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OMB APPROVAL
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. __________)*
TESORO PETROLEUM CORPORATION
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(Name of Issuer)
COMMON STOCK
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(Title of Class of Securities)
881609101
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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 8 pages
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CUSIP NO. 881609101 13G PAGE 2 OF 8 PAGES
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NAME OF REPORTING PERSON
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Wanger Asset Management, L.P. 36-3820584
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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
Delaware
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SOLE VOTING POWER
5
NUMBER OF None
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
1,721,000
OWNED BY
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING None
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
1,721,000
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
1,721,000
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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
6.52%
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TYPE OF REPORTING PERSON*
12
IA
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*SEE INSTRUCTION BEFORE FILLING OUT!
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CUSIP NO. 881609101 13G PAGE 3 OF 8 PAGES
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NAME OF REPORTING PERSON
1 S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Wanger Asset Management, Ltd.
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CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [_]
Not Applicable (b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
Delaware
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SOLE VOTING POWER
5
NUMBER OF None
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
1,721,000
OWNED BY
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING None
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
1,721,000
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
1,721,000
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
Not Applicable
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11
6.52%
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TYPE OF REPORTING PERSON*
12
CO
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*SEE INSTRUCTION BEFORE FILLING OUT!
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CUSIP NO. 881609101 13G PAGE 4 OF 8 PAGES
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NAME OF REPORTING PERSON
1 S.S. or IDENTIFICATION NO. OF ABOVE PERSON
Ralph Wanger
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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
U.S.A.
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SOLE VOTING POWER
5
NUMBER OF None
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
1,721,000
OWNED BY
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING None
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
1,721,000
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
1,721,000
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
Not Applicable
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11
6.52%
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TYPE OF REPORTING PERSON*
12
IN
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*SEE INSTRUCTION BEFORE FILLING OUT!
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Item 1(a) Name of Issuer:
Tesoro Petroleum Corporation
Item 1(b) Address of Issuer's Principal Executive Offices:
8700 Tesoro Drive
San Antonio, Texas 78217-6218
Item 2(a) Name of Person Filing:
Wanger Asset Management, L.P. ("WAM");
Wanger Asset Management Ltd., the general partner of WAM
("WAM LTD.");
Ralph Wanger ("Wanger")
Item 2(b) Address of Principal Business Office:
WAM, WAM LTD. and Wanger are all located at:
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606
Item 2(c) Citizenship:
WAM is a Delaware limited partnership.
WAM LTD. is a Delaware corporation.
Wanger is a U.S. citizen.
Item 2(d) Title of Class of Securities:
Common Stock
Item 2(e) CUSIP Number:
881609101
Item 3 Type of Person:
(e) WAM is an Investment Adviser registered under section
203 of the Investment Advisers Act of 1940; WAM LTD. is the
General Partner of the Investment Adviser; Wanger is the
principal stockholder of the General Partner.
Page 5 of 8 pages
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Item 4 Ownership (at December 31, 1996):
--
(a) Amount owned "beneficially" within the meaning of
rule 13d-3:
1,721,000 shares
(b) Percent of class:
6.52% (based on 26,409,961 shares outstanding on
October 31, 1996)
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote:
none
(ii) shared power to vote or to direct the vote:
1,721,000
(iii) sole power to dispose or to direct the
disposition of: none
(iv) shared power to dispose or to direct
disposition of: 1,721,000
WAM serves as investment adviser to Acorn Investment
Trust, Series Designated Acorn Fund (the "Trust").
Various of WAM's limited partners and employees are
also officers and trustees of the Trust, but WAM does
not consider the Trust to be controlled by such
persons. Although the Trust is not controlled by WAM,
pursuant to rule 13d-3(a) the 900,000 shares
beneficially owned by the Trust, with respect to which
the Trust has delegated to WAM shared voting power and
shared dispositive power, are considered to be shares
beneficially owned by WAM by reason of such delegated
powers. In addition to the shares beneficially owned by
the Trust, other clients of WAM may own shares which
are not included in the aggregate number of shares
reported herein because WAM does not have or share
voting or investment power over those shares.
Item 5 Ownership of Five Percent or Less of a Class:
Not Applicable
Item 6 Ownership of More than Five Percent on Behalf of Another Person:
The shares reported herein have been acquired on behalf of
discretionary clients of WAM. Persons other than WAM are
entitled to receive all dividends from, and proceeds from
the sale of, those shares.
Page 6 of 8 pages
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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 7 of 8 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 14, 1997
The undersigned corporation, on the date above written, agrees
and consents to the joint filing on its behalf of this Schedule
13G in connection with its beneficial ownership of the security
reported herein.
WANGER ASSET MANAGEMENT, LTD.
for itself and as general partner of
WANGER ASSET MANAGEMENT, L.P.
By: /s/ Bruce H. Lauer
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Bruce H. Lauer
Vice President
The undersigned individual, on the date above written, agrees and
consents to the joint filing on his behalf of this Schedule 13G
in connection with his beneficial ownership of the security
reported herein.
RALPH WANGER
/s/ Ralph Wanger
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Page 8 of 8 pages
