<SEC-DOCUMENT>0001181431-12-021302.txt : 20120402
<SEC-HEADER>0001181431-12-021302.hdr.sgml : 20120402
<ACCEPTANCE-DATETIME>20120402194444
ACCESSION NUMBER:		0001181431-12-021302
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20120331
FILED AS OF DATE:		20120402
DATE AS OF CHANGE:		20120402

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WILLIAM & SUSAN OBERNDORF TRUST
		CENTRAL INDEX KEY:			0001252467

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34776
		FILM NUMBER:		12735079

	MAIL ADDRESS:	
		STREET 1:		591 REDWOOD HIGHWAY
		STREET 2:		STE 3215
		CITY:			MILL VALLEY
		STATE:			CA
		ZIP:			94941

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			JOHN H SCULLY LIVING TRUST
		CENTRAL INDEX KEY:			0001273627

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34776
		FILM NUMBER:		12735078

	MAIL ADDRESS:	
		STREET 1:		591 REDWOOD HIGHWAY
		STREET 2:		SUITE 3215
		CITY:			MILL VALLEY
		STATE:			CA
		ZIP:			94941

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			OBERNDORF WILLIAM E
		CENTRAL INDEX KEY:			0001218663

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34776
		FILM NUMBER:		12735080

	MAIL ADDRESS:	
		STREET 1:		SPO PARTNERS & CO
		STREET 2:		591 REDWOOD HWY STE 3215
		CITY:			MILL VALLEY
		STATE:			CA
		ZIP:			94941

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Oasis Petroleum Inc.
		CENTRAL INDEX KEY:			0001486159
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1001 FANNIN STREET
		STREET 2:		SUITE 1500
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77002
		BUSINESS PHONE:		281-404-9500

	MAIL ADDRESS:	
		STREET 1:		1001 FANNIN STREET
		STREET 2:		SUITE 1500
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77002

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Edward & Elizabeth McDermott Trust
		CENTRAL INDEX KEY:			0001545752
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34776
		FILM NUMBER:		12735077

	BUSINESS ADDRESS:	
		STREET 1:		591 REDWOOD HIGHWAY
		STREET 2:		SUITE 3215
		CITY:			MILL VALLEY
		STATE:			CA
		ZIP:			94941
		BUSINESS PHONE:		415-383-6600

	MAIL ADDRESS:	
		STREET 1:		591 REDWOOD HIGHWAY
		STREET 2:		SUITE 3215
		CITY:			MILL VALLEY
		STATE:			CA
		ZIP:			94941
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd339883.xml
<DESCRIPTION>FORM 4 - WEO DEPARTURE
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0305</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-03-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001486159</issuerCik>
        <issuerName>Oasis Petroleum Inc.</issuerName>
        <issuerTradingSymbol>OAS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001218663</rptOwnerCik>
            <rptOwnerName>OBERNDORF WILLIAM E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>591 REDWOOD HIGHWAY, SUITE 3215</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILL VALLEY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94941</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001252467</rptOwnerCik>
            <rptOwnerName>WILLIAM &amp; SUSAN OBERNDORF TRUST</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>591 REDWOOD HIGHWAY, SUITE 3215</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILL VALLEY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94941</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001273627</rptOwnerCik>
            <rptOwnerName>JOHN H SCULLY LIVING TRUST</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>591 REDWOOD HIGHWAY , SUITE 3215</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILL VALLEY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94941</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001545752</rptOwnerCik>
            <rptOwnerName>Edward &amp; Elizabeth McDermott Trust</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>591 REDWOOD HIGHWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3215</rptOwnerStreet2>
            <rptOwnerCity>MILL VALLEY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94941</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>0</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9566749</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">On March 31, 2012, the John H. Scully Living Trust (&quot;JHS Trust&quot;) and the Edward &amp; Elizabeth McDermott Trust (&quot;EHM Trust&quot;) purchased one-third of the outstanding shares of SPO Advisory Corp. (&quot;SPO Corp.&quot;) previously owned by the William E. &amp; Susan C. Oberndorf Trust. William E. Oberndorf (&quot;WEO&quot;) left the SPO reporting group on March 31, 2012 and is no longer a controlling person of SPO Corp. Following the transaction which caused this filing, WEO beneficially owns 50,800 shares of the Issuer's common stock held in the WEO individual retirement account, which is self directed.  These shares are no longer included in the SPO filing group.</footnote>
        <footnote id="F2">Additionally, following the transaction which caused this filing, 9,207,149 shares of the Issuer's common stock are owned directly by SPO Partners II, L.P. (&quot;SPO Partners&quot;), and may be deemed to be indirectly beneficially owned by (i) SPO Advisory Partners, L.P. (&quot;SPO Advisory&quot;), the sole general partner of SPO Partners, (ii) SPO Corp., the sole general partner of SPO Advisory, and (iii) John H. Scully (&quot;JHS&quot;) and Edward H. McDermott (&quot;EHM&quot;), the two controlling persons of SPO Corp.  Additionally, 308,800 shares of the Issuer's common stock are owned directly by San Francisco Partners, L.P. (&quot;SF Partners&quot;), and may be deemed to be indirectly beneficially owned by (i) SF Advisory Partners, L.P. (&quot;SF Advisory&quot;), the sole general partner of SF Partners, (ii) SPO Corp., the sole general partner of SF Advisory, and (iii) JHS and EHM, the two controlling persons of SPO Corp.</footnote>
        <footnote id="F3">Additionally, following the transaction which caused this filing, JHS beneficially owns 15,100 shares of the Issuer's common stock held in the JHS individual retirement accounts, which are self directed.  Additionally, EHM beneficially owns 1,000 shares of the Issuer's common stock held in the EHM individual retirement accounts, which are self directed.</footnote>
    </footnotes>

    <remarks>The individuals and entities listed in the Notes above may be deemed to form a &quot;group&quot;, as such term is defined in Rule 13d-5(b)(1) promulgated under the Securities Exchange Act of 1934. This filing shall not be deemed as an admission by the Reporting Person that such person is, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the beneficial owner of any equity securities covered by this statement. The Reporting Person disclaims beneficial ownership of the reported securities except to the extent of his pecuniary interest, if any, therein.</remarks>

    <ownerSignature>
        <signatureName>Kim M. Silva, Attorney-in-fact</signatureName>
        <signatureDate>2012-04-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
