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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. 3 )*
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Tetra Technologies Inc.
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(Name of Issuer)
COMMON STOCK
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(Title of Class of Securities)
88162F105
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(CUSIP Number)
Check the following box if a fee is being paid with this statement / /. (A
fee is not required only if the filing person: (1) has a previous statement
on file reporting beneficial ownership of more than five percent of the class
of securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such
class.) (See Rule 13d-7).
*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).
Tax ID # 74-2148293
CIK # 0000844965
This Form 13F is not filed with respect to holdings of affiliated managers,
including Martingale Asset Management, L.P. and other affiliates of
Commerzbank AG, as to which holdings investment discretion is disclaimed.
Page 1 of 5 pages
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CUSIP No. 88162F105 13G Page 2 Of 5
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(1) Name of Reporting Person S.S. or I.R.S. identification nos.
of above person
MONTGOMERY ASSET MANAGEMENT, LLC 94-3273703
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(2) Check the appropriate box if a member of a group (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 (5) Sole voting power
shares 621,500 (as of 8/31/98)
beneficially --------------------------------------------------
owned by (6) Shared voting power
each -0-
reporting --------------------------------------------------
person (7) Sole dispositive power
with 862,300 (as of 8/31/98)
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(8) Shared dispositive power
-0-
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(9) Aggregate amount beneficially owned by each reporting person
862,300 (as of 8/31/98)
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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
6.34% (as of 8/31/98)
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(12) Type of reporting person*
IA
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*See instructions
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Page 3 Of 5
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ITEM 1.
(a) Name of Issuer
Tetra Technologies Inc.
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(b) Address of Issuer's Principal Executive Offices
25025 I-45 North, The Woodlands, TX 77380
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ITEM 2.
(a) Name of Person Filing
MONTGOMERY ASSET MANAGEMENT, LLC
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(b) Address of Principal Business Office
101 CALIFORNIA STREET, SAN FRANCISCO, CA 94111
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(c) Citizenship
DELAWARE LIMITED LIABILITY COMPANY
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(d) Title of Class of Securities
Common Stock
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(e) CUSIP Number
88162F105
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ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULE 13d-1(b) OR 13d-2(b), CHECK
WHETHER THE PERSON FILING IS A:
(a) / / Broker or dealer registered under section 15 of the Act
(b) / / Bank as defined in section 3(a)(6) of the Act
(c) / / Insurance company as defined in section 3(a)(19) of the Act
(d) / / Investment company registered under section 8 of the Investment
Company Act of 1940
(e) /X/ Investment Adviser registered under section 203 of the Investment
Advisers Act of 1940
(f) / / Employee Benefit Plan, Pension Fund which is subject to the
provisions of the Employee Retirement Income Security Act of 1974
or Endowment Fund; see Section 240.13d-1(b)(1)(ii)(F)
(g) / / Parent Holding Company, in accordance with Section
240.13d-1(b)(ii)(G) (Note: See Item 7)
(h) / / Group, in accordance with Section 240.13d-1(b)(1)(ii)(H)
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Page 4 Of 5
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ITEM 4. OWNERSHIP
(a) Amount beneficially owned:
862,300 (as of 8/31/98)
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(b) Percent of class:
6.34% (as of 8/31/98)
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(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote
621,500 (as of 8/31/98)
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(ii) Shared power to vote or to direct the vote
-0-
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(iii) Sole power to dispose or to direct the disposition of
862,300 (as of 8/31/98)
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(iv) Shared power to dispose or to direct the disposition of
-0-
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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 / /
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
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Page 5 Of 5
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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 purposes or effect.
SIGNATURE
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.
9/8/98
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Date
/s/ Dana Schmidt
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Signature
DANA SCHMIDT, CORP. VP & PRINCIPAL
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Name/Title
