UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                   FORM U-9C-3

                      QUARTERLY REPORT PURSUANT TO RULE 58

                     FOR THE QUARTER ENDED DECEMBER 31, 2004

                               EXELON CORPORATION

                            10 South Dearborn Street
                                   37th Floor
                                 P.O. Box 805379
                             Chicago, IL 60680-5379














Inquiries concerning this Form U-9C-3
   should be directed to:                             Scott Peters
                                                      Exelon Corporation
                                                      10 South Dearborn Street
                                                      38th Floor
                                                      P.O. Box 805379
                                                      Chicago, IL 60680-5379



TABLE OF CONTENTS Item Page Number Number 1 Organization Chart 3 2 Issuances and Renewals of Securities and Capital Contributions Part I - Issuances and Renewals of Securities and Capital 3 Contributions Part II - Capital Contributions 3 3 Associate Transactions Part I - Transactions Performed by Reporting Companies on Behalf of Associate Companies 4 Part II - Transactions Performed by Associate Companies On Behalf of Reporting Companies 4 4 Summary of Aggregate Investment 5 5 Other Investments 6 6 Financial Statements and Exhibits 7 Signature 10 2

ITEM 1. ORGANIZATION CHART Not required for the fourth quarter of the calendar year. ITEM 2. Part I. ISSUANCES AND RENEWALS OF SECURITIES AND CAPITAL CONTRIBUTIONS (in thousands) - --------------- --------------- ---------------- ---------------- --------------- --------------- ------------ -------------- Company Person to Issuing Type of Principal Whom Security Collateral Consideration Securities Security Amount of Issue or Cost of Was Issued Given With Received For (Borrower) Issued Security Renewal Capital (Lender) Security Each Security - --------------- --------------- ---------------- ---------------- --------------- --------------- ------------ -------------- II Services, Revolving $ 73 Issue LIBOR plus 50 F&M Holdings None $ 73 Inc. credit basis points Company, LLC - --------------- --------------- ---------------- ---------------- --------------- --------------- ------------ -------------- Exelon Revolving $5,283 Issue LIBOR plus 50 Exelon None $5,283 Services, Inc credit basis points Enterprises Company, LLC - --------------- --------------- ---------------- ---------------- --------------- --------------- ------------ -------------- Fischbach & Revolving $1,100 Issue LIBOR plus 50 F&M Holdings None $1,100 Moore credit basis points Company, LLC Electric, Inc. - --------------- --------------- ---------------- ---------------- --------------- --------------- ------------ -------------- Part II. CAPITAL CONTRIBUTIONS (in thousands) - ------------------------------------------- ---------------------------------------- ---------------------------------------- Company Contributing Capital Company Receiving Capital Amount of Capital Contribution - ------------------------------------------- ---------------------------------------- ---------------------------------------- Exelon Generation Company, LLC Exelon Power Labs, LLC $679 - ------------------------------------------- ---------------------------------------- ---------------------------------------- Exelon Generation Company, LLC ExTex Marketing, LLC 23,217 - ------------------------------------------- ---------------------------------------- ---------------------------------------- ExTex Marketing, LLC ExTex Power, LP 23,419 - ------------------------------------------- ---------------------------------------- ---------------------------------------- Exelon Enterprises Company, LLC F&M Holdings Company, LLC 1,151 - ------------------------------------------- ---------------------------------------- ---------------------------------------- 3

ITEM 3. ASSOCIATE TRANSACTIONS Part I. Transactions Performed by Reporting Companies on Behalf of Associate Companies (in thousands) - ------------------------------------------------------------------------------------------------------------------------- Reporting Company Associate Company Types of Direct Indirect Costs Total Amount Services Costs Cost of Rendering Services Receiving Services Rendered Charged Charged Capital Billed - ------------------------------------------------------------------------------------------------------------------------- Exelon Power Labs, LLC Exelon Business Measuring & test 92 92 Services Company equipment, technical services - PECO - ------------------------------------------------------------------------------------------------------------------------- Exelon Power Labs, LLC Exelon Business Measuring & test 95 33 128 Services Company equipment, technical services - ComEd - ------------------------------------------------------------------------------------------------------------------------- Exelon Power Labs, LLC Exelon Generation Measuring & test 1,034 321 1,355 Company, LLC equipment, technical services - ------------------------------------------------------------------------------------------------------------------------- Exelon Power Labs, LLC AmerGen Measuring & test 342 88 430 equipment, technical services - ------------------------------------------------------------------------------------------------------------------------- Part II. Transactions Performed by Associate Companies on Behalf of Reporting Companies (in thousands) None. 4

ITEM 4. SUMMARY OF AGGREGATE INVESTMENT December 31, 2004 (in thousands) Investments in energy-related companies: Total consolidated capitalization of Exelon Corporation as of December 31, 2004 $23,103,000 Line 1 Total capitalization multiplied by 15% (line 1 multiplied by 0.15) 3,465,450 Line 2 Greater of $50 million or line 2 3,465,050 Line 3 Total current aggregate investment subsequent to October 20, 2000 (categorized by major line of energy-related business): Energy-related business category 2 $ 367,851 Energy-related business category 5 177,631 Energy-related business category 7 347,579 Energy-related business category 9 9,738 Energy-related business category 10 23,217 Total current aggregate investment 926,016 Line 4 ---------- Difference between the greater of $50 million or 15% of capitalization and the total aggregate investment of the registered holding company system (line 3 less line 4) $ 2,539,434 Line 5 ========== Investments in gas-related companies: NONE 5

ITEM 5. OTHER INVESTMENTS Filed under confidential treatment pursuant to Rule 104(b). 6

ITEM 6 - FINANCIAL STATEMENTS AND EXHIBITS A. Financial Statements - ------------------------ (1) Exhibit A-1 Statement of Income of Exelon Services, Inc. for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (2) Exhibit A-2 Balance Sheet of Exelon Services, Inc. at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (3) Exhibit A-3 Statement of Income of Exelon Thermal Holdings, Inc. for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (4) Exhibit A-4 Balance Sheet of Exelon Thermal Holdings, Inc. at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (5) Exhibit A-5 Statement of Income of Unicom Power Marketing, Inc. for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (6) Exhibit A-6 Balance Sheet of Unicom Power Marketing, Inc. at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (7) Exhibit A-7 Statement of Income of Adwin Equipment Company for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (8) Exhibit A-8 Balance Sheet of Adwin Equipment Company at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (9) Exhibit A-9 Statement of Income of F&M Holdings Company, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (10) Exhibit A-10 Balance Sheet of F&M Holdings Company, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (11) Exhibit B-1 Statement of Income of Penesco Company, LLC for three months and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (12) Exhibit B-2 Balance Sheet of Penesco Company, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (13) Exhibit B-3 Statement of Income of Cenesco Company, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (14) Exhibit B-4 Balance Sheet of Cenesco Company, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (15) Exhibit B-5 Statement of Income of Exelon Allowance Management Company, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). 7

(16) Exhibit B-6 Balance Sheet of Exelon Allowance Management Company, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (17) Exhibit B-7 Statement of Income of ExTex Marketing, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (18) Exhibit B-8 Balance Sheet of ExTex Marketing, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (19) Exhibit B-9 Statement of Income of Exelon New England Power Marketing LP for the three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (20) Exhibit B-10 Balance Sheet of Exelon New England Power Marketing LP at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (21) Exhibit B-11 Statement of Income of Exelon Hamilton, LLC for the three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (22) Exhibit B-12 Balance Sheet of Exelon Hamilton, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (23) Exhibit B-13 Statement of Income of Exelon Energy Company for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (24) Exhibit B-14 Balance Sheet of Exelon Energy Company at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (25) Exhibit B-15 Statement of Income of Exelon PowerLabs, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (26) Exhibit B-16 Balance Sheet of Exelon PowerLabs, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (27) Exhibit B-17 Statement of Income of ENEH Services, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (28) Exhibit B-18 Balance Sheet of ENEH Services, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (29) Exhibit B-19 Statement of Income of ExTex Retail Services Company, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (30) Exhibit B-20 Balance Sheet of ExTex Retail Services Company, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (31) Exhibit B-21 Statement of Income of North America Power Services, Inc. for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (32) Exhibit B-22 Balance Sheet of North America Power Services, Inc. at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). 8

(33) Exhibit B-23 Statement of Income of Sithe Overseas Power Services, Ltd. for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (34) Exhibit B-24 Balance Sheet of Sithe Overseas Power Services, Ltd. at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (35) Exhibit B-25 Statement of Income of Sithe Energy Management Services, Inc. for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (36) Exhibit B-26 Balance Sheet of Sithe Energy Management Services, Inc. at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (37) Exhibit B-27 Statement of Income of Sithe Energy Management Services II, Inc. for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (38) Exhibit B-28 Balance Sheet of Sithe Energy Management Services II, Inc. at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (39) Exhibit C-1 Statement of Income of Exelon Synfuel I, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (40) Exhibit C-2 Balance Sheet of Exelon Synfuel I, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (41) Exhibit C-3 Statement of Income of Exelon Synfuel II, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (42) Exhibit C-4 Balance Sheet of Exelon Synfuel II, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (43) Exhibit C-5 Statement of Income of Exelon Synfuel III, LLC for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (44) Exhibit C-6 Balance Sheet of Exelon Synfuel III, LLC at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (45) Exhibit C-7 Statement of Income of Horizon Energy Company for three and twelve months ended December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). (46) Exhibit C-8 Balance Sheet of Horizon Energy Company at December 31, 2004 - filed under confidential treatment pursuant to Rule 104(b). B. Exhibits -------- None. 9

SIGNATURE Pursuant to the requirements of the Public Utility Holding Company Act of 1935, Exelon Corporation has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. Date: March 29, 2005 Exelon Corporation Registrant By:/s/ Matthew F. Hilzinger --------------------------- Vice President and Corporate Controller With the above signature, I also hereby certify that the corresponding report on Form U-9C-3 for the twelve months ended December 31, 2004 has been filed with Exelon Corporation's interested state commissions whose names and addresses are listed below. Donna Caton, Chief Clerk Illinois Commerce Commission 527 East Capitol Avenue Springfield, Illinois 62706 James J. McNulty, Secretary Pennsylvania Public Utility Commission P.O. Box 3265 Harrisburg, Pennsylvania 17105-3265 10