EX-99.906.CERT 5 a2129646zex-99_906cert.txt EX-99.906.CERT EXHIBIT-99.906.CERT CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 Frederick C. Castellani, President and Principal Executive Officer of MML Series Investment Fund (the "Registrant"), certifies to the best of his knowledge that: 1. The Registrant's periodic report on Form N-CSR for the period ended December 31, 2003 (the "Form N-CSR") fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and 2. The information contained in the Form N-CSR fairly presents, in all material respects, the financial condition and results of operations of the Registrant. /s/ Frederick C. Castellani ------------------------------------------------ Frederick C. Castellani President and Principal Executive Officer Date February 11, 2004 A signed original of this written statement required by Section 906 of the Sarbanes-Oxley Act of 2002, or other document authenticating, acknowledging, or otherwise adopting the signature that appears in typed form within the electronic version of this written statement required by Section 906 has been provided to the Registrant and will be retained by the Registrant and furnished to the Securities and Exchange Commission (the "Commission") or its staff upon request. This certification is being furnished to the Commission solely pursuant to 18 U.S.C. Section 1350 and is not being filed as part of the Form N-CSR with the Commission. CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 James S. Collins, Treasurer and Principal Financial Officer of MML Series Investment Fund (the "Registrant"), certifies to the best of his knowledge that: 1. The Registrant's periodic report on Form N-CSR for the period ended December 31, 2003 (the "Form N-CSR") fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and 2. The information contained in the Form N-CSR fairly presents, in all material respects, the financial condition and results of operations of the Registrant. /s/ James S. Collins ------------------------------------------------ James S. Collins Treasurer and Principal Financial Officer Date FEBRUARY 11, 2004 A signed original of this written statement required by Section 906 of the Sarbanes-Oxley Act of 2002, or other document authenticating, acknowledging, or otherwise adopting the signature that appears in typed form within the electronic version of this written statement required by Section 906 has been provided to the Registrant and will be retained by the Registrant and furnished to the Securities and Exchange Commission (the "Commission") or its staff upon request. This certification is being furnished to the Commission solely pursuant to 18 U.S.C. Section 1350 and is not being filed as part of the Form N-CSR with the Commission.