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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G/A
Under the Securities Exchange Act of 1934
(Amendment No. 1)*
AES CORPORATION
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(Name of Issuer)
COMMON STOCK, CLASS A
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(Title of Class of Securities)
00130H105
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(CUSIP Number)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
Page 1 of 5 pages
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CUSIP NO. 05010310 13G PAGE 2 OF 5 PAGES
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NAME OF REPORTING PERSON
1 S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Acorn Investment Trust, Series Designated Acorn Fund 36-2962100
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CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [_]
Not Applicable (b) [_]
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SEC USE ONLY
3
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CITIZENSHIP OR PLACE OF ORGANIZATION
4
Massachusetts
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SOLE VOTING POWER
5
NUMBER OF
None
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
2,230,000
OWNED BY
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EACH SOLE DISPOSITIVE POWER
7
REPORTING None
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
2,230,000
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
2,230,000
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CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
Not Applicable
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PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
1.28%
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TYPE OF REPORTING PERSON*
12
IV
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*SEE INSTRUCTION BEFORE FILLING OUT!
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Item 1(a) Name of Issuer:
Aes Corporation
Item 1(b) Address of Issuer's Principal Executive Offices:
1001 North 19th Street
Arlington, VA 22209
Item 2(a) Name of Person Filing:
Acorn Investment Trust, Series Designated Acorn Fund
Item 2(b) Address of Principal Business Office:
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606
Item 2(c) Citizenship:
The filing person is a Massachusetts business trust.
Item 2(d) Title of Class of Securities:
Common Stock Class A
Item 2(e) CUSIP Number:
Item 3 Type of Person:
(d) Investment company registered under section 8 of the
Investment Company Act
Item 4 Ownership (at December 31, 1997):
(a) Amount owned "beneficially" within the meaning of rule
13d-3:
2,230,000 shares
(b) Percent of class:
1.28%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote: none
Page 3 of 5 pages
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(ii) shared power to vote or to direct the vote:
2,230,000
(iii) sole power to dispose or to direct the
disposition of: none
(iv) shared power to dispose or to direct
disposition of: 2,230,000
Power over voting and disposition of the securities is
shared with Wanger Asset Management, L.P. which is the
investment advisor of Acorn Investment Trust, Series
Designated Acorn Fund.
Item 5 Ownership of Five Percent or Less of a Class:
If this statement is being filed to report the fact that as
of the date hereof the reporting person has ceased to be the
beneficial owner of more than five percent of the class of
equity securities, check the following (X).
Item 6 Ownership of More than Five Percent on Behalf of Another Person:
Not Applicable
Item 7 Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on by the Parent Holding
Company:
Not Applicable
Item 8 Identification and Classification of Members of the Group:
Not Applicable
Item 9 Notice of Dissolution of Group:
Not Applicable
Item 10 Certification:
By signing below I certify that, to the best of my knowledge
and belief, the securities referred to above were acquired in the
ordinary course of business and were not acquired for the purpose
of and do not have the effect of changing or influencing the
control of the issuer of such securities and were not acquired in
connection with or as a participant in any transaction having
such purpose or effect.
Page 4 of 5 pages
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Signature
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After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.
Date: February 11, 1998
ACORN INVESTMENT TRUST, SERIES
DESIGNATED ACORN FUND
By: /s/ Bruce H. Lauer
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Bruce H. Lauer
Vice President
Page 5 of 5 pages
