Registration No. 333-____


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



                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           THE SECURITIES ACT OF 1933



                               EXELON CORPORATION
             (Exact name of registrant as specified in its charter)

                 Pennsylvania                           23-2990190
        (State or other jurisdiction of       (I.R.S. Employer Identification
        incorporation or organization)                     No.)


                      37th Floor, 10 South Dearborn Street
                             Post Office Box 805379
                          Chicago, Illinois 60680-5379
                                 (312) 394-4321
                    (Address of principal executive offices)



                 EXELON CORPORATION EMPLOYEE STOCK PURCHASE PLAN
                            (Full title of the plan)


                               RUTH ANN M. GILLIS
                Senior Vice President and Chief Financial Officer
                               Exelon Corporation
                      37th Floor, 10 South Dearborn Street
                          Chicago, Illinois 60680-5379
                                 (312) 394-4321
                     (Name and address of agent for service)

                         CALCULATION OF REGISTRATION FEE


=====================================================================================================
                                                       Proposed
     Title of securities                               maximum        Proposed maximum      Amount of
       to be registered             Amount to be    offering price   aggregate offering   registration
                                     registered       per share             price              fee
- -----------------------------------------------------------------------------------------------------
                                                                             
Common Stock, no par value(1)      2,000,000       $68.385 (1)       $136,770,000 (1)     $34,192.50
                                   shares
=====================================================================================================

(1)      Estimated pursuant to Rule 457(h) and (c) solely for the purpose of
         calculating the registration fee, based upon the average of the high
         and low sales prices of shares of the common stock of Exelon
         Corporation as reported on the New York Stock Exchange on May 16, 2001.



PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT Item 3. Incorporation of Documents by Reference. The following documents, as filed by Exelon Corporation (the "Registrant") with the Securities and Exchange Commission (the "Commission"), are incorporated by reference in this Registration Statement and made a part hereof: (a) the Registrant's annual report on Form 10-K for the year ended December 31, 2000; (b) the Registrant's quarterly report on Form 10-Q for the quarter ended March 31, 2001; (c) the Registrant's Current Reports on Form 8-K dated January 12, 2001, January 30, 2001, February 26, 2001, March 16, 2001, April 4, 2001 and April 24, 2001; and (d) the description of the Registrant's common stock contained in the registration statement on Form 8-A filed under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), including any amendment thereto or report filed for the purpose of updating such description. All reports and other documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be part hereof from the date of filing of such documents. Any statement contained in any document, all or a portion of which is incorporated by reference herein, shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained or incorporated by reference herein modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement. Item 4. Description of Securities. Not applicable. Item 5. Interests of Named Experts and Counsel. Not applicable. 1

Item 6. Indemnification of Directors and Officers. Chapter 17, Subchapter D of the Pennsylvania Business Corporation Law of 1988, as amended (the "PBCL") contains provisions permitting indemnification of officers and directors of a business corporation incorporated in Pennsylvania. Sections 1741 and 1742 of the PBCL provide that a business corporation may indemnify directors and officers against liabilities and expenses he or she may incur in connection with a threatened, pending or completed civil, administrative or investigative proceeding by reason of the fact that he or she is or was a representative of the corporation or was serving at the request of the corporation as a representative of another enterprise, provided that the particular person acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, and, with respect to any criminal proceeding, had no reasonable cause to believe his or her conduct was unlawful. In general, the power to indemnify under these sections does not exist in the case of actions against a director or officer by or in the right of the corporation if the person otherwise entitled to indemnification shall have been adjudged to be liable to the corporation, unless it is judicially determined that, despite the adjudication of liability but in view of all the circumstances of the case, the person is fairly and reasonably entitled to indemnification for the expenses the court deems proper. Section 1743 of the PBCL provides that the corporation is required to indemnify directors and officers against expenses they may incur in defending these actions if they are successful on the merits or otherwise in the defense of such actions. Section 1746 of the PBCL provides that indemnification under the other sections of Subchapter D is not exclusive of other rights that a person seeking indemnification may have under any by-law, agreement, vote of shareholders or disinterested directors or otherwise, whether or not the corporation would have the power to indemnify the person under any other provision of law. However, Section 1746 prohibits indemnification in circumstances where the act or failure to act giving rise to the claim for indemnification is determined by a court to have constituted willful misconduct or recklessness. Section 1747 of the PBCL permits a corporation to purchase and maintain insurance on behalf of any person who is or was a director or officer of the corporation, or is or was serving at the request of the corporation as a representative of another enterprise, against any liability asserted against such person and incurred by him or her in that capacity, or arising out of his status as such, whether or not the corporation would have the power to indemnify the person against such liability under Subchapter D. The Registrant's by-laws provide that it is obligated to indemnify directors and officers and other persons designated by the board of directors against any liability, including any damage, judgment, amount paid in settlement, fine, penalty, cost or expense (including, without limitation, attorneys" fees and disbursements) incurred in connection with any proceeding. The Registrant's by-laws provide that no indemnification shall be made where the act or failure to act giving rise to the claim for indemnification is determined by arbitration or otherwise to have constituted willful misconduct or recklessness or attributable to receipt from the Registrant of a personal benefit to which the recipient is not legally entitled. 2

As permitted by PBCL Section 1713, the Registrant's by-laws provide that directors generally will not be liable for monetary damages in any action, whether brought by shareholders directly or in the right of the Registrant or by third parties, unless they fail in the good faith performance of their duties as fiduciaries (the standard of care established by the PBCL), and such failure constitutes self-dealing, willful misconduct or recklessness. The Registrant has purchased directors' and officers' liability insurance. Item 7. Exemption from Registration Claimed. Not applicable. Item 8. Exhibits. The following is a list of exhibits filed as part of this Registration Statement. Exhibit Number Description of Exhibit 4.1 Articles of Incorporation of Registrant (incorporated herein by reference to Exhibit 3.1 of the Registrant's Registration Statement on Form S-4, Registration Statement No. 333-37082). 4.2 Exelon Corporation Employee Stock Purchase Plan. 5.1 Opinion of Sidley Austin Brown & Wood. 23.1 Consent of PricewaterhouseCoopers LLP. 23.2 Consent of Sidley Austin Brown & Wood (included in its opinion filed as Exhibit 5.1 hereof). 24.1 Form of Powers of Attorney. Item 9. Undertakings. (a) The undersigned registrant hereby undertakes: (1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement: (i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933; (ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement; and 3

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement; Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed by the Registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement. (2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. (3) To remove from registration by means of a post-effective amendment any of the securities being registered that remain unsold at the termination of the offering. (b) The undersigned registrant hereby undertakes that, for the purpose of determining any liability under the Securities Act of 1933, each filing of the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered therein and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. (c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue. 4

SIGNATURES Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Philadelphia, Pennsylvania on the 22nd day of May, 2001. EXELON CORPORATION By: /s/ Corbin A. McNeill, Jr. ------------------------------- Corbin A. McNeill, Jr. Chairman and Co-Chief Executive Officer By: /s/ John W. Rowe ------------------------------- John W. Rowe President and Co-Chief Executive Officer Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons in the capacities and on May 22, 2001. Signature Capacity Date /s/ Corbin A. McNeill, Jr. Chairman, Co-Chief Executive Officer May 22, 2001 - --------------------------- and Director Corbin A. McNeill, Jr. /s/ John W. Rowe President, Co-Chief Executive May 22, 2001 - --------------------------- Officer and Director John W. Rowe /s/ Ruth Ann M. Gillis Senior Vice President and Chief May 22, 2001 - --------------------------- Financial Officer Ruth Ann M. Gillis (Principal Financial Officer) /s/ Jean Gibson Vice President and Corporate May 22, 2001 - --------------------------- Controller Jean Gibson (Principal Accounting Officer) This Registration Statement has also been signed by John W. Rowe in his individual capacity as a Director and as Attorney-in-Fact, on behalf of the following Directors on the date indicated: Edward A. Brennan Carlos H. Cantu Admiral Daniel L. Cooper M. Walter D'Alessio Admiral Bruce DeMars G. Fred DiBona, Jr. Sue Ling Gin Richard H. Glanton Rosemarie B. Greco Edgar D. Jannotta Corbin A. McNeill, Jr. John W. Rogers John M. Palms Ronald Rubin Richard L. Thomas By: /s/ John W. Rowe --------------------------- John W. Rowe (Director and Attorney-in-Fact for the Directors set forth above) 5

Exhibit Index Exhibit Number Description of Exhibit 4.1 Articles of Incorporation of Registrant (incorporated herein by reference to Exhibit 3.1 of the Registrant's Registration Statement on Form S-4, Registration Statement No. 333-37082). 4.2 Exelon Corporation Employee Stock Purchase Plan. 5.1 Opinion of Sidley Austin Brown & Wood. 23.1 Consent of PricewaterhouseCoopers LLP. 23.2 Consent of Sidley Austin Brown & Wood (included in its opinion filed as Exhibit 5.1 hereof). 24.1 Form of Powers of Attorney. 6

                                                                     EXHIBIT 4.2


                               EXELON CORPORATION

                          EMPLOYEE STOCK PURCHASE PLAN


                  1. Purpose. The purpose of the Exelon Corporation Employee
Stock Purchase Plan (the "Plan") is to provide employees of Exelon Corporation,
a Pennsylvania corporation (the "Company"), and its Subsidiary Companies (as
defined below) added incentive to remain employed by such companies and to
encourage increased efforts to promote the best interests of such companies by
permitting eligible employees to purchase shares of common stock, no par value,
of the Company ("Common Stock") at below-market prices. The Plan is intended to
qualify as an "employee stock purchase plan" under section 423 of the Internal
Revenue Code of 1986, as amended (the "Code"). For purposes of the Plan, the
term "Subsidiary Companies" shall mean all corporations which are subsidiary
corporations (within the meaning of Section 424(f) of the Code) and of which the
Company is the common parent. The Company and its Subsidiary Companies that,
from time to time, have been designated by the Plan Administrator as eligible to
participate in the Plan with respect to their employees are hereinafter referred
to collectively as the "Participating Companies."

                  2. Eligibility. (a) Eligible Employee. Participation in the
Plan shall be limited to each employee of the Participating Companies who
satisfies all of the following conditions (an "Eligible Employee") as of the
first day of the relevant Purchase Period (as defined in Section 3):

                  (i) such employee's customary employment is for 20 or more
                      hours per week; and

                  (ii) such employee has been continuously employed by the
                      Participating Companies for at least 3 consecutive
                      calendar months.

                  Notwithstanding the foregoing, an individual rendering
services to a Participating Company pursuant to either of the following
agreements shall not be considered an Eligible Employee with respect to any
period preceding the date on which a court or administrative agency issues a
final determination that such individual is an employee: (1) an agreement
providing that such services are to be rendered as an independent contractor or
(2) an agreement with an entity, including a leasing organization within the
meaning of section 414(n)(2) of the Code, that is not a Participating Company.

                  (b) Limitations. Notwithstanding anything contained in the
Plan to the contrary, no Eligible Employee shall acquire a right to purchase
Common Stock hereunder to the extent that (i) immediately after receiving such
right, such employee would own 5% or more of the total combined voting power or
value of all classes of stock of the Company or any Subsidiary Company
(including any stock attributable to such employee under section 424(d) of the
Code), or (ii) for any calendar year such right would permit such employee's
aggregate rights to purchase stock under all employee stock purchase plans of
the Company and its Subsidiary Companies exercisable during such calendar year


                                      A-1

to accrue at a rate which exceeds $25,000 of fair market value of such stock for such calendar year. In addition, the number of shares of Common Stock which may be purchased by any Eligible Employee during any Purchase Period shall not exceed 125 (subject to adjustment pursuant to Section 12), or such other number as may be determined by the Plan Administrator (as defined in Section 11) and set forth in a written Appendix to the Plan. 3. Effective Date; Purchase Periods. (a) Effective Date. The Plan shall become effective on June 1, 2001 or on such later date as may be specified by the Board of Directors (the "Board") of the Company or the Plan Administrator (as defined in Section 11). The Plan shall cease to be effective unless, within 12 months after the date of its adoption by the Board, it has been approved by the shareholders of the Company. (b) Purchase Periods. A "Purchase Period" shall consist of the three consecutive month period beginning on each July 1, October 1, January 1 and April 1 commencing on or after the effective date of the Plan and prior to its termination. 4. Participation. (a) Enrollment. Each Eligible Employee shall be entitled to enroll in the Plan as of any Purchase Period which begins on or after such employee has become an Eligible Employee. To enroll in the Plan, an Eligible Employee shall make a request to the Company or its designated agent at the time and in the manner specified by the Plan Administrator (as defined in Section 11), specifying the amount of payroll deduction to be applied to the compensation paid to the employee by the employee's employer while the employee is a participant in the Plan. The amount of each payroll deduction specified in such request for each such payroll period shall be a whole percentage amount, unless otherwise determined by the Plan Administrator, not to exceed 10%, or such lesser percentage as may be determined by the Plan Administrator, of the participant's regular base salary or wages (before withholding or other deductions) paid to him or her during the Purchase Period by any of the Participating Companies. Subject to compliance with applicable rules prescribed by the Plan Administrator, the request shall become effective as of the Purchase Period following the day the Company or its designated agent receives such request. Payroll deductions shall be made for each participant in accordance with such participant's request until such participant's participation in the Plan terminates, such participant's request is revised or the Plan is suspended or terminated, all as hereinafter provided. (b) Changes to Rate of Payroll Deduction. A participant may change the amount of his or her payroll deduction under the Plan effective as of any subsequent Purchase Period by so directing the Company or its designated agent at the time and in the manner specified by the Plan Administrator. A participant may not change the amount of his or her payroll deduction effective as of any time other than the beginning of a Purchase Period, except that a participant may elect to suspend his or her payroll deduction under the Plan as provided in Section 7. A-2

(c) Purchase Accounts. Payroll deductions for each participant shall be credited to a purchase account established on behalf of the participant on the books of the participant's employer or such employer's designated agent (a "Purchase Account"). At the end of each Purchase Period, the amount in each participant's Purchase Account will be applied to the purchase of the number of whole and fractional shares of Common Stock determined by dividing such amount by the Purchase Price (as defined in Section 5) for such Purchase Period. No interest shall accrue at any time for any amount credited to a Purchase Account of a participant (except as required by local law as determined by the Plan Administrator). 5. Purchase Price. The purchase price (the "Purchase Price") per share of Common Stock hereunder for any Purchase Period shall be 90% of the lesser of (i) the closing price of a share of Common Stock on the New York Stock Exchange on the first day of such Purchase Period on which such exchange is open for trading or (ii) the closing price of a share of Common Stock on such exchange on the last day of such Purchase Period on which such exchange is open for trading. If such sum results in a fraction of one cent, the Purchase Price shall be increased to the next higher full cent. 6. Issuance of Stock. The Common Stock purchased by each participant shall be issued in book entry form and shall be considered to be issued and outstanding to such participant's credit as of the end of the last day of each Purchase Period. A participant will be issued a certificate for his or her whole number of shares of Common Stock which have been held in book entry form for at least two years following the first day of the Purchase Period in which such shares were purchased, upon request of such participant or his or her legal representative or, if so directed by the Plan Administrator (as defined in Section 11), upon the termination of the Plan. In such event, the cash equivalent of any fractional shares shall also be distributed to such participant. Such cash equivalent shall be determined by multiplying the fractional share by the fair market value of a share of Common Stock (determined as provided in Section 5) on the last day of the Purchase Period immediately preceding such issuance. The Plan Administrator may permit or require that shares be deposited directly with a broker designated by the Plan Administrator or to a designated agent of the Company, and the Plan Administrator may use electronic or automated methods of share transfer. The Plan Administrator may require that shares be retained with such broker or agent for a designated period of time and/or may establish other procedures to permit tracking of disqualifying dispositions of such shares, and may also impose a transaction fee with respect to a sale of shares of Common Stock issued to a participant's credit and held by such a broker or agent. The Plan Administrator may permit shares purchased under the Plan to participate in a dividend reinvestment plan or program maintained by the Company, and establish a default method for the payment of dividends. After the close of each Purchase Period, information will be made available to each participant regarding the entries made to such participant's Purchase Account, the number of shares of Common Stock purchased and the applicable Purchase Price. In the event that the maximum number of shares of Common Stock are purchased by the participant for the Purchase Period and cash remains credited to the participant's Purchase Account, such cash shall be refunded to such participant. For purposes of the preceding sentence, the A-3

maximum number of shares of Common Stock that may be purchased by a participant for a Purchase Period shall be determined under Section 2. 7. Suspension of Payroll Deduction or Termination of Participation. (a) Suspension of Payroll Deduction. A participant may elect at any time and in the manner specified by the Plan Administrator (as defined in Section 11) to suspend his or her payroll deduction under the Plan, provided such election is received by the Company or its designated agent prior to the date specified by the Plan Administrator for suspension of payroll deduction with respect to a Purchase Period. If the election is not received by such date, such suspension of payroll deduction shall be effective as of the next succeeding Purchase Period. Upon a participant's suspension of payroll deduction, any cash credited to such participant's Purchase Account shall be refunded to such participant. A participant who suspends payroll deduction under the Plan shall be permitted to resume payroll deduction as of any Purchase Period following the Purchase Period in which such suspension was effective, by making a new request at the time and in the manner specified by the Plan Administrator. (b) Termination of Participation. If the participant dies, terminates employment with the Participating Companies for any reason, or otherwise ceases to be an Eligible Employee, such participant's participation in the Plan shall immediately terminate. Upon such terminating event, the cash credited to such participant's Purchase Account on the date of such termination shall be refunded to such participant or his or her legal representative, as the case may be. 8. Termination, Suspension or Amendment of the Plan. (a) Termination. The Company, by action of the Board or the Plan Administrator (as defined in Section 11), may terminate the Plan at any time, in which case notice of such termination shall be given to all participants, but any failure to give such notice shall not impair the effectiveness of the termination. Without any action being required, the Plan shall terminate in any event when the maximum number of shares of Common Stock to be sold under the Plan (as provided in Section 12) has been purchased. Such termination shall not impair any rights which under the Plan shall have vested on or prior to the date of such termination. If at any time the number of shares of Common Stock remaining available for purchase under the Plan are not sufficient to satisfy all then-outstanding purchase rights, the Board or Plan Administrator may determine an equitable basis of apportioning available shares of Common Stock among all participants. At any time following the termination of the Plan, the Plan Administrator may direct that one or more certificates for the number of whole shares of Common Stock held for each participant's benefit and the cash equivalent of any fractional share so held shall be delivered to such participant. Such cash equivalent shall be determined by multiplying the fractional share by the fair market value of a share of Common Stock (determined as provided in Section 5) on the last day of the Purchase Period immediately preceding such termination. Except as otherwise provided in Section 14, the A-4

cash, if any, credited to each participant's Purchase Account shall be distributed to such participant as soon as practicable after the Plan terminates. (b) Suspension or Amendment. The Board or the Plan Administrator may suspend payroll deductions under the Plan or amend the Plan from time to time in any respect for any reason; provided, however, that no such suspension or amendment shall (a) materially adversely affect any purchase rights outstanding under the Plan during the Purchase Period in which such amendment or suspension is adopted, (b) increase the maximum number of shares of Common Stock which may be purchased under the Plan, (c) decrease the Purchase Price of a share of Common Stock for any Purchase Period below the lesser of 85% of the fair market value thereof on the first day of such Purchase Period and 85% of such fair market value on the last day of such Purchase Period or (d) adversely affect the qualification of the Plan under section 423 of the Code. If payroll deductions under the Plan are suspended pursuant to this Section, such payroll deductions shall resume as of the first Purchase Period commencing with or immediately following the date on which such suspension ends, in accordance with the participants' payroll deduction elections then in effect. 9. Non-Transferability. Rights acquired under the Plan are not transferable and may be exercised only by a participant or his or her legal representative, as the case may be. 10. Shareholder's Rights. No Eligible Employee or participant shall by reason of the Plan have any rights of a shareholder of the Company until he or she shall acquire a share of Common Stock as herein provided. 11. Administration of the Plan. The Plan shall be administered by the Treasurer of the Company (the "Plan Administrator"). In addition to the powers and authority specifically granted to the Plan Administrator pursuant to any other provision of the Plan, the Plan Administrator shall have full power and authority to: (i) interpret and administer the Plan and any instrument or agreement entered into under the Plan; (ii) establish such rules and regulations and appoint such agents as it shall deem appropriate for the proper administration of the Plan; (iii) designate which Subsidiary Companies shall participate in the Plan; (iv) make any other determination and take any other action that the Plan Administrator deems necessary or desirable for administration of the Plan. Decisions of the Plan Administrator shall be final, conclusive and binding upon all persons having an interest in the Plan. The Plan shall be administered so as to ensure that all participants have the same rights and privileges as are provided by section 423(b)(5) of the Code. 12. Maximum Number of Shares. The maximum number of shares of Common Stock which may be purchased under the Plan is 5,000,000, subject to adjustment as set forth below. Shares of Common Stock sold hereunder may be treasury shares, authorized and unissued shares, shares purchased for participants in the open market (on an exchange or in negotiated transactions) or any combination thereof. If the Company shall, at any time after the effective date of the Plan, change its issued Common Stock into an increased number of shares, with or without par value, through a stock dividend or a stock split, or into a decreased number of shares, with or without par value, through a combination of shares, then, effective with the record date for such change, A-5

the maximum number of shares of Common Stock which thereafter may be purchased under the Plan and the maximum number of shares which thereafter may be purchased during any Purchase Period shall be the maximum number of shares which, immediately prior to such record date, remained available for purchase under the Plan and under any Purchase Period proportionately increased, in case of such stock dividend or stock split, or proportionately decreased in case of such combination of shares. 13. Miscellaneous. Except as otherwise expressly provided herein, (i) any request, election or notice under the Plan from an Eligible Employee or participant shall be transmitted or delivered to the Company or its designated agent and, subject to any limitations specified in the Plan, shall be effective when so delivered and (ii) any request, notice or other communication from the Company or its designated agent that is transmitted or delivered to Eligible Employees or participants shall be effective when so transmitted or delivered. The Plan, and the Company's obligation to sell and deliver shares of Common Stock hereunder, shall be subject to all applicable federal and state laws, rules and regulations, and to such approval by any regulatory or governmental agency as may, in the opinion of counsel for the Company, be required. 14. Change in Control. In the event of any Change in Control of the Company, as defined below, the then current Purchase Period shall thereupon end, the Plan Administrator shall direct that the cash credited to all participants' Purchase Accounts shall be applied to purchase shares pursuant to Sections 4, 5 and 6 or refunded to participants, and the Plan shall immediately terminate. For purposes of this Section 14, the term "Change in Control" shall mean any of the following events: (a) Any person, as such term is used in Rule 13d-5 promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or group, as defined in Sections 3(a)(9) and 13(d)(3) of the Exchange Act (each such person or group, an "SEC Person"), becomes the beneficial owner, as defined in Rule 13d-3 promulgated under the Exchange Act (a "Beneficial Owner"), of 20% or more of the then outstanding common stock of the Company or of the securities of the Company entitled to vote generally in the election of directors ("Voting Securities") representing 20% or more of the combined voting power of all the then outstanding Voting Securities (such an SEC Person, a "20% Owner"); provided, however, that for purposes of this subsection (a), the following acquisitions shall not constitute a Change in Control: (1) any acquisition directly from the Company (excluding any acquisition resulting from the exercise of an exercise, conversion or exchange privilege unless the security being so exercised, converted or exchanged was acquired directly from the Company), (2) any acquisition by the Company, (3) any acquisition by an employee benefit plan (or related trust) sponsored or maintained by the Company or any corporation controlled by the Company (a "Company Plan"), or (4) any acquisition by any corporation pursuant to a transaction which complies with clauses (i), (ii) and (iii) of subsection (c) of this definition; provided further, that for purposes of clause (2), if any 20% Owner of the Company other than the Company or any Company Plan becomes a 20% Owner by reason of an acquisition by the Company, and such 20% Owner of the Company shall, after such acquisition by the Company, become the beneficial owner of any additional outstanding common shares of the Company or any additional outstanding Voting Securities of the Company (other than pursuant to any dividend reinvestment plan or arrangement maintained by the A-6

Company) and such beneficial ownership is publicly announced, such additional beneficial ownership shall constitute a Change in Control; or (b) Individuals who, as of the effective date of the Plan, constitute the Board (the "Incumbent Board") cease for any reason to constitute at least a majority of the Incumbent Board; provided, however, that any individual becoming a director subsequent to the date hereof whose election, or nomination for election by the Company's shareholders, was approved by a vote of at least a majority of the directors then comprising the Incumbent Board shall be considered as though such individual were a member of the Incumbent Board, but excluding, for this purpose, any such individual whose initial assumption of office occurs as a result of an actual or threatened election contest (as such terms are used in Rule 14a-11 promulgated under the Exchange Act) or other actual or threatened solicitation of proxies or consents by or on behalf of a person other than the Board; or (c) Consummation of a reorganization, merger or consolidation ("Merger"), or the sale or other disposition of more than 50% of the operating assets of the Company (determined on a consolidated basis), other than in connection with a sale-leaseback or other arrangement resulting in the continued utilization of such assets (or the operating products of such assets) by the Company (such reorganization, merger, consolidation, sale or other disposition, a "Corporate Transaction"); excluding, however, a Corporate Transaction pursuant to which: (i) all or substantially all of the individuals and entities who are the Beneficial Owners, respectively, of the outstanding common stock of Company and outstanding Voting Securities of the Company immediately prior to such Corporate Transaction beneficially own, directly or indirectly, more than 60% of, respectively, the then-outstanding shares of common stock and the combined voting power of the then-outstanding voting securities entitled to vote generally in the election of directors, as the case may be, of the corporation resulting from such Corporate Transaction (including, without limitation, a corporation which, as a result of such transaction, owns the Company or all or substantially all of the assets of the Company either directly or through one or more subsidiaries) in substantially the same proportions as their ownership immediately prior to such Corporate Transaction of the outstanding common stock of Company and outstanding Voting Securities of the Company, as the case may be; (ii) no SEC Person (other than the corporation resulting from such Corporate Transaction, and any person which beneficially owned, immediately prior to such corporate Transaction, directly or indirectly, 20% or more of the outstanding common stock of the Company or the outstanding Voting Securities of the Company, as the case may be) becomes a 20% Owner, directly or indirectly, of the then-outstanding common stock of the corporation resulting from such Corporate Transaction or the combined voting power of the outstanding voting securities of such corporation; and A-7

(iii) individuals who were members of the Incumbent Board will constitute at least a majority of the members of the board of directors of the corporation resulting from such Corporate Transaction; or (d) Approval by the Company's shareholders of a plan of complete liquidation or dissolution of the Company, other than a plan of liquidation or dissolution which results in the acquisition of all or substantially all of the assets of the Company by an affiliated company. 15. Rules for Non-United States Jurisdictions. The Plan Administrator may establish rules or procedures relating to the operation and administration of the Plan to accommodate specific requirements of applicable local laws and procedures, including, without limitation, rules and procedures governing payroll deductions, payment of interest, conversion of local currency, payroll tax, withholding procedures and handling of stock certificates which vary with local requirements. The Plan Administrator may also adopt sub-plans applicable to particular Participating Companies or locations, which sub-plans may be designed to be outside the scope of section 423 of the Code. The rules of such sub-plans may take precedence over the provisions of this Plan, with the exception of Section 4, but unless otherwise superceded by the terms of such sub-plan, the provisions of this Plan shall govern the operation of such sub-plan. 16. No Enlargement of Employee Rights. Nothing contained in this Plan shall be deemed to give any Eligible Employee the right to continued employment with the Company or any Subsidiary Company or to interfere with the right of the Company or any Subsidiary Company to discharge any Eligible Employee at any time. 17. Governing Law. This Plan, any related agreements (such as an enrollment form), and all determinations made and actions taken pursuant thereto, to the extent not otherwise governed by the Code or the law of the United States, shall be governed by the laws of the state of Pennsylvania and construed in accordance therewith without giving effect to principles of conflicts of law. A-8

                                                                     EXHIBIT 5.1

                           Sidley Austin Brown & Wood
                                 Bank One Plaza
                            10 South Dearborn Street
                             Chicago, Illinois 60603



                                  May 22, 2001


Exelon Corporation
10 South Dearborn Street - 37th Floor
Chicago, Illinois  60680-5379


Ladies and Gentlemen:

                  We refer to the Registration Statement on Form S-8 (the
"Registration Statement") being filed by Exelon Corporation, a Pennsylvania
corporation (the "Company"), with the Securities and Exchange Commission (the
"Commission") under the Securities Act of 1933, as amended (the "Securities
Act"), relating to the registration of 2,000,000 shares of common stock, no par
value (the "New Shares"), of the Company to be issued pursuant to the Exelon
Corporation Employee Stock Purchase Plan (the "Plan").

                  We are familiar with the Articles of Incorporation and By-laws
of the Company currently in effect and the resolutions adopted to date by the
Board of Directors of the Company relating to the Plan and the Registration
Statement. We also have examined originals, or copies of originals certified or
otherwise identified to our satisfaction, of such records of the Company and
other corporate documents, have examined such questions of law and have
satisfied ourselves as to such matters of fact as we have considered relevant
and necessary as a basis for the opinions set forth herein. We have assumed the
authenticity of all documents submitted to us as originals, the genuineness of
all signatures, the legal capacity of all natural persons and the conformity
with the original documents of any copies thereof submitted to us for our
examination.

                  Based on the foregoing, we are of the opinion that each New
Share will be legally issued, fully paid and non-assessable when (i) the
Registration Statement, as it may be amended, shall have become effective under
the Securities Act, (ii) such New Share shall have been duly issued pursuant to
the authorization of the Company's Board of Directors and (iii) such New Share
shall have been delivered to the purchaser thereof against payment of the agreed
consideration thereof determined in accordance with the terms of the Plan.

                  We hereby consent to the filing of this opinion letter with
the Commission as Exhibit 5.1 to the Registration Statement. In giving this




Exelon Corporation May 22, 2001 Page 2 consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission. The foregoing opinions are limited to the substantive laws of the Commonwealth of Pennsylvania and the federal laws of the United States of America. We assume no obligation to supplement this opinion if any applicable law changes after the date hereof or if we become aware of any fact that might change the opinion expressed herein after the date hereof. We do not find it necessary for the purposes of the opinions expressed in this opinion letter, and accordingly we do not purport to cover herein, the application of the securities or "Blue Sky" laws of the various states to the issuance of the New Shares. Very truly yours, /s/ SIDLEY AUSTIN BROWN & WOOD





                                                                    EXHIBIT 23.1

                                    [FORM OF]


                       CONSENT OF INDEPENDENT ACCOUNTANTS


We hereby consent to the incorporation by reference in this Registration
Statement on Form S-8 of our report dated January 30, 2001, except for Note 21
PETT Refinancing for which the date is March 1, 2001, relating to the financial
statements of Exelon Corporation which appears in the Current Report on Form 8-K
dated March 16, 2001, which is incorporated by reference in Exelon Corporation's
Annual Report on Form 10-K for the year ended December 31, 2000. We also consent
to the incorporation by reference of our report dated January 30, 2001 relating
to the financial statement schedule, which appears in such Annual Report on Form
10-K.



PricewaterhouseCoopers LLP

Chicago, Illinois
May 22, 2001

                                                                    EXHIBIT 24.1

                            FORM OF POWER OF ATTORNEY


         KNOW ALL PERSONS BY THESE PRESENTS, that the undersigned, a Director of
Exelon Corporation, a Pennsylvania corporation, does hereby constitute and
appoint Corbin A. McNeill, Jr. and John W. Rowe and each or any one of them, his
true and lawful attorneys-in-fact and agents, with full power of substitution
and resubstitution, for him or her and in his or her name, place and stead, in
any and all capacities, to sign a registration statement under the Securities
Act of 1933 relating to the registration of shares of common stock, no par
value, of Exelon Corporation for issuance under the Exelon Corporation Employee
Stock Purchase Plan and any and all amendments (including post-effective
amendments) or supplements to such registration statement and any registration
statement relating to any offering made pursuant to such registration statement
that is to be effective upon filing pursuant to Rule 462(b) under the Securities
Act, and to file the same, with all exhibits thereto, and other documents in
connection therewith, with the SEC, granting unto said attorneys-in-fact and
agents, and each of them, full power and authority to perform each and every act
and thing requisite and necessary to be done in connection therewith, as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that said attorneys-in-fact and agents, or any of them, or
his or their substitute or substitutes, may lawfully do or cause to be done by
virtue hereof.

         IN WITNESS WHEREOF, I have hereunto set my hand this ____ day of May,
2001.



                          ____________________________