Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  GLACE JOSEPH R
2. Date of Event Requiring Statement (Month/Day/Year)
03/12/2012
3. Issuer Name and Ticker or Trading Symbol
EXELON CORP [EXC]
(Last)
(First)
(Middle)
10 SOUTH DEARBORN STREET, 54TH FLOOR
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP and Chief Risk Officer
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

CHICAGO, IL 60603
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common stock 613
D
 
Common Stock (ESPP) 741
D
 
Common stock (IRA) 200
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted stock units- 07/01/2008   (1)   (1) Common stock 3,500 $ (1) D  
Performance Shares - Stock Units   (2)   (2) Common Stock 1,294 $ (2) D  
Restricted stock units- key manager program   (3)   (3) Common Stock 1,171 $ (3) D  
Deferred Comp. Phantom Shares   (4)   (4) Common stock 400 $ (4) D  
NQ Stock Options - 01/26/2004   (5)   (5) Common Stock 10,327 $ 32.54 D  
NQ Stock Options - 01/24/2005   (5)   (5) Common Stock 7,600 $ 42.85 D  
NQ Stock Options - 01/23/2006   (5)   (5) Common Stock 6,700 $ 58.55 D  
NQ Stock Options - 01/22/2007   (5)   (5) Common Stock 4,000 $ 59.96 D  
NQ Stock Options - 01/28/2008   (5)   (5) Common Stock 3,400 $ 73.29 D  
NQ Stock Options - 01/26/2009   (5)   (5) Common Stock 4,300 $ 56.51 D  
NQ Stock Options - 01/25/2010   (5)   (5) Common Stock 3,800 $ 46.09 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
GLACE JOSEPH R
10 SOUTH DEARBORN STREET
54TH FLOOR
CHICAGO, IL 60603
      SVP and Chief Risk Officer  

Signatures

Scott N. Peters, attorney in fact for Joseph R. Glace 03/13/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Restricted stock units granted under the Issuer's Long Term Incentive Plan. Restricted stock units may be settled on a 1 for 1 basis in shares of Exelon common stock. 100% of the shares will vest on 07/01/2012.
(2) Performance Shares awarded pursuant to the Exelon Long Term Incentive Plan. 1/3 of the shares awarded vested immediately upon receipt. The remaining shares vest in 1/3 increments on each of the first and second anniversaries of the grant date.
(3) Restricted stock units awarded pursuant to the Exelon Long Term Incentive Plan. 1/3 of the shares awarded vest on each of the first, second and third anniversaries of the grant date. Under certain circumstances some or all of the vested shares may be settled in cash on a 1 for 1 basis based on the cash value of the underlying stock on the date of vesting.
(4) Phantom shares held in a multi-fund deferred compensation plan to be settled for cash upon the reporting person's termination of employment for any reason on a 1:1 basis. Shares are acquired through regular periodic contributions, company matching contributions, and the automatic reinvestment of dividends.
(5) Non qualified employee stock options, awarded pursuant to the Exelon Long Term Incentive Plan. Options vest in 1/4 increments on each of the first four anniversaries of the grant date, referenced in column one, and expire on the tenth anniversay of the grant date.

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