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[Letterhead of Sullivan & Cromwell]
Exhibit 5.1
November 8, 2000
UBS AG,
Bahnhofstrasse 45,
Zurich,
Switzerland.
Dear Sirs:
In connection with the registration under the Securities Act of 1933
(the "Act") of $2,000,000,000 aggregate amount of medium term notes, Series A
(the "Securities") of UBS AG, a corporation organized under the laws of
Switzerland (the "Company"), we, as your counsel, have examined such corporate
records, certificates and other documents, and such questions of law, as we have
considered necessary or appropriate for the purposes of this opinion.
Upon the basis of such examination, we advise you that, in our opinion,
when the Registration Statement has become effective under the Act, the
Indenture relating to the Securities has been duly authorized, executed and
delivered, the terms of the Securities and of their issuance and sale have been
duly established in conformity with the Indenture so as not to violate any
applicable law or result in a default
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under or breach of any agreement or instrument binding upon the Company and so
as to comply with any requirement or restriction imposed by any court or
governmental body having jurisdiction over the Company, and the Securities have
been duly executed and authenticated in accordance with the Indenture and issued
and sold as contemplated in the Registration Statement, the Securities will
constitute valid and legally binding obligations of the Company, subject to
bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and
similar laws of general applicability relating to or affecting creditors' rights
and to general equity principles.
We note, as of the date of this opinion, a judgment for money in an
action based on a Security denominated in a foreign currency or currency unit in
a Federal or state court in the United States ordinarily would be enforced in
the United States only in United States dollars. The date used to determine the
rate of conversion of the foreign currency or currency unit in which a
particular Security is denominated into United States dollars will depend upon
various factors, including which court renders the judgment. In the case of a
Security denominated in a foreign currency or currency unit,
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a state court in the State of New York would be required under Section 27 of the
New York Judiciary Law to render such judgement in the foreign currency or
currency unit in which the Security is denominated, and such judgment would be
converted into United States dollars at the exchange rate prevailing on the date
of entry of the judgment.
The foregoing opinion is limited to the Federal laws of the United
States and the laws of the State of New York, and we are expressing no opinion
as to the effect of the laws of any other jurisdiction. In rendering the
foregoing opinion, we have assumed that UBS has been duly incorporated and is an
existing corporation in good standing under the laws of Switzerland, and that
all corporate action by UBS related to the Securities was duly authorized as a
matter of Swiss law.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the references to us under the heading "Validity
of Notes" in the Prospectus. In giving such consent, we do not thereby admit
that we are in
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the category of persons whose consent is required under Section 7 of the Act.
Very truly yours,
/s/ SULLIVAN & CROMWELL
