FORM 8-K SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ---------------------- CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities and Exchange Act of 1934 ----------------------- Date of Report: April 21, 2004 PLEXUS CORP. ----------------------------------------------------- (Exact name of registrant as specified in its charter) Wisconsin 000-14824 39-1344447 ---------------------------- ----------- ------------------- (State or other jurisdiction (Commission (I.R.S. Employer of incorporation) File Number Identification No.) 55 Jewelers Park Drive, Neenah, Wisconsin 54957-0156 ----------------------------------------- ---------- (Address of principal executive offices) (Zip Code) Registrant's telephone number, including area code: (920) 722-3451 Item 12. Results of Operations and Financial Condition. On April 21, 2004, Plexus Corp. announced its results for the second quarter of fiscal 2004, ended March 31, 2004. A copy of Plexus' related press release is furnished to the Commission by attaching it as Exhibit 99.1 to this report. * * * * * SIGNATURES 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 hereunto duly authorized. Date: April 21, 2004 /s/ F. Gordon Bitter ------------------------------------ F. Gordon Bitter Chief Financial Officer 2 EXHIBIT INDEX Exhibit Number Description -------------- ----------- Exhibit 99.1 Press Release 3