EXHIBIT 99.1 CALIFORNIA PIZZA KITCHEN, INC CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 In connection with the Quarterly Report of California Pizza Kitchen, Inc (the "Company") on Form 10-Q for the period ending June 29, 2003 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Richard L. Rosenfield, Co-Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C.1350, as adopted pursuant to 906 of the Sarbanes-Oxley Act of 2002, that: (1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and (2) The information contained in the Report fairly presents, in all material respects, the financial condition and result of operations of the Company. By: /s/ RICHARD L. ROSENFIELD ------------------------- Richard L. Rosenfield Co-Chief Executive Officer Exhibit 99.1 CALIFORNIA PIZZA KITCHEN, INC CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 In connection with the Quarterly Report of California Pizza Kitchen, Inc (the "Company") on Form 10-Q for the period ending June 29, 2003 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Larry S. Flax, Co-Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C.1350, as adopted pursuant to 906 of the Sarbanes-Oxley Act of 2002, that: (1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and (2) The information contained in the Report fairly presents, in all material respects, the financial condition and result of operations of the Company. By: /s/ LARRY S. FLAX ----------------- Larry S. Flax Co-Chief Executive Officer