg Enterprises, Inc (2) (3)                          10,789,383
---------------------------------------------- --------------------------------
Berg & Berg Enterprises, LLC (2)                                 196,428
---------------------------------------------- --------------------------------
West Coast Venture Capital, Inc. (2)                             169,131
---------------------------------------------- --------------------------------
1981 Kara Ann Berg Trust (3)                                  13,252,925
---------------------------------------------- --------------------------------

                  TOTAL                                       77,490,528
---------------------------------------------- --------------------------------




(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.

February 13, 2006


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