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Exhibit 5.1
Shipman & Goodwin LLP One American Row
Counselors at Law Hartford, CT 06103
TEL: (860) 251-5000
September 19, 2000
Board of Directors
ATMI, Inc.
7 Commerce Drive
Danbury, Connecticut 06810
Re: Registration Statement on Form S-3
Ladies and Gentlemen:
We have served as counsel for ATMI, Inc., a Delaware corporation (the
"Company"), in connection with the proposed sale by certain stockholders of a
maximum of 369,505 shares of Common Stock of the Company (the "Shares")
pursuant to a Registration Statement on Form S-3 to be filed with the
Securities and Exchange Commission (the "Registration Statement").
As counsel to the Company, we have examined the Registration Statement,
including the Prospectus contained therein, and such other documents as we have
deemed necessary or appropriate in order to express the opinion set forth
below. In connection with our opinion hereinafter given, we have examined and
relied upon originals, or copies, certified or otherwise, identified to our
satisfaction, of such agreements, documents, certificates and other statements
of government officials, corporate officers and representatives and other
documents as we have deemed relevant and necessary as a basis for such opinion.
In such examination, we have assumed the genuineness of all signatures and the
authenticity of all documents submitted to us as originals and the conformity
with the original documents of documents submitted to us as copies.
Based upon the foregoing, we are of the opinion that the Shares have been
duly authorized and legally issued and are fully paid and non-assessable.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the heading "Legal
Matters" in the Prospectus included in the Registration Statement. In giving
this consent, we do not thereby admit that we come within the category of
persons whose consent is required under Section 7 of the Securities Act or the
rules and regulations of the Securities and Exchange Commission.
Very truly yours,
/s/ Shipman & Goodwin LLP
