Transocean Ltd.
Blandonnet International Business Center
Building F, 7th Floor
Chemin de Blandonnet 2
1214 Vernier
Switzerland

Homburger AG

Prime Tower

Hardstrasse 201 | CH–8005 Zurich

P.O. Box 314 | CH–8037 Zurich

T  +41 43 222 10 00

F  +41 43 222 15 00

lawyers@homburger.ch

December 6, 2016

325336|7234634v6

I.

Basis of Opinion

(i)

an execution copy of the agreement and plan of merger among Transocean Ltd., Transocean Partners Holdings Limited, TPHL Holdings LLC and Transocean Partners LLC, dated as of July 31, 2016 (as amended by the Amendment to Agreement and Plan of Merger to the Agreement and Plan of Merger, dated as of November 21, 2016, the Merger Agreement);

(ii)

an execution copy of the option agreement, dated as of July 31, 2016, by and between Transocean Ltd. and Transocean Partners Holdings Limited (as amended by the amendment agreement to the Option Agreement, dated as of November 22, 2016, the Option Agreement);

(iii)

a copy of the Articles of Association (Statuten) of the Company in the form as deposited with the Commercial Register of the Canton of Zug, Switzerland, dated as of May 12, 2016 (the Articles of Association);

(iv)

a copy of the executed exercise notice of TPHL, dated December 6, 2016 (the Exercise Notice), addressed to the Company and Credit Suisse AG (the Agent) to subscribe for, and purchase and receive, the 23,834,608 newly issued Registered Shares out of the Company's conditional share capital pursuant to Article 6 of the Articles of Association (the Conditional Share Capital);

(v)

a copy of the executed agent notice of the Agent, dated December 6, 2016, confirming receipt by the Agent of the exercise notice by TPHL pursuant to the Option Agreement;

(vi)

a copy of the executed confirmation of credit advice issued by the Agent, dated December 6, 2016, confirming receipt by the Agent of the contribution in money by TPHL of an amount at least equal to the exercise price as set forth in the Exercise Notice;

(vii)

a copy of the Company's uncertificated share register (Wertrechtebuch), dated December 6, 2016, evidencing the registration of TPHL as the holder of the 23,834,608 Registered Shares newly issued out of the Conditional Share Capital for which the option under the Option Agreement (the Option) has been exercised pursuant to the Exercise Notice;

(viii)

a copy of an electronic excerpt from the Commercial Register of the Canton of Zug, Switzerland, for the Company, dated as of December 6, 2016 (the Excerpt);

(ix)

a copy of (1) the resolutions of the Company's board of directors, dated as of May 13, 2016 and August 12, 2016 and (2) the resolutions of the Company's special committee as of May 27, 2016, July 25, 2016 and November 17, 2016 (the Resolutions); and

(x)

a certificate provided by the secretary of the Company's board of directors, dated as of December 6, 2016, relating to the Resolutions and the Excerpt.

II.

Assumptions

(a)

the filing of the Registration Statement with the SEC has been authorized by all necessary actions under all applicable laws other than Swiss law;

(b)

all copies, fax copies or electronic versions of the documents produced to us conform to the respective original documents and the originals of such documents were executed in the manner and by the individuals appearing on the respective copies;

(c)

all signatures appearing on all original documents or copies thereof which we have examined are genuine;

(d)

all factual information contained in, or material statements given in connection with, the Documents are true and accurate;

(e)

the Registration Statement has been filed by the Company;

(f)

the 23,834,608 Registered Shares issued out of the Company's Conditional Share Capital will be listed on the New York Stock Exchange in accordance with applicable laws and regulations;

(g)

all authorizations, approvals, consents, licenses, exemptions and other requirements, other than those required under Swiss law for the issuance of the up to 23,834,608 Registered Shares, for the filing of the Registration Statement or for any other activities carried on in view of, or in connection with, the performance of the obligations expressed to be undertaken by the Company in the Registration Statement have been duly obtained and are and will remain in full force and effect, and any related conditions to which the parties thereto are subject have been satisfied; and

(h)

the Documents (other than the Articles of Association and the Excerpt) are correct, complete and up-to-date.

III.

Opinion

1.

The Company is a corporation (Aktiengesellschaft) duly incorporated and validly existing under the laws of Switzerland with all requisite corporate power and authority to enter into, to perform and to conduct its business as described in the Articles of Association.

2.

The Company's share capital registered in the Commercial Register of the Canton of Zug amounts to CHF 37,096,738.20, divided into 370,967,382 Registered Shares with a par value of CHF 0.10 each. Such Registered Shares have been validly issued, fully paid and are non-assessable.

(i)

The 23,834,608 Registered Shares for which the Option has been exercised pursuant to the Exercise Notice have been validly issued and fully paid and are non-assessable.

IV.

Qualifications

(a)

The lawyers of our firm are members of the Zurich bar and do not hold themselves out to be experts in any laws other than the laws of Switzerland. Accordingly, we are opining herein as to Swiss law only and we express no opinion with respect to the applicability thereto, or the effect thereon, of the laws of any other jurisdiction.

(b)

The exercise of voting rights and rights related thereto with respect to the 23,834,608 Registered Shares is only permissible after registration in the Company's share register as a shareholder with voting rights in accordance with the provisions of, and subject to the limitations provided in, the Articles of Association.

(c)

We express no opinion as to any commercial, accounting, tax, calculating, auditing or other non-legal matter.

(d)

We have not investigated or verified the truth or accuracy of the information contained in the Registration Statement, nor have we been responsible for ensuring that no material information has been omitted from it;

(e)

The issuance of the 23,834,608 Registered Shares out of Conditional Share Capital must be confirmed by the auditor of the Company, and amended Articles of Association of the Company reflecting the issuance of the 23,834,608 Registered Shares out of the Conditional Share Capital, together with ascertainments by the Company's board of directors in a public deed and said confirmation by the Company's auditor, must be filed with the competent commercial register no later than three months after the end of the Company's fiscal year 2016.