Exhibit 5.1
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MORRISON & FOERSTER LLP
2000 Pennsylvania Avenue, Suite 5500
Washington, D.C. 20006-1888
202-887-1500 * FAX 202-887-0764
November 22, 1999
CAIS Internet, Inc.
1255 22/nd/ Street, N.W.
Washington, D.C. 20037
Re: CAIS Internet, Inc. Amended and Restated 1998 Equity Incentive Plan
(the "CAIS Plan") and Atcom, Inc. 1996 Stock Option/Stock Issuance
Plan (the "Atcom Plan")
Ladies and Gentlemen:
At your request, we have examined the Registration Statement on Form S-8
executed by you on November 22, 1999, and to be filed with the Securities and
Exchange Commission in connection with the registration under the Securities Act
of 1933, as amended (the "Securities Act"), of an aggregate of 3,500,000 shares
of your common stock, $.01 par value (the "Common Stock"), which will be
issuable under the CAIS Plan and the Atcom Plan.
As your counsel in connection with the Registration Statement, we have examined
the proceedings taken by you in connection with the adoption of the CAIS Plan
and the assumption of the Atcom Plan by CAIS Internet, Inc., and such documents
as we have deemed necessary to render this opinion, in connection therewith.
Based upon the foregoing, it is our opinion that the Common Stock, when issued
and outstanding pursuant to the terms of the CAIS Plan and the Atcom Plan, will
be validly issued, fully paid and non-assessable.
We hereby consent to the filing of this opinion with the Commission as an
exhibit to the Registration Statement in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act. In giving such
consent, we do not hereby admit that we are in the category of persons whose
consent is required under Section 7 of the Securities Act or the rules and
regulations of the Commission.
Very truly yours,
/s/ Morrison & Foerster LLP