EXHIBIT 5.1
[LETTERHEAD]
October 16, 2000
Micromuse Inc.
139 Townsend Street
San Francisco, California 94107
Ladies and Gentlemen:
We have assisted in the preparation and filing by Micromuse 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 142,850 shares (the "Shares") of the Company's common stock, par value $.01
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 of the Shares.
Very truly yours,
/s/ BROBECK, PHLEGER & HARRISON LLP
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BROBECK, PHLEGER & HARRISON LLP
