EXHIBIT 99.1

                            CERTIFICATION PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
                            (18 U.S.C. SECTION 1350)

            I, Robert Glaser, Chairman and Chief Executive Officer of
RealNetworks, Inc., certify, pursuant to 18 U.S.C. Section 1350, as adopted
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Annual
Report of RealNetworks, Inc. on Form 10-K for the fiscal year ended December 31,
2002 fully complies with the requirements of Section 13(a) or 15(d) of the
Securities Exchange Act of 1934 and that information contained in such Annual
Report on Form 10-K fairly presents in all material respects the financial
condition and results of operations of RealNetworks, Inc.

Date:  March 28, 2003


                                     By:  /s/ Robert Glaser
                                          -------------------------------------
                                          Name:  Robert Glaser
                                          Title: Chairman and Chief Executive
                                                 Officer