(As filed July 16, 2004) File No. 70-9717 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Amendment No. 2 on FORM U-1/A APPLICATION OR DECLARATION UNDER THE PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 REGENCO LLC 6609-R West Washington Street West Allis, Wisconsin 53214 (Name of company filing this statement and address of principal executive offices) --------------------------------------------------- ALLIANT ENERGY CORPORATION (Name of top registered holding company parent) ---------------------------------------------------- F.J. Buri, Corporate Secretary Alliant Energy Corporation 4902 N. Biltmore Lane Madison, Wisconsin 53718 (Name and address of agent for service) ----------------------------------------------------- The Commission is requested to send copies of all notices, orders and communications in connection with this Application or Declaration to: Barbara J. Swan, General Counsel William T. Baker, Jr., Esq. Alliant Energy Corporation Thelen Reid & Priest LLP 4902 N. Biltmore Lane 875 Third Avenue Madison, Wisconsin 53718 New York, New York 10022 The Application-Declaration filed in this proceeding on July 12, 2000, as amended by Amendment No. 1, filed on August 28, 2000, is hereby withdrawn. SIGNATURE Pursuant to the requirements of the Public Utility Holding Company Act of 1935, as amended, the undersigned company has duly caused this statement filed herein to be signed on its behalf by the undersigned thereunto duly authorized. REGENCO LLC By:/s/ John C. Bobrowich ---------------------- Name: John C. Bobrowich Title: President and CEO Date: July 16, 2004 2