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Exhibit 5.1
June 12, 2000
Concentric Network Corporation
1400 Parkmoor Avenue
San Jose, CA 95126
Re: Registration Statement on Form S-8
Gentlemen:
We have examined the Registration Statement on Form S-8 to be filed by you
with the Securities and Exchange Commission on or about June 12, 2000 (the
"Registration Statement") in connection with the registration under the
Securities Act of 1933, as amended; Common Stock shares reserved for the 1997
Stock Plan, an additional 800,000 Common Stock shares reserved for the 1997
Employee Stock Purchase Plan 1,000,000 Common Stock shares reserved for issuance
under The Concentric Networks United Kingdom Limited Share Option Scheme and
500,000 Common Stock shares reserved for issuance under The Concentric Network
Corporation Netherlands Stock Option Scheme (collectively referred to as the
"Plans"). As your legal counsel, we have examined the proceedings taken and are
familiar with the proceedings proposed to be taken by you in connection with the
sale and issuance of such Common Stock under the Plans.
It is our opinion that, when issued and sold in the respective manners
referred to in the Plans, and pursuant to the agreements which accompany the
Plans, the Common Stock issued and sold thereby will be legally and validly
issued, fully paid and non-assessable.
We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to the use of our name wherever appearing in the
Registration Statement, including any amendments thereto.
Very truly yours,
WILSON SONSINI GOODRICH & ROSATI
Professional Corporation
/s/ Wilson Sonsini Goodrich & Rosati
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Wilson Sonsini Goodrich & Rosati
