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EXHIBIT 5.1
August 2, 2000
CoStar Group, Inc.
2 Bethesda Metro Center
Bethesda, MD 20814
Ladies and Gentlemen:
We have acted as special counsel for CoStar Group, Inc., a Delaware
corporation (the "Company"), in connection with the Company's registration
statement on Form S-3 (the "Registration Statement"). The Registration
Statement covers 1,123,855 shares of common stock, $0.01 par value, of the
Company (the "Shares"), to be offered and sold by certain stockholders of the
Company.
With your permission, all assumptions and statements of reliance herein
have been made without any independent investigation or verification on our
part except to the extent otherwise expressly stated, and we express no opinion
with respect to the subject matter or accuracy of such assumptions or items
relied upon.
In connection with this opinion, we have (i) investigated such questions
of law, (ii) examined originals or certified, conformed or reproduction copies
of such agreements, instruments, documents and records of the Company, such
certificates of public officials and such other documents, and (iii) received
such information from officers and representatives of the Company as we have
deemed necessary or appropriate for the purposes of this opinion. In all
examinations, we have assumed the legal capacity of all natural persons
executing documents, the genuineness of all signatures, the authenticity of
original and certified documents and the conformity to original or certified
copies of all copies submitted to us as conformed or reproduction copies. As to
various questions of fact relevant to the opinions expressed herein, we have
relied upon, and assume the accuracy of, representations and warranties
contained in the documents and certificates and oral or written statements and
other information of or from representatives of the Company and others and
assume compliance on the part of all parties to the documents with their
covenants and agreements contained therein.
Based upon the foregoing and subject to the limitations, qualifications
and assumptions set forth herein, we are of the opinion that the Shares are
validly issued, fully paid and non-assessable.
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The opinion expressed herein is limited to the General Corporation Law of
the State of Delaware, the Delaware Constitution and reported judicial
decisions interpreting those laws, each as currently in effect.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to this firm under the caption
"Legal Matters" in the Registration Statement. In giving such consent, we do not
hereby admit that we are in the category of such persons whose consent is
required under Section 7 of the Securities Act of 1933.
Very truly yours,
FRIED, FRANK, HARRIS, SHRIVER & JACOBSON
By: /s/ Andrew P. Varney
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Andrew P. Varney
