Third Amendment to Dynegy Inc. 401(K) Savings Plan, effective October 1,2003




 EXHIBIT 10.21 
  
 THIRD AMENDMENT TO 
 DYNEGY INC. 401(K) SAVINGS PLAN 
  
 WHEREAS,
Dynegy Inc. (the “Company”) and other Employers have heretofore adopted the Dynegy Inc. 401(k) Savings Plan (the “Plan”) for the benefit of their eligible employees; and 
  
 WHEREAS, the Company amended and restated the Plan on behalf of itself
and the other Employers, effective as of January 1, 2002; and 
  
 WHEREAS, the Company desires to further amend the Plan on behalf of itself and the other Employers; 
  
 NOW, THEREFORE, the Plan shall be amended as follows, effective for payroll periods ending on or after October 1, 2003: 
  
 1. Sections 3.3 and 3.4 of the Plan shall be deleted and the
following shall be substituted therefor: 
  
 “3.3
Employer Matching Contributions. 
  
 (a) For each payroll period, the Employer shall contribute to the Trust, as Employer Matching Contributions, an amount that equals 100% of the Before-Tax Contributions that were made pursuant to Section 3.1 on behalf of each of the Members
during such payroll period and that were not in excess of 5% of each such Member’s Compensation for such payroll period. 
  
 (b) In addition to the Employer Matching Contributions made pursuant to Paragraph (a) above, for each Plan Year the Employer shall
contribute to the Trust, as Employer Matching Contributions, an amount equal to the difference, if any, between (1) 100% of the Before-Tax Contributions that were made pursuant to Section 3.1 on behalf of each of the Eligible Members during such
Plan Year and that were not in excess of 5% of each such Eligible Member’s Compensation for such Plan Year and (2) the Employer Matching Contributions made pursuant to Paragraph (a) above for each such Eligible Member for such Plan Year. For
purposes of this Paragraph, the term “Eligible Member” shall mean each Member who was an Eligible Employee on the last day of the applicable Plan Year. 
  
 (c) Employer Matching Contributions pursuant to Paragraph (a) above shall be contributed to the Trust at the
same time the related Before-Tax Contributions are contributed to the Trust, and Employer Matching Contributions pursuant to Paragraph (b) above shall be contributed to the Trust at the time determined by the Committee. At the sole discretion of the
Directors or the Compensation Committee of the Company’s Board of Directors, Employer Matching Contributions on behalf of Participants shall be made in cash, in whole shares of Company Stock, or in any combination of cash and whole shares of
Company Stock. 








 3.4 Employer Discretionary Contributions. For each Plan Year, the Employer
may contribute to the Trust, as an Employer Discretionary Contribution, an additional amount as determined in its discretion. If it has been so determined that an Employer Discretionary Contribution shall be made for any Plan Year, then such
contribution shall be made in cash, in whole shares of Company Stock, or in any combination of cash and whole shares of Company Stock (as determined in the sole discretion of the Directors or the Compensation Committee of the Company’s Board of
Directors).” 
  
 2. As amended hereby, the Plan is
specifically ratified and reaffirmed. 
  
 IN WITNESS
WHEREOF, the undersigned has caused these presents to be executed this 17th day of October, 2003. 
  

			
	DYNEGY INC.
		
	BY:	 	 /s/ Teresa L. Naylor


	 	 	 Name: Teresa L. Naylor
 Title: