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[WILSON SONSINI GOODRICH & ROSATI LETTERHEAD]
EXHIBIT 8.1
August 16, 2000
Komag, Incorporated
1710 Automation Parkway
San Jose, CA 95131
Ladies and Gentlemen:
We have acted as counsel to Komag, Incorporated, a Delaware Corporation
("Komag"), in connection with the proposed merger (the "Merger") among Komag,
KHM, Inc., a Delaware corporation and a wholly-owned subsidiary of Komag
("Merger Sub"), and HMT Technology Corporation, a Delaware corporation ("HMT"),
pursuant to the Agreement and Plan of Reorganization dated as of April 26, 2000
(the "Agreement"). The Merger and certain proposed transactions incident thereto
are described in the Registration Statement on Form S-4 (the "Registration
Statement") of Komag which includes the Proxy Statement/Prospectus of HMT and
Komag (the "Proxy Statement/Prospectus"). This opinion is being rendered
pursuant to the requirements of Item 21(a) of Form S-4 under the Securities Act
of 1933, as amended. Unless otherwise indicated, any capitalized terms used
herein and not otherwise defined have the meaning ascribed to them in the Proxy
Statement/Prospectus.
In connection with this opinion, we have examined and are familiar with
the Agreement, the Registration Statement, and such other presently existing
documents, records and matters of law as we have deemed necessary or appropriate
for purposes of our opinion. In addition, we have assumed (i) that the Merger
will be consummated in the manner contemplated by the Proxy Statement/Prospectus
and in accordance with the provisions of the Agreement, (ii) the truth and
accuracy of the representations and warranties made by HMT and Komag in the
Agreement, and (iii) the truth and accuracy of the certificates of
representations to be provided to us by HMT, Komag and Merger Sub.
Based upon and subject to the foregoing, in our opinion, the discussion
contained in the Registration Statement under the caption "Material United
States federal income tax considerations of the Merger," subject to the
limitations and qualifications described therein, sets forth the material
federal income tax considerations generally applicable to the Merger. Because
this opinion is being delivered prior to the Effective Time of the Merger, it
must be considered prospective and dependent on future events. There can be no
assurance that changes in the law will not take place which could affect the
United States federal income tax consequences of the Merger or that contrary
positions may not be taken by the Internal Revenue Service.
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Komag, Incorporated
August 16, 2000
Page 2
No opinion is expressed as to any federal income tax consequences
of the Merger except as specifically set forth herein, and this opinion may not
be relied upon except with respect to the consequences specifically discussed
herein.
This opinion is furnished to you solely for use in connection
with the Registration Statement. We hereby consent to the filing of this opinion
as an exhibit to the Registration Statement. We also consent to the reference to
our firm name wherever appearing in the Registration Statement with respect to
the discussion of the material federal income tax consequences of the Merger,
including the Proxy Statement/Prospectus constituting a part thereof, and any
amendment thereto. In giving this consent, we do not thereby admit that we are
in the category of persons whose consent is required under Section 7 of the
Securities Act of 1933, as amended, or the rules and regulations of the
Securities and Exchange Commission thereunder, nor do we thereby admit that we
are experts with respect to any part of such Registration Statement within the
meaning of the term "experts" as used in the Securities Act of 1933, as amended,
or the rules and regulations of the Securities and Exchange Commission
thereunder.
Very truly yours,
/s/ WILSON SONSINI GOODRICH & ROSATI
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WILSON SONSINI GOODRICH & ROSATI
Professional Corporation
