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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
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SCHEDULE 13G
INFORMATION STATEMENT PURSUANT TO RULES 13d-1 AND 13d-2
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. )
THERMATRIX INC.
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(NAME OF ISSUER)
COMMON STOCK
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(TITLE OF CLASS OF SECURITIES)
00088 355 01
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(CUSIP NUMBER)
(CONTINUED ON FOLLOWING PAGE(S))
(PAGE 1 OF 5 PAGES)
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CUSIP NO. 00088 355 01 13G PAGE 2 OF 5 PAGES
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1 NAME OF REPORTING PERSONS
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS
PRENTIS COBB HALE FAMILY TRUST DATED 7/13/93
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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
California
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5 SOLE VOTING POWER
NUMBER 422,529 SHARES OF COMMON STOCK
OF ----------------------------------------------------
SHARES 6 SHARED VOTING POWER
BENEFICIALLY -0-
OWNED BY ----------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING 422,529 SHARES OF COMMON STOCK
PERSON ----------------------------------------------------
WITH 8 SHARED DISPOSITIVE POWER
-0-
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
422,529 SHARES OF COMMON STOCK
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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
5.7% AS OF DECEMBER 31, 1996
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12 TYPE OF REPORTING PERSON*
OO
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP NO. 00088 355 01 13G PAGE 3 OF 5 PAGES
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ITEM 1(A) NAME OF ISSUER:
Thermatrix Inc.
ITEM 1(B) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
101 Metro Drive, Suite 248
San Jose, CA 95110
ITEM 2(A) NAME OF PERSON FILING:
Prentis Cobb Hale Family Trust dated 7/13/93
ITEM 2(B) ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:
945 Green Street, Apt. No. 6
San Francisco, CA 94133
ITEM 2(C) CITIZENSHIP:
United States
ITEM 2(D) TITLE OF CLASS OF SECURITIES:
Common Stock
ITEM 2(E) CUSIP NUMBER:
00088 355 01
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULE
13d-1(b) OR 13d-2(b), CHECK WHETHER THE PERSON FILING
IS A:
Not Applicable.
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CUSIP NO. 00088 355 01 13G PAGE 4 OF 5 PAGES
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ITEM 4. OWNERSHIP.
(a) Amount Beneficially Owned: 422,529
(b) Percent of Class: 5.7% as of December 31, 1996
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote: 422,529
(ii) shared power to vote or to direct the vote: -0-
(iii) sole power to dispose or to direct the disposition of:
422,529
(iv) shared power to dispose or to direct the disposition
of: -0-
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.
Thomas M. Peterson, George T. Cronin and Denise Hale, Co-Trustees
of Prentis Cobb Hale Family Trust dated 7/13/93
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.
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CUSIP NO. 00088 355 01 13G PAGE 5 OF 5 PAGES
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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.
Date: February 13, 1997
/s/ Thomas M. Peterson
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Thomas M. Peterson,
Co-Trustee, Prentis Cobb Hale Family Trust dated
7/13/93
