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[letterhead of Thompson Coburn LLP]
July 24, 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 24, 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
