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
OMB APPROVAL
OMB Number: 3235-0104
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
  Alonso Mario E
 2. Date of Event Requiring Statement (Month/Day/Year)
06/14/2012		 3. Issuer Name and Ticker or Trading Symbol
DYNEGY INC. [DYN]
(Last)
(First)
(Middle)
601 TRAVIS, 14TH FLOOR		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
VP-Strategic Planning & Dev
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

HOUSTON, TX 77002		 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 9,980 (1)
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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.

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
Employee Stock Option (Right to Buy)   (2) 02/10/2014 Common Stock 670 $ 22.4 D  
Employee Stock Option (Right to Buy)   (3) 01/19/2015 Common Stock 710 $ 21.5 D  
Employee Stock Option (Right to Buy)   (4) 03/06/2018 Common Stock 2,148 $ 37.4 D  
Employee Stock Option (Right to Buy)   (5) 03/04/2019 Common Stock 17,273 $ 5.65 D  
Employee Stock Option (Right to Buy)   (6) 03/03/2020 Common Stock 11,294 $ 7.2 D  
Phantom Stock Units   (7)   (7) Common Stock 28,250 $ (7) D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Alonso Mario E
601 TRAVIS
14TH FLOOR
HOUSTON, TX 77002		       VP-Strategic Planning & Dev  

Signatures

/s/ Heidi D. Lewis, Attorney-in-Fact 06/22/2012
**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) Includes 6666 shares of restricted stock which vest in full on March 3, 2013.
(2) The options became exerciseable in three equal installments beginning February 10, 2005.
(3) The options became exerciseable in three equal installments beginning January 19, 2006.
(4) The options became exerciseable in three equal installments beginning March 6, 2009.
(5) The options became exerciseable in three equal installments beginning March 4, 2010.
(6) The options became exerciseable as to 3,765 shares on March 3, 2011 and as to an additional 3,765 shares on March 3, 2012. The remaining become exerciseable beginning March 3, 2013.
(7) Each unit of phantom stock is the economic equivalent of one share of common stock. 14,125 units of phantom stock become payable in cash within 30 days after the vesting date, March 7, 2013, and as to the remaining 14,125 phantom stock units become payable in cash within 30 days after the vesting date, March 7, 2014.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.