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[Letterhead of Brobeck, Phleger & Harrison LLP]
November 2, 2000
DoubleClick Inc.
450 West 33rd Street
New York, New York 10001
Re: DoubleClick Inc. Registration Statement on
Form S-4 for 6,520,230 Shares of Common Stock
Ladies and Gentlemen:
We have acted as counsel to DoubleClick Inc., a Delaware corporation (the
'Company'), in connection with the registration by the Company of 6,520,230
shares of the Company's common stock (collectively, 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 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 and such other instruments, documents or other information as we deemed
necessary or appropriate in rendering our opinion. 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.
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
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BROBECK, PHLEGER & HARRISON LLP
