Exhibit 5.1

[BAKER & MCKENZIE LETTERHEAD]

Geneva, May 17, 2012

MA / JIG

Board of Directors

Weatherford International Ltd.

(a Swiss joint-stock corporation)

Prospectus Supplement to Registration Statement on Form S-3

Gentlemen,

We have acted as Swiss counsel to Weatherford International Ltd., a joint-stock corporation organized under the laws of Switzerland (the “Company”), in connection with the Company’s Registration Statement on Form S-3 (No. 333-174485) (the “Registration Statement”) filed under the U.S. Securities Act of 1933, as amended (the “Securities Act”), with the U.S. Securities and Exchange Commission (“SEC”) on May 25, 2011 and the prospectus supplement to be filed with the SEC under Rule 424(b) of the Securities Act on May 17, 2012 (the “Prospectus Supplement”) relating to 3,084,096 of the Company’s registered shares, par value 1.16 Swiss francs per share (the “Registered Shares”), all of which shares are registered under the Registration Statement for resale by the selling shareholders named in the Prospectus Supplement. The Registered Shares were issued pursuant to that certain Agreement, dated May 17, 2012, by and between the Company and the shareholders as listed in Annex A of this opinion (“the Shareholders”), and the related annexes and implementing documents (collectively, the “SPA”), and the related Registration Rights Agreement, dated May 17, 2012, by and among the Company and the Shareholders (the “Registration Rights Agreement”).

In acting as such counsel, we have examined the following (collectively, the “Documents”):

Except as stated above, we have not, for the purposes of this opinion, examined any other contract, instrument or other document affecting or relating to the above mentioned documents.

For the purpose of giving this opinion we have relied on the search for any pending corporate actions with respect to the Company made in the Register of Commerce of Zug on May 17, 2012, and the excerpt referred to under paragraph B(g) above, to the exclusion of any other searches or inquiries.

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In giving this opinion, we have assumed:

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In rendering our opinion, we have relied, to the extent we deem necessary and proper, on warranties and representations as to certain factual matters contained in the above mentioned documents.

Based on the foregoing, and subject to the limitations and qualifications made herein, we are of the opinion that the Registered Shares are legally issued, fully paid and non assessable (which term means when used herein that no further sums are required to be paid by the holders thereof in connection with the issue of such shares).

This opinion is subject to the following qualifications:

In this opinion, Swiss legal concepts are expressed in English terms and not in their original French, German or Italian terms. The concepts concerned may not be identical to the concepts described by the same English terms as they exist under the laws of other jurisdictions. This opinion may, therefore, only be relied upon under the express condition that any issues of interpretation or liability arising thereunder will be governed by Swiss law and be brought before a Swiss court.

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We hereby consent to the filing of this opinion as an exhibit to the Company’s Current Report on Form 8-K filed the date hereof and to the reference to our firm under the caption “Legal Matters” in the Prospectus Supplement. In giving this consent, we do not hereby admit that we come within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the SEC promulgated thereunder or Item 509 of Regulation S-K.

This opinion is issued solely for the purposes of the filing of the Prospectus Supplement and the issuance of the Registered Shares by the Company as described in the Prospectus Supplement and is not to be relied upon in respect of any other matter.

This opinion is given only on behalf of Baker & McKenzie Geneva and not on behalf of any other member firms of Baker & McKenzie International. In this opinion, the expression “we,” “us” and “our” and like expressions should be construed accordingly.

Very truly yours,

/s/ Martin Anderson

Martin Anderson

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EXHIBIT A

SHAREHOLDERS INFORMATION

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