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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. 401(k) Profit Sharing Plan and Trust
(the "Plan") and an indeterminate number of interests in the Plan (the
"Plan Interests"). 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
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 and Plan Interests, 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
