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Exhibit 8.1
[Letterhead of Sullivan & Cromwell]
September 21, 2000
UBS AG,
Bahnhofstrasse 45,
Zurich,
Switzerland.
Ladies and Gentlemen:
We have acted as your counsel in connection with your
Registration Statement on Form F-4 filed with the Securities and Exchange
Commission on the date hereof (the "Registration Statement").
We hereby confirm to you that our opinion is as set forth
under the caption "Taxation -- The Merger -- United States Federal Income
Taxation" and "Taxation -- Ownership of UBS Shares -- United States Federal
Income Taxation" in the Proxy Statement/Prospectus included in the related
Registration Statement, subject to the limitations contained therein.
We hereby consent to the filing of this opinion as an exhibit
to that Registration Statement. In giving such consent, we do not admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities Act of 1933, as amended.
Very truly yours,
Sullivan & Cromwell
