<SEC-DOCUMENT>0001179110-20-003497.txt : 20200311
<SEC-HEADER>0001179110-20-003497.hdr.sgml : 20200311
<ACCEPTANCE-DATETIME>20200311181204
ACCESSION NUMBER:		0001179110-20-003497
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20181205
FILED AS OF DATE:		20200311
DATE AS OF CHANGE:		20200311

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MULLER EDWARD R
		CENTRAL INDEX KEY:			0001180211

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38373
		FILM NUMBER:		20706558

	MAIL ADDRESS:	
		STREET 1:		C/O AEROVIRONMENT, INC.
		STREET 2:		900 INNOVATORS WAY
		CITY:			SIMI VALLEY
		STATE:			CA
		ZIP:			93065

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Transocean Ltd.
		CENTRAL INDEX KEY:			0001451505
		STANDARD INDUSTRIAL CLASSIFICATION:	DRILLING OIL & GAS WELLS [1381]
		IRS NUMBER:				980599916
		STATE OF INCORPORATION:			V8
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		TURMSTRASSE 30
		CITY:			STEINHAUSEN
		STATE:			V8
		ZIP:			6312
		BUSINESS PHONE:		41 41 749 0500

	MAIL ADDRESS:	
		STREET 1:		TURMSTRASSE 30
		CITY:			STEINHAUSEN
		STATE:			V8
		ZIP:			6312
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-12-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001451505</issuerCik>
        <issuerName>Transocean Ltd.</issuerName>
        <issuerTradingSymbol>RIG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001180211</rptOwnerCik>
            <rptOwnerName>MULLER EDWARD R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>TURMSTRASSE 30</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>STEINHAUSEN</rptOwnerCity>
            <rptOwnerState>V8</rptOwnerState>
            <rptOwnerZipCode>6312</rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Registered Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2018-12-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>40</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12687</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to the Agreement and Plan of Merger dated September 3, 2018, among Ocean Rig UDW Inc. (Ocean Rig), Transocean Ltd., Transocean Oceanus Holdings Limited and Transocean Oceanus Limited, at the effective time of the merger, each outstanding ordinary share of Ocean Rig was converted into the right to receive 1.6128 newly issued shares of Transocean Ltd., having a market value of $9.92 per share as of the close of trading on the trading day immediately preceding the effective time of the merger, and $12.75 in cash. The reporting person owned 25 Ocean Rig shares at the effective time of the merger, which converted into the right to receive 40 Transocean Ltd. shares. The Ocean Rig shares owned prior to the effective time of the merger, and the Transocean Ltd. shares received as merger consideration, were held within a trust on which the reporting person is a trustee, but in an account whose investment decisions were managed by a third party.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Daniel Ro-Trock By Power of Attorney</signatureName>
        <signatureDate>2020-03-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
