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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
INFORMATION STATEMENT PURSUANT TO RULES 13d-1 AND 13d-2
UNDER THE SECURITIES AND EXCHANGE ACT OF 1934
(Amendment No. )*
Tetra Technologies, Inc.
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(Name of Issuer)
Class D Common Stock
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(Title of Class of Securities)
88162F105
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(CUSIP Number)
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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
disclosures provided in a prior cover page.
The information required on 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).
(Continued on following page(s))
Page 1 of 8 Pages
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CUSIP No. 88162F105 13G Page 2 of 8 Pages
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1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
The TCW Group, Inc.
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) / /
(b) /X/
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
Nevada corporation
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NUMBER OF 5 SOLE VOTING POWER
SHARES 760,200
BENEFICIALLY ---------------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH -0-
REPORTING ---------------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH 760,200
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8 SHARED DISPOSITIVE POWER
-0-
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
760,200
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES*
/ /
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
5.9% (see response to Item 4)
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12 TYPE OF REPORTING PERSON*
HC/CO
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP No. 88162F105 13G Page 3 of 8 Pages
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1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Robert Day
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) / /
(b) /X/
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
United States Citizen
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NUMBER OF 5 SOLE VOTING POWER
SHARES 760,200
BENEFICIALLY ---------------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH -0-
REPORTING ---------------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH 760,200
---------------------------------------------
8 SHARED DISPOSITIVE POWER
-0-
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
760,200
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES*
/ /
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
5.9% (see response to Item 4)
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12 TYPE OF REPORTING PERSON*7
HC/IN
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
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Page 4 of 8 Pages
Item 1(a). Name of Issuer:
Tetra Technologies, Inc.
Item 1(b). Address of Issuer's Principal Executive Offices:
25025 I-45 North
The Woodlands, Texas 77380
Northfield, Minnesota 55057
Item 2(a). Name of Persons Filing:
Item 2(b). Address of Principal Business Office:
Item 2(c). Citizenship:
The TCW Group, Inc.
865 South Figueroa Street
Los Angeles, CA 90017
(Nevada Corporation)
Robert Day
200 Park Avenue, Suite 2200
New York, New York 10166
(United States Citizen)
Item 2(d). Title of Class of Securities:
Class D Common Stock
Item 2(e). CUSIP Number:
88162F105
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Page 5 of 8 Pages
Item 3. If this statement is filed pursuant to Rules 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:
Not applicable
(b) [ ] Bank as defined in Section 3(a)(6) of the Act:
Not applicable
(c) [ ] Insurance Company as defined in Section 3(a)(19) of the Act:
Not applicable
(d) [ ] Investment Company registered under Section 8 of the
Investment Company Act:
Not applicable
(e) [ ] Investment Adviser registered under Section 203 of the
Investment Advisers Act of 1940:
Not applicable
(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 13d-1(b)(1)(ii)(F)):
Not applicable
(g) [X] Parent Holding Company, in accordance with Rule
13d-1(b)(ii)(G) (SEE Item 7):
The TCW Group, Inc.
Robert Day (individual who may be deemed to control The
TCW Group, Inc. and other holders of the Class D
Common Stock of the issuer)
(h) [ ] Group, in accordance with Rule 13d-1(b)(1)(ii)(H):
Not applicable.
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Page 6 of 8 Pages
Item 4. Ownership **
THE TCW GROUP, INC.
(a) Amount beneficially owned: 760,200
(b) Percent of class: 5.9%
(c) Number of shares as to which such person has:
(i) Sole power to vote or to direct the vote:
760,200
(ii) Shared power to vote or to direct the vote: none.
(iii) Sole power to dispose or direct the disposition of:
760,200
(iv) Shared power to dispose or to direct the disposition
of: none.
ROBERT DAY
(a) Amount beneficially owned: 760,200
(b) Percent of class: 5.9%
(c) Number of shares as to which such person has:
(i) Sole power to vote or to direct the vote:
760,200
(ii) Shared power to vote or to direct the vote: none.
(iii) Sole power to dispose or direct the disposition of:
760,200
(iv) Shared power to dispose or to direct the disposition
of: none.
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** The filing of this Schedule 13G shall not be construed as an admission
that the reporting person or any of its affiliates is, for the purposes of
Section 13(d) or 13(g) of the Securities Exchange Act of 1934, the beneficial
owner of any securities covered by this Schedule 13G. In addition, the
filing of this Schedule 13G shall not be construed as an admission that the
reporting person or any of its affiliates is the beneficial owner of any
securities covered by this Schedule 13G for any other purposes than Section
13(d) of the Securities Exchange Act of 1934.
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Page 7 of 8 Pages
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.
Various persons other than as described in Item 4 have the
right to receive or the power to direct the receipt of
dividends from, or the proceeds from the sale of, the
Class D Common Stock of Tetra Technologies, Inc.
Item 7. Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on by the Parent Holding
Company.
SEE Exhibit A.
Item 8. Identification and Classification of Members of the Group.
Not applicable. SEE Exhibits A and B.
Item 9. Notice of Dissolution of Group.
Not applicable.
Item 10. Certification.
Because this statement is filed pursuant to Rule 13d-1(b),
the following certification is included:
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.
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Page 8 of 8 Pages
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.
Dated this 12th day of February, 1997.
The TCW Group, Inc.
By: /s/ Mohan V. Phansalkar
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Mohan V. Phansalkar
Authorized Signatory
Robert Day
By: /s/ Mohan V. Phansalkar
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Mohan V. Phansalkar
Under Power of Attorney dated
January 30, 1996, on File with
Schedule 13G Amendment Number 1
for Matrix Service Co. dated
January 30, 1996.
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EXHIBIT A
RELEVANT SUBSIDIARIES OF PARENT HOLDING COMPANY
PART A: TCW ENTITIES
PARENT HOLDING COMPANY:
The TCW Group, Inc.
Robert Day (an individual who may be deemed to control
The TCW Group, Inc.)
RELEVANT SUBSIDIARIES THAT ARE PERSONS DESCRIBED IN RULE 13d-1(b):
(i) Trust Company of the West, a California corporation and
a bank as defined in Section 3(a)(6) of the Securities
Exchange Act of 1934.
(ii) TCW Asset Management Company, a California corporation
and an Investment Adviser registered under Section 203 of
the Investment Advisers Act of 1940.
(iii) TCW Funds Management, Inc., a California corporation
and an Investment Adviser registered under Section 203 of the
Investment Advisers Act of 1940.
Note: No Class D Common Stock of Tetra Technologies,
Inc. is held directly by The TCW Group, Inc.
Other than the indirect holdings of The TCW Group,
Inc. no Class D Common Stock of Tetra
Technologies, Inc. is held directly or indirectly
by Robert Day, an individual who may be deemed to
control The TCW Group, Inc.
PART B: NON TCW ENTITIES
PARENT HOLDING COMPANY:
Robert Day (an individual who may be deemed to control the
holders described below which are not subsidiaries of The TCW
Group, Inc.)
RELEVANT SUBSIDIARIES THAT ARE PERSONS DESCRIBED IN
RULE 13d-1(b):
Oakmont Corporation, a California corporation and an
Investment Adviser registered under Section 203 of the
Investment Advisers Act of 1940.
Cypress International Partners Limited, a British Virgin Islands
corporation and an Investment Adviser registered under
Section 203 of the Investment Advisers Act of 1940.
A-1
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EXHIBIT B
JOINT FILING AGREEMENT
The undersigned acknowledge and agree that the foregoing
statement on Schedule 13G is filed on behalf of each of the undersigned and
that all subsequent amendments to this statement on Schedule 13G shall be
filed on behalf of each of the undersigned without the necessity of filing
additional joint acquisition statements. The undersigned acknowledge that
each shall be responsible for the timely filing of such amendments, and for
the completeness and accuracy of the information concerning him or it
contained therein, but shall not be responsible for the completeness and
accuracy of the information concerning the other, except to the extent that
he or it knows or has reason to believe that such information is accurate.
Dated: February 12, 1997
The TCW Group, Inc.
By: /s/ Mohan V. Phansalkar
-----------------------
Mohan V. Phansalkar
Authorized Signatory
Robert Day
By: /s/ Mohan V. Phansalkar
-----------------------
Mohan V. Phansalkar
Under Power of Attorney dated
January 30, 1996, on File with
Schedule 13G Amendment Number 1 for
Matrix Service Co. dated January
30, 1996.
B-1
