SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) August 17, 1998 TELLABS, INC. (Exact name of registrant as specified in charter) Delaware 0-9692 36-3831568 (State or other jurisdiction (Commission (IRS employer of incorporation) file number) identification no.) 4951 Indiana Avenue, Lisle, Illinois 60532 (Address of principal executive office) (Zip Code) Registrant's telephone number, including area code (630) 378-8800 N/A (Former name or former address, if changed since last report) 1 ITEM 5. OTHER EVENTS On August 14, 1998, Tellabs, Inc. (the "Company") and CIENA Corporation ("CIENA") issued a joint press release announcing preliminary fiscal third quarter results for CIENA, reaffirmations of their recommendations in favor of the previously announced proposed merger from the Boards of Directors of the Company and CIENA, and a clarification of information previously reported in the proxy material. Further details are contained in a copy of the press release attached hereto as Exhibit 20.9, which is incorporated by reference herein. Also, the Company hereby provides an additional correction to its Proxy Statement dated July 21, 1998: On Page 10, "Selected Consolidated Financial Data of CIENA", gross profit for the six months ended April 30, 1998 and 1997 was $164,915 and $92,623, respectively. This information, previously reported in CIENA's Forms 10-Q for the respective periods, supersedes the gross profit amounts set forth in the Proxy Statement which were incorrect due to a clerical error. Item 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS (c) Exhibits Exhibit 20.9 - Joint press release issued by Tellabs, Inc. and CIENA Corporation on August 14, 1998. SIGNATURE 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. TELLABS, INC. August 17, 1998 s\ J. Peter Johnson --------------------- J. Peter Johnson Vice President, Controller and Chief Accounting Officer 2