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[LETTERHEAD OF GRAY CARY WARE & FREIDENRICH LLP]
EXHIBIT 5.1
May 30, 2000
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549
Ladies and Gentlemen:
As legal counsel for NetRatings, Inc., a Delaware corporation (the "Company"),
we are rendering this opinion in connection with the registration under the
Securities Act of 1933, as amended, of up to 4,971,175 shares of the Common
Stock, $0.001 par value, of the Company which may be issued pursuant to the
exercise of options and purchase rights granted under the Company's 1998 Stock
Plan and its 1999 Employee Stock Purchase Plan (collectively, the "Plans").
We have examined all instruments, documents and records which we deemed relevant
and necessary for the basis of our opinion hereinafter expressed. In such
examination, we have assumed the genuineness of all signatures and the
authenticity of all documents submitted to us as originals and the conformity to
the originals of all documents submitted to us as copies. We are admitted to
practice only in the State of California and we express no opinion concerning
any law other than the law of the State of California, the corporation laws of
the State of Delaware and the federal law of the United States. As to matters of
Delaware corporation law, we have based our opinion solely upon our examination
of such laws and the rules and regulations of the authorities administering such
laws, all as reported in standard, unofficial compilations. We have not obtained
opinions of counsel licensed to practice in jurisdictions other than the State
of California.
Based on such examination, we are of the opinion that the 4,971,175 shares of
Common Stock which may be issued under the Plans are duly authorized shares of
the Company's Common Stock, and, when issued against receipt of the
consideration therefor in accordance with the provisions of the Plans, will be
validly issued, fully paid and nonassessable. We hereby consent to the filing of
this opinion as an exhibit to the Registration Statement referred to above and
the use of our name wherever it appears in said Registration Statement.
Respectfully submitted,
GRAY CARY WARE & FREIDENRICH LLP
