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

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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(Print or Type Responses)
1. Name and Address of Reporting Person *
COLLINS JOHN C
  2. Issuer Name and Ticker or Trading Symbol
CONSTELLATION ENERGY GROUP INC [CEG]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
CRO, Sr. VP - CEG
(Last)
(First)
(Middle)
750 E. PRATT STREET
3. Date of Earliest Transaction (Month/Day/Year)
02/15/2005
(Street)

BALTIMORE, MD 21202
4. If Amendment, Date Original Filed(Month/Day/Year)
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 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 Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 02/15/2005   M   16,533 A (1) $ 34.25 39,059.595 D  
Common Stock 02/15/2005   S   16,533 D (1) $ 53.1275 22,526.595 D  
Common Stock 02/15/2005   M   20,000 A (1) $ 25.08 42,526.595 D  
Common Stock 02/15/2005   S   20,000 D (1) $ 53.1275 22,759 (2) D  
Common Stock               3,492.268 (3) I By 401(k) Plan
Common Stock               1,000 I By Son
Common Stock               1,000 I By Daughter

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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 Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Stock options (right to buy) (4) $ 34.25 02/15/2005   M     16,533   (5) 05/18/2010 Common Stock 16,533 $ 0 0 D  
Stock options (right to buy) (4) $ 25.08 02/15/2005   M     20,000   (6) 11/12/2011 Common Stock 20,000 $ 0 0 D  
Stock options (right to buy) (4) $ 39.63 02/26/2004   A   21,650     (7) 02/26/2014 Common Stock 21,650 $ 0 21,650 D  
Stock options (right to buy) (4) $ 28.81 05/02/2003   A   23,290     (8) 05/02/2013 Common Stock 23,290 $ 0 23,290 D  
Stock options (right to buy) (4) $ 31.21 05/24/2002   A   50,000     (9) 05/24/2012 Common Stock 50,000 $ 0 50,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
COLLINS JOHN C
750 E. PRATT STREET
BALTIMORE, MD 21202
      CRO, Sr. VP - CEG  

Signatures

 John R. Collins   02/16/2005
**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) This transaction involved the cashless exercise of stock options and the subsequent sale of the underlying common stock.
(2) This amount includes shares obtained through reinvested dividends since the Form 4 filed on 5/4/04.
(3) This amount includes 193.585 shares acquired since the Form 4 filed on 5/4/04.
(4) These are employee stock options.
(5) Options vested in three equal annual installments on 5/18/01, 5/18/02, and 5/18/03.
(6) Options vested in two installments - 8,000 on 7/1/02 and 12,000 on 7/1/03.
(7) Options vest in three equal annual installments on 2/26/05, 2/26/06, and 2/26/07.
(8) Options vest in three equal annual installments beginning on 5/2/04. The first installment vested on 5/2/04, and the second and third installments vest on 5/2/05 and 5/2/06.
(9) Options vest in three equal annual installments beginning on 5/24/03. The first two installments vested on 5/24/03 and 5/24/04, and the third installment will vest on 5/24/05.

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