Ownership Submission
FORM 5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Form 3 Holdings Reported
Form 4 Transactions Reported
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

ANNUAL STATEMENT OF CHANGES IN 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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1. Name and Address of Reporting Person *
Thayer Jonathan W
2. Issuer Name and Ticker or Trading Symbol
EXELON CORP [EXC]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Senior EVP and CFO
(Last)
(First)
(Middle)

10 SOUTH DEARBORN STREET, 54TH FLOOR
3. Statement for Issuer's Fiscal Year Ended (Month/Day/Year)
12/31/2017
(Street)


CHICAGO, IL 60603
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Reporting
(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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned at end of Issuer's Fiscal Year
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Amount (A) or (D) Price
Common Stock             33,473 D  
Common Stock (401k Shares)             1,838 (1) I By 401k Plan

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 2270 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned at End of Issuer's Fiscal Year
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
(A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stock Unit Awards $ 0             (2)   (2) Common Stock
58,727
  58,727 (3)
D
 
Restricted Stock Unit Grant 01/28/2013 $ 0             (4)   (4) Common Stock
30,000
  30,000
D
 
NQ Stock Option 03/12/2012 $ 39.81             (5)   (5) Common Stock
97,000
  97,000
D
 
NQ Stock Option 02/24/2012 $ 39.24             (6)   (6) Common Stock
175,946
  175,946
D
 
NQ Stock Option 02/25/2011 $ 32.46             (6)   (6) Common Stock
125,429
  125,429
D
 
NQ Stock Option 02/26/2010 $ 37.71             (6)   (6) Common Stock
67,304
  67,304
D
 
NQ Stock Option 02/21/2008 $ 101.05             (6)   (6) Common Stock
8,676
  8,676
D
 

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Thayer Jonathan W
10 SOUTH DEARBORN STREET
54TH FLOOR
CHICAGO, IL 60603
      Senior EVP and CFO  

Signatures

Scott N. Peters, Esq. Attorney in Fact for Jonathan Thayer 01/19/2018
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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) Shares held as of December 31, 2017 in a multi-fund 401(k) Plan to be settled in 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.
(2) Restricted stock unit awards made pursuant to the Exelon Long Term Incentive Plan. Share awards are made annually in January at the Compensation and Leadership Development committee's meeting and vest in 1/3 increments on the date of the committee's January meeting in the first, second and third years after the award was made.
(3) Balance consists of unvested shares remaining from the awards granted in January of the previous three years along with shares acquired through automatic dividend reinvestment as follows: 517, 512, 496 and 465 shares acquired on March 10, 2017, June 9, 2017, September 8, 2017 and December 9, 2017 respectively.
(4) Restricted stock grant made pursuant to the Exelon Long Term Incentive Plan. 100% of the shares will vest on January 28, 2018.
(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.
(6) Non-qualified employee stock options originally granted by Constellation Energy Group that vested and were converted pursuant to the Merger Agreement. Each Constellation option was converted into an option to purchase Exelon common stock at the rate of 0.93 shares of Exelon common stock for each share of Constellation common stock at a strike price equal to the quotient of the original Constellation strike price and 0.93. The grant is fully vested and will expire on the tenth anniversary of the grant date referenced in Column 1.

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