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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
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Schedule 13G
(Rule 13d-102)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES
13d-1(b),(c) and (d) AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2(b)
ATMI, Inc.
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(Name of Issuer)
Common Stock, par value $0.01 per share
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(Title of Class of Securities)
00 207R 10 1
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(CUSIP Number)
MARCH 31, 1998 AND APRIL 2, 1998
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(DATES OF EVENTS WHICH REQUIRE FILING OF THIS STATEMENT)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:
[ ] Rule 13d-1(b)
[ X ] Rule 13d-1(c)
[ ] Rule 13d-1(d)
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CUSIP No. 00 207R 10 1 13G Page 2 of 6 Pages
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1 NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
STEPHEN H. SIEGELE
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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
USA
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5 SOLE VOTING POWER
NUMBER 2,541,305
OF ----------------------------------------------
SHARES 6 SHARED VOTING POWER
BENEFICIALLY 0
OWNED BY ----------------------------------------------
REPORTING 7 SOLE DISPOSITIVE POWER
PERSON 2,541,305
WITH ----------------------------------------------
8 SHARED DISPOSITIVE POWER
0
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,541,305
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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
12.4%
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12 TYPE OF REPORTING PERSON*
IN
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
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Page 3 of 6 Pages
ITEM 1(A) NAME OF ISSUER:
ATMI, Inc.
ITEM 1(B) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
7 Commerce Drive
Danbury, Connecticut 06810-4169
ITEM 2(A) NAME OF PERSON FILING:
Stephen H. Siegele
ITEM 2(B) ADDRESS OF PRINCIPAL BUSINESS OFFICE:
6805 Capital of Texas Highway
Suite 330
Austin, Texas 78731
ITEM 2(C) CITIZENSHIP:
U.S.A.
ITEM 2(D) TITLE OF CLASS OF SECURITIES:
Common Stock, par value $0.01 per share
ITEM 2(E) CUSIP NUMBER:
00 207R 10 1
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULES
13D-1(B) OR 13D-2(B) OR (C), CHECK WHETHER THE PERSON
FILING IS A:
(a) [ ] Broker or dealer registered under Section
15 of the Exchange Act.
(b) [ ] Bank as defined in Section 3(a)(6) of the
Exchange Act.
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Page 4 of 6 Pages
(c) [ ] Insurance company as defined in Section 3(a)(19)
of the Exchange Act.
(d) [ ] Investment company registered under Section 8
of the Investment Company Act.
(e) [ ] An investment adviser in accordance with Rule
13d-1(b)(1)(ii)(E);
(f) [ ] An employee benefit plan or endowment fund in
accordance with Rule 13d-1(b)(1)(ii)(F);
(g) [ ] A parent holding company or control person in
accordance with Rule 13d-1(b)(1)(ii)(G);
(h) [ ] A savings association as defined in Section
3(b) of the Federal Deposit Insurance Act;
(i) [ ] A church plan that is excluded from the
definition of an investment company under
Section 3(c)(14) of the Investment Company
Act;
(j) [ ] Group, in accordance with Rule 13d-1(b)(1)
(ii)(J).
If this statement is filed pursuant to Rule 13d-1(c),
check this box [X].
ITEM 4. OWNERSHIP.
(a) Amount Beneficially Owned: 2,541,305
(b) Percent of Class: 12.4% (based on 20,437,992 shares
outstanding)
(c) Number of shares as to which such person has:
(i) Sole power to vote or to direct the vote:
2,541,305
(ii) Shared power to vote or to direct the vote: 0
(iii) Sole power to dispose or to direct the
disposition of: 2,541,305
(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.
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Page 5 of 6 Pages
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.
ITEM 10. CERTIFICATION.
By signing below I certify that, to the best of my
knowledge and belief, the securities referred to above
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.
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Page 6 of 6 Pages
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief,
the undersigned certifies that the information set forth in this statement is
true, complete and correct.
April 2, 1998
/s/ STEPHEN H. SIEGELE
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Stephen H. Siegele
