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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
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SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 1)*
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Tetra Tech, Inc.
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(Name of Issuer)
Common Stock
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(Title of Class of Securities)
88162G103
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(CUSIP Number)
December 31, 2003
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(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
[X] Rule 13d-1(b)
[_] Rule 13d-1(c)
[_] Rule 13d-1(d)
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*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).
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Page 1 of 9 pages
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CUSIP No. 88162G103 13G Page 2 of 9 Pages
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1 NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Columbia Wanger Asset Management, L.P. 36-3820584
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
Not Applicable (a) [_]
(b) [_]
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
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5 SOLE VOTING POWER
NUMBER OF SHARES
None
BENEFICIALLY
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OWNED BY 6 SHARED VOTING POWER
EACH 2,711,000
REPORTING -----------------------------------------------------------
7 SOLE DISPOSITIVE POWER
PERSON WITH
None
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8 SHARED DISPOSITIVE POWER
2,711,000
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,711,000
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
Not Applicable [_]
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.987%
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12 TYPE OF REPORTING PERSON
IA
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CUSIP No. 88162G103 13G Page 3 of 9 Pages
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1 NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
WAM Acquisition GP, Inc.
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
Not Applicable (a) [_]
(b) [_]
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
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NUMBER OF SHARES 5 SOLE VOTING POWER
BENEFICIALLY None
OWNED BY ----------------------------------------------------------
6 SHARED VOTING POWER
EACH
2,711,000
REPORTING
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PERSON WITH 7 SOLE DISPOSITIVE POWER
None
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8 SHARED DISPOSITIVE POWER
2,711,000
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,711,000
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
Not Applicable [_]
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.987%
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12 TYPE OF REPORTING PERSON
CO
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Item 1(a) Name of Issuer:
Tetra Tech, Inc.
Item 1(b) Address of Issuer's Principal Executive Offices:
3475 East Foothill Boulevard
Pasadena, California 91107
Item 2(a) Name of Person Filing:
Columbia Wanger Asset Management, L.P. ("WAM")
WAM Acquisition GP, Inc., the general partner of WAM ("WAM GP")
Item 2(b) Address of Principal Business Office:
WAM and WAM GP are both located at:
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606
Item 2(c) Citizenship:
WAM is a Delaware limited partnership; and WAM GP is a
Delaware corporation
Item 2(d) Title of Class of Securities:
Common Stock
Item 2(e) CUSIP Number:
88162G103
Item 3 Type of Person:
(e) WAM is an Investment Adviser registered under section
203 of the Investment Advisers Act of 1940; WAM GP is
the General Partner of the Investment Adviser.
Page 4 of 9 pages
Item 4 Ownership (at December 31, 2003):
(a) Amount owned "beneficially" within the meaning of rule
13d-3:
2,711,000
(b) Percent of class:
4.987% (based on 54,365,956 shares outstanding as of
December 8, 2003).
(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:
2,711,000
(iii) sole power to dispose or to direct the
disposition of: none
(iv) shared power to dispose or to direct
disposition of: 2,711,000
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
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
Page 5 of 9 Pages
Item 10 Certification:
By signing below I certify that, to the best of my knowledge
and belief, the securities referred to above were acquired and are
held in the ordinary course of business and were not acquired and are
not held for the purpose of or with the effect of changing or
influencing the control of the issuer of the securities and were not
acquired and are not held in connection with or as a participant in
any transaction having that purpose or effect.
Page 6 of 9 Pages
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 10, 2004
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.
WAM Acquisition GP, Inc.
for itself and as general partner of
COLUMBIA WANGER ASSET MANAGEMENT, L.P.
By: /s/ Bruce H. Lauer
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Bruce H. Lauer
Senior Vice President and
Secretary
Page 7 of 9 Pages
Exhibit Index
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Exhibit 1 Joint Filing Agreement dated as of February 10, 2004 by and
among Columbia Wanger Asset Management, L.P. and WAM
Acquisition GP, Inc.
Page 8 of 9 Pages
EXHIBIT 1
JOINT FILING AGREEMENT
The undersigned hereby agree to the joint filing of the Schedule 13G to
which this Agreement is attached.
Dated: February 10, 2004
WAM Acquisition GP, Inc.
for itself and as general partner of
COLUMBIA WANGER ASSET MANAGEMENT, L.P.
By: /s/ Bruce H. Lauer
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Bruce H. Lauer
Senior Vice President and
Secretary
Page 9 of 9 pages