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                                                                     EXHIBIT 8.3


                          [STIKEMAN ELLIOTT LETTERHEAD]


                                                               September 6, 2002

Nabors Industries Ltd.
c/o The Corporate Secretary Limited
Whitepark House
White Park Road
Bridgetown, Barbados



Ladies and Gentlemen:

         We have acted as Canadian tax counsel to Nabors Industries Ltd., a
Bermuda exempted company ("Nabors"), in connection with the registration of the
Shelf Registration Statement on Form S-3 (the "Registration Statement") with the
Securities and Exchange Commission (the "Commission") under the Securities Act
of 1933, as amended (the "Securities Act"), on September 6, 2002, with respect
to the registration of up to 1,000,000 Nabors common shares par value US $.001
per share. In addition, Ryan Energy Technologies Inc. ("Ryan") has prepared, and
we have reviewed, a draft Management Information Circular and Proxy Statement
(the "Proxy Statement"), the final version of which is expected to be dated on
or about September 6, 2002. The Proxy Statement relates to the proposed
acquisition of Ryan by Nabors upon the terms and conditions set forth in the
Arrangement Agreement dated as of August 12, 2002, and the exhibits thereto (the
"Arrangement Agreement") implemented by means of an exchange of Ryan shares
(other than shares held by holders who perfected their dissent rights) for cash,
exchangeable shares of Nabors Exchangeco (Canada) Inc. ("Exchangeable Shares"),
or a combination of cash and Exchangeable Shares, pursuant to a plan of
arrangement in substantially the form set forth as Schedule B to the Arrangement
Agreement (the "Plan of Arrangement").

         In connection with this opinion, we have examined the Registration
Statement, the Proxy Statement, the Arrangement Agreement and such other
documents and corporate records as we have deemed necessary or appropriate in
order to enable us to render the opinion below, including a certificate of a
duly qualified officer of Nabors as to certain factual matters. For purposes of
this opinion, we have assumed (i) the validity and accuracy of the documents and
corporate records that we have examined and the facts and representations
concerning the registration of Nabors common shares that have come to our
attention during our engagement, (ii) the genuineness of all signatures, the
legal



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capacity of all natural persons, the authenticity of all documents submitted to
us as originals, the conformity to original documents of all documents submitted
to us as certified or photostatic copies and the authenticity of the originals
of such documents, (iii) that the final version of the Proxy Statement that is
mailed to Ryan shareholders and optionholders will be substantially the same as
the draft Proxy Statement that we have reviewed, and (iv) that the issuance of
Nabors common shares pursuant to the Registration Statement will be consummated
in the manner described in the Registration Statement.

         This opinion is based on the current provisions of the Income Tax Act
(Canada) and the regulations thereunder, the current provisions of the
Convention Between the United States of America and Canada with Respect to Taxes
on Income and on Capital, signed September 26, 1980, as amended, and our
understanding of the current published administrative practices of the Canada
Customs and Revenue Agency. This opinion takes into account all specific
proposals to amend the Income Tax Act (Canada) and the regulations that have
been publicly announced by the Minister of Finance (Canada) prior to the date
hereof and assumes that all of these proposed amendments will be enacted in
their present form. No assurances can be given that any proposed amendments will
be enacted in the form proposed, if at all. Except for the foregoing, this
opinion does not take into account or anticipate any changes in law, whether by
legislative, administrative or judicial decision or action, nor does it take
into account provincial, territorial or foreign income tax legislation or
considerations, which may differ from the Canadian federal income tax
considerations described in the Registration Statement. In addition, we have
assumed that all parties to the Arrangement Agreement have acted, and will act,
in accordance with the terms of such Arrangement Agreement and that the
Arrangement Agreement was consummated pursuant to the terms and conditions set
forth therein without the waiver or modification of any such terms and
conditions.

         Based upon and subject to the foregoing, the confirmation by Nabors of
the accuracy of certain assumptions and representations underlying this opinion,
and the qualifications, limitations and assumptions contained in the portion of
the Registration Statement captioned "Income Tax Considerations - Canadian
Federal Income Tax Considerations", we hereby confirm, as to matters of Canadian
federal income tax law, our opinion contained in the Registration Statement
under the caption "Income Tax Considerations - Canadian Federal Income Tax
Considerations".

         We have not considered and render no opinion on any aspect of law other
than as expressly set forth above.

         This opinion is furnished to you solely for use in connection with the
Registration Statement and may not be used for any other purpose without our
prior written consent. We hereby consent to the filing of this opinion as an
exhibit to the Registration Statement and to the use of our name under the
captions "Income Tax Considerations - Canadian Federal Income Tax
Considerations" and "Legal Matters" in the Registration Statement. In giving
such 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.

                                                     Yours very truly,

                                                     /s/ Stikeman Elliott


