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): May 27, 1999 Commission Registrant; State of Incorporation; IRS Employer File Number Address; and Telephone Number Identification No. - ----------- ---------------------------------- ------------------- 1-11375 UNICOM CORPORATION 36-3961038 (an Illinois corporation) 37th Floor, 10 South Dearborn Street Post Office Box A-3005 Chicago, Illinois 60690-3005 312/394-7399 1-1839 COMMONWEALTH EDISON COMPANY 36-0938600 (an Illinois corporation) 37th Floor, 10 South Dearborn Street Post Office Box 767 Chicago, Illinois 60690-0767 312/394-4321 Item 5. Other Events Commonwealth Edison Company ("ComEd"), a subsidiary of Unicom Corporation, issued a news release on May 27, 1999 (a copy of which is filed as an exhibit to this report and is hereby incorporated by reference) announcing that the Illinois legislature passed a bill which modifies certain provisions of the Illinois Electric Service Customer Choice and Rate Relief Law of 1997. The bill requires the signature of the Governor of Illinois to be enacted into law. Forward-Looking Statement: The statement in the attached press release regarding projected earnings per share is a forward- looking statement that involves risks and uncertainties. Actual results could differ materially as a result of such factors as (a) unforeseen developments in the market for electricity in Illinois resulting from regulatory changes, the influence of developments in the regulatory environments in other Midwestern states, adverse weather conditions and changes in the overall economy, any or all of which may affect ComEd's sales of electricity, and (b) the capacity factor of ComEd's nuclear generating stations, which may affect ComEd's electricity generation and purchased power costs. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrants have duly caused this report to be signed on their behalf by the undersigned thereunto duly authorized. UNICOM CORPORATION (Registrant) Date: May 27, 1999 By: John C. Bukovski ------------------------ John C. Bukovski Senior Vice President COMMONWEALTH EDISON COMPANY (Registrant) Date: May 27, 1999 By: John C. Bukovski ------------------------- John C. Bukovski Senior Vice President EXHIBIT INDEX Exhibit Number Description of Exhibit 1. None 2. None 4. None 16. None 17. None 20. None 23. None 24. None 27. None 99. News release dated May 27, 1999 issued by Commonwealth Edison Company