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[letterhead of Thompson Coburn LLP]
July 21, 2000
Allegiant Bancorp, Inc.
2122 Kratky Road
St. Louis, Missouri 63114
Re: Form S-8 - 600,000 Shares of Allegiant Bancorp, Inc. Common Stock,
$0.01 Par Value
Ladies and Gentlemen:
We refer you to the Registration Statement on Form S-8 filed by
Allegiant Bancorp, Inc. (the "Company") on July 21, 2000 (the
"Registration Statement") with the Securities and Exchange Commission
(the "SEC") under the Securities Act of 1933, as amended, pertaining to
the proposed issuance by the Company of up to 600,000 shares of the
Company's common stock, $0.01 par value (the "Shares"), to participants
under the Allegiant Bancorp, Inc. 2000 Stock Incentive Plan (the
"Plan"). In rendering the opinions set forth herein, we have examined
such corporate records of the Company, such laws and such other
information as we have deemed relevant, including the Company's Articles
of Incorporation, as amended, and Bylaws, as amended and currently in
effect, the resolutions adopted by the Company's Board of Directors and
shareholders relating to the Plan, certificates received from state
officials and statements we have received from officers and
representatives of the Company. In delivering this opinion, we have
assumed: the genuineness of all signatures; the authenticity of all
documents submitted to us as originals; the conformity to the originals
of all documents submitted to us as certified, photostatic or conformed
copies; the authenticity of the originals of all such latter documents;
and the correctness of statements submitted to us by officers and
representatives of the Company.
Based only on the foregoing, we are of the opinion that:
1. The Company has been duly incorporated and is validly existing
under the laws of the State of Missouri; and
2. The Shares, when issued by the Company in accordance with the
Plan, will be validly issued, fully paid and nonassessable.
We consent to the filing of this opinion as an exhibit to the
Registration Statement.
Very truly yours,
/s/ Thompson Coburn LLP
