Form 6-K

                             WASHINGTON, D. C. 20549

                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER

                      Pursuant to Rule 13a-16 or 15d-16 of

                       the Securities Exchange Act of 1934

                         For the month of May, 2005
                        Commission File Number: 001-06439

                                SONY CORPORATION
                 (Translation of registrant's name into English)


                    (Address of principal executive offices)

          The registrant files annual reports under cover of Form 20-F.

Indicate by check mark whether the registrant  files or will file annual reports
under cover of Form 20-F or Form 40-F,

                  Form 20-F  X                   Form 40-F __

Indicate by check mark whether the  registrant  by  furnishing  the  information
contained  in this  Form is  also  thereby  furnishing  the  information  to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934,
Yes No X

If "Yes" is marked, indicate below the file number assigned to the registrant in
connection with Rule 12g3-2(b):82-______


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, thereunto duly authorized.

                                                            SONY CORPORATION

                                         By:  /s/  Katsumi Ihara    

                                             Katsumi Ihara
                                             Executive Deputy President, 
                                             Group Chief Strategy Officer and
                                             Chief Financial Officer

Date: May 20, 2005

List of materials

Documents attached hereto:

i)  Press release announcing Tracking Stock (6758-5) Sony Communication
    Network Corporation announces notice regarding the sale of shares
    in So-net M3, Inc.

May 20, 2005

                                                  Company name: Sony Corporation
                         Representative's title and name: Chairman Nobuyuki Idei
                           (stock code: 6758 Tokyo Stock Exchange First Section)
                                                     (tracking stock subsidiary)
                            Company name: Sony Communication Network Corporation
             Representative's title and name: Representative Director, Corporate
                                  Executive Officer, President Kenichiro Yoshida
                         (stock code: 6758-5 Tokyo Stock Exchange First Section)
                    For inquiries: Corporate Executive Officer Masanao Yoshimura

                            TRACKING STOCK (6758-5)
                           ANNOUNCES NOTICE REGARDING
                     THE SALE OF SHARES IN So-net M3, Inc.

Sony Communication Network Corporation (hereinafter, "SCN"), a subsidiary whose
performance is linked to a tracking stock issued by Sony Corporation, announced
today the following decisions regarding a secondary offer of shares of So-net
M3, Inc.

SCN passed a resolution at its Board of Directors meeting today to conduct a
secondary offer of So-net M3 shares as follows:

-Outline of secondary offer

(1) Seller: Sony Communication Network Corporation
(2) Stock: Common stock of So-net M3 Inc.
(3) Number of shares to be sold: 17,935 shares of common stock
                                 (14.0% of issued shares.)
   (Notes) 1. The number of shares for secondary offer is subject to change
(4) Offering price: Undetermined
(5) Method of sale International offering

Cautionary Statement:

This communication is not an offer to sell or a solicitation of any offer to buy
the securities of So-net M3 (the "Company") in the United States. The securities
have not been and will not be registered under the United States Securities Act
of 1933 and may not be offered or sold in the United States absent registration
or an exemption from such registration requirement. If any public offering of
securities is made in the United States, it will be by means of a prospectus
that may be obtained from the Company or any selling security holder that will
contain detailed information about the Company and management, as well as
financial statements.