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November 28, 2000
DoubleClick Inc.
450 West 33rd Street
New York, New York 10001
Re: DoubleClick Inc. Registration Statement on Form S-4
for 5,667,684 Shares of Common Stock
Ladies and Gentlemen:
We have acted as counsel to DoubleClick Inc., a Delaware corporation
(the "Company"), in connection with the proposed issuance and sale by the
Company of up to 5,667,684 shares of the Company's Common Stock (the "Shares")
pursuant to the Company's Registration Statement on Form S-4 (the "Registration
Statement") filed with the Securities and Exchange Commission under the
Securities Act of 1933, as amended (the "Act").
This opinion is being furnished in accordance with the requirements of
Item 21(a) of Form S-4 and Item 601(b)(5)(i) of Regulation S-K.
We have reviewed the Company's charter documents and the corporate
proceedings taken by the Company in connection with the issuance and sale of the
Shares. Based on such review, we are of the opinion that the Shares have been
duly authorized, and if, as and when issued in accordance with the Registration
Statement and the related proxy statement/prospectus (as amended and
supplemented through the date of issuance) will be legally issued, fully paid
and nonassessable.
We consent to the filing of this opinion letter as Exhibit 5.1 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.
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DoubleClick Inc.
Page 2
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 or the
Shares.
Very truly yours,
/s/ Brobeck, Phleger & Harrison LLP
BROBECK, PHLEGER & HARRISON LLP
