Date of Filing: October 20, 2000 File No.: 70-9645 - -------------------------------------------------------------------------------- Form U-5A NOTIFICATION OF REGISTRATION Filed under Section 5(a) of the Public Utility Holding Company Act of 1935 Exelon Corporation Name of Registrant The undersigned holding company hereby notifies the Securities and Exchange Commission that it registers under and pursuant to the provisions of Section 5(a) of the Public Utility Holding Company Act of 1935 and furnishes the following information as to the registrant and subsidiary companies thereof: (1) Exact name of registrant: Exelon Corporation (2) Address of principal executive offices: 10 South Dearborn Street, 37th Floor, Chicago, Illinois 60603 (3) Name and address of officer to whom notices and communications should be addressed: Ruth Ann M. Gillis Exelon Corporation 10 South Dearborn Street, 37th Floor, Chicago, Illinois 60603 (4) Certain information regarding the registrant and each subsidiary company thereof (indented to reflect parent-subsidiary relationships). The parent- subsidiary relationships set forth below does not assume the consummation of the realignment of certain of Exelon's non-utility subsidiary companies as contemplated by Exelon's Application-Declaration in File No. 1.070-09645 ("Merger U-1") and as authorized by the Commission in its order dated October 19, 2000 approving such Application-Declaration. EXELON CORPORATION & SUBSIDIARIES Name of Company Organization State Type of Business Commonwealth Edison Company Corporation IL Electric Utility Commonwealth Edison Company of Indiana, Inc. Corporation IN Energy-related ComEd Financing I Trust DE Financing ComEd Financing II Trust DE Financing ComEd Funding, LLC LLC DE Financing ComEd Transitional Funding Trust Trust DE Financing Commonwealth Research Corporation Corporation IL Energy/Utility related

Name of Company Organization State Type of Business Concomber Ltd Limited Bermuda Captive Insurance Company Edison Development Company Corporation DE Real Estate Edison Development Canada Inc. Corporation Canada Land Development Edison Finance Partnership Partnership Canada Financing Unicom Assurance Company Ltd. Company Bermuda Captive Insurance Company Unicom Enterprises, Inc. Corporation IL Energy Services Unicom Energy Services Inc. Corporation IL Energy-related Unicom Energy Inc. Corporation DE Energy-related Unicom Energy Ohio, Inc. Corporation DE Energy-related Unicom Mechanical Services, Inc. Corporation IL Energy Services Building Automated Systems and Services, Inc. Corporation MI Energy Services Bumler Heating and Specialties, Inc. Corporation MI Energy Services Metropolitan Mechanical Contractors, Inc. Corporation MN Energy Services Hoekstra Building Automation, Inc. Corporation IL Energy Services Access Systems, Inc. Corporation IL Energy Services Buckeye Acquisition Corporation Corporation DE Energy Services Reliance Mechanical Corp. Corporation OH Energy Services Unicom Power Holdings Inc. Corporation DE Energy-related Unicom Power Marketing Inc. Corporation DE Energy-related Unicom Healthcare Management Inc. Corporation IL Medical Plan Liabilities UT Holdings Inc. Corporation DE Energy systems Northwind Chicago LLC (50% interest) LLC DE Energy systems Unicom Thermal Development Inc. Corporation DE Energy systems Unicom Thermal Technologies Inc. Corporation IL Energy systems Unicom Thermal Technologies Boston Inc. Corporation DE Energy systems Northwind Boston LLC (25% interest) LLC MA Energy systems Unicom Thermal Technologies Houston Inc. Corporation DE Energy systems Northwind Houston LLC (25% interest) LLC DE Energy systems Northwind Houston LP (25% interest) Limited Partnership DE Energy systems Unicom Thermal Technologies North America Inc. Corporation DE Energy systems Northwind Thermal Technologies Canada Inc. Corporation Canada Energy systems Unicom Thermal Technologies Inc. Corporation Canada Energy systems UTT National Power Inc. Corporation IL Energy systems Northwind Midway LLC LLC DE Energy systems UTT Nevada Inc. Corporation NE Energy systems Northwind Aladdin LLC (75% interest) LLC NV Energy systems Northwind Las Vegas LLC (50% interest) LLC NV Energy systems UTT Phoenix, Inc. Corporation DE Energy systems Northwind Arizona Development LLC LLC DE Energy systems (50% interest) Northwind Phoenix LLC (50% interest) LLC DE Energy systems Unicom Investment Inc. Corporation IL Tax advantaged transactions Scherer Holdings 1, LLC LLC DE Tax advantaged transactions Scherer Holdings 2, LLC LLC DE Tax advantaged transactions Scherer Holdings 3, LLC LLC DE Tax advantaged transactions Spruce Holdings G.P. 2000, LLC LLC DE Tax advantaged transactions Spruce Holdings L.P. 2000, LLC LLC DE Tax advantaged transactions Spruce Equity Holdings, L.P. (1% interest held Limited Partnership DE Tax advantaged transactions by Spruce GP and 99% by Spruce LP) Spruce Holdings Trust (sole beneficiary is Statutory Business DE Tax advantaged transactions Spruce Equity Holdings L.P.) Trust Wansley Holdings 1, LLC Statutory Business DE Tax advantaged transactions Trust Wansley Holdings 2, LLC Statutory Business DE Tax advantaged transactions Trust Unicom Resources Inc. Corporation IL Inactive Boston Financial Institutional Tax Credit Fund X Corporation IL Tax advantaged transactions (approximately 11% interest) Boston Financial Institutional Tax Credit Fund XIX Limited Partnership MA Tax advantaged transactions (approximately 14% interest) Related Corporate Partners XII, L.P. (approximately Limited Partnership DE Tax advantaged transactions 36% interest) Boston Capital Corp. XIV (approximately 44% interest) Limited Partnership MA Tax advantaged transactions Boston Financial Institutional Tax Credit Fund XXI Limited Partnership MA Tax advantaged transactions (approximately 27% interest) Related Corporate Partners XIV, L.P. (approximately Limited Partnership DE Tax advantaged transactions 16%) Summit Corporate Tax Credit Fund II (approximately Limited Partnership WA Tax advantaged transactions 33% interest) USA Institutional Tax Credit Fund XXII Limited Partnership DE Tax advantaged transactions (approximately 30% interest) UTECH Climate Challenge Fund, L.P. (approximately 24% Limited Partnership DE Energy-related interest) Utility Competitive Advantage Fund I, LLC LLC DE Investment (holdings are Energy- (approximately 11.11% interest) related or Telecommunications)

Name of Company Organization State Type of Business Utility Competitive Advantage Fund II, LLC LLC DE Investment (holdings are Energy- (approximately 17.64% interest) related or Telecommunications) PECO Energy Company Corporation PA Electric and Gas Utility PECO Energy Capital Corp. Corporation DE Financing PECO Energy Capital, L.P. (3% interest) Limited Partnership DE Financing PECO Energy Capital Trust II Trust DE Financing PECO Energy Capital Trust III Trust DE Financing PECO Energy Transition Trust Statutory Business DE Financing Trust PECO Energy Power Company Corporation PA Utility Susquehanna Power Company Corporation MD Utility The Proprietors of the Susquehanna Canal Corporation MD Inactive Susquehanna Electric Company Corporation MD Utility AmerGen Energy Company, LLC (50% interest) LLC DE Exempt Wholesale Generator AmerGen Vermont, LLC LLC VT Exempt Wholesale Generator PECO Wireless, LLC LLC DE Telecommunications/Financing AT&T Wireless PCS of Philadelphia, LLC (49% LLC DE Telecommunications interest) ATNP Finance Company Corporation DE Financing PEC Financial Services, LLC LLC PA Financing PECO Hyperion Telecommunications (50% interest) General Partnership PA Telecommunications Eastern Pennsylvania Development Company Corporation PA Real Estate ("EPDC") Adwin Realty Company ("ARCO") Corporation PA Real Estate Ambassador II Joint Venture (50% interest) Partnership PA Real Estate Bradford Associates (50% interest) Partnership PA Real Estate Franklin Town Towers Associates Partnership PA Real Estate Henderson Ambassador Associates (50% Partnership PA Real Estate interest) Riverwatch Associates (1% interest held by Partnership PA Real Estate EPDC and 99% by ARCO) Route 724 (1% interest held by EPDC and Partnership PA Real Estate 99% by ARCO) Signa Joint Venture (1% interest held by Partnership PA Real Estate EPDC and 99% by ARCO) Energy Assets (10% interest) Corporation PA Energy-related Global EPS LLC (50% interest) LLC TX Inactive Exelon (Fossil) Holdings, Inc. Corporation DE Inactive Exelon Peaker Development General, LLC LLC DE Inactive Exelon Peaker Development Limited, LLC LLC DE Inactive Energy Trading Company Corporation DE Investment ExelonVentures Corp. Corporation PA Investment UniGrid Energy LLC (50% interest) LLC DE Energy-related CIC Global, LLC (50% interest) LLC DE Telecommunications Exelon Capital Partners, Inc. Corporation DE Investment (investments in Energy- related and Telecommunications) Extant, Inc. (approximately 12% interest) Corporation DE Permits Now (approximately 14.9% interest) Corporation MD VITTS Network Group, Inc. (approximately Corporation DE 16.8% interest) OmniChoice.com, Inc. (approximately Corporation DE 34.88% interest) Utility Competitive Advantage Fund I, LLC LLC DE Investment (holdings are Energy- (approximately 16.35% interest) related or Telecommunications) Exelon Infrastructure Services, Inc. Corporation DE Infrastructure Services (approximately 95% interest) Exelon Infrastructure Services of PA, Inc. Corporation DE Infrastructure Services Chowns Communications, Inc. Corporation DE Infrastructure Services Fischbach and Moore Electric, Inc. Corporation DE Infrastructure Services MRM Technical Group, Inc. Corporation DE Infrastructure Services Aconite Corporation Corporation MN Infrastructure Services Gas Distribution Contractors, Inc. Corporation MO Infrastructure Services Mid-Atlantic Pipeliners, Inc. Corporation DE Infrastructure Services

Name of Company Organization State Type of Business Mueller Distribution Contractors, Inc. Corporation GA Infrastructure Services Mueller Energy Services, Inc. Corporation NY Infrastructure Services Mueller Pipeliners, Inc. Corporation DE Infrastructure Services Mechanical Specialties Incorporated Corporation WI Infrastructure Services Rand-Bright Corporation Corporation WI Infrastructure Services Syracuse Merit Electric, Inc. Corporation DE Infrastructure Services NEWCOTRA, Inc. Corporation DE Infrastructure Services Fischbach and Moore, Incorporated Corporation NY Infrastructure Services Fischbach and Moore Electrical Corporation DE Infrastructure Services Contracting Inc. T.H. Green Electric Co., Inc. Corporation NY Infrastructure Services Trinity Industries, Inc. Corporation DE Infrastructure Services OSP Consultants, Inc. Corporation VA Infrastructure Services International Communications Services, Inc.Corporation NV Infrastructure Services OSP Inc. Corporation VA Infrastructure Services OSP Servicios, S.A. de C.V. S.A. de C.V. Mexico Inactive OSP Telecom, Inc. Corporation DE Infrastructure Services OSP Telecomm de Mexico, S.A. de C.V. S.A. de C.V. Mexico Inactive OSP Telcom de Colombia, LTDA LTDA Colombia Inactive OSP Telecommunications, Ltd. Limited Bermuda Inactive RJE Telecom, Inc. Corporation FL Infrastructure Services Utility Locate & Mapping Services, Inc. Corporation VA Infrastructure Services Dashiell Holdings Corp. Corporation DE Infrastructure Services Dashiell Corporation Corporation TX Infrastructure Services Dacon Corporation Corporation TX Infrastructure Services VSI Group Inc. Corporation DE Infrastructure Services International Vital Solutions Group, Inc. Corporation MD Infrastructure Services Michigan Trenching Service, Inc. Corporation MI Infrastructure Services Lyons Equipment, Inc. Corporation MI Infrastructure Services Adwin Equipment Company Corporation PA Energy-related Horizon Energy Company Corporation PA Inactive (Energy-related) East Coast Natural Gas Cooperative LLC LLC DE Energy Services (approximately 41.12% interest)

SIGNATURE Pursuant to the requirements of the Public Utility Holding Company Act of 1935, the registrant has caused this Notification of Registration to be duly signed on its behalf in the City of Chicago and State of Illinois on the 20th day of October, 2000. EXELON CORPORATION By: /s/ Ruth Ann M. Gillis ---------------------------- Name: Ruth Ann M. Gillis Title: Senior Vice President (Seal) Attest: /s/ Katherine K. Combs - ---------------------------- Katherine K. Combs Vice President and Corporate Secretary VERIFICATION State of Illinois County of Cook The undersigned being duly sworn deposes and says that she has duly executed the attached Notification of Registration dated October 20, 2000 for and on behalf of Exelon Corporation; that she is the Senior Vice President of such company; and that all action taken by stockholders, directors, and other bodies necessary to authorize deponent to execute and file such instrument has been taken. Deponent further says that she is familiar with such instrument and the contents thereof, and that the facts therein set forth are true to the best of her knowledge, information and belief. By: /s/ Ruth Ann M. Gillis -------------------------- Name: Ruth Ann M. Gillis (OFFICIAL SEAL) Subscribed and sworn to before me, a notary public this 20th day of October, 2000 /s/ Mary L. Kwilos - ---------------------- My commission expires October 26, 2001

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 In the Matter of ) Exelon Corporation ) ) File No. 70-9645 (Public Utility Holding ) Company Act of 1935) ) CERTIFICATE OF NOTIFICATION This Certificate of Notification is filed by Exelon Corporation ("Exelon"), a Pennsylvania Corporation, in connection with the following transactions proposed in Exelon's Form U-1, as amended (the "Application-Declaration"), and authorized by Order of the Securities and Exchange Commission (the "Commission") dated October 19, 2000 (the "Order"), in this file (Release No. 35-70-9645). Capitalized terms used herein without definition have the meaning ascribed to them in the Application-Declaration or the Amended and Restated Agreement and Plan of Exchange and Merger between Unicom Corporation ("Unicom") and PECO Energy Company ("PECO") (the "Merger Agreement"). Exelon Corporation hereby certifies pursuant to Rule 24: a. That Exelon has acquired common stock of (i) Commonwealth Edison Company ("ComEd"), a subsidiary of Unicom, (ii) PECO, and (iii) the utility subsidiaries of ComEd and PECO identified in the Application-Declaration. b. That Exelon has issued of its common stock in exchange for (i) the outstanding shares of common stock of PECO in the First Step Share Exchange and (ii) the outstanding shares of common stock of Unicom in the Second Step Merger. c. That Exelon adopted a service agreement to permit, under Section 13 of the Act and the rules of the Securities and Exchange Commission thereunder, Exelon Business Services Company to render services to Exelon's utility and non- utility subsidiaries. d. That PECO retains the gas utility business of PECO as an "additional system within the meaning of Section 11 of the Act. e. That Exelon retains directly or indirectly Unicom's and PECO's existing non-utility business. f. That except as noted the transactions described in the Application- Declaration have been completed. g. As set forth in the Application-Declaration the transactions (the "Restructurings") which will result in (i) the creation of Genco as the holder of the generating assets of ComEd and PECO, (ii) the creation of Exelon Energy Delivery Company as a holding company for ComEd and PECO and their subsidiaries, (iii) the creation of Exelon Ventures Company as a holding company for Genco, (iv) the Conowingo Companies becoming direct and indirect subsidiaries of Genco, and (v) the creation of Exelon Enterprises Company LLC which will hold Exelon's non-utility subsidiaries will be completed within one year. Because the transactions will be consummated by several steps, the "past tense" opinion will be filed at the completion of the last step (expected to be the Restructurings) as permitted by Instruction F(2) to Form U-1.

SIGNATURE Pursuant to the requirements of the Public Utility Holding Company Act of 1935, as amended, the undersigned company has duly caused this document to be signed on its behalf by the undersigned thereunto duly authorized. Exelon Corporation By:/s/ Ruth Ann M. Gillis ---------------------- Ruth Ann M. Gillis Senior Vice President Dated: October 20, 2000