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[LETTERHEAD]
June 30, 2000
DoubleClick Inc.
450 West 33rd Street
New York, NY 10001
Ladies and Gentlemen:
We have assisted in the preparation and filing by DoubleClick
Inc., a Delaware corporation (the "Company"), of a Registration Statement on
Form S-3 (the "Registration Statement"), with the Securities and Exchange
Commission, relating to the sale by certain selling stockholders (the "Selling
Stockholders") of up to 188,768 shares (the "Shares") of the Company's common
stock, par value $.001 per share.
We have examined such records and documents and have made such
examination of laws as we considered necessary to form a basis for the opinion
set forth herein. In our examination, we have assumed the genuineness of all
signatures, the authenticity of all documents submitted to us as originals, and
the conformity with the originals of all documents submitted to us as copies
thereof. Based upon and subject to the foregoing, we are of the opinion that the
Shares are legally issued, fully paid and nonassessable.
We consent to the filing of this opinion letter as Exhibit 5
to the Registration Statement and to the reference to this firm under the
caption "Legal Matters" in the prospectus which is part of the Registration
Statement. In giving this consent, we do not thereby admit that we are within
the category of persons whose consent is required under Section 7 of the Act,
the rules and regulations of the Securities and Exchange Commission promulgated
thereunder, or Item 509 of Regulation S-K.
This opinion letter is rendered as of the date first written
above and we disclaim any obligation to advise you of facts, circumstances,
events or developments which hereafter may be brought to our attention and which
may alter, affect or modify the opinion expressed herein. Our opinion is
expressly limited to the matters set forth above and we render no opinion,
whether by implication or otherwise, as to any other matters relating to the
Company, the Selling Stockholder or the Shares.
Very truly yours,
/s/ BROBECK, PHLEGER & HARRISON LLP
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BROBECK, PHLEGER & HARRISON LLP
