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UNITED STATES OF AMERICA
BEFORE THE
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

The AES Corporation

)

File No. 70-9779

Certificate Pursuant to Rule 24 and Release No. 35-27363
Under the Public Utility Holding Company Act of 1935

        On March 23, 2001, the Securities and Exchange Commission ("SEC") issued an order, Release No. 35-27363 in File No. 70-9779 ("Exemption Order"), granting an exemption under Section 3(a) of the Public Utility Holding Company Act of 1935, as amended, to The AES Corporation ("AES") in relation to its proposed acquisition of IPALCO Enterprises, Inc. ("IPALCO"), which has a public-utility subsidiary company, Indianapolis Power & Light Company ("IPL"). The Exemption Order required AES to file certain certificates (as described in the Exemption Order) under Rule 24 within 60 days of the close of each calendar quarter for a period of two years beginning March 31, 2001 and every six months thereafter. A certificate complying with the Exemption Order is set forth below (as an attachment) for the period ending March 31, 2005.

Dated: May 31, 2005

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The AES Corporation
SEC Filing Pursuant to Section 3(a)(5) Exemption Order
Period Ended March 31, 2005

Item (1) per Exemption Order (statements attached):

1)

Pro Rata Consolidated Statement of Operations of The AES Corporation for the 12 months ended March 31, 2005

2)

Pro Rata Consolidated Balance Sheet of The AES Corporation at March 31, 2005

3)

Statement of Consolidated Income of IPALCO for the 12 months March 31, 2005

4)

Statement of Income of IPL for the 12 months ended March 31, 2005

5)

Consolidated Balance Sheet of IPALCO at March 31, 2005

6)

Balance Sheet of IPL at March 31, 2005

2

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THE AES CORPORATION

CONSOLIDATED STATEMENT OF OPERATIONS
(INCLUDES IPALCO)
FOR THE TWELVE MONTHS ENDED MARCH 31, 2005
PRO RATA BASIS(1)
(Unaudited)

		Twelve Months Ended 3/31/2005
		($ in millions)
REVENUES:
Sales and services		$	7,081
OPERATING COSTS AND EXPENSES:
Cost of sales and services			4,925
Selling, general and administrative expenses			169
Total operating costs and expenses			5,094
OPERATING INCOME			1,987
OTHER INCOME AND (EXPENSE):
Interest expense, net			(1,318	)
Other income (expense), net			57
Foreign currency transaction losses			(122	)
INCOME BEFORE INCOME TAXES			604
Income tax (benefit) expense			179
INCOME FROM CONTINUING OPERATIONS			425
Income from operations of discontinued components (net of income taxes)			46
NET INCOME		$	471

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(1)

In accordance with the analysis used in the order requiring filing of this certificate, this table is calculated on a proportional consolidation basis whereby AES' subsidiaries are included by multiplying each applicable line item from the statement of operations of each AES subsidiary times AES' percentage ownership interest in such subsidiary.

3

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THE AES CORPORATION

CONSOLIDATED BALANCE SHEET
(INCLUDES IPALCO)
MARCH 31, 2005
($ in millions, unaudited)

ASSETS
Current Assets:
	Cash and cash equivalents		$	1,555
	Restricted cash			334
	Short-term investments			57
	Accounts receivable, net of reserves			1,547
	Inventory			413
	Deferred income taxes—current			193
	Prepaid expenses			116
	Other current assets			681
	Total current assets			4,896
Property, Plant and Equipment:
	Land			783
	Electric generation and distribution assets			22,463
	Accumulated depreciation and amortization			(5,530	)
	Construction in progress			1,107
	Property, plant and equipment, net			18,823
Other Assets:
	Deferred financing costs—net			496
	Investments in and advances to affiliates			684
	Debt service reserves and other deposits			678
	Goodwill—net			1,422
	Deferred income taxes—noncurrent			798
	Other assets			1,866
	Total other assets			5,944
	Total assets		$	29,663

4

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THE AES CORPORATION

CONSOLIDATED BALANCE SHEET
(INCLUDES IPALCO)
MARCH 31, 2005
($ in millions, unaudited)

LIABILITIES & STOCKHOLDERS' EQUITY
Current liabilities:
	Accounts payable		$	1,106
	Accrued interest			409
	Accrued and other liabilities			1,686
	Recourse debt—current portion			146
	Non-recourse debt—current portion			1,748
	Total current liabilities			5,095
Long-term Liabilities:
	Recourse debt			5,016
	Non-recourse debt			11,435
	Deferred income taxes			729
	Pension liabilities and other-post retirement liabilities			869
	Other long-term liabilities			3,108
	Total long-term liabilities			21,157
	Minority interest			1,663
Stockholders' Equity:
	Common stock—$.01 par value—1,200 million shares authorized, 653 million shares issued and outstanding			7
	Additional paid-in capital			6,368
	Accumulated deficit			(680	)
	Accumulated other comprehensive loss			(3,947	)
	Total stockholders' equity			1,748
	Total		$	29,663

5

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IPALCO ENTERPRISES, INC. and SUBSIDIARIES
Consolidated Statement of Income
($ In Thousands)
(Unaudited)

For the Twelve Months Ended March 31, 2005
ELECTRIC UTILITY OPERATING REVENUES				$	897,006
UTILITY OPERATING EXPENSES:
	Operation:
		Fuel			192,302
		Other operating expenses			136,597
	Power purchased				16,694
	Maintenance				76,236
	Depreciation and amortization				129,629
	Taxes other than income taxes				34,978
	Income taxes—net				95,242
		Total operating expenses			681,678
UTILITY OPERATING INCOME					215,328
OTHER INCOME AND (DEDUCTIONS):
	Allowance for equity funds used during construction				1,396
	Loss on sales of assets, net				(2	)
	Other—net				(2,878	)
	Income tax benefit—net				28,191
		Total other income (deductions)—net			26,707
INTEREST AND OTHER CHARGES:
	Interest on long-term debt				112,922
	Other interest				604
	Allowance for borrowed funds used during construction				(1,563	)
	Amortization of redemption premiums and expense on debt-net				2,683
	Preferred dividends of subsidiary				3,213
		Total interest and other charges—net			117,859
NET INCOME				$	124,176

6

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INDIANAPOLIS POWER & LIGHT COMPANY
Statement of Income
($ In Thousands)
(Unaudited)

For the Twelve Months Ended March 31, 2005
OPERATING REVENUES				$	897,006
OPERATING EXPENSES:
	Operation:
		Fuel			192,302
		Other			136,597
	Power purchased				16,694
	Maintenance				76,236
	Depreciation and amortization				129,629
	Taxes other than income taxes				34,978
	Income taxes—net				95,242
		Total operating expenses			681,678
OPERATING INCOME					215,328
OTHER INCOME AND (DEDUCTIONS):
	Allowance for equity funds used during construction				1,396
	Loss on sales of assets—net				(2	)
	Miscellaneous income and (deductions)—net				(1,102	)
	Income taxes applicable to nonoperating income				1,290
		Total other income and (deductions)—net			1,582
INTEREST AND OTHER CHARGES:
	Interest on long-term debt				49,170
	Other interest				607
	Allowance for borrowed funds used during construction				(1,563	)
	Amortization of redemption premium and expense on debt—net				1,611
		Total interest and other charges—net			49,825
NET INCOME					167,085
PREFERRED DIVIDEND REQUIREMENTS					3,213
INCOME APPLICABLE TO COMMON STOCK				$	163,872

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IPALCO ENTERPRISES, INC. and SUBSIDIARIES
Consolidated Balance Sheet
($ In Thousands)
(Unaudited)

					March 31, 2005
ASSETS
UTILITY PLANT:
	Utility plant in service				$	3,424,936
	Less accumulated depreciation					1,380,256
		Utility plant in service—net				2,044,680
	Construction work in progress					102,141
	Property held for future use					1,085
		Utility plant—net				2,147,906
OTHER ASSETS:
	Nonutility property—at cost, less accumulated depreciation					1,496
	Other investments					8,461
		Other assets—net				9,957
CURRENT ASSETS:
	Cash and cash equivalents					6,121
	Short term investments					41,900
	Accounts receivable and unbilled revenue (less allowance for doubtful accounts of $2,575)					49,191
	Fuel—at average cost					18,864
	Materials and supplies—at average cost					51,552
	Prepayments and other current assets					6,741
		Total current assets				174,369
DEFERRED DEBITS:
	Regulatory assets					133,026
	Miscellaneous					31,973
		Total deferred debits				164,999
			TOTAL		$	2, 497,231

8

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IPALCO ENTERPRISES, INC. and SUBSIDIARIES
Consolidated Balance Sheet
($ In Thousands)
(Unaudited)

					March 31, 2005
CAPITALIZATION AND LIABILITIES
CAPITALIZATION:
	Common shareholder's deficit:
		Premium on 4% cumulative preferred stock			$	649
		Paid in capital				961
		Accumulated deficit				(73,429	)
		Accumulated other comprehensive loss				(51,418	)
			Total common shareholder's deficit			(123,237	)
		Cumulative preferred stock of subsidiary				59,135
		Long-term debt (less current maturities and sinking fund requirements)				1,502,062
			Total capitalization			1,437,960
CURRENT LIABILITIES:
	Accounts payable					35,881
	Accrued expenses					18,231
	Dividends payable					803
	Accrued real estate and personal property taxes					20,031
	Accrued income and other taxes					34,874
	Accrued interest					38,749
	Customer deposits					12,312
	Other current liabilities					4,237
			Total current liabilities			165,118
DEFERRED CREDITS AND OTHER LONG-TERM LIABILITIES:
	Accumulated deferred income taxes—net					352,681
	Regulatory liabilities and other removal costs					388,661
	Unamortized investment tax credit					24,803
	Accrued postretirement benefits					7,215
	Accrued pension benefits					108,994
	Miscellaneous					11,799
			Total deferred credits and other long-term liabilities			894,153
TOTAL					$	2,497,231

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INDIANAPOLIS POWER & LIGHT COMPANY
Balance Sheet
($ In Thousands)
(Unaudited)

					March 31, 2005
ASSETS
UTILITY PLANT:
	Utility plant in service				$	3,424,936
	Less accumulated depreciation					1,380,256
		Utility plant in service—net				2,044,680
	Construction work in progress					102,141
	Property held for future use					1,085
		Utility plant—net				2,147,906
OTHER PROPERTY—
	At cost, less accumulated depreciation					2,509
CURRENT ASSETS:
	Cash and cash equivalents					5,185
	Short term investments					40,600
	Accounts receivable and unbilled revenue (less allowances for doubtful accounts of $2,561)					49,120
	Fuel—at average cost					18,864
	Materials and supplies—at average cost					51,552
	Prepayments and other current assets					6,741
		Total current assets				172,062
DEFERRED DEBITS:
	Regulatory assets					133,026
	Miscellaneous					25,429
		Total deferred debits				158,455
			TOTAL		$	2,480,932

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INDIANAPOLIS POWER & LIGHT COMPANY
Balance Sheet
($ In Thousands)
(Unaudited)

					March 31, 2005
CAPITALIZATION AND LIABILITIES
CAPITALIZATION:
	Common shareholder's equity:
		Common stock			$	324,537
		Premium on 4% cumulative preferred stock				2,642
		Paid in capital				961
		Retained earnings				351,559
		Accumulated other comprehensive loss				(51,415	)
			Total common shareholder's equity			628,284
		Cumulative preferred stock				59,135
		Long-term debt				752,062
			Total capitalization			1,439,481
CURRENT LIABILITIES:
	Accounts payable					35,881
	Accrued expenses					17,971
	Dividends payable					803
	Accrued real estate and personal property taxes					20,028
	Accrued income taxes					45,504
	Accrued interest					14,632
	Customer deposits					12,312
	Other current liabilities					1,075
			Total current liabilities			148,206
DEFERRED CREDITS AND OTHER LONG-TERM LIABILITIES:
	Accumulated deferred income taxes—net					351,773
	Regulatory liabilities and other removal costs					388,661
	Unamortized investment tax credit					24,803
	Accrued postretirement benefits					7,215
	Accrued pension benefits					108,994
	Miscellaneous					11,799
			Total deferred credits and other long-term liabilities			893,245
TOTAL					$	2,480,932

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Item (2) per Exemption Order (Income Statement Amounts are 12 months ended):

IPL Contributions To
AES/IPALCO Consolidated Holding Company
(Pro Rata Consolidation Basis(1))
($MM)

		12 Mos. ended 3/31/04		12 Mos. ended 3/31/05
Gross Revenues(2)		10.06	%	12.67	%
IPL		827		897
IPALCO (excluding IPL)		0		0
AES		7,396		6,184
AES/IPALCO		8,223		7,081
Operating Income		12.46	%	15.65	%
IPL		279		311
IPALCO (excluding IPL)		0		0
AES		1,961		1,676
AES/IPALCO		2,240		1,987
Net Income (Loss)		(31.70	%)	34.82	%
IPL		142		164
IPALCO (excluding IPL)		(40	)	(40	)
AES		(550	)	347
AES/IPALCO		(448	)	471
Net Assets		8.40	%	8.42	%
IPL		2,497		2,481
IPALCO (excluding IPL)		16		16
AES		27,221		27,166
AES/IPALCO		29,734		29,663

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(1)

In accordance with the analysis used in the order requiring filing of this certificate, the AES line items in this table are calculated on a proportional consolidation basis whereby AES' subsidiaries are included by multiplying each applicable line item from the statement of operations or balance sheet, as applicable, of each AES subsidiary times AES' percentage ownership interest in such subsidiary.

(2)

Gross business revenues (utility and non-utility) of IPALCO combined as a percentage of total gross business revenues (including IPALCO/IPL, utility and non-utility) of AES.

12

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Item (3) per Exemption Order—Generation Information:

        AES Generating Plants in Operation at March 31, 2005 (excluding IPALCO):

Unit		Country		Capacity (rounded) (MW)		AES Interest (rounded) (%)		AES Equity (rounded) (MW)		Regulatory Status
Deepwater		USA		160		100		160		QF
Beaver Valley		USA		125		100		125		QF
Placerita		USA		120		100		120		QF
Thames		USA		181		100		181		QF
Shady Point		USA		320		100		320		QF
Hawaii		USA		203		100		203		QF
Warrior Run		USA		180		100		180		QF
Somerset		USA		675		100		675		EWG
Cayuga		USA		306		100		306		EWG
Greenidge		USA		161		100		161		EWG
Westover		USA		126		100		126		EWG
Alamitos		USA		1,986		100		1,986		EWG
Redondo Beach		USA		1,334		100		1,334		EWG
Huntington Beach		USA		904		100		904		EWG
Hemphill		USA		14		67		9		QF
Mendota		USA		25		100		25		QF
Delano		USA		50		100		50		QF
Puerto Rico		USA		454		100		454		FUCO
Ironwood		USA		705		100		705		EWG
Red Oak		USA		832		100		832		EWG
Altech III		USA		35		78		27		QF
San Jacinto		USA		18		29		5		QF
Altamont (7 projects)		USA		25		100		25		QF
Condon		USA		50		39		20		EWG
DOMESTIC SUBTOTAL:				8,989				8,933

Unit		Country		Capacity (MW)		AES Interest (%)		AES Equity (MW)		Regulatory Status
Kingston		Canada		110		50		55		EWG
San Nicolas		Argentina		650		96		624		EWG
Cabra Coral		Argentina		102		98		100		FUCO
El Tunal		Argentina		10		98		10		FUCO
Sarmiento		Argentina		33		98		32		FUCO
Ullum		Argentina		45		98		44		FUCO
Quebrada de Ullum		Argentina		45		Mgmt		0		FUCO

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Alicura		Argentina		1,040		96		998		FUCO
Bayano		Panama		260		49		127		FUCO
Panama		Panama		43		49		21		FUCO
Chiriqui—Esti		Panama		120		49		59		FUCO
Chiriqui—La Estrella		Panama		42		49		21		FUCO
Chiriqui—Los Valles		Panama		48		49		24		FUCO
Los Mina		Dom. Rep.		210		100		210		EWG
Cili		China		26		51		13		FUCO
Wuhu		China		250		25		63		FUCO
Chengdu Lotus City		China		48		35		17		FUCO
Jiaozuo		China		250		70		175		FUCO
Hefei		China		115		70		81		FUCO
Aixi		China		51		71		36		FUCO
Yangcheng		China		2,100		25		525		FUCO
Ekibastuz		Kazakhstan		4,000		100		4,000		FUCO
Ust-Kamenogorsk		Kazakhstan		331		100		331		FUCO
Shulbinsk		Kazakhstan		702		100		702		FUCO
Ust-Kamenogorsk CHP		Kazakhstan		1,356		100		1,356		FUCO
Sogrinsk CHP		Kazakhstan		301		100		301		FUCO
Kamenogorsk Heat Nets		Kazakhstan		260		Mgmt		0		FUCO
OPGC		India		420		49		206		FUCO
Lal Pir		Pakistan		365		55		201		FUCO
Pak Gen		Pakistan		365		55		201		FUCO
Borsod		Hungary		96		100		96		FUCO
Tisza II		Hungary		860		100		860		FUCO
Tiszapalkonya		Hungary		125		100		125		FUCO
Elsta		Netherlands		630		50		315		FUCO
Indian Queens		U.K.		140		100		140		EWG
Kilroot		U.K.		520		97		504		FUCO
Uruguaiana		Brazil		639		46		294		FUCO
Tietê (10 plants)		Brazil		2,650		24		636		FUCO
EDC (5 plants)		Venezuela		2,616		86		2,250		FUCO
Merida III		Mexico		495		55		272		FUCO
Ottana		Italy		140		100		140		FUCO
Chivor		Colombia		1,000		99		990		FUCO
Gener-Electrica de Santiago (2 plants)		Chile		479		89		426		FUCO
Gener-Energia Verde (3 plants)		Chile		42		99		42		FUCO
Gener-Guacolda		Chile		304		49		149		FUCO
Gener-Norgener		Chile		277		99		274		FUCO
Itabo (5 plants)		Dom. Rep.		586		25		147		FUCO
Bohemia		Czech Rep.		140		100		140		FUCO
SONEL (12 plants)		Cameroon		935		56		524		FUCO
Central Dique		Argentina		68		51		35		FUCO
Termoandes		Argentina		643		99		637		FUCO
Paraná—GT		Argentina		845		100		845		FUCO
Ebute		Nigeria		306		95		291		FUCO
Centrogener (7 plants)		Chile		682		99		675		FUCO
Barka		Oman		427		35		149		FUCO
Ras Laffan		Qatar		756		55		416		FUCO
Kelanitissa		Sri Lanka		168		90		151		FUCO
Andres		Dom. Rep.		304		100		304		FUCO

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FOREIGN SUBTOTAL:				30,571				22,360
TOTAL—March 31, 2005				39,560				31,293
Foreign Generation as a Percentage of Total:				77	%			71	%

        IPALCO Generating Plants at March 31, 2005:

Unit		Country		Capacity (MW)		AES Interest (%)		AES Equity (MW)		Regulatory Status
Petersburg		USA		1,730		100		1,730		IURC
H. T. Pritchard (Eagle Valley)		USA		341		100		341		IURC
E. W. Stout		USA		1,102		100		1,102		IURC
Georgetown		USA		79		100		79		IURC
TOTAL—March 31, 2005				3,252				3,252

        Revenues from electric generation capacity—12 months ended March 31, 2005 (millions of dollars):

        IPALCO's electric revenues are allocated between electric generation and electric transmission and distribution activities according to utility rate base. AES generation revenues are derived from the total generation revenues earned by AES subsidiaries times the percentage ownership interest of AES in those subsidiaries.

        There has been no change in the amount of generation capacity owned by IPALCO and a 1,391-MW decrease in the amount of generation capacity owned by AES (excluding IPALCO) from 32,684 MW to 31,293 MW since September 30, 2004. There has been no percentage change in the total revenues earned from the capacity owned by AES and IPALCO in the 12-month period ended March 31, 2005 compared with the 12-month period ended September 30, 2004. The percentage of the total revenues derived from the generation capacity owned by IPALCO has remained 13%.

        The countries in which AES' net generating capacity increased during the fourth quarter of 2004 and the first quarter of 2005 are as follows: Cameroon, Colombia and The Dominican Republic.

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Item (4) per Exemption Order—Electric Transmission and Distribution and Gas Distribution:

        Electric transmission and distribution and gas distribution assets owned as of March 31, 2005 (millions of dollars):

        Electric transmission and distribution and gas distribution revenues for 12 months ending March 31, 2005 (millions of dollars):

        IPALCO's electric revenues are allocated between electric generation and electric transmission and distribution activities according to utility rate base. AES transmission and distribution revenues are derived from the total revenues earned by AES transmission and distribution subsidiaries by multiplying these revenues by the percentage ownership interest of AES in those subsidiaries.

        The total transmission and distribution assets owned by AES and IPALCO have increased since September 30, 2004. IPALCO's transmission and distribution assets have increased and the revenues derived from such assets have increased since September 30, 2004. AES' transmission and distribution assets have increased and the revenues derived from such assets have decreased since September 30, 2004. IPALCO's percentage of the total transmission and distribution assets has remained 24% and IPALCO's percentage of the total revenues from such assets has increased from 9% to 12% for the 12-month period ending March 31, 2005 compared to the 12-month period ending March 31, 2004.

Item (5) per Exemption Order:

        IPL has not sold or transferred any electric and/or gas utility assets to any affiliate company of the AES consolidated holding company system during the fourth quarter of 2004 and the first quarter of 2005.

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Item (6) per Exemption Order:

        During the fourth quarter of 2004 and the first quarter of 2005, no application has been made to or order has been received from the Indiana Utility Regulatory Commission ("IURC") that involves AES' ownership of or oversight over the operations of IPL or IPALCO.

Item (7) per Exemption Order:

        As previously reported, on January 31, 2003, AES announced completion of the sale of CILCORP, including CILCO, to Ameren Corporation after receiving all necessary regulatory approvals.

SIGNATURE

        Pursuant to the requirements of the Public Utility Holding Company Act of 1935, as amended, AES has duly caused this certificate to be signed on its behalf on this 31st day of May, 2005, by the undersigned thereunto duly authorized.

		The AES Corporation
		By:		/s/  VINCENT W. MATHIS       Vincent W. Mathis Assistant General Counsel

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QuickLinks

The AES Corporation SEC Filing Pursuant to Section 3(a)(5) Exemption Order Period Ended March 31, 2005

Item (1) per Exemption Order (statements attached)

CONSOLIDATED STATEMENT OF OPERATIONS (INCLUDES IPALCO) FOR THE TWELVE MONTHS ENDED MARCH 31, 2005 PRO RATA BASIS(1) (Unaudited)
CONSOLIDATED BALANCE SHEET (INCLUDES IPALCO) MARCH 31, 2005 ($ in millions, unaudited)
CONSOLIDATED BALANCE SHEET (INCLUDES IPALCO) MARCH 31, 2005 ($ in millions, unaudited)
IPALCO ENTERPRISES, INC. and SUBSIDIARIES Consolidated Statement of Income ($ In Thousands) (Unaudited)
INDIANAPOLIS POWER & LIGHT COMPANY Statement of Income ($ In Thousands) (Unaudited)
IPALCO ENTERPRISES, INC. and SUBSIDIARIES Consolidated Balance Sheet ($ In Thousands) (Unaudited)
IPALCO ENTERPRISES, INC. and SUBSIDIARIES Consolidated Balance Sheet ($ In Thousands) (Unaudited)
INDIANAPOLIS POWER & LIGHT COMPANY Balance Sheet ($ In Thousands) (Unaudited)
INDIANAPOLIS POWER & LIGHT COMPANY Balance Sheet ($ In Thousands) (Unaudited)

Item (2) per Exemption Order (Income Statement Amounts are 12 months ended)

IPL Contributions To AES/IPALCO Consolidated Holding Company (Pro Rata Consolidation Basis(1)) ($MM)

Item (3) per Exemption Order—Generation Information

Item (4) per Exemption Order—Electric Transmission and Distribution and Gas Distribution
Item (5) per Exemption Order
Item (6) per Exemption Order
Item (7) per Exemption Order

SIGNATURE