UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-Q/A

[X]         QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
            EXCHANGE ACT OF 1934

                  For the Quarterly Period Ended March 31, 2003
                                       OR

[ ]         TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
            EXCHANGE ACT OF 1934

Commission Name of Registrant; State of Incorporation; IRS Employer File Number Address of Principal Executive Offices; and Identification Telephone Number Number - --------------------- --------------------------------------------------------- ------------------------ 1-16169 EXELON CORPORATION 23-2990190 (a Pennsylvania corporation) 10 South Dearborn Street - 37th Floor P.O. Box 805379 Chicago, Illinois 60680-5379 (312) 394-7398 1-1839 COMMONWEALTH EDISON COMPANY 36-0938600 (an Illinois corporation) 10 South Dearborn Street - 37th Floor P.O. Box 805379 Chicago, Illinois 60680-5379 (312) 394-4321 1-1401 PECO ENERGY COMPANY 23-0970240 (a Pennsylvania corporation) P.O. Box 8699 2301 Market Street Philadelphia, Pennsylvania 19101-8699 (215) 841-4000 333-85496 EXELON GENERATION COMPANY, LLC 23-3064219 (a Pennsylvania limited liability company) 300 Exelon Way Kennett Square, Pennsylvania 19348 (610) 765-6900
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes [X] No [_]. The number of shares outstanding of each registrant's common stock as of March 31, 2003 was: Exelon Corporation Common Stock, without par value 324,234,521 Commonwealth Edison Company Common Stock, $12.50 par value 127,016,427 PECO Energy Company Common Stock, without par value 170,478,507 Exelon Generation Company, LLC not applicable Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Act). Exelon Corporation Yes [X] No [ ] Commonwealth Edison Company, PECO Energy Company and Exelon Generation Company, LLC Yes [ ] No [X]. TABLE OF CONTENTS Page No. FILING FORMAT 3 EXPLANATORY NOTE 3 PART I. FINANCIAL INFORMATION 4 ITEM 4. CONTROLS AND PROCEDURES 4 PART II. OTHER INFORMATION 7 ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K 7 SIGNATURES 10 2 FILING FORMAT This combined Form 10-Q/A is being filed separately by Exelon Corporation (Exelon), Commonwealth Edison Company (ComEd), PECO Energy Company (PECO) and Exelon Generation Company, LLC (Generation) (Registrants). Information contained herein relating to any individual registrant has been filed by such registrant on its own behalf. No registrant makes any representation as to information relating to any other registrant. EXPLANATORY NOTE Exelon, ComEd, PECO and Generation are filing this amendment on Form 10-Q/A in response to comments received from the staff of the Securities and Exchange Commission (SEC) in connection with its review of Exelon's Registration Statement on Form S-3 (File No. 333-108546), which incorporates this quarterly report by reference. This amendment makes changes to Part I, Item 4. Controls and Procedures to confirm that each Registrant's disclosure controls and procedures are effective and to clarify that each Registrant's access and ability to apply its disclosure controls and procedures to entities that it does not control or manage are more limited than subsidiaries that it controls and manages. Unless otherwise stated, all information contained in this amendment is as of May 2, 2003, the filing date of our original Quarterly Report on Form 10-Q for the quarter ended March 31, 2003. 3 PART I. FINANCIAL INFORMATION ITEM 4. CONTROLS AND PROCEDURES Exelon During the first quarter of 2003, Exelon's management, including the principal executive officer and principal financial officer, evaluated Exelon's disclosure controls and procedures related to the recording, processing, summarization and reporting of information in Exelon's periodic reports that it files with the SEC. These disclosure controls and procedures have been designed to ensure that (a) material information relating to Exelon, including its consolidated subsidiaries, is made known to Exelon's management, including these officers, by other employees of Exelon and its subsidiaries, and (b) this information is recorded, processed, summarized, evaluated and reported, as applicable, within the time periods specified in the SEC's rules and forms. Due to the inherent limitations of control systems, not all misstatements may be detected. These inherent limitations include the realities that judgments in decision-making can be faulty and that breakdowns can occur because of simple error or mistake. Additionally, controls could be circumvented by the individual acts of some persons or by collusion of two or more people. Exelon's controls and procedures can only provide reasonable, not absolute, assurance that the above objectives have been met. Exelon does not control or manage certain of its unconsolidated entities and thus its access and ability to apply its disclosure controls and procedures to entities that it does not control or manage are more limited than is the case for the subsidiaries it controls and manages. Accordingly, as of March 31, 2003, these officers (principal executive officer and principal financial officer) concluded that Exelon's disclosure controls and procedures were effective to accomplish their objectives. Exelon continually strives to improve its disclosure controls and procedures to enhance the quality of its financial reporting and to maintain dynamic systems that change as conditions warrant. ComEd During the first quarter of 2003, ComEd's management, including the principal executive officer and principal financial officer, evaluated ComEd's disclosure controls and procedures related to the recording, processing, summarization and reporting of information in ComEd's periodic reports that it files with the SEC. These disclosure controls and procedures have been designed to ensure that (a) material information relating to ComEd, including its consolidated subsidiaries, is made known to ComEd's management, including these officers, by other employees of ComEd and its subsidiaries, and (b) this information is recorded, processed, summarized, evaluated and reported, as applicable, within the time periods specified in the SEC's rules and forms. Due to the inherent limitations of control systems, not all misstatements may be detected. These inherent limitations include the realities that judgments in decision-making can be faulty and that breakdowns can occur because of simple error or mistake. Additionally, controls could be circumvented by the individual acts of some persons or by collusion of two or more people. ComEd's controls and procedures can only provide reasonable, not absolute, assurance that the above objectives have been met. ComEd does not control or manage certain of its unconsolidated entities and thus its access and 4 ability to apply its disclosure controls and procedures to entities that it does not control or manage are more limited than is the case for the subsidiaries it controls and manages. Accordingly, as of March 31, 2003, these officers (principal executive officer and principal financial officer) concluded that ComEd's disclosure controls and procedures were effective to accomplish their objectives. ComEd continually strives to improve its disclosure controls and procedures to enhance the quality of its financial reporting and to maintain dynamic systems that change as conditions warrant. PECO During the first quarter of 2003, PECO's management, including the principal executive officer and principal financial officer, evaluated PECO's disclosure controls and procedures related to the recording, processing, summarization and reporting of information in PECO's periodic reports that it files with the SEC. These disclosure controls and procedures have been designed to ensure that (a) material information relating to PECO, including its consolidated subsidiaries, is made known to PECO's management, including these officers, by other employees of PECO and its subsidiaries, and (b) this information is recorded, processed, summarized, evaluated and reported, as applicable, within the time periods specified in the SEC's rules and forms. Due to the inherent limitations of control systems, not all misstatements may be detected. These inherent limitations include the realities that judgments in decision-making can be faulty and that breakdowns can occur because of simple error or mistake. Additionally, controls could be circumvented by the individual acts of some persons or by collusion of two or more people. PECO's controls and procedures can only provide reasonable, not absolute, assurance that the above objectives have been met. PECO does not control or manage certain of its unconsolidated entities and thus its access and ability to apply its disclosure controls and procedures to entities that it does not control or manage are more limited than is the case for the subsidiaries it controls and manages. Accordingly, as of March 31, 2003, these officers (principal executive officer and principal financial officer) concluded that PECO's disclosure controls and procedures were effective to accomplish their objectives. PECO continually strives to improve its disclosure controls and procedures to enhance the quality of its financial reporting and to maintain dynamic systems that change as conditions warrant. Generation During the first quarter of 2003, Generation's management, including the principal executive officer and principal financial officer, evaluated Generation's disclosure controls and procedures related to the recording, processing, summarization and reporting of information in Generation's periodic reports that it files with the SEC. These disclosure controls and procedures have been designed to ensure that (a) material information relating to Generation, including its consolidated subsidiaries, is made known to Generation's management, including these officers, by other employees of Generation and its subsidiaries, and (b) this information is recorded, processed, summarized, evaluated and reported, as applicable, within the time periods specified in the SEC's rules and forms. Due to the inherent limitations of control systems, not all misstatements may be detected. These inherent limitations include the realities that judgments in decision-making can be faulty and that breakdowns can occur because of simple error or mistake. Additionally, 5 controls could be circumvented by the individual acts of some persons or by collusion of two or more people. Generation's controls and procedures can only provide reasonable, not absolute, assurance that the above objectives have been met. Generation does not control or manage certain of its unconsolidated entities and thus its access and ability to apply its disclosure controls and procedures to entities that it does not control or manage are more limited than is the case for the subsidiaries it controls and manages. Accordingly, as of March 31, 2003, these officers (principal executive officer and principal financial officer) concluded that Generation's disclosure controls and procedures were effective to accomplish their objectives. Generation continually strives to improve its disclosure controls and procedures to enhance the quality of its financial reporting and to maintain dynamic systems that change as conditions warrant. 6 PART II - OTHER INFORMATION ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K (a) Exhibits: 4-1 - One Hundredth Supplemental Indenture dated as of April 15, 2003 to PECO Energy Company's First and Refunding Mortgage.* Certifications Pursuant to Rule 13a-14(a) and 15d-14(a) of the Securities and Exchange Act of 1934 as to the Quarterly Report on Form 10-Q/A for the quarterly period ended March 31, 2003 filed by the following officers for the following companies: ------------------------------------------------------------------------- 31-1 - Filed by John W. Rowe for Exelon Corporation 31-2 - Filed by Robert S. Shapard for Exelon Corporation 31-3 - Filed by Michael B. Bemis for Commonwealth Edison Company 31-4 - Filed by J. Barry Mitchell for Commonwealth Edison Company 31-5 - Filed by Michael B. Bemis for PECO Energy Company 31-6 - Filed by J. Barry Mitchell for PECO Energy Company 31-7 - Filed by Oliver D. Kingsley Jr. for Exelon Generation Company, LLC 31-8 - Filed by J. Barry Mitchell for Exelon Generation Company, LLC ------------------------------------------------------------------------- Certifications Pursuant to Section 1350 of Chapter 63 of Title 18 United States Code (Sarbanes - Oxley Act of 2002) as to the Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2003 filed by the following officers for the following companies:* ------------------------------------------------------------------------- 99-1 - Filed by John W. Rowe for Exelon Corporation 99-2 - Filed by Robert S. Shapard for Exelon Corporation 99-3 - Filed by Pamela B. Strobel for Commonwealth Edison Company 99-4 - Filed by Robert S. Shapard for Commonwealth Edison Company 99-5 - Filed by Pamela B. Strobel for PECO Energy Company 99-6 - Filed by Robert S. Shapard for PECO Energy Company 99-7 - Filed by Oliver D. Kingsley Jr. for Exelon Generation Company, LLC 99-8 - Filed by Robert S. Shapard for Exelon Generation Company, LLC ------------------------------------------------------------------------- * Exhibits were filed with the Form 10-Q for the quarterly period ended March 31, 2003 filed on May 2, 2003 (File No. 1-16169, March 31, 2003 Form 10-Q, Exhibits 4-1 through 99-8). (b) Reports on Form 8-K: Exelon, ComEd, PECO and/or Generation filed Current Reports on Form 8-K during the three months ended March 31, 2003 regarding the following items:
Date of Earliest Event Reported Description of Item Reported - ------------------------------------------------------------------------------------------------------------ November 11, 2002 "ITEM 2. ACQUISITION OR DISPOSITION OF ASSETS" filed by Exelon and Generation regarding the acquisition of Sithe New England, "ITEM 5. OTHER EVENTS" filed by Exelon and Generation regarding the Sithe Boston credit facility and "ITEM 7. FINANCIAL STATEMENTS AND EXHIBITS" filed by Exelon and Generation for the financial statements of Sithe New England. 7 January 15, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed by Exelon, ComEd, PECO and Generation regarding the confirmation of earnings guidance for 2002 and 2003. January 22, 2003 "ITEM 5. OTHER EVENTS" filed by ComEd regarding the issuance of $700 million in First Mortgage Bonds. January 29, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed for Exelon, ComEd, PECO and Generation regarding the fourth quarter 2002 earnings release and items discussed during the Earnings Conference Call. February 11, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed for Exelon, ComEd, PECO and Generation regarding a presentation by John Rowe, Chairman and CEO and Bob Shapard, Executive Vice President and CFO at the Exelon Corporation Investor Update conference held in New York City. The exhibit includes the slides used during the presentation. February 21, 2003 "ITEM 5. OTHER EVENTS" filed for Exelon regarding certain financial information of Exelon Corporation and Subsidiary Companies. The exhibits under "ITEM 7. FINANCIAL STATEMENT AND EXHIBITS" filed for Exelon include the Consent of the Independent Public Accountants, Selected Financial Data, Market for Registrant's Common Equity and Related Stockholder Matters, Management's Discussion and Analysis of Financial Condition and Results of Operations, and Financial Statements and Supplementary Data. February 26, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed for Exelon, ComEd, PECO and Generation regarding a presentation by Bob Shapard, Executive Vice President and CFO and Linda Byus, Vice President Investor Relations to investors and information regarding the small and large commercial market share threshold auction in Pennsylvania. The exhibits include the slides used during the presentation and materials made available to investors attending the conference. March 3, 2003 "ITEM 5. OTHER EVENTS" filed for Exelon, ComEd, PECO and Generation regarding the reaffirmation of operating earnings guidance for 2003 and the discussion of ComEd's agreement regarding rate matters. 8 March 7, 2003 "ITEM 5. OTHER EVENTS" filed for Exelon and Generation regarding the announcement of the decision not to sell its interest in AmerGen. March 13, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed for Exelon, ComEd, PECO and Generation regarding a presentation by John Rowe, Chairman and CEO at the Morgan Stanley Global Electricity & Energy Conference held in New York City. The exhibit includes the slides used during the presentation. March 14, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed for Exelon, ComEd, PECO and Generation regarding comments and questions at the Morgan Stanley Global Electricity & Energy Conference. March 14, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed for Exelon, ComEd, PECO and Generation to amend the Current Report filed earlier in the same day, in order to clarify remarks made regarding British Energy and AmerGen at the Morgan Stanley Global Electricity & Energy Conference. March 17, 2003 "ITEM 5. OTHER EVENTS" filed by ComEd regarding the sale of $200 million in Trust Preferred Securities. March 26, 2003 "ITEM 9. REGULATION FD DISCLOSURE" filed for Exelon, ComEd, PECO and Generation regarding a presentation by J. Barry Mitchell, Senior Vice President and Treasurer at the Banc One Capital Markets Fixed Income Utilities Conference held in Chicago. The exhibit includes the slides used during the presentation. March 28, 2003 "ITEM 5. OTHER EVENTS" filed by Exelon and ComEd regarding the issuance of orders by the Illinois Commerce Commission resolving pending cases and addressing key issues in Illinois' continued transition to a competitive electricity marketplace. - ------------------------------------------------------------------------------------------------------------
9 SIGNATURES - -------------------------------------------------------------------------------- Pursuant to requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. EXELON CORPORATION
/s/ John W. Rowe /s/ Robert S. Shapard ---------------------------------------- -------------------------------------- JOHN W. ROWE ROBERT S. SHAPARD Chairman and Executive Vice President and Chief Chief Executive Officer Financial Officer (Principal Executive Officer) (Principal Financial Officer) /s/ Matthew F. Hilzinger ---------------------------------------- MATTHEW F. HILZINGER Vice President and Corporate Controller (Principal Accounting Officer) December 15, 2003 - -------------------------------------------------------------------------------- Pursuant to requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. COMMONWEALTH EDISON COMPANY /s/ Michael B. Bemis /s/ J. Barry Mitchell ---------------------------------------- ---------------------------------------- MICHAEL B. BEMIS J. BARRY MITCHELL President, Exelon Energy Delivery Chief Financial Officer (Principal Executive Officer) (Principal Financial Officer) /s/ Duane M. DesParte /s/ Frank M. Clark ---------------------------------------- ---------------------------------------- DUANE M. DESPARTE FRANK M. CLARK Vice President and Controller, President, ComEd Exelon Energy Delivery (Principal Accounting Officer) December 15, 2003 10 - -------------------------------------------------------------------------------- Pursuant to requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. PECO ENERGY COMPANY /s/ Michael B. Bemis /s/ J. Barry Mitchell ---------------------------------------- ------------------------------- MICHAEL B. BEMIS J. BARRY MITCHELL President, Exelon Energy Delivery Chief Financial Officer (Principal Executive Officer) (Principal Financial Officer) /s/ Duane M. DesParte /s/ Denis P. O'Brien ---------------------------------------- -------------------------------------- DUANE M. DESPARTE DENIS P. O'BRIEN Vice President and Controller, President, PECO Exelon Energy Delivery (Principal Accounting Officer) December 15, 2003 - -------------------------------------------------------------------------------- Pursuant to requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. EXELON GENERATION COMPANY, LLC /s/ Oliver D. Kingsley Jr. /s/ J. Barry Mitchell ---------------------------------------- ------------------------------- OLIVER D. KINGSLEY JR. J. BARRY MITCHELL Chief Executive Officer and Chief Financial Officer President (Principal Financial Officer) (Principal Executive Officer) /s/ Matthew F. Hilzinger ---------------------------------------- MATTHEW F. HILZINGER Vice President and Corporate Controller, Exelon (Principal Accounting Officer)
December 15, 2003 11
Exhibit 31-1

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, John W. Rowe, certify that:
1.   I have reviewed this quarterly report on Form 10-Q/A of Exelon Corporation;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:
          (a)  Designed such disclosure controls and procedures, or caused such
               disclosure controls and procedures to be designed under our
               supervision, to ensure that material information relating to the
               registrant, including its consolidated subsidiaries, is made
               known to us by others within those entities, particularly during
               the period in which this report is being prepared;
          (b)  Evaluated the effectiveness of the registrant's disclosure
               controls and procedures and presented in this report our
               conclusions about the effectiveness of the disclosure controls
               and procedures, as of the end of the period covered by this
               report based on such evaluation; and
          (c)  Disclosed in this report any change in the registrant's internal
               control over financial reporting that occurred during the
               registrant's most recent fiscal quarter that has materially
               affected, or is reasonably likely to materially affect, the
               registrant's internal control over financial reporting; and
5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):

          (a)  All significant deficiencies and material weaknesses in the
               design or operation of internal control over financial reporting
               which are reasonably likely to adversely affect the registrant's
               ability to record, process, summarize and report financial
               information; and

          (b)  Any fraud, whether or not material, that involves management or
               other employees who have a significant role in the registrant's
               internal control over financial reporting.

     Date:        December 15, 2003        /s/ John W. Rowe
                                           ------------------------------------
                                           Chairman and Chief Executive Officer
                                           (Principal Executive Officer)

Exhibit 31-2

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, Robert S. Shapard, certify that:
1.   I have reviewed this quarterly report on Form 10-Q/A of Exelon Corporation;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:
          (a)  Designed such disclosure controls and procedures, or caused such
               disclosure controls and procedures to be designed under our
               supervision, to ensure that material information relating to the
               registrant, including its consolidated subsidiaries, is made
               known to us by others within those entities, particularly during
               the period in which this report is being prepared;
          (b)  Evaluated the effectiveness of the registrant's disclosure
               controls and procedures and presented in this report our
               conclusions about the effectiveness of the disclosure controls
               and procedures, as of the end of the period covered by this
               report based on such evaluation; and
          (c)  Disclosed in this report any change in the registrant's internal
               control over financial reporting that occurred during the
               registrant's most recent fiscal quarter that has materially
               affected, or is reasonably likely to materially affect, the
               registrant's internal control over financial reporting; and
5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):
          (a)  All significant deficiencies and material weaknesses in the
               design or operation of internal control over financial reporting
               which are reasonably likely to adversely affect the registrant's
               ability to record, process, summarize and report financial
               information; and
          (b)  Any fraud, whether or not material, that involves management or
               other employees who have a significant role in the registrant's
               internal control over financial reporting.


     Date:  December 15, 2003        /s/ Robert S. Shapard
                                     ---------------------------------------
                                     Executive Vice President and
                                        Chief Financial Officer
                                     (Principal Financial Officer)


Exhibit 31-3

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, Michael B. Bemis, certify that:

1.   I have reviewed this quarterly report on Form 10-Q/A of Commonwealth Edison
     Company;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:

     (a)  Designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made known to
          us by others within those entities, particularly during the period in
          which this report is being prepared;

     (b)  Evaluated the effectiveness of the registrant's disclosure controls
          and procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of the period covered by this report based on such evaluation; and

     (c)  Disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most recent fiscal quarter that has materially affected, or is
          reasonably likely to materially affect, the registrant's internal
          control over financial reporting; and

5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):


     (a)  All significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect the registrant's ability to
          record, process, summarize and report financial information; and

     (b)  Any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          control over financial reporting.

     Date:   December 15, 2003      /s/ Michael B. Bemis
                                    -------------------------------------
                                    President, Exelon Energy Delivery
                                    (Principal Executive Officer)


Exhibit 31-4

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, J. Barry Mitchell, certify that:

1.   I have reviewed this quarterly report on Form 10-Q/A of Commonwealth Edison
     Company;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:
     (a)  Designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made known to
          us by others within those entities, particularly during the period in
          which this report is being prepared;
     (b)  Evaluated the effectiveness of the registrant's disclosure controls
          and procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of the period covered by this report based on such evaluation; and
     (c)  Disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most recent fiscal quarter that has materially affected, or is
          reasonably likely to materially affect, the registrant's internal
          control over financial reporting; and
5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):
     (a)  All significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect the registrant's ability to
          record, process, summarize and report financial information; and
     (b)  Any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          control over financial reporting.

     Date:  December 15, 2003        /s/ J. Barry Mitchell
                                     ----------------------------
                                     Chief Financial Officer
                                     (Principal Financial Officer)




Exhibit 31-5

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, Michael B. Bemis, certify that:
1.   I have reviewed this quarterly report on Form 10-Q/A of PECO Energy
     Company;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:
     (a)  Designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made known to
          us by others within those entities, particularly during the period in
          which this report is being prepared;
     (b)  Evaluated the effectiveness of the registrant's disclosure controls
          and procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of the period covered by this report based on such evaluation; and
     (c)  Disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most recent fiscal quarter that has materially affected, or is
          reasonably likely to materially affect, the registrant's internal
          control over financial reporting; and
5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):
     (a)  All significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect the registrant's ability to
          record, process, summarize and report financial information; and
     (b)  Any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          control over financial reporting.

     Date:  December 15, 2003         /s/ Michael B. Bemis
                                      ---------------------------------------
                                      President, Exelon Energy Delivery
                                      (Principal Executive Officer)

Exhibit 31-6

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, J. Barry Mitchell, certify that:

1.   I have reviewed this quarterly report on Form 10-Q/A of PECO Energy
     Company;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:
     (a)  Designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made known to
          us by others within those entities, particularly during the period in
          which this report is being prepared;
     (b)  Evaluated the effectiveness of the registrant's disclosure controls
          and procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of the period covered by this report based on such evaluation; and
     (c)  Disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most recent fiscal quarter that has materially affected, or is
          reasonably likely to materially affect, the registrant's internal
          control over financial reporting; and
5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):
     (a)  All significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect the registrant's ability to
          record, process, summarize and report financial information; and
     (b)  Any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          control over financial reporting.

     Date:   December 15, 2003        /s/ J. Barry Mitchell
                                      ----------------------------
                                      Chief Financial Officer
                                      (Principal Financial Officer)



Exhibit 31-7

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, Oliver D. Kingsley Jr., certify that:
1.   I have reviewed this quarterly report on Form 10-Q/A of Exelon Generation
     Company, LLC;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:
     (a)  Designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made known to
          us by others within those entities, particularly during the period in
          which this report is being prepared;
     (b)  Evaluated the effectiveness of the registrant's disclosure controls
          and procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of the period covered by this report based on such evaluation; and
     (c)  Disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most recent fiscal quarter that has materially affected, or is
          reasonably likely to materially affect, the registrant's internal
          control over financial reporting; and
5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):
     (a)  All significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect the registrant's ability to
          record, process, summarize and report financial information; and
     (b)  Any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          control over financial reporting.

     Date:  December 15, 2003          /s/ Oliver D. Kingsley Jr.
                                       ---------------------------------------
                                       Chief Executive Officer and President
                                       (Principal Executive Officer)


Exhibit 31-8

    CERTIFICATION PURSUANT TO RULE 13a-14(a) AND 15d-14(a) OF THE SECURITIES
                            AND EXCHANGE ACT OF 1934

I, J. Barry Mitchell, certify that:

1.   I have reviewed this quarterly report on Form 10-Q/A of Exelon Generation
     Company, LLC;
2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;
3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;
4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:
     (a)  Designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made known to
          us by others within those entities, particularly during the period in
          which this report is being prepared;
     (b)  Evaluated the effectiveness of the registrant's disclosure controls
          and procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of the period covered by this report based on such evaluation; and
     (c)  Disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most recent fiscal quarter that has materially affected, or is
          reasonably likely to materially affect, the registrant's internal
          control over financial reporting; and
5.   The registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors (or persons performing the equivalent functions):
     (a)  All significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect the registrant's ability to
          record, process, summarize and report financial information; and
     (b)  Any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          control over financial reporting.

     Date: December 15, 2003        /s/ J. Barry Mitchell
                                    ----------------------------
                                    Chief Financial Officer
                                    (Principal Financial Officer)