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[LATHAM & WATKINS LETTERHEAD]
October 12, 2000
USinternetworking, Inc.
One USi Plaza
Annapolis, Maryland 21401
Re: Registration Statement on Form S-3
Ladies and Gentlemen:
In connection with the registration by USinternetworking, Inc., a
Delaware corporation (the "Company"), of an aggregate maximum offering of
$150,000,000 of shares of common stock of the Company (the "Shares"), under the
Securities Act of 1933, as amended, by the Company on Form S-3 filed with the
Securities and Exchange Commission (the "Commission") on October 12, 2000 (the
"Registration Statement"), you have requested our opinion with respect to the
matters set forth below.
In our capacity as your counsel in connection with such registration,
we are familiar with the proceedings taken and proposed to be taken by the
Company in connection with the authorization, issuance and sale of the Shares,
and for purposes of this opinion, have assumed such proceedings will be timely
completed in the manner presently proposed. In addition, we have made such legal
and factual examinations and inquiries, including an examination of originals or
copies certified or otherwise identified to our satisfaction of such documents,
corporate records and instruments, as we have deemed necessary or appropriate
for purposes of this opinion.
In our examination, we have assumed the genuineness of all signatures,
the authenticity of all documents submitted to us as originals, and the
conformity to authentic original documents of all documents submitted to us as
copies.
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LATHAM & WATKINS
October 12, 2000
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We are opining herein as to the effect on the subject transaction only
of the General Corporation Law of the State of Delaware, and we express no
opinion with respect to the applicability thereto, or the effect thereon, of any
other laws, or as to any matters of municipal law or the laws of any local
agencies within any state.
Subject to the foregoing, it is our opinion that the Shares have been
duly authorized, and, upon issuance, delivery and payment therefor in the manner
contemplated by the Registration Statement, will be validly issued, fully paid
and nonassessable.
We consent to your filing this opinion as an exhibit to the
Registration Statement and to the reference to our firm contained under the
heading "Legal Matters."
Very truly yours,
/s/ Latham & Watkins
