UsetheselinkstorapidlyreviewthedocumentProspectusSupplementTABLEOFCONTENTS

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FiledPursuanttoRule424(b)(5)RegistrationNo.333-221706

Theinformationinthispreliminaryprospectussupplementandtheaccompanyingprospectusisnotcompleteandmaybechanged.Thispreliminaryprospectussupplementandtheaccompanyingprospectusarenotanoffertosellthesesecurities,andarenotsolicitinganoffertobuythesesecurities,inanyjurisdictionwheretheofferorsaleisnotpermitted.

Subjecttocompletion,datedJanuary10,2018

PRELIMINARYPROSPECTUSSUPPLEMENT(ToProspectusdatedNovember21,2017)

Enscoplc$500,000,000%SeniorNotesdue2026

Thisisanofferingof$500,000,000aggregateprincipalamountofour%SeniorNotesdue2026(the"notes").Thenoteswillmatureon,2026.Wewillpayinterestonthenotesonandofeachyear,commencing,2018.Wemayredeemthenotes,inwholeatanytimeorinpartfromtimetotimepriortotheirmaturity,asdescribedunder"DescriptionofNotes—OptionalRedemption."

Thenoteswillbeourseniorunsecuredobligationsandwillrankequallyinrightofpaymentwithallofourexistingandfutureseniorunsecureddebt.Thenoteswillbestructurallysubordinatedtoalldebtandotherliabilitiesofoursubsidiariesandeffectivelysubordinatedtooursecureddebttotheextentofthevalueoftheassetssecuringsuchdebt.

Ifachangeofcontroltriggeringeventoccurs,unlesswehaveexercisedouroptiontoredeemthenotes,wewillberequired,subjecttocertainexceptions,tomakeanoffertoeachholderofnotestorepurchasealloranypartofthatholder'snotesforcashequalto101%oftheprincipalamountofthenotestoberepurchased,plusaccruedandunpaidinterest,ifany,onthosenotestotherepurchasedate.

WeareapplyingforlistingofthenotesontheNewYorkStockExchange("NYSE").WeexpecttradinginthenotesontheNYSEtobeginwithin30daysaftertheoriginalissuedate.Currently,thereisnopublicmarketforthenotes.Ifsuchlistingisobtained,wehavenoobligationtomaintainsuchlisting,andwemaydelistthenotesatanytime.

Investinginthenotesinvolvesrisks.See"RiskFactors"beginningonpageS-10.

NeithertheSecuritiesandExchangeCommission("SEC")noranystatesecuritiescommissionhasapprovedordisapprovedofthesesecuritiesordeterminedifthisprospectussupplementortheaccompanyingprospectusistruthfulorcomplete.Anyrepresentationtothecontraryisacriminaloffense.

Theunderwritersexpecttodeliverthenotesinbook-entryformonlythroughthefacilitiesofTheDepositoryTrustCompanyfortheaccountsofitsparticipants,includingClearstreamBanking,SA,andEuroclearBankSA/NV,asoperatoroftheEuroclearSystem,againstpaymentinNewYork,NewYork,onorabout,2018.

Joint Global Coordinators and Bookrunners

JointBook-RunningManagers

Co-Manager

PerNote TotalInitialpricetopublic $ $Underwritingdiscount $ $Proceeds,beforeexpenses,toEnsco $ $

DeutscheBankSecurities Citigroup

BNPPARIBAS BofAMerrillLynchDNBMarkets HSBC MorganStanley

SEB

Thedateofthisprospectussupplementis,2018.

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ProspectusSupplement

Prospectus

EnforceabilityofCivilLiabilities S-iAboutThisProspectusSupplement S-iMarketandIndustryData S-iiRoundingAdjustments S-iiNon-GAAPFinancialMeasures S-iiForward-LookingStatements S-iiiWhereYouCanFindMoreInformation;IncorporationbyReference S-iiiSummary S-1RiskFactors S-10UseofProceeds S-14Capitalization S-15DescriptionofNotes S-17CertainU.S.FederalandU.K.TaxConsequences S-35Book-Entry,DeliveryAndForm S-42Underwriting S-46LegalMatters S-53Experts S-53

AboutthisProspectus 1WhereYouCanFindMoreInformation;IncorporationByReference 1ForwardLookingInformation 2RiskFactors 3TheCompany 3UseofProceeds 4RatioofEarningstoFixedCharges 4DescriptionofDebtSecurities 4DescriptionofClassAOrdinaryShares 5DescriptionofPreferenceSharesandOrdinaryShares 5DescriptionofWarrants 5DescriptionofSharePurchaseContracts 6DescriptionofGuarantees 6DescriptionofUnits 7PlanofDistribution 7LegalMatters 7Experts 7

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ENFORCEABILITYOFCIVILLIABILITIES

WeareapubliclimitedcompanyorganizedunderthelawsofEnglandandWales.Asaresult,itmaybedifficultforyoutoeffectserviceofprocessorenforcejudgmentsobtainedagainstuswithintheUnitedStates(the"U.S."),predicateduponthecivilliabilityprovisionsofthefederalsecuritieslawsoftheU.S.ThereisdoubtastotheenforceabilityofcivilliabilitiespredicatedonU.S.federalsecuritieslawsinEngland,eitherinoriginalactionsorinactionsforenforcementofjudgmentsofU.S.courts.

ABOUTTHISPROSPECTUSSUPPLEMENT

Thisdocumentconsistsoftwoparts.Thefirstpartisthisprospectussupplement,whichdescribesthespecifictermsofthenotesandthisofferingandaddstoandupdatesinformationcontainedintheaccompanyingprospectusandthedocumentsincorporatedbyreferenceintothisprospectussupplementandtheaccompanyingprospectus.Thesecondpart,theaccompanyingprospectus,providesmoregeneralinformationaboutthenotesandothersecuritiesthatmaybeofferedfromtimetotimeusingsuchprospectus,someofwhichgeneralinformationdoesnotapplytothisoffering.Generally,whenwerefertotheprospectus,wearereferringtobothpartsofthisdocumentcombined.Youshouldreadboththisprospectussupplementandtheaccompanyingprospectus,togetherwithadditionalinformationdescribedundertheheading"WhereYouCanFindMoreInformation;IncorporationbyReference."

Iftheinformationinthisprospectussupplementdiffersfromtheinformationintheaccompanyingprospectus,theinformationinthisprospectussupplementsupersedestheinformationintheaccompanyingprospectus.

Anystatementmadeinthisprospectussupplementorinadocumentincorporatedbyreferenceinthisprospectussupplementandtheaccompanyingprospectuswillbedeemedtobemodifiedorsupersededforpurposesofthisprospectussupplementtotheextentthatastatementcontainedinthisprospectussupplementorinanyothersubsequentlyfileddocumentthatisalsoincorporatedbyreferenceinthisprospectussupplementandtheaccompanyingprospectusmodifiesorsupersedesthatstatement.Anystatementsomodifiedorsupersededwillnotbedeemed,exceptassomodifiedorsuperseded,toconstituteapartofthisprospectussupplement.See"WhereYouCanFindMoreInformation;IncorporationbyReference."

Neitherwenortheunderwritershaveauthorizedanyonetoprovideanyinformationotherthanthatcontainedinthisprospectussupplementortheaccompanyingprospectusorincorporatedbyreferenceinthisprospectussupplementortheaccompanyingprospectusorinanyfreewritingprospectuspreparedbyoronbehalfofustowhichwehavereferredyou.Weandtheunderwriterstakenoresponsibilityfor,andcanprovidenoassuranceastothereliabilityof,anyotherinformationthatothersmaygiveyou.Neitherwenortheunderwritersaremakinganyofferorsaleofthesesecuritiesinanyjurisdictionwheretheofferisnotpermitted.Youshouldassumethattheinformationcontainedorincorporatedbyreferenceinthisprospectussupplement,theaccompanyingprospectusandanyfreewritingprospectusprovidedinconnectionwiththisofferingisaccurateonlyasoftherespectivedatesthereofor,inthecaseofinformationincorporatedbyreference,onlyasofthedateofsuchinformation,regardlessofthetimeofdeliveryofthisprospectussupplement,theaccompanyingprospectusoranyfreewritingprospectus.Ourbusiness,financialcondition,resultsofoperationsandprospectsmayhavechangedsincesuchdates.Itisimportantforyoutoreadandconsideralltheinformationcontainedinthisprospectussupplementandthe

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accompanyingprospectus,includingthedocumentsincorporatedbyreferencetherein,inmakingyourinvestmentdecision.

MARKETANDINDUSTRYDATA

Certainmarketandindustrydataincludedorincorporatedbyreferenceinthisprospectussupplementandintheaccompanyingprospectushavebeenobtainedfromthirdpartysourcesthatwebelievetobereliable.Wehavenotindependentlyverifiedsuchthirdpartyinformationandcannotassureyouofitsaccuracyorcompleteness.Suchdatainvolverisksanduncertaintiesandaresubjecttochangebasedonvariousfactors,includingthosediscussedundertheheading"RiskFactors"inthisprospectussupplementandthedocumentsincorporatedbyreferenceherein.

ROUNDINGADJUSTMENTS

Certainfiguresincludedinthisprospectussupplementhavebeensubjecttoroundingadjustments.Accordingly,figuresshownastotalsincertaintablesmaynotbeanexactarithmeticaggregationofthenumbersthatprecedethem.Percentagefiguresincludedinthisprospectussupplementhavenotinallcasesbeencalculatedonthebasisofsuchroundedfiguresbutonthebasisofsuchamountspriortorounding.Forthisreason,certainpercentageamountsinthisprospectussupplementmayvaryfromthoseobtainedbyperformingthesamecalculationsusingthefigurescontainedhereinorinthefinancialstatementsincorporatedbyreferenceherein.Certainotheramountsthatappearinthisprospectussupplementmaynotsumduetorounding.

NON-GAAPFINANCIALMEASURES

Thisprospectussupplementcontainscertainnon-GAAPfinancialmeasures,whicharefinancialmeasuresthateitherexcludeorincludeamountsthatarenotexcludedorincludedinthemostdirectlycomparablemeasurecalculatedandpresentedinaccordancewithU.S.generallyacceptedaccountingprinciples("GAAP")(suchmeasuresbeing,"non-GAAPfinancialmeasures").Specifically,thisprospectussupplementincludesthenon-GAAPfinancialmeasure"AdjustedEBITDA"asasupplementalmeasureofEnsco'sperformance.AdjustedEBITDAshouldnotbeconsideredasanalternativeto,ormoremeaningfulthan,operatingincome,netincome(loss)oranyotherperformancemeasurederivedinaccordancewithGAAPorasanalternativetocashflowsfromoperatingactivitiesoranyotherliquiditymeasurederivedinaccordancewithGAAP.

Enscodefines"AdjustedEBITDA"asnetincome(loss)beforeincome(loss)fromdiscontinuedoperations,otherincome(expense),incometaxexpense(benefit),interestexpense,depreciation,amortization,lossonimpairment,(gain)lossonassetdisposalsandtransactioncosts.ThedefinitionofAdjustedEBITDAmaynotbethesameassimilarlynamedmeasuresusedbyothercompanies.EnscohasincludedinformationregardingAdjustedEBITDAinthisprospectussupplementbecauseitsmanagementbelievesthatthismeasureisfrequentlyusedbysecuritiesanalysts,investorsandotherinterestedpartiesintheevaluationofissuersinEnsco'sindustry.Ensco'spresentationofAdjustedEBITDAshouldnotbeconstruedtoimplythatitsfutureresultswillbeunaffectedbyunusualornonrecurringitems.

AdjustedEBITDAhaslimitationsasananalyticaltool,andyoushouldnotconsiderthismeasureinisolationorasasubstituteforanalysesofEnsco'sincomeorcashflowsasreportedunderGAAP.EnscocompensatesfortheselimitationsbyrelyingprimarilyonitsGAAPresultsandusingAdjustedEBITDAonlyforsupplementalpurposes.AdjustedEBITDAshouldnotbeconsideredasameasureofdiscretionarycashavailabletoEnscotoinvestin

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thegrowthofitsbusinessorfunditscashneeds.PleaseseeEnsco'sauditedconsolidatedandunauditedcondensedconsolidatedfinancialstatementsandrelatednotestheretoincorporatedbyreferenceinthisprospectussupplement.ForadescriptionofhowAdjustedEBITDAiscalculatedfromEnsco'snetincome(loss)attributabletoEnscoandareconciliationofEnsco'sAdjustedEBITDAtonetincome(loss),seethesectionentitled"SummaryHistoricalFinancialInformation"includedelsewhereinthisprospectussupplement.

FORWARD-LOOKINGSTATEMENTS

Thisprospectussupplement,includingtheinformationincorporatedbyreferenceherein,includesforward-lookingstatements.Forward-lookingstatementsusuallyrelatetofutureeventsandareoftenidentifiedbythewords,"will,""may,""should,""continue,""anticipate,""believe,""expect,""plan,""forecast,""project,""estimate,""intend,""could,""might"andwordsofasimilarnature.Thesestatementsarenotguaranteesoffutureperformance,circumstancesorevents.Theyarebasedonfactsandcircumstancesasofthedatethestatementsaremade.Forward-lookingstatementsaresubjecttorisksanduncertaintiesthatcouldcauseactualresultstobemateriallydifferentfromthosesetforthinsuchforward-lookingstatements,includingbutnotlimitedto,therisksanduncertaintiesdescribedinourmostrecentAnnualReportonForm10-KandsubsequentlyfiledquarterlyreportsonForm10-Q.Pleasealsosee"RiskFactors"beginningonpageS-8ofthisprospectussupplementandtheriskfactorsincludedinPartI,Item1AofourAnnualReportonForm10-KfortheyearendedDecember31,2016andsubsequentlyfiledQuarterlyReportsonForm10-Qandothercautionarystatementsincludedinthisprospectussupplement,theaccompanyingprospectusandourotherfilingswiththeSEC,foradditionalinformationaboutrisksanduncertaintiesapplicabletotheforward-lookingstatements.

WHEREYOUCANFINDMOREINFORMATION;INCORPORATIONBYREFERENCE

Wefileannual,quarterlyandcurrentreports,proxystatementsandotherinformationwiththeSEC.Youmayreadandcopyanyreports,statementsorotherinformationonfileattheSEC'spublicreferenceroomat100FStreet,N.E.,Washington,D.C.,20549.PleasecalltheSECat1-800-SEC-0330forfurtherinformationonthepublicreferenceroom.OurSECfilingsarealsoavailabletothepublicfromcommercialdocumentretrievalservicesandareavailableattheInternetwebsitemaintainedbytheSECathttp://www.sec.gov.ThesereportsandotherinformationfiledbyuswiththeSECarealsoavailablefreeofchargeatourwebsiteatwww.enscoplc.com.Theinformationonorlinkedto/fromourwebsiteisnotpartof,andisnotincorporatedbyreferenceinto,theprospectus.

Weincorporateinformationintotheprospectusbyreference,whichmeansthatwediscloseimportantinformationtoyoubyreferringyoutoanotherdocumentfiledseparatelywiththeSEC.Theinformationincorporatedbyreferenceisdeemedtobepartoftheprospectus,excepttotheextentsupersededbyinformationcontainedhereinorbyinformationcontainedindocumentssubsequentlyfiledwiththeSEC.TheprospectusincorporatesbyreferencethedocumentssetforthbelowthathavebeenpreviouslyfiledwiththeSEC.Thesedocumentscontainimportantinformationaboutusandourfinancialcondition.

• Ensco'sAnnualReportonForm10-KfortheyearendedDecember31,2016(the"Form10-K");

• Ensco'sQuarterlyReportsonForm10-QforthequartersendedMarch31,2017,June30,2017andSeptember30,2017;

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• TheinformationincludedinEnsco'sDefinitiveProxyStatementonSchedule14AfiledonMarch31,2017totheextentincorporatedbyreferenceinPartIIIoftheForm10-K;

• Ensco'sCurrentReportsonForm8-KfiledonJanuary11,2017,January23,2017,March10,2017,May23,2017,May30,2017(tworeports;excludingItem7.01andrelatedexhibits),September28,2017,October5,2017(Item5.07only),October6,2017(excludingItem7.01andrelatedexhibits)(asamendedbyCurrentReportonForm8-K/AfiledonDecember15,2017(the"DecemberForm8-K/A")),October13,2017,October25,2017(excludingItem2.02andrelatedexhibits)andDecember15,2017(the"DecemberForm8-K");and

• Thefinancialstatementsandproformafinancialinformationfiledasexhibits99.1oftheDecemberForm8-Kand99.2,99.3and99.4oftheDecemberForm8-K/A.

WealsoincorporatebyreferenceintotheprospectusadditionaldocumentsthatEnscomayfilewiththeSECunderSection13(a),13(c),14or15(d)oftheSecuritiesExchangeActof1934(the"ExchangeAct")fromthedateofthisprospectussupplementtothecompletionoftheofferingofthenotes.Wearenotincorporatingbyreferenceanyinformationfurnishedunderitems2.02or7.01(orcorrespondinginformationfurnishedunderitem9.01orincludedasanexhibit)inanypastorfutureCurrentReportonForm8-KthatwemayfilewiththeSEC,unlessotherwisespecifiedinsuchCurrentReport.

Youmayobtaincopiesofanyofthesefilingsasdescribedbelow,throughtheSECorthroughtheSEC'sInternetwebsiteasdescribedaboveorthroughourwebsiteasdescribedabove.Documentsincorporatedbyreferenceareavailablewithoutcharge,excludingallexhibitsunlessanexhibithasbeenspecificallyincorporatedbyreferenceintotheprospectus,byrequestingtheminwritingorbytelephoneat:

InvestorRelationsEnscoplc

5847SanFelipe,Suite3300Houston,Texas77057+1(713)789-1400

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SUMMARY

Thefollowingisasummaryofselectedinformationappearingelsewhereinthisprospectussupplement,theaccompanyingprospectusandthedocumentsincorporatedhereinbyreference.Thissummaryisnotcompleteanddoesnotcontainalltheinformationthatmaybeimportanttoyou.Youshouldcarefullyreadthisentireprospectussupplement,theaccompanyingprospectusandthedocumentsincorporatedhereinbyreferencetounderstandfullythetermsofthenotes,aswellasthetaxandotherconsiderationsthatareimportantinmakingyourinvestmentdecision.Unlessthecontextrequiresotherwiseorwespecificallyindicateotherwise,theterms"Ensco,""Company,""we,""us"and"our"refertoEnscoplctogetherwithallsubsidiariesandpredecessors.Forpurposesofthisprospectussupplement,thetwelvemonthperiodendedSeptember30,2017isreferredtohereinasthe"LTMPeriod"or"LTM."

Enscoplc

Enscoisaglobaloffshorecontractdrillingcompany.Wecurrentlyownandoperateanoffshoredrillingrigfleetof62rigs,includingthreerigsthatwecurrentlyhaveunderconstruction,withdrillingoperationsinmostofthestrategicmarketsaroundtheglobe.Ourrigfleetconsistsof12drillships,11dynamicallypositionedsemisubmersiblerigs,fourmooredsemisubmersiblerigsand38jackuprigs.Ouroffshorerigfleetistheworld'slargestamongstcompetitive,publicly-tradedcontractdrillersandincludesoneofthenewestultra-deepwaterfleetsintheindustryandaleadingpremiumjackupfleet.

Ourcustomersincludemanyoftheleadingnationalandinternationaloilcompanies,inadditiontomanyindependentoperators.Weareamongthemostgeographicallydiverseoffshoredrillingcompanies,withcurrentoperationsanddrillingcontractsspanning14countriesonsixcontinents.ThemarketsinwhichweoperateincludetheU.S.GulfofMexico,Mexico,Brazil,theMediterranean,theNorthSea,theMiddleEast,WestAfrica,AustraliaandSoutheastAsia.

Ourregisteredoffice(whichisourprincipalexecutiveoffice)islocatedat6ChesterfieldGardens,3rdFloor,London,UnitedKingdomW1J5BQandourtelephonenumberis+44(0)2076594660.WeareregisteredinEnglandandWalesundercompanynumber7023598.Ourwebsiteislocatedatwww.enscoplc.com.Theinformationonorlinkedto/fromourwebsiteisnotpartof,andisnotincorporatedbyreferenceinto,thisprospectussupplementortheaccompanyingprospectus.

RecentDevelopments

OnOctober6,2017,wecompletedouracquisitionofAtwoodOceanics,Inc.("Atwood").Theacquisitionisexpectedtostrengthenourpositionastheleaderinoffshoredrillingacrossawiderangeofwaterdepthsaroundtheworld.Theacquisitionsignificantlyenhancesthecapabilitiesofourrigfleetandimprovesourabilitytomeetfuturecustomerdemandwiththehighest-specificationassets.TotalconsiderationdeliveredtoAtwoodshareholdersintheacquisitionconsistedof132.2millionClassAordinaryshares.Inaddition,weutilizedacquiredcashof$445.4millionandcashonhandfromtheliquidationofshort-terminvestmentstorepayAtwood'sdebtandaccruedinterestof$1.3billion.Followingtheacquisition,wecontinuetofocusonourfleetmanagementstrategyinlightofthenewcompositionofourrigfleetandarereviewingourfleetaswecontinuepositioningEnscoforthefuture.Aspartofourreview,wemayactopportunisticallyfromtimetotimetomonetizeassetsinordertofurtherenhancethecompany'sliquidityprofile,inadditiontosellingordisposingofolder,lower-specificationornon-strategicrigs.

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InOctober2017,weamendedourrevolvingcreditfacility("CreditFacility")toextendthefinalmaturitydatebytwoyears.Previously,ourCreditFacilityhadaborrowingcapacityof$2.25billionthroughSeptember2019thatdeclinedto$1.13billionthroughSeptember2020.Subsequenttotheamendment,ourborrowingcapacityis$2.0billionthroughSeptember2019anddeclinesto$1.3billionthroughSeptember2020andto$1.2billionthroughSeptember2022.ThecreditagreementgoverningourCreditFacilityincludesanaccordionfeatureallowingustoincreasethecommitmentsexpiringinSeptember2022uptoanaggregateamountnottoexceed$1.5billion.TheamendmenttotheCreditFacilityalsoaddedguaranteesfromcertainofourrig-owningsubsidiaries.AsofSeptember30,2017,wewereincomplianceinallmaterialrespectswithourcovenantsundertheCreditFacility.WehadnoamountsoutstandingundertheCreditFacilityasofSeptember30,2017andDecember31,2016.

Weestimateourbacklogwas$2.8billionasofDecember31,2017ascomparedto$3.2billion,onaproformabasisadjustedfortheAtwoodacquisition,asofSeptember30,2017.Thereductionistheresultofa$260milliondeclineinbacklogwithrespecttoourfloatersprimarilyduetorevenuesrealizedduringthefourthquarter,partiallyoffsetbynewcontractawardsforENSCO8504,ENSCO8503andENSCO8505.Inaddition,ourjackupbacklogdeclinedby$110millionprimarilyduetorevenuesrealizedduringthefourthquarter,partiallyoffsetbynewcontractawardsforENSCO107andENSCO75.

Fromtimetotimeandparticularlyduringamarketdownturn,customersmayseektoengageindiscussionsregardingrevisedcommercialterms.WearecurrentlyengagedinsuchdiscussionswithourcustomerfortheENSCODS-8drillingcontract.Ourexperiencewiththesediscussionsarethattheycanleadtoablendandextendarrangement,nochangetothecontractorterminationaccordingtotheterminationforconvenienceprovisionsofthecontract.TherecanbenoassurancethatwewillbeabletocometoanagreementwithourcustomertorevisethecommercialtermsoftheENSCODS-8drillingcontractorthatthecontractwillnotbeterminated.

IfwenegotiateablendandextendarrangementwithourENSCODS-8customer,thecontracttermwouldbeextendedbutthedayratewouldbereducedforallorsomeportionofthecontractterm.Ifweareunabletoreachanagreementonrevisedmutuallybeneficialcommercialterms,thepartieswillremainsubjecttothetermsoftheDS-8contractwhichprovidethatifthecontractwereterminatedbythecustomerforconvenience,EnscowouldbepaiddailyterminationfeesthroughNovember2020.Forthefirst90daysfollowinganysuchtermination,thedailyterminationfeepaidbythecustomerwouldbeequaltothethencurrentoperatingdayrate,currentlyapproximately$620,000.FortheremainingtermthroughNovember2020,thedailyterminationfeewouldbeequalto75%ofthethencurrentoperatingdayrate,currentlyapproximately$465,000.IfthecontractwereterminatedforconvenienceandtheENSCODS-8werere-contractedpriortoNovember2020foradayratelessthantheoperatingdayrate,thecustomerwouldbeobligatedtocompensateusforanydifferencebetweenthere-contractedoperatingrateandthefulloperatingdayratethroughtotheendoftheDS-8contract.Inaccordancewiththesecontractterms,ifthedrillshipweretobere-contractedaftersuchatermination,wewouldnotanticipatethatourfinancialresultswouldbemateriallyimpactedduringthere-contractedperiod.WhilewebelievethattheENSCODS-8'stechnicalcapabilitiesandoperationalexcellencemakethedrillshipamarketableasset,shouldthedrillshipnotbere-contractedafteraterminationforconvenience,thereductionindayrateovertheremainingtermofthecontractwouldbesubstantiallyoffsetbyareductioninoperatingcosts,andwewouldexpectnomorethana$15millionperannumEBITDAimpactfortheremainingtermthroughNovember2020.

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ConcurrentTenderOffers

Concurrentlywiththisnotesoffering,weareconductingcashtenderoffersforupto$492.5millionaggregatepurchaseprice,subjecttoincreaseordecreaseandexclusiveofaccruedinterest,ofour(i)8.500%SeniorNotesdue2019(the"2019notes"),(ii)6.875%SeniorNotesdue2020(the"2020notes")and(iii)4.700%SeniorNotesdue2021(the"2021notes"and,togetherwiththe2019notesandthe2020notes,the"repurchasenotes")issuedbyusandPrideInternational,Inc.,ourwhollyownedsubsidiary("Pride").Thetenderoffersarescheduledtoexpireat11:59p.m.,NewYorkCitytime,onFebruary7,2018,subjecttoourrighttoextendeachtenderoffer.AsofSeptember30,2017,therewas$237.5millionaggregateprincipalamountof2019notesoutstanding,$450.9millionaggregateprincipalamountof2020notesoutstandingand$269.7millionaggregateprincipalamountof2021notesoutstanding.Weintendtofundthepurchaseoftherepurchasenotesinthetenderofferswiththenetproceedsfromthisoffering.ThetenderoffersarebeingmadepursuanttoanoffertopurchasedatedasofJanuary10,2018issuedinconnectionwiththetenderoffers.Thisprospectussupplementisnotanoffertopurchaseanyoftherepurchasenotes.

Theclosingofthetenderoffersareconditionedon,amongotherthings,thecompletionofthisofferingandourhavingobtainednetproceedsfromthisoffering(afterunderwritingdiscountbutbeforeexpenses)sufficienttopaytheaggregatepurchasepriceoftherepurchasenotesinthetenderoffers,whichconditionsmaybewaivedatouroption;however,thisofferingisnotconditionedontheclosingofthetenderoffers.Wearepermitted,amongotherthings,toamend,extendorterminateeachtenderoffer,andthereisnoassurancethatanyofthetenderofferswillbeconsummatedinaccordancewithitsterms,oratall.DeutscheBankSecuritiesInc.,CitigroupGlobalMarketsInc.,BNPParibasSecuritiesCorp.,DNBMarkets,Inc.,HSBCSecurities(USA)Inc.,MerrillLynch,Pierce,Fenner&SmithIncorporated,MorganStanley&Co.LLCandSkandinaviskaEnskildaBankenABareactingasdealermanagersforthetenderoffers.See"UseofProceeds"and"Capitalization."

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TheOffering

Thesummarybelowdescribestheprincipaltermsofthenotes.Certainofthetermsandconditionsdescribedbelowaresubjecttoimportantlimitationsandexceptions.The"DescriptionofNotes"sectionofthisprospectussupplementcontainsamoredetaileddescriptionofthetermsandconditionsofthenotes.Inthissection,"Ensco,""we"or"our"referstoEnscoplcandnotanyofitssubsidiaries.

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Issuer Enscoplc

NotesOffered $500,000,000principalamountof%SeniorNotesdue2026

MaturityDates Thenoteswillmatureon,2026.

InterestRates Interestonthenoteswillaccrueatarateof%perannum.

InterestPaymentDates Interestonthenoteswillbepayableonandofeachyear,commencing,2018,andwillaccruefromtheissuedate.

Ranking Thenotesareunsecuredandwillrankequallyinrightofpaymentwithallofourotherexistingandfutureseniorunsecuredindebtedness.Weareaholdingcompanywhoseassetsconsistofdirectandindirectownershipinterestsin,andwhosebusinessisconductedthrough,subsidiaries.Thenoteswillbestructurallysubordinatedtoanyandallexistingandfutureindebtedness,whetherornotsecured,andotherliabilitiesofoursubsidiaries,includingtheguaranteesbythesubsidiaryguarantorsunderourCreditFacility.Inaddition,thenoteswillbeeffectivelysubordinatedtoallofthesecuredindebtednessofEnscototheextentofthevalueoftheassetssecuringsuchdebt.AsofSeptember30,2017,(i)Enscoanditssubsidiarieshadoutstanding$4,882.7millionofconsolidatedindebtedness(including$958.1millionofrepurchasenotesoutstandingsubjecttothetenderoffers),(ii)Ensco'ssubsidiarieshadapproximately$1,987.9millionofindebtedness(consistingof$988.4million($688.4millionofwhicharerepurchasenotessubjecttothetenderoffers)issuedbyPride,$849.5millionissuedbyEnscoJerseyFinanceLimitedand$150.0millionissuedbyENSCOInternationalIncorporated),allofwhichwouldhavebeenguaranteedbyEnscoplc,and(iii)noneofEnscooritssubsidiarieshadanysecuredindebtedness.NeitherPridenorEnscoJerseyFinanceLimitedhasmaterialassetsoroperations.

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OptionalRedemption Wemayredeemanyorallofthenotes,inwholeatanytimeorinpartfromtimetotimepriortotheirmaturity.Ifweelecttoredeemthenotesbefore(threemonthspriortothematuritydate),wewillpayanamountequalto100%oftheprincipalamountofthenotesredeemedplusa"make-whole"premium.Ifweelecttoredeemthenotesonorafterthedatesetforthintheprecedingsentence,wewillpayanamountequalto100%oftheprincipalamountofthenotesredeemed.Wealsowillpayaccruedinterestonthenotesredeemedtotheredemptiondate.See"DescriptionofNotes—OptionalRedemption."

ChangeofControl IfaChangeofControlTriggeringEventoccurs(asdefinedunder"DescriptionofNotes—ChangeofControlOffer"),unlesswehaveexercisedouroptiontoredeemthenotesasdescribedabove,wewillberequired,subjecttocertainexceptions,tomakeanoffertoeachholderofnotestorepurchasealloranypartofthatholder'snotesforcashequalto101%oftheprincipalamountofthenotestoberepurchased,plusaccruedandunpaidinterest,ifany,onthosenotestotherepurchasedate.See"DescriptionofNotes—ChangeofControlOffer"inthisprospectussupplement.

TaxRedemption IfcertainchangesinthelawofanyrelevantTaxJurisdiction(asdefinedin"DescriptionofNotes—AdditionalAmounts")wouldrequireustowithholdtaxesonpaymentsonthenotesandpayAdditionalAmountswithrespectthereto,wemayredeemthenotesinwhole,butnotinpart,ataredemptionpriceof100%oftheaggregateprincipalamountthereof,togetherwithaccruedandunpaidinterest,ifany,totheredemptiondateandallAdditionalAmounts(asdefinedin"DescriptionofNotes"),ifany,whichotherwisewouldbepayabletothedateofredemption.See"DescriptionofNotes—RedemptionforChangesinTaxes."

AdditionalAmounts Ifanydeductionorwithholdingfor,oronaccountof,anyTaxesimposedbyanyTaxJurisdictionwillatanytimeberequiredtobemadefromanypaymentsmadeunderorwithrespecttothenotes,subjecttocertainexceptions,wewillpaysuchAdditionalAmountsasmaybenecessaryinorderthatthenetamountsreceivedinrespectofsuchpaymentsbyeachholderaftersuchwithholdingordeduction(includinganysuchdeductionorwithholdinginrespectofAdditionalAmounts)willequaltherespectiveamountswhichwouldhavebeenreceivedinrespectofsuchpaymentsintheabsenceofsuchwithholdingordeduction.See"DescriptionofNotes—AdditionalAmounts."

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CertainCovenants Theindenturegoverningthenotescontainscovenantslimitingourabilityandtheabilityofcertainsubsidiariesto:

• createliensoncertainassets;

• engageincertainsale/leasebacktransactions;and

• merge,consolidateortransferallorsubstantiallyallofourassets.

Thesecovenantsaresubjecttoanumberofimportantlimitationsandexceptions.

UseofProceeds Weintendtouseaportionofthenetproceedsfromthisofferingtofundthepurchaseprice,includinganyapplicabletenderpremium,andaccruedinterestpayablewithrespecttotherepurchasenotesinthetenderoffers.Weintendtouseanyremainingnetproceedsforgeneralcorporatepurposes.See"UseofProceeds."

FurtherIssues Wemay"reopen"thenotesandissueanunlimitedprincipalamountofadditionalnotesinthefuturewithouttheconsentoftheholders.

AbsenceofMarket Thenotesareanewissueofsecuritieswithnoestablishedtradingmarket.Wecannotprovideassuranceastothedevelopmentorliquidityofanymarketforthenotesasdescribedinthisprospectussupplement.See"Underwriting."

Listing WeareapplyingforlistingofthenotesontheNYSE.

GoverningLaw StateofNewYork

RiskFactors Investinginthenotesinvolvessubstantialrisks.See"RiskFactors"inthisprospectussupplementforadescriptionofcertainoftherisksyoushouldconsiderbeforeinvestinginthenotes.

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SUMMARYHISTORICALFINANCIALINFORMATION

ThefollowingtablepresentsEnsco'ssummaryhistoricalfinancialdataasofandfortheperiodsindicated.TheinformationsetforthbelowshouldbereadinconjunctionwithEnsco'sfinancialstatementsandaccompanyingnotestheretofiledwiththeSEConForm10-KandForm10-Qandreferredtoelsewhereinthisprospectussupplement.See"WhereYouCanFindMoreInformation;IncorporationbyReference."ThesummaryhistoricalfinancialinformationsetforthbelowasofandfortheyearsendedDecember31,2016,2015and2014hasbeentakenfromourauditedfinancialstatements.ThesummaryhistoricalfinancialinformationsetbelowasofandfortheninemonthperiodsendedSeptember30,2017and2016hasbeentakenfromourunauditedfinancialstatements.WehavederivedourconsolidatedfinancialinformationfortheLTMPeriodbyaddingoursummaryfinancialinformationfortheyearendedDecember31,2016andthesummaryfinancialinformationfortheninemonthsendedSeptember30,2017andsubtractingoursummaryfinancialinformationfortheninemonthsendedSeptember31,2016.TheunauditedproformacombinedfinancialdatafortheLTMPeriodreflectadjustmentstoourhistoricalfinancialresultsinconnectionwithouracquisitionofAtwood.TheunauditedproformacombinedstatementofoperationsdatagiveeffecttotheacquisitionasifsuchacquisitionhadoccurredatthebeginningoftheLTMPeriod.TheunauditedproformacombinedbalancesheetdatagiveeffecttotheacquisitionasifsuchacquisitionhadoccurredonSeptember30,2017.

TheresultsofoperationsfortheninemonthsendedSeptember30,2017andtheLTMPeriodarenotnecessarilyindicativeoftheresultsthatmaybeexpectedfortheentirefiscalyearendingDecember31,2017oranyfutureperiod.Further,theproformainformationsetforthbelow,whilehelpfulinillustratingthefinancialcharacteristicsofthecombinedcompanyunderonesetofassumptions,ispreliminaryanddoesnotreflectthepossibleimpactonthecombinedcompanythatmayresultasaconsequenceoftheacquisitionand,accordingly,doesnotattempttopredictorsuggestfutureresults.ItalsodoesnotnecessarilyreflectwhatthehistoricalresultsofthecombinedcompanywouldhavebeenhadourcompaniesbeencombinedduringtheLTMPeriod.YoushouldreadthedatawiththehistoricalconsolidatedfinancialstatementsandrelatednotesofEnscoandAtwoodcontainedintheirAnnualReportsonForm10-KfortheyearsendedDecember31,2016andSeptember30,2016,respectively,andtheirsubsequentlyfiledQuarterlyReportsonForm10-QforthequartersendedSeptember30,2017(solelyasitrelatestoEnsco),June30,2017,March31,2017andDecember31,2016(solelyasitrelatedtoAtwood).

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Historical

TwelveMonthsEndedSeptember30,

2017

NineMonthsEnded

September30,

YearEndedDecember31,

ProFormaCombined

2017 2016 2016 2015 2014 ConsolidatedStatementofOperationsData

Revenues $ 2,415 $ 1,389 $ 2,272 $ 2,776 $ 4,063 $ 4,565Operatingexpenses Contractdrilling(exclusiveofdepreciation) 1,411 855 1,012 1,301 1,870 2,077

Lossonimpairment 59 — — — 2,746 4,219Depreciation 474 326 335 445 572 538Generalandadministrative 168 87 76 101 118 132

Operatingincome(loss) 303 121 849 929 (1,243) (2,401)

Otherincome(expense),net (180) (151) 114 68 (228) (148)Incometaxexpense(benefit) 82 67 105 108 (14) 141Income(loss)fromcontinuingoperations 41 (97) 858 889 (1,457) (2,690)

Income(loss)fromdiscontinuedoperations,net(1) 10 — (2) 8 (129) (1,199)

Netincome(loss) 51 (97) 856 897 (1,586) (3,889)Netincome(loss)attributabletononcontrollinginterests 1 (1) 5 7 9 14

Netincome(loss)attributabletoEnsco $ 50 $ (96) $ 851 $ 890 (1,595) (3,903)

ConsolidatedBalanceSheetandCashFlowStatementData

Workingcapital $ 1,216 $ 1,973 $ 1,876 $ 2,425 $ 1,510 $ 1,789Totalassets 14,781 13,683 13,602 14,375 13,611 16,023Long-termdebt,netofcurrentportion 4,748 4,748 4,677 4,943 5,869 5,868

Enscoshareholders'equity 9,082 8,165 7,973 8,251 6,513 8,215Cashflowsfromoperatingactivitiesofcontinuingoperations — 220 995 1,077 1,698 2,058

OtherFinancialData AdjustedEBITDA(2) $ 769 $ 400 $ 1,070 $ 1,233 $ 1,912 $ 2,232

(1) SeeNote10toourconsolidatedfinancialstatementsincludedin"Item8.FinancialStatementsandSupplementaryData"ofourForm10-Kforinformationondiscontinuedoperations.

(2) EnscodefinesAdjustedEBITDAasnetincome(loss)beforeincome(loss)fromdiscontinuedoperations,otherincome(expense),interestexpense,incometaxexpense(benefit),depreciation,amortization,lossonimpairment,(gain)lossonassetdisposalsandtransactioncosts.See"Non-GAAPFinancialMeasures."

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ThefollowingtablereconcilesEnsco'snetincome(loss)toAdjustedEBITDA.

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TwelveMonthsEndedSeptember30,

2017

NineMonthsEnded

September30,

YearEndedDecember31,

ProFormaCombined

2017 2016 2016 2015 2014 Netincome(loss) $ 51 $ (97) $ 856 $ 897 $ (1,586) $ (3,889)Less: Income(loss)fromdiscontinuedoperations,netoftax 10 — (2) 8 (129) (1,199)Income(loss)fromcontinuingoperations 41 (97) 858 889 (1,457) (2,690)

Add: Incometaxexpense(benefit) 82 67 105 108 (14) 141Interestexpense 200 167 172 229 216 161Other(income)expense (20) (16) (286) (297) 12 (13)Operatingincome(loss) 303 121 849 929 (1,243) (2,401)

Add: Depreciationexpense 474 326 335 445 572 538Amortization,net(1) (80) (56) (114) (140) (165) (115)Lossonimpairment 59 — — — 2,746 4,219(Gain)/lossonassetdisposals (2) (1) — (1) 2 (9)Transactioncosts 15 10 — — — —AdjustedEBITDA $ 769 $ 400 $ 1,070 $ 1,233 $ 1,912 $ 2,232

(1) Amortization,net,includesamortizationduringtheindicatedperiodfordeferredmobilizationrevenuesandcosts,deferredcapitalupgraderevenues,intangibleamortizationandotheramortization.

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RISKFACTORS

Beforepurchasinganynotesofferedhereby,youshouldconsidercarefullytherisksanduncertaintiesdescribedbelowandinItem1A"RiskFactors"inourForm10-KandoursubsequentlyfiledquarterlyreportsonForm10-Q,respectively,togetherwithalloftheotherinformationincludedorincorporatedbyreferenceinthisprospectussupplementandtheprospectus.Ifanyofthedescribedrisksactuallyweretooccur,ourbusiness,financialcondition,resultsofoperationsorgrowthprospectscouldbeaffectedmateriallyandadversely.Inthatcase,ourabilitytofulfillourobligationsunderthenotescouldbemateriallyaffected,andyoucouldloseallorpartofyourinvestment.Therisksdescribedbelowandinthedocumentswehaveincorporatedbyreferencearenottheonlyonesthatweface.Additionalrisksnotpresentlyknowntousorthatwecurrentlydeemimmaterialindividuallyorintheaggregatemayalsoimpairourbusinessoperations.

Thisprospectussupplementandthedocumentswehaveincorporatedbyreferencealsocontainforward-lookingstatementsthatinvolverisksanduncertainties.Ouractualresultscoulddiffermateriallyfromthoseanticipatedintheseforward-lookingstatementsasaresultofvariousfactors,includingtherisksanduncertaintiesfacedbyusdescribedbeloworincorporatedbyreferenceintothisprospectussupplement.

Recentlyapprovedtaxreformsmayhaveanadverseimpactonourbusinessorholdersofthenotes.

OnDecember20,2017,Congresspassed(andthePresidentsubsequentlysigned)anextensiveoverhauloftheU.S.federaltaxcode(the"TaxLegislation").TheTaxLegislationmakessignificantchangestothetaxationofindividualsandcorporations,whichcouldsignificantlyaffectourbusiness,operations,financialconditionandresultsofoperations,andmayhaveanadverseimpactoninvestorsintheNotes.PotentialinvestorsshouldconsulttheirtaxadvisorsabouttheTaxLegislationanditspotentialimpactonmakinganinvestmentintheNotes.

WeareevaluatingtheimpacttousoftheTaxLegislation.Wecurrentlyexpecttoincuraone-timetaxexpenseinthefourthquarterof2017,whichmaybematerial.However,wehavenotcompletedourevaluation,andtheultimateamountofthetaxexpensewillbebaseduponanumberoffactors,includingcompletionofourconsolidatedfinancialstatementsasofandfortheyearendedDecember31,2017andcompletionofour2017taxreturns.

Wemayincurimpairmentsasaresultofdeclinesindemandforoffshoredrillingrigs.

Weevaluatethecarryingvalueofourpropertyandequipment,primarilyourdrillingrigs,wheneventsorchangesincircumstancesindicatethatthecarryingvalueofsuchrigsmaynotberecoverable.Wehaveinthepastrecordedmaterialimpairmentsoflong-livedassetsandgoodwill.Weareevaluatingthecarryingvalueofourpropertyandequipmentinconnectionwiththepreparationofourannualfinancialstatements.Asaresultofthisevaluation,wemayrecordimpairments,whichmaybematerial,forthefourthquarterof2017.

ThenoteswillbestructurallysubordinatedtoallindebtednessandotherliabilitiesofoursubsidiariesandeffectivelysubordinatedtoclaimsbysecuredcreditorsofEnsco.

Weareaholdingcompanywhoseassetsconsistofdirectandindirectownershipinterestsin,andwhosebusinessisconductedthrough,subsidiaries.Consequently,ourabilitytorepayourdebt,includingthenotes,dependsprimarilyuponourreceiptoffundsfromoursubsidiariesthroughdividends,repaymentofintercompanynotesorotherpayments.Theabilityofoursubsidiariestopaydividends,repayintercompanynotesormakeotheradvances

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tousissubjecttorestrictionsimposedbyapplicablelaws,taxconsiderationsandthetermsofagreementsgoverningoursubsidiaries.Ournon-U.S.subsidiariesinparticularmaybesubjecttocurrencycontrols,repatriationrestrictions,withholdingobligationsonpaymentstous,andotherlimitations.

ThenoteswillbeobligationssolelyofEnscoandwillnotbeguaranteedbyanyofoursubsidiaries.Thenoteswillbestructurallysubordinatedtoanyandallexistingandfutureindebtedness,whetherornotsecured,andotherliabilitiesofoursubsidiaries,includingtheguaranteesbythesubsidiaryguarantorsunderourCreditFacility.Oursubsidiarieshavenoobligationtopayanyamountsdueonourdebtsecurities,includingthenotes,ortoprovideuswithfundsforourpaymentobligations.Theindenturegoverningthenoteswillnotlimittheabilityofoursubsidiariestoincurunsecuredindebtedness.AnyrightthatEnscohastoreceiveanyassetsofanyofthesubsidiariesupontheliquidationorreorganizationofthosesubsidiaries,andtheconsequentrightsofholdersofnotestorealizeproceedsfromthesaleofanyofthosesubsidiaries'assets,willbesubordinatedtotheclaimsofthosesubsidiaries'creditors,includingtradecreditorsandholdersofpreferredequityinterestsofthosesubsidiaries.TheindenturegoverningthenoteswillnotrestricttheabilityofoursubsidiariestoenterintoagreementsorotherarrangementsthathavetheeffectofprohibitingorrestrictingtheirabilitytopaydividendsorotherwisemakedistributionstoEnsco.Inaddition,thenoteswillbeeffectivelysubordinatedtoclaimsbyanysecuredcreditorsEnscomayhavetotheextentofthevalueoftheassetssecuringsuchclaims.Theindenturegoverningthenoteswillpermitustoincurasubstantialamountofsecuredindebtedness.AsofSeptember30,2017,(i)Enscoanditssubsidiarieshadoutstanding$4,882.7millionofconsolidatedindebtedness(including$958.1millionofrepurchasenotesoutstandingsubjecttothetenderoffers),(ii)Ensco'ssubsidiarieshadapproximately$1,987.9millionofindebtedness(consistingof$988.4million($688.4millionofwhicharerepurchasenotessubjecttothetenderoffers)issuedbyPride,$849.5millionissuedbyEnscoJerseyFinanceLimitedand$150.0millionissuedbyENSCOInternationalIncorporated),allofwhichwouldhavebeenguaranteedbyEnscoplc,and(iii)noneofEnscooritssubsidiarieshadanysecuredindebtedness.NeitherPridenorEnscoJerseyFinanceLimitedhasmaterialassetsoroperations.

Oursubstantialindebtednesscouldadverselyaffectourfinancialhealthandpreventusfromfulfillingourobligationsunderthenotes.

Wehaveasubstantialamountofindebtedness.AsofSeptember30,2017(withoutgivingeffecttothisoffering),wehadtotalindebtednessof$4,882.7million,andwehad$2.0billionoftotaladditionalborrowingcapacityunderourrevolvingcreditfacility.

Ourabilitytomakescheduledpaymentsofprincipalof,topaytheinterestorpremium,ifany,on,ortorefinanceourindebtedness(includingthenotes),ortofundcapitalexpenditures,acquisitionsandotherstrategicinitiativeswilldependonourfutureperformance,which,toacertainextent,issubjecttogeneraleconomic,financial,competitive,regulatoryandotherfactorsthatarebeyondourcontrol.Wecannotassureyouthatourbusinesswillgeneratesufficientcashflowfromoperationsorthatfutureborrowingswillbeavailableunderourrevolvingcreditfacilityorotherwiseinanamountsufficienttoenableustoserviceourindebtedness,includingthenotes,ortofundourotherliquidityneeds.Furthermore,ourleveragecouldadverselyaffectourbusiness.Inparticular,itcouldmakeusvulnerabletosustained,adversemacroeconomicweakness,limitourabilitytoobtainfurtherfinancing,limitourabilitytopursuecertainoperationalandstrategicopportunities,reduceourflexibilitytorespondtochangingbusinessandeconomicconditionsandincreaseborrowingcosts.

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Theprotectionsprovidedintheindentureandthenotesarelimited,andwemaytakeactionsthatcouldadverselyaffectthenotes.

Theindenturegoverningthenotescontainslimitedcovenants,includingthoserestrictingourabilityandoursubsidiaries'abilitytocreatecertainliensandenterintocertainsaleandleasebacktransactions.Theindenturewillnotrestrictourabilitytoengagein,ortootherwisebeapartyto,avarietyofothercorporatetransactions,circumstancesandeventsthatcouldhaveanadverseimpactonyourinvestmentinthenotes.Thelimitedcovenantscontainedintheindentureandthenoteswouldnotnecessarilyaffordholdersofthenotesprotectionintheeventofahighlyleveragedorothertransactioninvolvingusthatmayadverselyaffectsuchholders,includingbyincreasingtheamountofourindebtednessoutstandingatsuchtimeorotherwiseaffectingourcapitalstructure.Inaddition,thelimitationonliensandlimitationonsaleandleasebackcovenantscontainexceptionsthatwillallowusandoursubsidiariestoincurlienswithrespecttomaterialassets.See"DescriptionofNotes—RestrictiveCovenants."Inlightoftheseexceptions,holdersofthenotesmaybestructurallyorcontractuallysubordinatedtonewlenders.

Wemaynotbeabletorepurchasethenotesuponachangeofcontrol.

UponaChangeofControlTriggeringEvent,asdefinedunder"DescriptionofNotes—ChangeofControlOffer,"wewouldberequiredtooffertorepurchasealloranypartofthenotesthenoutstandingatapriceequalto101%oftheaggregateprincipalamountofthenotestoberepurchased,plusaccruedandunpaidinterest,ifany,subjecttocertainexceptions,unlesswehaveexercisedouroptiontoredeemthenotesinwhole.Ifweexperienceachangeofcontroltriggeringevent,therecanbenoassurancethatwewouldhavesufficientfinancialresourcesavailabletosatisfyourobligationstorepurchasethenotes.Inordertoobtainsufficientfundstopaythepurchasepriceoftheoutstandingnotes,weexpectthatwewouldhavetorefinancethenotes.Wecannotassureyouthatwewouldbeabletorefinancethenotesonfavorableterms,ifatall.Ourfailuretooffertopurchasealloutstandingnotesortopurchaseallvalidlytenderednoteswouldbeaneventofdefaultundertheindenturegoverningthenotes.Suchaneventofdefaultmayresultindefaultsandaccelerationofourotherindebtedness.Ourfutureindebtednessmayalsocontainrestrictionsonrepaymentrequirementswithrespecttospecifiedeventsortransactionsthatconstituteachangeofcontroltriggeringeventundertheindenture.See"DescriptionofNotes—ChangeofControlOffer."

Certainimportantcorporateevents,suchastakeovers,recapitalizations,restructurings,mergers,assetsalesorsimilartransactions,maynotconstituteaChangeofControlundertheindenturegoverningthenotesor,eveniftheydoconstituteaChangeofControl,maynotresultinaRatingDeclinewithin90daysfollowingconsummationthereof,andthuswouldnotpermittheholdersofthenotestorequireustorepurchasethenotes.Inaddition,thedefinitionofChangeofControlintheindenturegoverningthenotesincludesaphraserelatingtothedirectorindirectsale,transfer,conveyanceorotherdispositionof"allorsubstantiallyall"ofourassets.Althoughthereisalimitedbodyofcaselawinterpretingthephrase"substantiallyall,"thereisnopreciseestablisheddefinitionofthephraseunderapplicablelaw.Accordingly,theabilityofaholderofnotestorequireustorepurchaseitsnotesasaresultofasale,transfer,conveyanceorotherdispositionoflessthanallofourassetstoanotherpersonorgroupmaybeuncertain.

Activetradingmarketsmaynotdeveloporbemaintainedforthenotes.

Thenotesareanewissueofsecuritiesandthereisnopublictradingmarketforthenotes.WeintendtoapplyforthelistingofthenotesontheNYSE;however,wecangivenoassurancesthatthesenoteswillbesolisted.Theunderwritershaveinformedusthatthey

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intendtomakeamarketinthenotes.However,theunderwritersmayceasetheirmarket-makingatanytime.Theliquidityofthetradingmarketsinthenotesandthemarketpricesquotedforthenotesmaybeadverselyaffectedbychangesintheoverallmarketfordebtsecuritiesandbychangesinourfinancialperformanceorprospectsorintheprospectsforcompaniesinourindustrygenerally.Asaconsequence,anactivetradingmarketmaynotdeveloporbemaintainedforyournotes,youmaynotbeabletosellyournotes,or,evenifyoucansellyournotes,youmaynotbeabletosellthematanacceptableprice.

Wecouldenterintovarioustransactionsthatcouldincreasetheamountofouroutstandingdebt,adverselyaffectourcapitalstructureorcreditratingsorotherwiseadverselyaffectholdersofthenotes.

Thetermsofthenotesdonotpreventusfromenteringintoavarietyofacquisition,change-of-control,refinancing,recapitalizationorotherhighlyleveragedtransactions.Asaresult,wecouldenterintoavarietyoftransactionsthatcouldincreasethetotalamountofouroutstandingindebtedness,adverselyaffectourcapitalstructureorcreditratingsorotherwiseadverselyaffecttheholdersofthenotes.

Ourdebtratingshavebeendowngradedrecently.Anyadverseratingofthenotesmaycausetheirtradingpricetofall.

Moody'sInvestorServices,Inc.andS&PGlobalRatingsdowngradedourcreditratinginOctober2017.Bothratingagenciesperiodicallyreviewourcreditratingsaswellastheoffshoredrillingsectormoregenerally,andhavedowngradedotheroffshoredrillingcompaniesbasedonconcernsaboutgeneralindustryconditions.Therecanbenoassurancethatwewillbeabletomaintainourcreditratings,andiftherearefurtherdowngradesofourcreditrating,ornoticesofpotentialdowngrades,thetradingpricesofthenotescoulddecline.

Investorenforcementofciviljudgmentsagainstusmaybemoredifficult.

BecauseweareapubliclimitedcompanyincorporatedunderEnglishlaw,investorscouldexperiencemoredifficultyenforcingjudgmentsobtainedagainstusinU.S.courtsthanwouldbeobtainedagainstaU.S.company.Inaddition,itmaybemoredifficult(orimpossible)tobringsometypesofclaimsagainstusincourtsinEnglandthanitwouldbetobringsimilarclaimsagainstaU.S.companyinaU.S.court.

Redemptionorrepurchasemayadverselyaffectyourreturnonthenotes.

Thenotesareredeemableatanytimeatouroption,andthereforewemaychoosetoredeemsomeorallofthenotes,includingattimeswhenprevailinginterestratesarerelativelylow.Inaddition,wemayredeemthenotesatanytimeifduetocertainchangesintaxlawswearerequiredtowithholdtaxesonpaymentsonthenotesandpayadditionalamountswithrespectthereto.See"DescriptionofNotes—OptionalRedemption"and"DescriptionofNotes—RedemptionforChangesinTaxes."Further,ifachangeofcontroltriggeringeventoccurs,unlesswehaveexercisedouroptiontoredeemthenotes,wewillberequired,subjecttocertainexceptions,tomakeanoffertoeachholderofnotestorepurchasealloranypartofthatholder'snotesforcashequalto101%oftheprincipalamountofthenotestoberepurchased,plusaccruedandunpaidinterest,ifany,onthosenotestotherepurchasedate,asdescribedunder"DescriptionofNotes—ChangeofControlOffer."Anysuchredemptionorrepurchasemayoccuratatimewhenyoumaynotbeabletoreinvesttheredemptionorrepurchaseproceedsinacomparablesecurityataneffectiveinterestrateashighasthatbornebythenotes.

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USEOFPROCEEDS

Weestimatethatthenetproceedsfromthesaleofthenoteswillbeapproximately$afterdeductingtheunderwritingdiscountandestimatedofferingexpensespayablebyus.Weintendtousethenetproceedsfromthisofferingtofundthepurchaseprice,includinganyapplicabletenderpremium,payablewithrespecttotherepurchasenotesinthetenderoffers,aswellasforgeneralcorporatepurposes.Generalcorporatepurposesmayincluderepaymentofdebt,acquisitions,additionstoworkingcapital,capitalexpendituresandinvestmentsinoursubsidiaries.Outstandingnotessurrenderedinthetenderofferswillberetiredandcancelledandwillnotbereissued.See"Summary—ConcurrentTenderOffers."

The2019noteshaveafixedinterestrateof8.50%perannumandmatureonJune15,2019.The2020noteshaveafixedinterestrateof6.875%perannumandmatureonAugust15,2020.The2021noteshaveafixedinterestrateof4.70%perannumandmatureonMarch15,2021.

Certainoftheunderwritersandtheirrespectiveaffiliatesmayholdpositionsinouroutstandingnotes,includingtherepurchasenotes,andthereforemayreceiveaportionofthenetproceedsfromthisofferingifweredeemanyofthosenotesorpurchaseanyoftherepurchasenotespursuanttothetenderoffers.

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CAPITALIZATION

Thefollowingtablesetsforthourcashandcashequivalents,short-terminvestmentsandcapitalizationasofSeptember30,2017:

• onanactualbasis;and

• onanasadjustedbasistogiveeffectto(i)theissuanceandsaleof$500millionaggregateprincipalamountofnotesinthisofferingand(ii)theuseofnetproceedsfromthisoffering,beforeestimatedofferingexpensespayablebyus,assetforthunder"UseofProceeds,"assumingamaximumaggregatepurchasepriceoftherepurchasenotesof$492.5millionandparticipationbytheholdersof100%oftheaggregateprincipalamountofthe2019notes,40%oftheaggregateprincipalamountofthe2020notesand15%oftheaggregateprincipalamountofthe2021notes(ineachcasewiththeapplicableearlytenderpremium).

Thisofferingisnotconditionedontheconsummationofthetenderoffersorthetenderofanyspecifiedamountofrepurchasenotesinthetenderoffers.Therecanbenoassurancethatwewillconsummatethetenderoffers,whicharesubjecttomarketconditionsandotherfactors.Ifthetenderoffersarenotconsummatedorthenetproceedsfromthisofferingexceedthetotalconsiderationpayableinthetenderoffers,weintendtousetheremainingnetproceedsfromthisofferingforgeneralcorporatepurposes,whichmayincluderepaymentofdebt,acquisitions,additionstoworkingcapital,capitalexpendituresandinvestmentsinoursubsidiaries.Suchuseofthenetproceedsofthisofferingisnotreflectedinthefollowingtable.

Youshouldreadthistableinconjunctionwithourhistoricalfinancialstatementsandnotesthatareincorporatedbyreferenceintothisprospectussupplementandtheaccompanyingprospectusforadditionalinformationaboutourcapitalstructure.Thecapitalizationtablebelowisnotnecessarilyindicativeofourfuturecapitalizationorfinancialcondition.

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AsofSeptember30,2017 Actual(1) AsAdjusted (Inmillions) Cashandcashequivalents(2) $ 724.4 $ 724.4Short-terminvestments(2) 1,069.8 1,069.8Debt,includingcurrentmaturities: Revolvingcreditfacility(3) — —8.50%SeniorNotesdue2019(4) 237.5 —6.875%SeniorNotesdue2020(4) 450.9 270.53.00%ExchangeableSeniorNotesdue2024(5) 849.5 849.57.20%Debenturesdue2027(6) 150.0 150.07.875%SeniorNotesdue2040(4) 300.0 300.04.70%SeniorNotesdue2021 269.7 229.94.50%SeniorNotesdue2024 623.3 623.38.00%SeniorNotesdue2024 332.0 332.05.20%SeniorNotesdue2025 669.3 669.35.75%SeniorNotesdue2044 1,000.5 1,000.5%SeniorNotesdue2026offeredhereby — 500.0

Totaldebt 4,882.7 4,925.0Totalequity 8,167.3 8,167.3Totalcapitalization $ 13,050.0 $ 13,092.3

(1) Thedebtfiguresbelowrepresenttheprincipalamountoutstandingforeachrespectiveinstrumentandthereforedifferfromtheircarryingamountsreflectedinourfinancialstatementsduetotheexclusionofcertainunamortizeddeferredfinancingcosts,discountsandpremiums.

(2) AsofDecember31,2017,ourcombinedcashandcashequivalentandshort-terminvestmentbalancewas$889million.Additionally,onJanuary5,2018,wemadeapaymentof$208millionwhichcomprisesthesubstantialmajorityoftheremainingshipyardpaymentsforENSCO123.

(3) AsofSeptember30,2017,therewerenoborrowingsorlettersofcreditoutstandingunderour$2.0billionrevolvingcreditfacility.

(4) IssuedbyPride,awhollyownedsubsidiarywithnomaterialassetsoroperations,andguaranteedbyEnscoplc.

(5) Ourexchangeableseniornotesdue2024wereissuedbyoursubsidiaryEnscoJerseyFinanceLimited,aJerseyIslandscompany,andguaranteedbyEnscoplc.

(6) IssuedbyENSCOInternationalIncorporated,awhollyownedsubsidiary,andguaranteedbyEnscoplc.

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DESCRIPTIONOFNOTES

Wehavesummarizedselectedprovisionsofthenotesbelow.Wewillissuethenotesundertheindenture,datedasofMarch17,2011(the"baseindenture"),betweenusandDeutscheBankTrustCompanyAmericas,astrustee,assupplementedbyafifthsupplementalindentureestablishingthetermsofthenotes.Whenwerefertothe"indenture"wemeanthebaseindentureassupplementedbythefifthsupplementalindenture.ThetermsofthenotesincludethosestatedintheindentureandthosemadepartoftheindenturebyreferencetotheTrustIndentureActof1939,asamended(the"TrustIndentureAct").

Thenoteswillbeaseparateseriesofseniordebtsecuritiesundertheindenture.Weurgeyoutoreadthebaseindentureandrelatedsupplementalindenturebecausethey,andnotthisdescription,defineyourrightsasholdersofthenotes.Copiesofthebaseindentureandrelatedsupplementalindentureareavailableassetforthunderthecaption"WhereYouCanFindMoreInformation;IncorporationbyReference."Our4.70%SeniorNotesdue2021,5.20%SeniorNotesdue2025,4.50%SeniorNotesdue2024,8.00%SeniorNotesdue2024and5.75%SeniorNotesdue2044arecurrentlyoutstandingunderthebaseindenture.

Asusedinthis"DescriptionofNotes"section,referencesto"Ensco,""we,""our"or"us"refersolelytoEnscoplcandnottoanyofitsSubsidiaries.Inaddition,wehaveusedinthisdescriptioncapitalizedandothertermsthatwehavedefinedbelowunder"—Definitions"andinotherpartsofthisdescription.

General

Thenoteswillmatureon,2026andwillbearinterestat%peryear.InterestonthenoteswillaccruefromtheIssueDate.Wewillpayinterestsemi-annuallyonandofeachyear,commencingon,2018andwillpayinteresttothepersoninwhosenameanoteisregisteredatthecloseofbusinessontheorprecedingtheinterestpaymentdate.Wewillcomputeinterestonthebasisofa360-dayyearconsistingoftwelve30-daymonths,willmakepaymentsonthenotesattheofficesofthetrusteeandanypayingagentandmaymakepaymentsbywiretransferforthenotesheldinbook-entryformorbycheckmailedtotheaddressofthepersonentitledtothepaymentasitappearsinthenoteregister.

Wewillissuethenotesonlyinfullyregisteredform,withoutcoupons,inminimumdenominationsof$2,000andanyintegralmultiplesof$1,000abovethatamount.

Wemay"reopen"thenotesandissueanunlimitedprincipalamountofadditionalnotesinthefuturewithouttheconsentoftheholders,providedthatsuchadditionalnoteswillnothavethesameCUSIP,ISINorotheridentifyingnumbersastheoutstandingnotesunlesssuchadditionalnotesarefungiblewiththeoutstandingnotesforU.S.federalincometaxpurposes.

OptionalRedemption

Wemayredeemthenotes,inwholeatanytimeorinpartfromtimetotime,priortotheirmaturity.IfweelecttoredeemthenotesbeforetheParCallDate,wewillpayaredemptionpriceequaltothegreaterof:

(1) 100%oftheprincipalamountofthenotestoberedeemed;and

(2) thesumofthepresentvaluesoftheremainingscheduledpaymentsofprincipalandinterestthereonthatwouldbedueifthenotesmaturedontheParCallDate(notincludinganyportionofsuchpaymentsofinterestaccruedasofthedateofredemption),discountedtothedateofredemptiononasemi-annualbasis(assuming

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a360-dayyearconsistingoftwelve30-daymonths)attheTreasuryRate(asdefinedbelow)plus50basispoints,plusaccruedinterestthereontothedateofredemption.

IfweelecttoredeemthenotesonoraftertheParCallDate,wewillpayanamountequalto100%oftheprincipalamountofthenotesredeemedplusaccruedinterestthereontothedateofredemption.

Notwithstandingtheforegoing,installmentsofinterestonthenotesbeingredeemedthataredueandpayableoninterestpaymentdatesfallingonorpriortoaredemptiondatewillbepayableontheinterestpaymentdatetotheregisteredholdersasofthecloseofbusinessontherelevantrecorddateofthenotesandtheindenture.

"ComparableTreasuryIssue"meanstheUnitedStatesTreasurysecurityselectedbytheQuotationAgentashavingamaturitycomparabletotheremainingtermofthenotes(assuming,forthispurpose,thatsuchnotesmaturedontheParCallDate)toberedeemedthatwouldbeutilized,atthetimeofselectionandinaccordancewithcustomaryfinancialpractice,inpricingnewissuesofcorporatedebtsecuritiesofcomparablematuritytotheremainingtermofsuchnotes.

"ComparableTreasuryPrice"means,withrespecttoanyredemptiondate,(i)theaverageoftwoReferenceTreasuryDealerQuotationsforsuchredemptiondate,afterexcludingthehighestandlowestsuchReferenceTreasuryDealerQuotations,or(ii)ifwearegivenfewerthanfoursuchReferenceTreasuryDealerQuotations,theaverageofallsuchquotations,or(iii)ifonlyoneReferenceTreasuryDealerQuotationisreceived,suchquotation.

"ParCallDate"means(threemonthspriortothematuritydateofthenotes).

"QuotationAgent"meanstheReferenceTreasuryDealerappointedbyus.

"ReferenceTreasuryDealer"meanseachofDeutscheBankSecuritiesInc.andCitigroupGlobalMarketsInc.(ortheirrespectiveaffiliatesthatarePrimaryTreasuryDealers(asdefinedbelow))andtheirrespectivesuccessorsandtwoothernationallyrecognizedinvestmentbankingfirmsthatarePrimaryTreasuryDealersspecifiedfromtimetotimebyus;provided,however,thatifanyoftheforegoingshallceasetobeaprimaryU.S.GovernmentsecuritiesdealerinNewYorkCity(a"PrimaryTreasuryDealer"),wewillsubstitutethereforanotherPrimaryTreasuryDealer.

"ReferenceTreasuryDealerQuotations"means,withrespecttoeachReferenceTreasuryDealerandanyredemptiondate,theaverage,asdeterminedbyus,ofthebidandaskedpricesfortheComparableTreasuryIssue(expressedineachcaseasapercentageofitsprincipalamount)quotedinwritingtousbysuchReferenceTreasuryDealerat5:00p.m.,NewYorkCitytime,onthethirdbusinessdayprecedingsuchredemptiondate.

"TreasuryRate"means,withrespecttoanyredemptiondate,therateperannumequaltothesemi-annualequivalentyieldtomaturityoftheComparableTreasuryIssue,assumingapricefortheComparableTreasuryIssue(expressedasapercentageofitsprincipalamount)equaltotheComparableTreasuryPriceforsuchredemptiondate.

Noticeofanyredemptiondescribedunder"—OptionalRedemption"willbemailedatleast15days,butnotmorethan60days,beforetheredemptiondatetoeachholder(withacopytothetrustee)ofthenotestoberedeemed.Unlesswedefaultinpaymentoftheredemptionprice,onandaftertheredemptiondate,interestwillceasetoaccrueonthenotesorportionsthereofcalledforredemption.Iflessthanallofthenotesaretoberedeemed,thenotestoberedeemedshallbeselectedbylotbyDTC,inthecaseofnotesrepresentedbyaglobalsecurity,orbythetrusteebyamethodthetrusteedeemstobefairandappropriate

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andinaccordancewithanyapplicableproceduresofDTC,inthecaseofnotesthatarenotrepresentedbyaglobalsecurity.

Wemayatanytimepurchasenotesontheopenmarketorotherwiseatanyprice.Wewillsurrenderallnotesthatweredeemorpurchasetothetrusteeforcancellation.Wemaynotreissueorresellanyofthesenotes.

ChangeofControlOffer

IfaChangeofControlTriggeringEventoccurs,unlesswehaveexercisedouroptiontoredeemthenotesasdescribedaboveunder"—OptionalRedemption,"wewillberequiredtomakeanoffer(the"changeofcontroloffer")toeachholderofnotestorepurchasealloranypartofthatholder'snotesonthetermssetforthinthenotes.Inthechangeofcontroloffer,wewillberequiredtoofferpaymentincashequalto101%oftheprincipalamountofthenotestoberepurchased,plusaccruedandunpaidinterest,ifany,onthosenotestotherepurchasedate(the"changeofcontrolpayment"),subjecttotherightsofholdersofthenotesonaregularrecorddatetoreceiveinterestdueontherelatedinterestpaymentdatefallingonorpriortotherepurchasedate.

Within30daysfollowinganyChangeofControlTriggeringEventor,atouroption,priortoanyChangeofControl,butafterpublicannouncementofthetransactionthatconstitutesormayconstitutetheChangeofControl,wewillmailanoticetoholdersofthenotes,withacopytothetrustee,describingthetransactionthatconstitutesormayconstitutetheChangeofControlTriggeringEventandofferingtorepurchasethenotesonthedatespecifiedinthenotice,whichdatewillbenoearlierthan30daysandnolaterthan60daysfromthedatesuchnoticeismailed(the"changeofcontrolpaymentdate").Thenotice,ifmailedpriortothedateofconsummationoftheChangeofControl,willstatethattheoffertopurchaseisconditionedontheChangeofControlTriggeringEventoccurringonorpriortothechangeofcontrolpaymentdate.Intheeventthatsuchoffertopurchasefailstosatisfytheconditionintheprecedingsentence,wewillcauseanothernoticemeetingtheaforementionedrequirementstobemailedtoholdersofthenotes.

Onthechangeofcontrolpaymentdate,wewill,totheextentlawful:

• acceptforpaymentallnotesorportionsofnotesproperlytenderedpursuanttothechangeofcontroloffer;

• depositwiththepayingagentanamountequaltothechangeofcontrolpaymentinrespectofallnotesorportionsofnotesproperlytendered;and

• deliverorcausetobedeliveredtothetrusteethenotesproperlyacceptedtogetherwithanofficers'certificatestatingtheaggregateprincipalamountofnotesorportionsofnotesbeingrepurchased.

Thepayingagentwillpromptlytransmittoeachholderofproperlytenderednotesthechangeofcontrolpaymentforthenotesbeingrepurchased,andthetrusteewillpromptlyauthenticateandmail(orcausetobetransferredbybook-entry)toeachholderanewnoteequalinprincipalamounttoanyunrepurchasedportion,ifany,ofanynotessurrendered,providedthateachnewnotewillbeinaprincipalamountof$2,000oranintegralmultipleof$1,000inexcessthereof.

WewillnotberequiredtomakeachangeofcontrolofferupontheoccurrenceofaChangeofControlTriggeringEventifathirdpartymakessuchanofferinthemanner,atthetimesandotherwiseincompliancewiththerequirementsforanoffermadebyusandthethirdpartyrepurchasesallnotesproperlytenderedandnotwithdrawnunderitsoffer.In

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addition,wewillnotrepurchaseanynotesiftherehasoccurredandiscontinuingonthechangeofcontrolpaymentdateaneventofdefaultundertheindenture,otherthanadefaultinthepaymentofthechangeofcontrolpaymentuponaChangeofControlTriggeringEvent.

UpontheoccurrenceofaChangeofControlTriggeringEvent,wemaynothavesufficientfundstorepurchasethenotesintheamountofthechangeofcontrolpaymentincashatsuchtime.Inaddition,ourabilitytorepurchasethenotesforcashmaybelimitedbylaworthetermsofotheragreementsrelatingtoourindebtednessoutstandingatthetime.Thefailuretomakesuchrepurchasewouldresultinadefaultunderthenotes.

WewillcomplywiththerequirementsofRule14e-1undertheExchangeAct,andanyothersecuritieslawsandregulationsthereundertotheextentthoselawsandregulationsareapplicableinconnectionwiththerepurchaseofthenotesasaresultofaChangeofControlTriggeringEvent.Totheextentthattheprovisionsofanysuchsecuritieslawsorregulationsconflictwiththechangeofcontrolofferprovisionsofthenotes,wewillcomplywiththosesecuritieslawsandregulationsandwillnotbedeemedtohavebreachedourobligationsunderthechangeofcontrolofferprovisionsofthenotesbyvirtueofanysuchconflict.

Ranking

Thenoteswillconstituteourseniorunsecureddebtandwillrankequallyinrightofpaymentwithourseniorunsecureddebtfromtimetotimeoutstandingandseniorinrightofpaymenttoanyfuturesubordinateddebtfromtimetotimeoutstanding.Thenoteswillbeeffectivelyjuniortooursecureddebtfromtimetotimeoutstandingtotheextentofthevalueoftheassetssecuringthatdebt.

WeareaholdingcompanyanddonotconductanybusinessoperationsorhaveanysignificantassetsotherthaninterestsinourSubsidiaries.WecurrentlyconductouroperationsthroughbothU.S.andnon-U.S.Subsidiaries,andouroperatingincomeandcashflowaregeneratedbyourSubsidiaries.Asaresult,cashweobtainfromourSubsidiariesistheprincipalsourceoffundsnecessarytomeetourdebtserviceobligations.Contractualprovisionsorlaws,aswellasourSubsidiaries'financialconditionandoperatingrequirements,maylimitourabilitytoobtaincashfromourSubsidiariesthatwerequiretopayourdebtserviceobligations,includingpaymentsonthenotes.ThenoteswillbeobligationssolelyofusandwillnotbeguaranteedbyanyofourSubsidiaries.Therefore,holdersofthenoteswillhaveajuniorpositiontotheclaimsofcreditors,includingtradecreditorsandtortclaimants,ofourSubsidiarieswithrespecttotheirassetsandearnings.

AdditionalAmounts

Allpaymentsmadeunderorwithrespecttothenoteswillbemadefreeandclearofandwithoutwithholdingordeductionfor,oronaccountof,anypresentorfuturetax,duty,levy,impost,assessmentorothergovernmentalcharge(includingpenalties,interest,additionstotaxandotherliabilitiesrelatedthereto)(collectively,"Taxes")unlessthewithholdingordeductionofsuchTaxesisthenrequiredbylaw.Ifanydeductionorwithholdingfor,oronaccountof,anyTaxesimposedorleviedbyoronbehalfof(1)anyjurisdictioninwhichweareorganized,residentordoingbusinessforTaxpurposesoranydepartmentorpoliticalsubdivisionthereoforthereinor(2)anyjurisdictionfromorthroughwhichpaymentismadebyusorthepayingagentoranydepartmentorpoliticalsubdivisionthereofortherein(each,a"TaxJurisdiction")willatanytimeberequiredtobemadefromanypaymentsmadeunderorwithrespecttothenotes,includingpaymentsofprincipal,redemptionprice,interestorpremium,wewillpaysuchadditionalamounts(the"AdditionalAmounts")asmaybenecessaryinorderthatthenetamountsreceivedinrespectofsuchpaymentsbyeachholder

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aftersuchwithholdingordeduction(includinganysuchdeductionorwithholdinginrespectofAdditionalAmounts)willequaltherespectiveamountswhichwouldhavebeenreceivedinrespectofsuchpaymentsintheabsenceofsuchwithholdingordeduction;provided,however,thatnoAdditionalAmountswillbepayablewithrespectto:

(1) anyTaxes,totheextentsuchTaxeswouldnothavebeenimposedbutfortheexistenceofanypresentorformerconnectionbetweentheholderorthebeneficialownerofthenotesandtherelevantTaxJurisdiction(otherthananyconnectionarisingsolelyfromtheacquisition,ownership,holdingordispositionofthenotes,theenforcementofrightsunderthenotesand/orthereceiptofanypaymentsinrespectofthenotes);

(2) anyTaxes,totheextentsuchTaxeswouldnothavebeenimposedbutforthefailureoftheholderorthebeneficialownerofthenotestocomplywithanycertification,identification,information,documentation,orotherreportingrequirements,includinganapplicationforreliefunderanapplicabledoubleTaxtreaty,whetherrequiredbystatute,treaty,regulationoradministrativepracticeofaTaxJurisdiction,asapreconditiontoexemptionfrom,orreductionintherateofdeductionorwithholdingof,TaxesimposedbytheTaxJurisdiction(including,withoutlimitation,acertificationthattheholderorbeneficialownerisnotresidentintheTaxJurisdictionorisaresidentofanapplicableTaxtreatyjurisdiction),butineachcase,onlytotheextenttheholderorthebeneficialownerislegallyeligibletoprovidesuchcertificationordocumentation;provided,however,thatintheeventthatanysuchrequirementsareimposedasaresultofanamendmentto,orchangein,anylaws,Taxtreaties,regulationsorrulings(oranyofficialadministrativeorjudicialinterpretationthereof)aftertheIssueDate,thisparagraph(2)willapplyonlyifwenotifythetrustee,atleast30daysbeforeanysuchwithholdingordeductionwouldbepayable,thatholdersorbeneficialownersmustcomplywithsuchcertification,identification,information,documentationorotherreportingrequirements;

(3) anyTaxes,totheextentsuchTaxeswereimposedasaresultofthepresentationofanoteforpayment(wherepresentationisrequired)morethan30daysaftertherelevantpaymentisfirstmadeavailableforpaymenttotheholder(excepttotheextentthattheholderwouldhavebeenentitledtoAdditionalAmountshadthenotebeenpresentedonthelastdayofsuch30dayperiod);

(4) anyestate,inheritance,gift,transfer,personalpropertyorsimilarTax;

(5) anyTaxespayableotherwisethanbydeductionorwithholdingfrompaymentsmadeunderorwithrespecttothenotes;or

(6) anycombinationoftheaboveitems.

WealsowillnotpayanyAdditionalAmountstoanyholderwhoisafiduciaryorpartnershiporotherthanthesolebeneficialownerofthenotetotheextentthattheobligationtopayAdditionalAmountswouldbereducedoreliminatedbytransferringthenotesinquestiontothesolebeneficialowner,butonlyifthereisnomaterialcommercialorlegalimpedimentto,ormaterialcostassociatedwith,transferringthenotestothesolebeneficialowner.

Inadditiontotheforegoing,wewillalsopayandindemnifytheholderforanypresentorfuturestamp,stampduty,stampdutyreservetax,issue,registration,transfer,courtordocumentarytaxes,oranyotherexciseorpropertytaxes,chargesorsimilarlevies(includingpenalties,interest,additionstoTaxandotherliabilitiesrelatedthereto)whichareleviedbyanyTaxJurisdictionontheexecution,delivery,issuance,orregistrationofanyofthenotes,

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theindentureoranyotherdocumentorinstrumentreferredtotherein,orthereceiptofanypaymentswithrespectto,orenforcementof,thenotes.

IfwebecomeawarethatwewillbeobligatedtopayAdditionalAmountswithrespecttoanypaymentunderorwithrespecttothenotes,wewilldelivertothetrusteeonadatewhichisatleast30dayspriortothedateofthatpayment(unlesstheobligationtopayAdditionalAmountsarisesafterthe30thdaypriortothatpaymentdate,inwhichcaseweshallnotifythetrusteepromptlythereafter)noticestatingthefactthatAdditionalAmountswillbepayableandtheamountestimatedtobesopayable.ThenoticemustalsosetforthanyotherinformationreasonablynecessarytoenablethepayingagenttopayAdditionalAmountstoholdersontherelevantpaymentdate.WewillprovidethetrusteewithdocumentationreasonablysatisfactorytothetrusteeevidencingthepaymentofAdditionalAmounts.

WewilltimelymakeallwithholdingsanddeductionsrequiredbylawandwillremitthefullamountdeductedorwithheldtotherelevantTaxauthorityinaccordancewithapplicablelaw.Wewillfurnishtothetrustee(ortoaholderuponrequest),withinareasonabletimeafterthedatethepaymentofanyTaxessodeductedorwithheldismade,certifiedcopiesofTaxreceiptsevidencingpaymentbyus,orifreceiptsarenotreasonablyavailable,otherevidenceofpaymentreasonablysatisfactorytothetrustee.

Wheneverintheindentureorinthis"DescriptionofNotes"thereismentioned,inanycontext,thepaymentofamountsbasedupontheprincipalamountofthenotesorofprincipal,interestorofanyotheramountpayableunder,orwithrespectto,anyofthenotessuchmentionshallbedeemedtoincludethepaymenttothepayingagentofAdditionalAmounts,ifapplicable.

Theobligationsunderthissectionwillsurviveanytermination,defeasanceordischargeoftheindentureandwillapply,mutatismutandis,toanyjurisdictioninwhichanysuccessorPersontousisorganized,residentordoingbusinessforTaxpurposesoranyjurisdictionfromorthroughwhichsuchPersonoritspayingagentmakesanypaymentonthenotesand,ineachcase,anydepartmentorpoliticalsubdivisionthereofortherein.

RedemptionforChangesinTaxes

Wemayredeemthenotes,inwholebutnotinpart,atouroptionupongivingnotlessthan30normorethan60days'priorwrittennoticetothetrusteeandtheholders,ataredemptionpriceequalto100%oftheaggregateprincipalamountthereof,togetherwithaccruedandunpaidinterest,ifany,totheredemptiondateandallAdditionalAmounts,ifany,whichotherwisewouldbepayable,ifonthenextdateonwhichanyamountwouldbepayableinrespectofthenotes,wewouldberequiredtopayAdditionalAmounts,andwecannotavoidanysuchpaymentobligationbytakingreasonablemeasuresavailabletous,asaresultof:

(1) anyamendmentto,orchangein,thelaws,TaxtreatiesoranyregulationsorrulingspromulgatedthereunderofarelevantTaxJurisdictionwhichisannouncedandbecomeseffectiveafterthedateofthisprospectussupplement(or,iftheapplicableTaxJurisdictionbecameaTaxJurisdictiononadateafterthedateofthisprospectussupplement,suchlaterdate);or

(2) anyamendmentto,orchangein,anofficialinterpretationorapplicationregardingsuchlaws,Taxtreaties,regulationsorrulings,includingbyvirtueofaholding,judgmentororderbyacourtofcompetentjurisdictionwhichisannouncedandbecomeseffectiveafterthedateofthisprospectussupplement(or,iftheapplicable

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TaxJurisdictionbecameaTaxJurisdictiononadateafterthedateofthisprospectussupplement,suchlaterdate).

Wewillnotgiveanysuchnoticeofredemptionearlierthan90dayspriortotheearliestdateonwhichwewouldbeobligatedtopayAdditionalAmountsormorethan365daysaftertheapplicablelawchangetakeseffect,and,atthetimesuchnoticeisgiven,theobligationtopayAdditionalAmountsmustremainineffect.

RestrictiveCovenants

Limitation on Liens

Wewillnot,andwillnotpermitanyofourSubsidiariesto,incur,issueorassumeanyIndebtednessforborrowedmoneysecuredbyanyLienuponanyPrincipalPropertyoranysharesofstockorIndebtednessofanySubsidiarythatownsorleasesaPrincipalProperty(whethersuchPrincipalProperty,sharesofstockorIndebtednessarenowownedorhereafteracquired)withoutmakingeffectiveprovisionwherebythenotes(togetherwith,ifwesodetermine,anyotherIndebtednessorotherobligationofusoranySubsidiary)shallbesecuredequallyandratablywith(or,atouroption,priorto)theIndebtednesssosecuredbyaLienonthesameassetsofusorsuchSubsidiary,asthecasemaybe,forsolongassuchIndebtednessissosecured.Theforegoingrestrictionswillnot,however,applytoIndebtednesssecuredbyPermittedLiens.

Notwithstandingtheforegoing,weandourSubsidiariesmay,withoutsecuringthenotes,incur,issueorassumeIndebtednessthatwouldotherwisebesubjecttotheforegoingrestrictionsinanaggregateprincipalamountthat,togetherwithallothersuchIndebtednessofusandourSubsidiariesthatwouldotherwisebesubjecttotheforegoingrestrictions(notincludingIndebtednesspermittedtobesecuredunderthedefinitionofPermittedLiens)andtheaggregateamountofAttributableIndebtednessdeemedoutstandingwithrespecttoSale/LeasebackTransactions(otherthanSale/LeasebackTransactionsinconnectionwithwhichwehavevoluntarilyretiredanyofthenotes,anyPariPassuIndebtednessoranyFundedIndebtednesspursuanttoclause(i)ofthethirdbulletbelowunder"LimitationonSaleLeasebackTransactions")doesnotatanyonetimeexceed15%ofConsolidatedNetTangibleAssets.

Forpurposesofthiscovenant,ifatthetimeanyIndebtednessisincurred,issuedorassumed,suchIndebtednessisunsecuredbutislatersecuredbyaLien,suchIndebtednessshallbedeemedtobeincurredatthetimethatsuchIndebtednessissosecuredbyaLien.

Limitation on Sale/Leaseback Transactions

Solongasthenotesareoutstanding,wewillnot,andwewillnotpermitanySubsidiaryto,sellortransfer(otherthantousoraWhollyOwnedSubsidiary)anyPrincipalProperty,whetherownedatthedateoftheindentureorthereafteracquired,whichhasbeeninfulloperationformorethan120dayspriortosuchsaleortransfer,withtheintentionofenteringintoaleaseofsuchPrincipalProperty(exceptforaleaseforaterm,includinganyrenewalthereof,ofnotmorethanthreeyears),ifaftergivingeffecttheretotheAttributableIndebtednessinrespectofallsuchsaleandleasebacktransactionsinvolvingPrincipalPropertiesshallbeinexcessof15%ofConsolidatedNetTangibleAssets.

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Notwithstandingtheforegoing,weoranySubsidiarymaysellanyPrincipalPropertyandleaseitbackifthenetproceedsofsuchsaleareatleastequaltothefairvalueofsuchpropertyasdeterminedbyourBoardofDirectorsand:

• weorsuchSubsidiarywouldbeentitledtoincurIndebtednessinaprincipalamountequaltotheAttributableIndebtednesswithrespecttosuchSale/LeasebackTransactionsecuredbyaLienonthepropertysubjecttosuchSale/LeasebackTransactionpursuanttothecovenantdescribedunder"LimitationonLiens"abovewithoutequallyandratablysecuringthenotespursuanttosuchcovenant;

• aftertheIssueDateandwithinaperiodcommencingninemonthspriortotheconsummationofsuchSale/LeasebackTransactionandendingninemonthsaftertheconsummationthereof,weorsuchSubsidiaryshallhaveexpendedforpropertyusedortobeusedintheordinarycourseofourbusinessandthatofourSubsidiariesanamountequaltoalloraportionofthenetproceedsofsuchSale/LeasebackTransactionandweshallhaveelectedtodesignatesuchamountasacreditagainstsuchSale/LeasebackTransaction(withanysuchamountnotbeingsodesignatedtobeappliedassetforthinthefollowingbulletorasotherwisepermitted);or

• we,duringthenine-monthperiodaftertheeffectivedateofsuchSale/LeasebackTransaction,shallhaveappliedtoeither(i)thevoluntarydefeasanceorretirementofanynotes,anyPariPassuIndebtednessoranyFundedIndebtednessor(ii)theacquisitionofoneormorePrincipalPropertiesatfairvalue,anamountequaltothegreaterofthenetproceedsofthesaleortransferofthepropertyleasedinsuchSale/LeasebackTransactionandthefairvalue,asdeterminedbyourBoardofDirectors,ofsuchpropertyasofthetimeofenteringintosuchSale/LeasebackTransaction(ineithercaseadjustedtoreflecttheremainingtermoftheleaseandanyamountexpendedbyusassetforthintheprecedingbullet),lessanamountequaltothesumoftheprincipalamountofnotes,PariPassuIndebtednessandFundedIndebtednessvoluntarilydefeasedorretiredbyusplusanyamountexpendedtoacquireanyPrincipalPropertiesatfairvalue,withinsuchninemonthperiodandnotdesignatedasacreditagainstanyotherSale/LeasebackTransactionenteredintobyusoranyofourSubsidiariesduringsuchperiod.

Consolidation, Merger and Sale of Assets

Wewillnot,directlyorindirectly,inanytransactionorseriesofrelatedtransactions:(1)consolidateormergewithorintoanotherPerson(whetherornotwearethesurvivingPerson);(2)sell,assign,transfer,conveyorotherwisedisposeofallorsubstantiallyallofourandourSubsidiaries'propertiesorassetstakenasawhole,or(3)assignanyofourobligationsunderthenotesandtheindenture,inoneormorerelatedtransactions,toanotherPerson;unless:

(i) either:(A)wearethesurvivingorcontinuingPerson;or(B)thePersonformedby,survivingorcontinuedbyanysuchconsolidation,amalgamationormerger(ifotherthanus)orthePersontowhichsuchsale,assignment,transfer,conveyanceorotherdispositionshallhavebeenmadeisanEntity,validlyorganizedandexistingingoodstanding(totheextenttheconceptofgoodstandingisapplicable)underthelawsofanystateoftheUnitedStates,theDistrictofColumbia,theCaymanIslands,Bermuda,Switzerland,theUnitedKingdom,theKingdomoftheNetherlands,theGrandDuchyofLuxembourg,Ireland,oranyothermembercountryoftheEuropeanUnion;

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(ii) thePersonformedby,survivingorcontinuedbyanysuchconsolidation,amalgamationormerger(ifotherthanus)orthePersontowhichsuchsale,assignment,transfer,conveyanceorotherdispositionshallhavebeenmadeassumesallourobligationsunderthenotesandtheindenture;

(iii) immediatelyaftersuchtransactionnoDefaultorEventofDefaultexists;and

(iv) weshallhavedeliveredtothetrusteeanOfficers'Certificateandanopinionofcounsel,eachstatingthatsuchmerger,consolidation,amalgamationorsale,assignment,transfer,conveyanceorotherdispositionofsuchpropertiesorassetsorassignmentofourobligationsunderthenotesandtheindentureandsuchsupplementalindenture,ifany,complywiththeindenture.

Wewillnot,directlyorindirectly,leaseallorsubstantiallyallofourpropertiesorassets,inoneormorerelatedtransactions,toanyotherPerson.

Notwithstandingtheforegoing,thelimitationsdescribedaboveshallnotapplytoasale,assignment,transfer,conveyanceorotherdispositionofassetsbetweenoramongusandanyofourWhollyOwnedSubsidiaries.

EventsofDefault

An"EventofDefault"onthenotesoccursif:

(1) wedefaultinthepaymentofinterestonanynotewhenthesamebecomesdueandpayableandtheDefaultcontinuesforaperiodof30days;

(2) wedefaultinthepaymentoftheprincipalofanynotewhenthesamebecomesdueandpayableatmaturity,uponredemptionorotherwise;

(3) wefailtocomplywithanyofourotheragreementsinthenotesortheindenture(astheyrelatethereto),whichshallnothavebeenremediedwithinthespecifiedperiodafterwrittennotice,asspecifiedbelow;

(4) wepursuanttoorwithinthemeaningofanyBankruptcyLawshall:

(a) commenceavoluntarycase,

(b) consenttotheentryofanorderforreliefagainstusinaninvoluntarycase,

(c) consenttotheappointmentofaCustodianofusforallorsubstantiallyallofthepropertyofus,or

(d) makeageneralassignmentforthebenefitofcreditors;or

(5) acourtofcompetentjurisdictionentersintoanorderordecreeunderanyBankruptcyLawthat:

(a) isforreliefagainstusinaninvoluntarycase,or

(b) appointsaCustodianofusorsubstantiallyallofthepropertyofus,or

(c) orderstheliquidationofus,

andtheorderordecreeremainsunstayedandineffectfor60days.

Theterm"BankruptcyLaw"meanstheBankruptcyActoranysimilarFederalorStatelawforthereliefofdebtors.Theterm"Custodian"meansanyreceiver,trustee,assignee,liquidatororsimilarofficialunderanyBankruptcyLaw.

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IfanyEventofDefault(otherthananEventofDefaultspecifiedinclause(4)or(5)above)withrespecttothenotesoccursandiscontinuing,eitherthetrusteeortheholdersofatleast25%inprincipalamountofthethenoutstandingnotesmaydeclareallthenotestobedueandpayableimmediately.Uponanysuchdeclaration,thenotesshallbecomedueandpayableimmediately,byanoticeinwritingtous(andtothetrusteeifgivenbyholders).Notwithstandingtheforegoing,ifanEventofDefaultspecifiedinclause(4)or(5)abovehereofoccurswithrespecttous,alloutstandingnotesshallbecomedueandpayablewithoutfurtheractionornotice.

Notwithstandingtheforegoing,aDefaultunderclause(3)aboveisnotanEventofDefaultuntilthetrusteenotifiesus,ortheholdersofatleast25%inprincipalamountofthethenoutstandingnotesnotifyusandthetrustee,oftheDefault,andwefailtocuretheDefaultwithin90daysafterreceiptofthenotice.ThenoticemustspecifytheDefault,demandthatitberemediedandstatethatthenoticeisa"NoticeofDefault."

HoldersofnotlessthanamajorityinaggregateprincipalamountofthethenoutstandingnotesbynoticetothetrusteemayonbehalfoftheholdersofallofthenoteswaiveanyexistingDefaultorEventofDefaultanditsconsequencesundertheindenture,exceptacontinuingDefaultorEventofDefaultinthepaymentoftheprincipalof,premium,ifany,orintereston,thenotes(includinginconnectionwithanoffertopurchase)(provided,however,thattheholdersofamajorityinaggregateprincipalamountofthethenoutstandingnotesmayrescindanaccelerationanditsconsequences,includinganyrelatedpaymentDefaultthatresultedfromsuchacceleration,withrespecttothenotes).Uponanysuchwaiver,suchDefaultshallceasetoexist,andanyEventofDefaultarisingtherefromshallbedeemedtohavebeencuredforeverypurposeoftheindenture;butnosuchwaivershallextendtoanysubsequentorotherDefaultorimpairanyrightconsequentthereon.

ModificationandWaiver

Weandthetrusteemaysupplementoramendtheindenturewithrespecttothenoteswiththeconsentoftheholdersofatleastamajorityinprincipalamountoftheoutstandingnotes.Withouttheconsentoftheholderofeachnoteaffected,however,nomodificationmay:

• reducetheprincipalamountofthethenoutstandingnoteswhoseholdersmustconsenttoanamendment,supplementorwaiver;

• reducetheprincipaloforchangethefixedmaturityofanynotesoralteranyoftheprovisionswithrespecttotheredemptionofthenotes;

• reducetherateoforchangethetimeforpaymentofinterestonanynote;

• waiveaDefaultorEventofDefaultinthepaymentofprincipalof,orinterestorpremium,ifany,onthenotes(exceptarescissionofaccelerationofthenotesbytheholdersofnotesofatleastamajorityinaggregateprincipalamountofthethenoutstandingnotesandawaiverofthepaymentDefaultthatresultedfromsuchacceleration);

• makeanynotepayableinmoneyotherthanthatstatedinthenote;

• makeanychangeintheprovisionsoftheindenturerelatingtowaiversofpastDefaultsortherightsofholdersofnotestoreceivepaymentsofprincipalof,orinterestorpremium,ifany,onthenotes;

• waivearedemptionpaymentwithrespecttoanynote;

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• causethenotestobecomesubordinatedinrightofpaymenttoanyotherIndebtedness;or

• makeanychangeintheforegoingamendmentandwaiverprovisions.

Weandthetrusteemaysupplementoramendtheindentureorwaiveanyprovisionofthatindenturewithouttheconsentofanyholdersofthenotesincertaincircumstances,including:

• tocureanyambiguity,defectorinconsistency;

• toprovideforuncertificatednotesinadditiontoorinplaceofcertificatednotesortoaltertheprovisionsoftheindenturerelatedtotheformsofnotes(includingtherelateddefinitions)inamannerthatdoesnotadverselyaffectanyholderinanymaterialrespect;

• toprovidefortheassumptionofourobligationstotheholdersofthenotesbyasuccessortouspursuanttoprovisionsoftheindenturedescribedunder"Consolidation,MergerandSaleofAssets";

• tomakeanychangethatwouldprovideanyadditionalrightsorbenefitstotheholdersofthenotesorthatdoesnotadverselyaffectthelegalrightshereunderofanysuchholderinanymaterialrespectortosurrenderanyrightorpowerconferreduponus;

• tocomplywithrequirementsoftheSECinordertoeffectormaintainthequalificationoftheindentureundertheTrustIndentureAct;

• tochangeoreliminateanyoftheprovisionsoftheindenture;providedthatanysuchchangeoreliminationbecomeseffectiveonlywhentherearenooutstandingnotescreatedpriortotheexecutionofsuchamendmentorsupplementalindenturethatisadverselyaffectedinanymaterialrespectbythechangeinoreliminationoftheprovision;

• tosupplementanyoftheprovisionsoftheindenturetosuchextentnecessarytopermitorfacilitatethedefeasanceanddischargeofnotespursuanttotheindenture;provided,thatanysuchactiondoesnotadverselyaffecttheinterestoftheholdersofthenotesinanymaterialrespect;

• toevidenceandprovidetheacceptanceoftheappointmentofasuccessortrusteepursuanttothetermsthereof;

• toaddaguarantorofthenotes;and

• toconformanyprovisiontothis"DescriptionofNotes"section.

TheholdersofamajorityinprincipalamountoftheoutstandingnotesmaywaiveanyexistingorpastDefaultorEventofDefaultwithrespecttosuchnotes.Thoseholdersmaynot,however,waiveanyDefaultorEventofDefaultinanypaymentonanynoteorcompliancewithaprovisionthatcannotbeamendedorsupplementedwithouttheconsentofeachholderaffected.

DefeasanceandDischarge

Defeasance.Whenweusetheterm"defeasance,"wemeandischargefromsomeorallofourobligationsundertheindenture.Ifwedepositwiththetrusteeundertheindentureanycombinationofmoneyorgovernmentsecuritiessufficienttomakepaymentsonthenotes

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issuedundertheindentureonthedatesthosepaymentsaredue,then,atouroption,eitherofthefollowingwilloccur:

• wewillbedischargedfromourobligationswithrespecttothenotes("legaldefeasance");or

• wewillnolongerhaveanyobligationtocomplywithspecifiedrestrictivecovenantswithrespecttothenotes,thecovenantdescribedunder"—Consolidation,MergerandSalesofAssets"andotherspecifiedcovenantsundertheapplicableindenture,andtherelatedEventsofDefaultwillnolongerapply("covenantdefeasance").

Ifthenotesaredefeased,theholdersofthenoteswillnotbeentitledtothebenefitsoftheindenture,exceptforobligationstoauthenticateanddelivertemporarysecurities,registerthetransferorexchangeofnotes,replacemutilated,destroyed,lostandstolennotesandmaintainpayingagencies.Inthecaseofcovenantdefeasance,ourobligationtopayprincipal,premiumandinterestonthenoteswillalsosurvive.

Wewillberequiredtodelivertothetrusteeanopinionofcounselthatthedepositandrelateddefeasancewouldnotcausetheholdersofthenotestorecognizeincome,gainorlossforU.S.federalincometaxpurposesandthattheholderswouldbesubjecttoU.S.federalincometaxonthesameamounts,inthesamemannerandatthesametimesaswouldhavebeenthecaseifthedepositandrelateddefeasancehadnotoccurred.Ifweelectlegaldefeasance,thatopinionofcounselmustbebaseduponarulingfromtheU.S.InternalRevenueServiceorachangeinlawtothateffect.

SatisfactionandDischarge.Inaddition,theindenturewillceasetobeoffurthereffectwithrespecttothenotes,subjecttoexceptionsrelatingtocompensationandindemnityofthetrusteeundertheindentureandrepaymenttousofexcessmoneyorgovernmentsecurities,when:

• either

• allsuchnotestheretoforeauthenticatedanddelivered(otherthan(i)suchnoteswhichhavebeendestroyed,lostorstolenandwhichhavebeenreplacedorpaidasprovidedintheindentureand(ii)suchnotesforwhosepaymentmoneyhastheretoforebeendepositedintrustorsegregatedandheldintrustbyusandthereafterrepaidtousordischargedfromsuchtrust,asprovidedintheindenture)havebeendeliveredtothetrusteeforcancellation;or

• allsuchnotesnottheretoforedeliveredtothetrusteeforcancellation:

• havebecomedueandpayable,

• willbecomedueandpayableattheirStatedMaturitywithinoneyear,or

• aretobecalledforredemptionwithinoneyearunderarrangementssatisfactorytothetrusteeforthegivingofnoticeofredemptionbythetrusteeinournameandatourexpense;

andwe,inthecaseofthethreeprecedingbullets,havedepositedorcausedtobedepositedwiththetrustee,asfundsintrustforsuchpurpose,anamountinU.S.dollarsorU.S.governmentobligationsmaturingastoprincipalandinterestinsuchamountsandatsuchtimesaswill,togetherwithanyinterestthereon(butwithoutconsiderationofthereinvestmentofsuchinterest),besufficienttopayanddischargetheentireIndebtednessonsuchnotesnottheretoforedeliveredtothetrusteeforcancellation,forprincipalandanypremiumandinteresttothedateofsuchdeposit

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(inthecaseofnoteswhichhavebecomedueandpayable)ortotheStatedMaturityorredemptiondate,asthecasemaybe;

• wehavepaidorcausedtobepaidallothersumspayablebyuswithrespecttothenotes;and

• wehavedeliveredtothetrusteeanOfficers'Certificateandanopinionofcounsel,eachstatingthatallconditionsprecedentprovidedintheindentureorrelatingtothesatisfactionanddischargeoftheindenturewithrespecttothenoteshavebeencompliedwith.

TheTrustee

DeutscheBankTrustCompanyAmericasisthetrusteeundertheindenture.DeutscheBankTrustCompanyAmericasanditsaffiliatesmayperformcertaincommercialbankingservicesforusfromtimetotimeforwhichtheyreceivecustomaryfees.

TheTrustIndentureActcontainslimitationsontherightsofthetrustee,ifitoranyofitsaffiliatesisthenourcreditor,toobtainpaymentsofclaimsortorealizeoncertainpropertyreceivedforanysuchclaim,assecurityorotherwise.Thetrusteeanditsaffiliatesarepermittedtoengageinothertransactionswithus.If,however,thetrusteeacquiresanyconflictinginterest,itmusteliminatethatconflictorresignwithin90daysafterascertainingthatithasaconflictinginterestandaftertheoccurrenceofaDefaultundertheindenture,unlesstheDefaulthasbeencured,waivedorotherwiseeliminatedwithinthe90-dayperiod.

Payment;PayingAgentsandTransferAgents

Thetrusteewillbeappointedaspayingagentandtransferagentforthenotes.PaymentsonthenoteswillbemadeinU.S.dollarsattheofficeofthetrusteeandanypayingagent.Atouroption,however,paymentsmaybemadebywiretransferfornotesheldinbook-entryformorbycheckmailedtotheaddressofthePersonentitledtothepaymentasitappearsinthesecurityregister.

Iftheprincipaloforanypremiumorinterestonthenotesispayableonadaythatisnotabusinessday,thepaymentwillbemadeonthefollowingbusinessday.Subjecttotherequirementsofanyapplicableabandonedpropertylaws,thetrusteeandpayingagentwillpaytousuponwrittenrequestanymoneyheldbythemforpaymentsonthenotesthatremainsunclaimedforthreeyearsafterthedateuponwhichthatpaymenthasbecomedue.Afterpaymenttous,holdersentitledtothemoneymustlooktousforpayment.Inthatcase,allliabilityofthetrusteeorpayingagentwithrespecttothatmoneywillcease.

Definitions

"AttributableIndebtedness,"whenusedwithrespecttoanySale/LeasebackTransaction,means,asatthetimeofdetermination,thepresentvalue(discountedattheratesetforthorimplicitinthetermsoftheleaseincludedinsuchtransaction)ofthetotalobligationsofthelesseeforrentalpayments(otherthanamountsrequiredtobepaidonaccountoftaxes,maintenance,repairs,insurance,assessments,utilities,operatingandlaborcostsandotheritemswhichdonotconstitutepaymentsforpropertyrights)duringtheremainingtermoftheleaseincludedinsuchSale/LeasebackTransaction(includinganyperiodforwhichsuchleasehasbeenextended).Inthecaseofanyleasewhichisterminablebythelesseeuponthepaymentofapenalty,suchnetamountshallbethelesserofthenetamountdeterminedassumingterminationuponthefirstdatesuchleasemaybeterminated(inwhichcasethenetamountshallalsoincludetheamountofthepenalty,butnorentshallbeconsideredas

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requiredtobepaidundersuchleasesubsequenttothefirstdateuponwhichitmaybesoterminated)orthenetamountdeterminedassumingnosuchtermination.

"BankruptcyAct"meanstheBankruptcyActorTitle11oftheUnitedStatesCode,asamended.

"BoardofDirectors"meansourBoardofDirectorsorcomparablegoverningbodyoranycommitteethereofdulyauthorized,withrespecttoanyparticularmatter,toactbyoronbehalfofourBoardofDirectorsorcomparablegoverningbody.

"CapitalizedLeaseObligation"ofanyPersonmeansanyobligationofsuchPersontopayrentorotheramountsunderaleaseofproperty,realorpersonal,thatisrequiredtobeaccountedforasacapitalleaseforfinancialreportingpurposesinaccordancewithGAAP;andtheamountofsuchobligationshallbethecapitalizedamountthereofdeterminedinaccordancewithGAAP.

"ChangeofControl"meanstheoccurrenceofanyofthefollowing:(1)theconsummationofanytransaction(including,withoutlimitation,anymergerorconsolidation)theresultofwhichisthatany"person"(asthattermisusedinSection13(d)(3)oftheExchangeAct)(otherthanEnsco,anysubsidiaryoremployeebenefitplanofEnscooremployeebenefitplanofanysubsidiaryofEnsco)becomesthebeneficialowner(asdefinedinRules13d-3and13d-5undertheExchangeAct),directlyorindirectly,ofmorethan50%ofthevotingstockofEnscoorothervotingstockintowhichthevotingstockofEnscoisreclassified,consolidated,exchangedorchanged,measuredbyvotingpowerratherthannumberofshares;or(2)thedirectorindirectsale,transfer,conveyanceorotherdisposition(otherthanbywayofmergerorconsolidation),inoneormoreseriesoftransactionsapprovedbytheboardofdirectorsofEnscoaspartofasingleplan,ofallorsubstantiallyalloftheassetsofEnscoasshownonEnsco'smostrecentauditedbalancesheet,tooneormore"persons"(asthattermisdefinedintheindenture)(otherthanEnscooroneofthesubsidiariesofEnsco).Notwithstandingtheforegoing,atransactionwillnotbedeemedtoinvolveachangeofcontrolif(1)Enscobecomesadirectorindirectwholly-ownedsubsidiaryofaPersonand(2)(A)thedirectorindirectholdersofthevotingstockofsuchPersonimmediatelyfollowingthattransactionaresubstantiallythesameastheholdersofthevotingstockofEnscoimmediatelypriortothattransactionor(B)immediatelyfollowingthattransaction,nopersonorgroup(otherthanaPersonsatisfyingtherequirementsofthissentence)isthebeneficialowner,directlyorindirectly,ofmorethan50%ofthevotingstockofsuchPerson.

"ChangeofControlTriggeringEvent"meanstheoccurrenceofaChangeofControl,whichoccurrenceisfollowedbyaRatingDeclinewithin90daysthereof.

"ConsolidatedNetTangibleAssets"meansthetotalamountofassets(afterdeductingapplicablereservesandotherproperlydeductibleitems)less:

• allcurrentliabilities(excludingliabilitiesthatareextendibleorrenewableatouroptiontoadatemorethan12monthsafterthedateofcalculationandexcludingcurrentmaturitiesoflong-termIndebtedness);and

• allgoodwill,tradenames,trademarks,patents,unamortizeddebtdiscountandexpenseandotherlikeintangibleassets.

WewillcalculateourConsolidatedNetTangibleAssetsbasedonourmostrecentquarterlybalancesheetandinaccordancewithGAAP.

"Default"meansanyevent,actorconditionthatis,orafternoticeorthepassageoftimeorbothwouldbe,anEventofDefault.

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"Entity"meansacorporation,limitedliabilitycompanyorbusinesstrust(orfunctionalequivalentoftheforegoingunderapplicableforeignlaw).

"FundedIndebtedness"meansallIndebtednessthatmaturesonorisrenewabletoadatemorethanoneyearafterthedatetheIndebtednessisincurred.

"GAAP"meansUnitedStatesgenerallyacceptedaccountingprinciplesandpoliciesconsistentwiththoseappliedinthepreparationofourfinancialstatements.

"Indebtedness"means:

• allindebtednessforborrowedmoney(whetherfullorlimitedrecourse);

• allobligationsevidencedbybonds,debentures,notesorothersimilarinstruments;

• allobligationsunderlettersofcreditorothersimilarinstruments,otherthanstandbylettersofcredit,performancebondsandotherobligationsissuedintheordinarycourseofbusiness,totheextentnotdrawnor,totheextentdrawn,ifsuchdrawingisreimbursednotlaterthanthethirdbusinessdayfollowingdemandforreimbursement;

• allobligationstopaythedeferredandunpaidpurchasepriceofpropertyorservices,excepttradepayablesandaccruedexpensesincurredintheordinarycourseofbusiness;

• allCapitalizedLeaseObligations;

• allIndebtednessofotherssecuredbyaLienonanyassetofthePersoninquestion(providedthatiftheobligationssosecuredhavenotbeenassumedinfullorarenototherwisefullythePerson'slegalliability,thensuchobligationsmaybereducedtothevalueoftheassetortheliabilityofthePerson);or

• allIndebtednessofothers(otherthanendorsementsintheordinarycourseofbusiness)guaranteedbythePersoninquestiontotheextentofsuchguarantee.

"IssueDate"meansthedateonwhichthenotesarefirstauthenticatedanddeliveredundertheindenture.

"JointVenture"meansanypartnership,corporationorotherentityinwhichuptoandincluding50%ofthepartnershipinterests,outstandingvotingstockorotherequityinterestsisowned,directlyorindirectly,byusand/oroneormoreSubsidiaries.AJointVentureisnottreatedasaSubsidiary.

"Lien"meansanymortgage,pledge,lien,charge,securityinterestorsimilarencumbrance.Forpurposesoftheindenture,weoranyofourSubsidiariesshallbedeemedtoownsubjecttoaLienanyassetwhichithasacquiredorholdssubjecttotheinterestofavendororlessorunderanyconditionalsaleagreement,CapitalizedLeaseObligationorothertitleretentionagreementrelatingtosuchasset.

"Maturity"whenusedwithrespecttothenotes,meansthedateonwhichtheprincipalofsuchnoteoraninstallmentofprincipalbecomesdueandpayableasthereinorhereinprovided,whetherattheStatedMaturityorbydeclarationofacceleration,callforredemptionorotherwise.

"Moody's"meansMoody'sInvestorsService,Inc.,anditssuccessors.

"Officers"meansourChairmanoftheBoard,President,VicePresident,Treasurer,Controller,Secretary,AssistantTreasurer,AssistantControllerorAssistantSecretary.

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"Officers'Certificate"meansacertificatesignedbytwoOfficersanddeliveredtothetrustee,whichcertificateshallbeincompliancewiththeindenture.

"PariPassuIndebtedness"meansanyofourIndebtedness,whetheroutstandingontheIssueDateorthereaftercreated,incurredorassumed,unless,inthecaseofanyparticularIndebtedness,theinstrumentcreatingorevidencingthesameorpursuanttowhichthesameisoutstandingexpresslyprovidesthatsuchIndebtednessshallbesubordinatedinrightofpaymenttothenotes.

"PermittedLiens"shallmean(i)LiensexistingontheIssueDate;(ii)Liensonpropertyorassetsof,oranysharesofstockof,orotherequityinterestsin,orIndebtednessof,anyPersonexistingatthetimesuchPersonbecomesaSubsidiaryofusoratthetimesuchPersonismergedintoorconsolidatedwithusoranyofourSubsidiariesoratthetimeofasale,leaseorotherdispositionofthepropertiesofaPerson(oradivisionthereof)asanentiretyorsubstantiallyasanentiretytousoraSubsidiary,andnotincurredincontemplationofsuchmerger,consolidation,sale,leaseorotherdisposition;(iii)LiensinfavorofusoranyofourSubsidiariesorLienssecuringdebtofaSubsidiaryowingtousortoanotherSubsidiary;(iv)Liensinfavorofgovernmentalbodiestosecurepartial,progress,advanceorotherpaymentsorperformancepursuanttotheprovisionsofanycontractorstatute;(v)Lienssecuringindustrialrevenue,pollutioncontrolorsimilarrevenuebonds;(vi)Liensonassetsexistingatthetimeofacquisitionthereof,securingalloranyportionofthecostofacquiring,constructing,improving,developing,expandingorrepairingsuchassetsorsecuringIndebtednessincurredpriorto,atthetimeof,orwithin24monthsafter,thelateroftheacquisition,thecompletionofconstruction,improvement,development,expansionorrepairorthecommencementofcommercialoperationofsuchassets,forthepurposeof(a)financingalloranypartofthepurchasepriceofsuchassetsor(b)financingalloranypartofthecostofconstruction,improvement,development,expansionorrepairofanysuchassets;(vii)statutoryliensorlandlords',carriers',warehouseman's,mechanics',suppliers',materialmen's,repairmen's,maritimeorotherlikeLiensarisingintheordinarycourseofbusinessandwithrespecttoamountsnotyetdelinquentorbeingcontestedingoodfaithbyappropriateproceedings;(viii)Liensinconnectionwithinremandotherlegalproceedings,whicharebeingcontestedingoodfaith;(ix)Lienssecuringtaxes,assessments,governmentchargesorleviesnotyetdueordelinquent,orwhichcanthereafterbepaidwithoutpenalty,orwhicharebeingcontestedingoodfaithbyappropriateproceedings;(x)Liensonthestock,partnershiporotherequityinterestofusoranySubsidiaryinanyJointVentureoranySubsidiarythatownsanequityinterestinsuchJointVenturetosecureIndebtedness,providedtheamountofsuchIndebtednessiscontributedand/oradvancedsolelytosuchJointVenture;(xi)Liensincurredintheordinarycourseofbusinesstosecureperformanceoftenders,bidsorcontractsenteredintointheordinarycourseofbusiness,includingwithoutlimitationanyrightsofoffsetorliquidateddamages,penalties,orotherfeesthatmaybecontractuallyagreedtoinconjunctionwithanytender,bid,orcontractenteredintobyusoranyofourSubsidiariesintheordinarycourseofbusiness;(xii)LiensoncurrentassetsofusoranyofourSubsidiariessecuringourIndebtednessorIndebtednessofanysuchSubsidiary,respectively;(xiii)depositsmadeinconnectionwithmaintainingself-insurance,toobtainthebenefitsoflaws,regulationsorarrangementsrelatingtounemploymentinsurance,oldagepensions,socialsecurityorsimilarmattersortosecuresurety,appealorcustomsbonds;and(xiv)anyextensions,substitutions,replacementsorrenewalsinwholeorinpartofaLienenumeratedinclauses(i)through(xiii)above,providedthattheamountofIndebtednesssecuredbysuchextension,substitution,replacementorrenewalshallnotexceedtheprincipalamountofIndebtednessbeingsubstituted,extended,replacedorrenewed,togetherwiththeamountofanypremiums,fees,costsandexpensesassociatedwithsuchsubstitution,extension,replacementorrenewal,norshallthepledge,mortgageorlienbeextendedtoany

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additionalPrincipalPropertyunlessotherwisepermittedunderthecovenantdescribedunder"LimitationonLiens."

"Person"meansanyindividual,corporation,partnership,limitedliabilitycompany,jointventure,incorporatedorunincorporatedassociation,jointstockcompany,trust,unincorporatedorganizationorgovernmentorotheragencyorpoliticalsubdivisionthereoforotherentityofanykind.

"PrincipalProperty"meansanydrillingrigordrillship,orintegralportionthereof,ownedorleasedbyusoranySubsidiaryandusedfordrillingoffshoreoilandgaswells,which,intheopinionoftheBoardofDirectors,isofmaterialimportancetothebusinessofusandourSubsidiariestakenasawhole,butnosuchdrillingrigordrillship,orportionthereof,shallbedeemedofmaterialimportanceifitsnetbookvalue(afterdeductingaccumulateddepreciation)islessthan2%ofConsolidatedNetTangibleAssets.

"RatingCategory"means:

(1)withrespecttoS&P,anyofthefollowingcategories:AAA,AA,A,BBB,BB,B,CCC,CC,CandD(orequivalentsuccessorcategories);and

(2)withrespecttoMoody's,anyofthefollowingcategories:Aaa,Aa,A,Baa,Ba,B,Caa,Ca,CandD(orequivalentsuccessorcategories).

"RatingDecline"meansadecreaseintheratingofthenotesbybothMoody'sandS&Pbyoneormoregradations(includinggradationswithinRatingCategoriesaswellasbetweenRatingCategories).Indeterminingwhethertheratingofthenoteshasdecreasedbyoneormoregradations,gradationswithinRatingCategories,namely+or–forS&P,and1,2,and3forMoody's,willbetakenintoaccount;forexample,inthecaseofS&P,aratingdeclineeitherfromBB+toBBorBB–toB+willconstituteadecreaseofonegradation.

"S&P"meansS&PGlobalRatings,adivisionofS&PGlobalInc.,anditssuccessors.

"Sale/LeasebackTransaction"meansanyarrangementwithanyPersonpursuanttowhichweoranySubsidiaryleasesanyPrincipalPropertythathasbeenoristobesoldortransferredbyusortheSubsidiarytosuchPerson,otherthan(1)temporaryleasesforaterm,includingrenewalsattheoptionofthelessee,ofnotmorethanfiveyears;(2)leasesbetweenusandaSubsidiaryorbetweenSubsidiaries;and(3)leasesofPrincipalPropertyexecutedbythetimeof,orwithin12monthsafterthelatestof,theacquisition,thecompletionofconstruction,alteration,improvementorrepair,orthecommencementofcommercialoperationofthePrincipalProperty.

"StatedMaturity"whenusedwithrespecttothenotesoranyinstallmentofprincipalthereoforinterestthereon,meansthedatespecifiedasthefixeddateonwhichtheprincipalofthenotesorsuchinstallmentofprincipalorinterestisdueandpayable.

"Subsidiary"meansaPersonatleastamajorityoftheoutstandingVotingStockofwhichisowned,directlyorindirectly,byusorbyoneormoreotherSubsidiaries,orbyusandoneormoreotherSubsidiaries.AJointVentureisnottreatedasaSubsidiary.

"VotingStock"means,withrespecttoanyPerson,securitiesofanyclassorclassesofcapitalstockofsuchPersonentitlingtheholdersthereof(whetheratalltimesoratthetimesthatsuchclassofcapitalstockhasvotingpowerbyreasonofthehappeningofanycontingency)tovoteintheelectionofmembersoftheboardofdirectorsorcomparablebodyofsuchPerson.

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"WhollyOwnedSubsidiary"means,withrespecttoaPerson,anySubsidiaryofthatPersontotheextent

(1) alloftheVotingStockofsuchSubsidiary,otherthananydirector'squalifyingsharesmandatedbyapplicablelaw,isowneddirectlyorindirectlybysuchPersonor

(2) suchSubsidiaryisorganizedinaforeignjurisdictionandisrequiredbytheapplicablelawsandregulationsofsuchforeignjurisdictiontobepartiallyownedbyanotherPerson,ifsuchPerson:

• directlyorindirectlyownstheremainingcapitalstockofsuchSubsidiaryand

• bycontractorotherwise,controlsthemanagementandbusinessofsuchSubsidiaryandderivestheeconomicbenefitsofownershipofsuchSubsidiarytosubstantiallythesameextentasifsuchSubsidiarywereaWhollyOwnedSubsidiary.

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CERTAINU.S.FEDERALANDU.K.TAXCONSEQUENCES

U.S.FederalIncomeTaxConsequencestoU.S.holders(asdefinedbelow)

ThefollowingdiscussionsummarizescertainU.S.federalincometaxconsequencesoftheownershipanddispositionofthenotesbyU.S.holders(asdefinedbelow)whoholdthenotesas"capitalassets"(withinthemeaningofSection1221oftheInternalRevenueCodeof1986,asamended(the"Code"))andwhopurchasethenotesforcash,inthisofferingattheir"issueprice"(i.e.,thefirstpriceatwhichasubstantialamountofthenotesissoldtothepublic,excludingsalestobondhouses,brokers,orsimilarpersonsororganizationsactinginthecapacityofunderwriters,placementagentsorwholesalers).Thisdiscussionisnotacompletediscussionofallthepotentialtaxconsequencesoftheownershipanddispositionofnotesthatmayberelevanttoyou.ThisdiscussionisbasedupontheCode,regulationsissuedundertheCode,administrativerulingsandcourtdecisions,allasineffectonthedateofthisprospectussupplement,andallofwhicharesubjecttochange,possiblyonaretroactivebasisthatcouldadverselyaffectaholderofthenotes,ortodifferentinterpretations.WecannotassureyouthattheInternalRevenueService(the"IRS")willnotchallengeoneormoreofthetaxconsequencesdescribedinthisprospectussupplement.Wehavenotobtained,nordoweintendtoobtain,arulingfromtheIRSwithrespecttotheU.S.federaltaxconsequencesofowningordisposingofthenotes.

ThisdiscussiondoesnotaddressallU.S.federalincometaxconsiderationsthatmayberelevanttoaparticularU.S.holderinlightoftheU.S.holder'scircumstancesortocertaincategoriesofinvestorsthatmaybesubjecttospecialrules,suchasfinancialinstitutions,regulatedinvestmentcompanies,insurancecompanies,realestateinvestmenttrusts,retirementplans,non-U.S.trustsorestateswithU.S.beneficiaries,individualretirementaccounts,tax-deferredaccounts,holderssubjecttoalternativeminimumtax,dealersortradersinsecurities,partnershipsorotherpass-throughentities(orinvestorsinsuchentities),U.S.expatriates,personswhosefunctionalcurrencyisnottheU.S.dollarorpersonswhoholdthenotesaspartofahedge,conversiontransaction,straddleorotherintegratedtransaction.ThisdiscussionalsodoesnotaddressU.S.federaltaxconsequencesotherthanU.S.federalincometaxconsequences(suchasestateorgifttaxconsequences),orthetaxconsiderationsarisingunderthelawsofanystate,localornon-U.S.jurisdictionorunderanyapplicabletaxtreaties.ThediscussionalsodoesnotaddressanytaxconsequencesofanyholderwhoisnotaU.S.holder.

Forpurposesofthisdiscussion,youarea"U.S.holder"ifyouareabeneficialownerofnotesandyouarea"U.S.person"forU.S.federalincometaxpurposes.A"U.S.person"is:

• anindividualwhoisacitizenoftheU.S.oraresidentalienoftheU.S.forU.S.federalincometaxpurposes;

• anentitytreatedasacorporationforU.S.federalincometaxpurposes,createdororganizedinorunderthelawsoftheU.S.orofanystatethereofortheDistrictofColumbia;

• anestatewhoseincomeissubjecttoU.S.federalincometaxationregardlessofitssource;or

• atrustifaU.S.courtisabletoexerciseprimarysupervisionovertheadministrationofthetrustandoneormoreU.S.personshavetheauthoritytocontrolallsubstantialdecisionsofthetrust,oratrustthathasavalidelectionineffectunderapplicableregulationstobetreatedasaU.S.person.

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IfanentitytreatedasapartnershipforU.S.federalincometaxpurposesholdsthenotes,thetaxtreatmentofapartnerwillgenerallydependonthestatusofthepartnerandontheactivitiesofthepartnership.Partnersofpartnershipsconsideringaninvestmentinthenotesshouldconsulttheirtaxadvisors.

Thisdiscussionisintendedforgeneralinformationpurposesonly.WeurgeyoutoconsultyourowntaxadvisorsregardingtheparticularU.S.federalincome,estateandgifttaxconsequencestoyouofowninganddisposingofnotes,anytaxconsequencesthatmayariseunderthelawsofanyrelevantnon-U.S.,state,localorothertaxingjurisdictionorunderanyapplicabletaxtreaty,aswellaspossibleeffectsofchangesinfederalorothertaxlaws.Investorswhopurchasenotessubsequenttotheiroriginalissuanceshouldconsulttheirowntaxadvisorswithrespecttothetaxtreatmentofsuchpurchase(including,withoutlimitation,anymarketdiscountorbondpremiumassociatedwiththepurchaseofsuchnotes).

Effect of Certain Contingencies

Incertaincircumstances(see,e.g.,"DescriptionofNotes—OptionalRedemption"and"DescriptionofNotes—ChangeofControlOffer"),wemaybeobligatedtopayamountsonthenotesthatareinexcessofstatedinterestandprincipal.ThepossibilityofsuchpaymentsmayimplicatespecialrulesunderU.S.TreasuryRegulationsgoverning"contingentpaymentdebtinstruments."Accordingtothoseregulations,thepossibilitythatadditionalpaymentswillbemadewillnotcausethenotestobecontingentpaymentdebtinstrumentsif,asofthedatethenotesareissued,thereisonlyaremotechancethatanysuchpaymentswillbemade,eachsuchpaymentisconsideredincidentalor,incertaincircumstances,ifitissignificantlymorelikelythannotthatnosuchpaymentswillbemade.Basedontheforegoing,weintendtotakethepositionthatthenotesarenotsubjecttothecontingentpaymentdebtrules.Ifanyadditionalpaymentsareinfactmade,holdersgenerallywillberequiredtorecognizesuchamountsasincome.

OurdeterminationthatthenotesarenotcontingentpaymentdebtinstrumentsisbindingonholdersunlesstheydisclosetheircontrarypositionstotheIRSinthemannerrequiredbyapplicableU.S.TreasuryRegulations.Ourdeterminationthatthenotesarenotcontingentpaymentdebtinstrumentsisnot,however,bindingontheIRS.IftheIRSweretosuccessfullychallengeourdeterminationandthenotesweretreatedascontingentpaymentdebtinstruments,holderssubjecttoU.S.federalincometaxationwouldberequired,amongotherthings,to(i)accrueinterestincomebasedonaprojectedpaymentscheduleandacomparableyield(whichcouldbeahigherratethanthestatedinterestrateonthenotes)regardlessoftheirmethodoftaxaccountingand(ii)treatasordinaryincome,ratherthancapitalgain,anygainrecognizedonasale,exchangeorredemptionofanote.Intheeventthatanyoftheabovecontingenciesweretooccur,itwouldaffecttheamountandtimingoftheincomerecognizedbyaU.S.holder.

Theremainderofthisdiscussionassumesthatthenoteswillnotbetreatedascontingentpaymentdebtinstruments.Holdersofthenotesareurgedtoconsulttheirowntaxadvisorsregardingthepotentialapplicationtothenotesofthecontingentpaymentdebtinstrumentrulesandtheconsequencesthereof.

PaymentsofInterest

Interestonanote(withoutreductionforanytaxwithheldandincludinganyAdditionalAmountspaidinrespectofsuchtaxes)generallywillbeincludableingrossincomebyaU.S.

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holderasordinaryincomeatthetimetheinterestiseitherreceivedoraccruedinaccordancewithsuchU.S.holder'sregularmethodofaccountingforU.S.federalincometaxpurposes.

Allsuchamountsofinterest(includinganyAdditionalAmounts)willgenerallyconstituteforeignsourceinterestincomeforU.S.federalincometaxpurposes.Ifanynon-U.S.taxesweretobepaidorwithheldinrespectofpaymentsonthenotes(includinganyAdditionalAmounts),aU.S.holdermaybeeligible,subjecttoanumberofcomplexlimitations(includingthattheelectiontodeductorcreditnon-U.S.taxesappliestoallofyournon-U.S.taxesforaparticulartaxyear),foradeductionoraforeigntaxcredit.Withcertainexceptions,interestonthenotes(includinganyAdditionalAmounts)willbetreatedas"passivecategoryincome,"orinthecaseofcertainU.S.holders,"generalcategoryincome,"forpurposesofcomputingtheforeigntaxcreditallowableundertheCode.TherulesgoverningforeigntaxcreditsarecomplexandaU.S.holderofnotesshouldconsultitstaxadvisorregardingtheavailabilityoftheforeigntaxcreditinitssituation.

Sale,Exchange,orOtherTaxableDispositionoftheNotes

Uponasale,taxableexchange,retirement,redemptionorothertaxabledispositionofanote,aU.S.holdergenerallywillrecognizegainorlossequaltothedifference,ifany,betweentheamountreceiveduponsuchtaxabledisposition(lessanyamountattributabletoaccruedbutunpaidinterest,whichwillbetaxableasordinaryincomeifnotpreviouslyincludedingrossincome)andtheU.S.holder'sadjustedtaxbasisinthenoteatthattime.AU.S.holder'sadjustedtaxbasisinanotewillgenerallyequalsuchholder'soriginalpurchasepriceforthenote.

AnygainorlossrealizedbyaU.S.holderonthesale,taxableexchange,retirement,redemptionorothertaxabledispositionofanotegenerallywillbetreatedasU.S.sourcecapitalgainorloss,andwillbelong-termcapitalgainorlossif,atthetimeofsale,exchange,retirementorothertaxabledisposition,thenotehasbeenheldformorethanoneyear;otherwise,thecapitalgainorlosswillbeshort-term.Undercurrentlaw,netlong-termcapitalgainrecognizedbycertainU.S.holders(includingindividuals)isgenerallytaxedatlowerratesthanitemsofordinaryincome.Thedeductibilityofcapitallossesissubjecttolimitations.Youshouldconsultyourtaxadvisorregardingthetreatmentofcapitalgainsandlosses.

InformationReportingandBackupWithholding

InformationreturnsmaybefiledwiththeInternalRevenueServiceinconnectionwithpaymentsonthenotesandtheproceedsfromasaleorotherdispositionofthenotes.AUSholdermaybesubjecttoUSbackupwithholdingonthesepaymentsiftheUSholderfailstoprovideacorrecttaxpayeridentificationnumbertothepayingagentandcomplywithcertaincertificationproceduresorotherwiseestablishanexemptionfrombackupwithholding.TheamountofanybackupwithholdingfromapaymenttoaUSholderwillbeallowedasacreditagainsttheUSholder'sUSfederalincometaxliabilityandmayentitletheUSholdertoarefund,providedthattherequiredinformationistimelyfurnishedtotheInternalRevenueService.

ForeignFinancialAssetReporting

CertainU.S.holderswhoholdinterestsin"specifiedforeignfinancialassets,"suchasthenotes,mayberequiredtodisclosecertaininformationrelatingtoeach"specifiedforeignfinancialasset"byattachingacompleteIRSForm8938,StatementofSpecifiedForeignAssets,totheirU.S.federalincometaxreturnfortherelevanttaxableyeariftheaggregate

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valueofsuchassetsexceedsacertainthreshold,subjecttocertainexceptions(includinganexceptionfornotesheldinaccountsmaintainedbyfinancialinstitutions,inwhichcasetheaccountitselfmaybereportableifmaintainedbyanon-U.S.financialinstitution).Youshouldconsultyourtaxadvisorregardingyourinformationreportingrequirements,includingthesignificantpenaltiesfornon-compliance.

MedicareTax

CertainU.S.holdersthatareindividuals,estatesortrustswillbesubjecttoa3.8%tax(the"MedicareTax")onthelesserof(a)theU.S.holder's"netinvestmentincome"fortherelevanttaxableyearand(b)theexcessoftheU.S.holder'smodifiedadjustedgrossincomeforthetaxableyearoveracertainthreshold(whichinthecaseofindividualswillbebetween$125,000and$250,000dependingontheindividual'scircumstances).AU.S.holder'snetinvestmentincomewillgenerallyincludeitsinterestincomeanditsnetgainsfromthedispositionofnotes,unlesssuchinterestincomeornetgainsarederivedintheordinarycourseoftheconductofatradeorbusiness(otherthanatradeorbusinessthatconsistsofcertainpassiveortradingactivities).AU.S.holderthatisanindividual,estateortrustshouldconsultitstaxadvisorregardingtheapplicabilityoftheMedicareTaxtoitsincomeandgainsinrespectofitsinvestmentinthenotes.

U.K.TaxConsequences

ThefollowingsummaryisofageneralnatureanddescribescertainUKtaxconsiderationsthatrelatetothenotesandisbasedoncurrentUKlawandthepracticeofH.M.Revenue&Customs.Itisnottaxadvice.Thecommentsrelateonlytothepositionofpersonswhoaretheabsolutebeneficialownersoftheirnotesandanypaymentsinrespectofsuchnotesandmaynotapplytocertainclassesofpersonssuchasdealersandholderswhoareconnectedwithusforrelevanttaxpurposes.ThissectionoffersgeneralguidanceonlyandinparticulardoesnotdiscusstheUKtaxtreatmentrelevanttoconvertibleorexchangeablesecurities,assetlinkedsecuritiesorsecuritiesissuedatanythingotherthannodiscountorafixeddiscounttotheirredemptionamount.

PleaseconsultyourowntaxadvisorconcerningtheconsequencesofowningthesedebtsecuritiesinyourparticularcircumstancesunderUKlawandthelawsofanyothertaxingjurisdiction.

InterestPayments

Ifthenotesareissuedwitharedemptionpremium,thenanysuchpremiummayconstituteinterestforUKtaxpurposesandsobetreatedinthemannerdescribedbelow.Referencesto"interest"inthissectionmeaninterestasunderstoodinUKtaxlaw.Thestatementsbelowdonottakeaccountofanydifferentdefinitionsofinterestwhichmayprevailunderanyotherlaworwhichmaybecreatedbythetermsandconditionsofthenotesoranyrelateddocumentation.

PaymentsofinterestonthenotesissuedbytheCompanywillnotbesubjecttowithholdingordeductionfororonaccountofUKtaxationbecausethenoteswillbetreatedas"quotedEurobonds"withinthemeaningofsection987oftheIncomeTaxAct2007(the"Act")solongastheyarelistedona"recognisedstockexchange"withinthemeaningofSection1005oftheAct.TheNewYorkStockExchangewillbea"recognisedstockexchange"solongasitisregisteredwiththeSECasanationalsecuritiesexchange.

Evenifthenotesdonotqualifyas"quotedEurobonds,"thewithholdingobligationisdisappliedinrespectofpaymentstoholderswhotheCompanyreasonablybelievesareeither

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aUKresidentcompanyoranon-UKresidentcompanycarryingonatradeintheUKthroughaUKpermanentestablishmentwhichiswithinthechargetocorporationtax,orfallwithinvariouscategoriesenjoyingaspecialtaxstatus(includingcharitiesandpensionfunds),orarepartnershipsconsistingofsuchpersons(unlessHMRevenue&Customsdirectsotherwise).

Inallothercases,paymentsofinterestwillgenerallybemadeafterdeductionoftaxatthebasicrate,whichiscurrently20%.CertainholdersofnoteswhoareresidentintheUSmaybeentitledtoreceivepaymentsfreeofdeductionsfororonaccountofUKtaxundertheUK—USdoubletaxationtreatyandmaythereforebeabletoobtainadirectiontothateffectfromtheappropriatetaxationauthorityintheUK.Holdersofnoteswhoareresidentinotherjurisdictionsmayalsobeabletoreceivepaymentfreeofdeductionsorsubjecttoalowerrateofdeductionunderanappropriatedoubletaxationtreatyandmaybeabletoobtainadirectiontothateffect.However,suchadirectionwill,ineithercase,onlybeissuedonpriorapplicationtotherelevanttaxauthoritiesbytheholderinquestion.Ifsuchadirectionisnotinplaceatthetimeapaymentofinterestismade,thepersonmakingthepaymentwillberequiredtowithholdtax,althoughaholderofnotesresidentinanotherjurisdictionwhoisentitledtoreliefmaysubsequentlyclaimtheamount,oraproportionoftheamountwithheld,asappropriate,fromHMRevenue&Customs.

TheinterestonnotesissuedbytheCompanywillhaveaUKsourcefortaxpurposesand,assuch,maybesubjecttoincometaxbydirectassessmentevenwherepaidwithoutwithholding.However,interestwithaUKsourcereceivedwithoutdeductionorwithholdingonaccountofUKtaxwilleffectivelynotbechargeabletoUKtaxinthehandsofapersonwhoisnotresidentfortaxpurposesintheUKunlessthatpersoncarriesonatrade,professionorvocationintheUKthroughabranchoragency(or,forholderswhoarecompanies,throughapermanentestablishment)intheUKinconnectionwithwhichtheinterestisreceivedortowhichthenotesareattributable.Therearecertainexceptionsforinterestreceivedbycertaincategoriesofagents(suchassomebrokersandinvestmentmanagers).

TaxonOwnershipandDisposition

AholderwhoisnotresidentintheUKwillnotbeliabletoUKtaxationinrespectofadisposal(includingredemption)ofthenotes,anygainaccruedinrespectofthenotesoranychangeinthevalueofthenotes,unless,atthetimeofthedisposal,theholdercarriesonatrade,professionorvocationintheUKthroughabranchoragency(or,forcorporateholders,apermanentestablishment)andthenoteswereusedinorforthepurposesofthattrade,professionorvocationoracquiredfortheusebyorforthepurposesofthebranchoragencyorpermanentestablishmentorusedorheldforthepurposesofthebranchoragencyorpermanentestablishment.

IngeneralholderswhicharewithinthechargetoUKcorporationtaxwillbetreatedfortaxpurposesasrealisingprofits,gainsorlossesinrespectofthenotesonabasiswhichisbroadlyinaccordancewiththeirstatutoryaccountingtreatmentsolongastheaccountingtreatmentisinaccordancewithgenerallyacceptedaccountingpracticeasthattermisdefinedfortaxpurposes.Suchprofits,gainsandlosses(or,wheretheholder'sfunctionalcurrencyisnotsterling,thenthesterlingequivalentofsuchprofits,gainsandlossesascomputedintheholder'sfunctionalcurrency)willbetakenintoaccountincomputingtaxableincomeforcorporationtaxpurposes.

IftheholderisanindividualresidentintheUK,heorshemayhavetoaccountforcapitalgainstaxinrespectofanygainsarisingonadisposalofthenotes,unlessthenotesare"qualifyingcorporatebonds"withinthemeaningofsection117oftheTaxationofChargeableGainsAct1992.Ifthisisthecase,neitherchargeablegainsnorallowablelosseswillariseon

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adisposalofthenotesforthepurposesoftaxationofchargeablegains.Anycapitalgainswouldbecalculatedbycomparingthesterlingvaluesonpurchaseanddisposalofthenotes,soaliabilitytotaxcouldarisewherethenon-sterlingamountreceivedonadisposalwaslessthanorthesameastheamountpaidforthenotes.

Ifthenoteswereissuedatasignificantordeepdiscount(withinthemeaningofPart4,Chapter8oftheIncomeTax(TradingandOtherIncome)Act2005)totheirredemptionamountthentheywouldbea"qualifyingcorporatebond"foraholderwithinthechargetocapitalgainstaxbutallprofitsandlossesontheirdisposalwouldbetaxedasincome.

Theprovisionsoftheaccruedincomescheme(the"Scheme")mayapplytocertainholderswhoaresubjecttoincometax,inrelationtoatransferofthenotes.OnatransferofsecuritieswithaccruedinteresttheSchemeusuallyappliestodeemthetransferortoreceiveanamountofincomeequaltotheaccruedinterestandtotreatthedeemedoractualinterestsubsequentlyreceivedbythetransfereeasreducedbyacorrespondingamount.Generally,personswhoarenotresidentintheUKandwhodonotcarryonatradeintheUKthroughabranchoragencytowhichthenotesareattributablewillnotbesubjecttotheprovisionsoftheserules.

AholderwhoisanindividualandwhoceasestoberesidentfortaxpurposesintheUKforaperiodoffiveyearsorlessandwhodisposesofnotesduringthatperiodmaybeliabletoUKtaxationonchargeablegainsarisingduringtheperiodofabsence,subjecttoanyavailableexemptionorrelief.

ProvisionofInformationbyand/ortoHMRevenue&Customs

HMRevenue&Customshaspowerstoobtaininformation(includingthenameandaddressofthebeneficialowneroftheinterest)inrelationtothenotesfromarangeofpersons,includinganypersonintheUnitedKingdom:

• whoeitherpaysinteresttoorreceivesinterestforthebenefitofanindividual;or

• whoeitherpaysamountspayableontheredemptionofthenoteswhichare"deeplydiscountedsecurities"to,orreceivessuchamountsforthebenefitof,anindividual(althoughHMRCpublishedpracticeindicatesthatitwillnotexerciseitspowertorequirethisinformationwheresuchamountsarepaidonorbeforeApril5,2018).

Suchinformationmay,incertaincircumstances,beexchangedbyHMRCwiththetaxauthoritiesofotherjurisdictions.

StampDutyandStampDutyReserveTax

NoUKstampdutyorstampdutyreservetaxwillgenerallybepayablebyaholderofthenotesontheissueorredemptionofthenotesbytheCompany.

NoliabilityforUKstampdutyorstampdutyreservetaxshouldariseonatransferof,oranagreementtotransfer,thenotes.

Theproposedfinancialtransactiontax("FTT")

OnFebruary14,2013,theEuropeanCommissionpublishedaproposal(the"Commission'sProposal")foraDirectiveforacommonFTTinBelgium,Germany,Estonia,Greece,Spain,France,Italy,Austria,Portugal,SloveniaandSlovakia(the"participatingMemberStates").

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TheCommission'sProposalhasverybroadscopeandcould,ifintroduced,applytodealingsinthenotes(includingsecondarymarkettransactions)incertaincircumstances.

UndertheCommission'sProposaltheFTTcouldapplyincertaincircumstancestopersonsbothwithinandoutsideoftheparticipatingMemberStates.Generally,itwouldapplytodealingsinthenoteswhereatleastonepartyisafinancialinstitution,andatleastonepartyisestablishedinaparticipatingMemberState.Afinancialinstitutionmaybe,orbedeemedtobe,"established"inaparticipatingMemberStateinabroadrangeofcircumstances,including(a)bytransactingwithapersonestablishedinaparticipatingMemberStateor(b)wherethefinancialinstrumentwhichissubjecttothedealingsisissuedinaparticipatingMemberState.

AdditionalEUMemberStatesmaydecidetoparticipateand/orparticipatingMemberStatesmaydecidetowithdraw.ItwasannouncedinDecember2015thatEstoniahadwithdrawn.TheCounciloftheEuropeanUnionmostrecentlydiscussedtheprogressofworkontheremainingopenissuesonDecember6,2016.

TheFTTproposalremainssubjecttonegotiationbetweentheparticipatingmemberstatesandthescopeandtimingofanysuchtaxisuncertain.

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BOOK-ENTRY,DELIVERYANDFORM

Exceptassetforthbelow,thenoteswillberepresentedbyoneormorepermanentglobalnotesinregisteredformwithoutinterestcoupons("globalnotes").TheglobalnoteswillbedepositeduponissuancewiththetrusteeascustodianforDTC,inNewYork,NewYork,andregisteredinthenameofDTC'snominee,Cede&Co.,forcredittoanaccountofadirectorindirectparticipantinDTCasdescribedbelow.

Exceptassetforthbelow,theglobalnotesmaybetransferred,inwholeandnotinpart,onlytoanothernomineeofDTCortoasuccessorofDTCoritsnominee.Beneficialinterestsintheglobalnotesmaynotbeexchangedfordefinitivenotesinregisteredcertificatedform("certificatednotes")exceptinthelimitedcircumstancesdescribedbelow.See"—CertificatedNotes."Exceptinthelimitedcircumstancesdescribedbelow,ownersofbeneficialinterestsintheglobalnoteswillnotbeentitledtoreceivephysicaldeliveryofsuchnotesincertificatedform.

BeneficialinterestsintheglobalnotesmaybeheldthroughClearstreamBanking,S.A.("Clearstream")ortheEuroclearSystem("Euroclear")(asindirectparticipantsinDTC).

TransfersofbeneficialinterestsintheglobalnoteswillbesubjecttotheapplicablerulesandproceduresofDTCanditsdirectorindirectparticipants(including,ifapplicable,thoseofClearstreamandEuroclear),whichmaychangefromtimetotime.

DepositoryProcedures

ThefollowingdescriptionoftheoperationsandproceduresofDTC,ClearstreamandEuroclearisprovidedsolelyasamatterofconvenience.Theseoperationsandproceduresaresolelywithinthecontroloftherespectivesettlementsystemsandaresubjecttochangesbythem.Wetakenoresponsibilityfortheseoperationsandproceduresandurgeinvestorstocontactthesystemortheirparticipantsdirectlytodiscussthesematters.

DTChasadvisedusthatDTCisalimited-purposetrustcompanyorganizedunderthelawsoftheStateofNewYork,a"bankingorganization"withinthemeaningoftheNewYorkBankingLaw,amemberoftheFederalReserveSystem,a"clearingcorporation"withinthemeaningoftheUniformCommercialCodeanda"clearingagency"registeredpursuanttotheprovisionsofSection17AoftheExchangeAct.DTCwascreatedtoholdsecuritiesforitsparticipatingorganizations(collectively,the"participants")andtofacilitatetheclearanceandsettlementoftransactionsinthosesecuritiesbetweenparticipantsthroughelectronicbook-entrychangesinaccountsofitsparticipants.Theparticipantsincludesecuritiesbrokersanddealers,banks,trustcompanies,clearingcorporationsandcertainotherorganizations.AccesstoDTC'ssystemisalsoavailabletootherentitiessuchasbanks,brokers,dealersandtrustcompaniesthatclearthroughormaintainacustodialrelationshipwithaparticipant,eitherdirectlyorindirectly(collectively,the"indirectparticipants").PersonswhoarenotparticipantsmaybeneficiallyownsecuritiesheldbyoronbehalfofDTConlythroughtheparticipantsortheindirectparticipants.Theownershipinterestsin,andtransfersofownershipinterestsin,eachsecurityheldbyoronbehalfofDTCarerecordedontherecordsoftheparticipantsandindirectparticipants.

DTChasalsoadvisedusthat,pursuanttoproceduresestablishedbyit:

(1)upondepositoftheglobalnotes,DTCwillcredittheaccountsofparticipantswithportionsoftheprincipalamountoftheglobalnotes;and

(2)ownershipoftheseinterestsinglobalnoteswillbeshownon,andthetransferofownershipoftheseinterestswillbeeffectedonlythrough,recordsmaintainedbyDTC

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(withrespecttotheparticipants)orbytheparticipantsandtheindirectparticipants(withrespecttootherownersofbeneficialinterestsinglobalnotes).InvestorsintheglobalnoteswhoareparticipantsinDTC'ssystemmayholdtheirintereststhereindirectlythroughDTC.

Investorsinglobalnoteswhoarenotparticipantsmayholdtheirintereststhereinindirectlythroughorganizations(includingClearstreamandEuroclear)thatareparticipantsinsuchsystem.ClearstreamandEuroclearmayholdinterestsintheglobalnotesonbehalfoftheirparticipantsthroughcustomers'securitiesaccountsintheirrespectivenamesonthebooksoftheirrespectivedepositories,whichareEuroclearBankS.A./N.V.,asoperatorofEuroclear,andCitibank,N.A.,asoperatorofClearstream.Allinterestsintheglobalnotes,includingthoseheldthroughClearstreamorEuroclear,maybesubjecttotheproceduresandrequirementsofDTC.ThoseinterestsheldthroughClearstreamorEuroclearmayalsobesubjecttotheproceduresandrequirementsofsuchsystems.

Thelawsofsomejurisdictionsrequirethatcertainpersonstakephysicaldeliveryindefinitiveformofsecuritiesthattheyownandtheabilitytotransferbeneficialinterestsinaglobalnotetopersonsthataresubjecttothoserequirementswillbelimitedtothatextent.BecauseDTCcanactonlyonbehalfofparticipants,whichinturnactonbehalfofindirectparticipants,theabilityofapersonhavingbeneficialinterestsinaglobalnotetopledgethoseintereststopersonsthatdonotparticipateintheDTCsystem,orotherwisetakeactionsinrespectofthoseinterests,maybeaffectedbythelackofaphysicalcertificateevidencingthoseinterests.

Exceptasdescribedbelow,ownersofaninterestinglobalnoteswillnothavenotesregisteredintheirnames,willnotreceivephysicaldeliveryofcertificatednotesandwillnotbeconsideredtheregisteredownersor"holders"thereofundertheindentureforanypurpose.

PaymentsinrespectoftheprincipalofandanypremiumandinterestonaglobalnoteregisteredinthenameofDTCoritsnomineewillbepayabletoDTCinitscapacityastheregisteredholderundertheindenture.Underthetermsoftheindenture,weandthetrusteewilltreatthepersonsinwhosenamesthenotes,includingglobalnotes,areregisteredastheownersofsuchnotesforthepurposeofreceivingpaymentsandforallotherpurposes.Consequently,neitherwe,thetrusteenoranyagentofusorthetrusteehasorwillhaveanyresponsibilityorliabilityfor:

(1)anyaspectofDTC'srecordsoranyparticipant'sorindirectparticipant'srecordsrelatingtoorpaymentsmadeonaccountofbeneficialownershipinterestsinglobalnotesorformaintaining,supervisingorreviewinganyofDTC'srecordsoranyparticipant'sorindirectparticipant'srecordsrelatingtothebeneficialownershipinterestsinglobalnotes;or

(2)anyothermatterrelatingtotheactionsandpracticesofDTCoranyofitsparticipantsorindirectparticipants.

DTChasadvisedusthatitscurrentpractice,uponreceiptofanypaymentinrespectofsecuritiessuchasthenotes(includingprincipalandinterest),istocredittheaccountsoftherelevantparticipantswiththepaymentonthepaymentdateunlessDTChasreasontobelieveitwillnotreceivepaymentonthatpaymentdate.EachrelevantparticipantiscreditedwithanamountproportionatetoitsbeneficialownershipofaninterestintheprincipalamountofnotesasshownontherecordsofDTC.Paymentsbytheparticipantsandtheindirectparticipantstothebeneficialownersofnoteswillbegovernedbystandinginstructionsandcustomarypracticesandwillbetheresponsibilityoftheparticipantsortheindirect

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participantsandwillnotbetheresponsibilityofDTC,thetrusteeorus.NeitherwenorthetrusteewillbeliableforanydelaybyDTCoranyofitsparticipantsinidentifyingthebeneficialownersofanynotes,andweandthetrusteemayconclusivelyrelyonandwillbeprotectedinrelyingoninstructionsfromDTCoritsnomineeforallpurposes.

TransfersbetweenparticipantsinDTCwillbeeffectedinaccordancewithDTC'sprocedures,andwillbesettledinsame-dayfunds.TransfersbetweenparticipantsinClearstreamandEuroclearwillbeeffectedinaccordancewiththeirrespectiverulesandoperatingprocedures.

Cross-markettransfersbetweentheparticipants,ontheonehand,andClearstreamorEuroclearparticipants,ontheotherhand,willbeeffectedthroughDTCinaccordancewithDTC'srulesonbehalfofClearstreamorEuroclear,asthecasemaybe,byitsrespectivedepositary;however,suchcross-markettransactionswillrequiredeliveryofinstructionstoClearstreamorEuroclear,asthecasemaybe,bythecounterpartyinsuchsysteminaccordancewiththerulesandproceduresandwithintheestablisheddeadlines(Brusselstime)ofsuchsystem.ClearstreamorEuroclear,asthecasemaybe,will,ifthetransactionmeetsitssettlementrequirements,deliverinstructionstoitsrespectivedepositarytotakeactiontoeffectfinalsettlementonitsbehalfbydeliveringorreceivinginterestsintherelevantglobalnotefromDTC,andmakingorreceivingpaymentinaccordancewithnormalproceduresforsame-dayfundssettlementapplicabletoDTC.ClearstreamparticipantsandEuroclearparticipantsmaynotdeliverinstructionsdirectlytothedepositoriesforClearstreamorEuroclear.

DTChasadvisedusthatitwilltakeanyactionpermittedtobetakenbyaholderofnotesonlyatthedirectionofoneormoreparticipantstowhoseaccountDTChascreditedtheinterestsintheglobalnotesandonlyinrespectoftheportionoftheaggregateprincipalamountofthenotesastowhichthatparticipantorthoseparticipantshasorhavegiventherelevantdirection.

AlthoughDTC,ClearstreamandEuroclearhaveagreedtotheforegoingproceduresinordertofacilitatetransfersofinterestsinglobalnotesamongparticipantsinDTC,ClearstreamandEuroclear,theyareundernoobligationtoperformthoseprocedures,andmaydiscontinueorchangethoseproceduresatanytime.Noneofus,thetrusteeoranyofourrespectiveagentswillhaveanyresponsibilityfortheperformancebyDTC,Clearstream,Euroclearortheirrespectiveparticipantsorindirectparticipantsoftheirrespectiveobligationsundertherulesandproceduresgoverningtheiroperations.

Same-DaySettlementandPayment

Wewillmakepaymentsinrespectofnotesrepresentedbyglobalnotes,includingpaymentsofprincipal,premium,ifany,andinterest,bywiretransferofimmediatelyavailablefundstotheaccountsspecifiedbyDTCoritsnominee.NotesrepresentedbyglobalnotesareexpectedtotradeinDTC'sSame-DayFundsSettlementSystem,andanypermittedsecondarymarkettradingactivityinnotesrepresentedbyglobalnoteswill,therefore,berequiredbyDTCtobesettledinimmediatelyavailablefunds.

Becauseoftimezonedifferences,thesecuritiesaccountofaClearstreamorEuroclearparticipantpurchasinganinterestinaglobalnotefromaparticipantwillbecredited,andanysuchcreditingwillbereportedtotherelevantClearstreamorEuroclearparticipant,duringthesecuritiessettlementprocessingday(whichmustbeabusinessdayforClearstreamandEuroclear)immediatelyfollowingthesettlementdateofDTC.DTChasadvisedusthatcashreceivedinClearstreamorEuroclearasaresultofsalesofinterestsinaglobalnotebyorthroughaClearstreamorEuroclearparticipanttoaparticipantwillbereceivedwithvalueon

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thesettlementdateofDTCbutwillbeavailableintherelevantClearstreamorEuroclearcashaccountonlyasofthebusinessdayforClearstreamorEuroclearfollowingDTC'ssettlementdate.

CertificatedNotes

Unlessanduntiltheyareexchanged,inwholeorinpart,forcertificatednotesinaccordancewiththetermsoftheindenture,thenotesmaynotbetransferredexcept(1)asawholebyDTCtoanomineeofDTC,(2)byanomineeofDTCtoDTCoranothernomineeofDTCor(3)byDTCoranysuchnomineetoasuccessorofDTCoranomineeofsuchsuccessor.

WewillissuecertificatednotestoeachpersonthatDTCidentifiesasthebeneficialownerofthenotesrepresentedbytheglobalnotesuponsurrenderbyDTCoftheglobalnotesif:

• DTCnotifiesusthatitisnolongerwillingorabletoactasadepositaryfortheglobalnotes,andwehavenotappointedasuccessordepositarywithin90daysofthatnotice;

• aneventofdefaulthasoccurredandiscontinuing,andDTCrequeststheissuanceofcertificatednotes;or

• wedeterminenottohavethenotesrepresentedbyaglobalnote.

NeitherwenorthetrusteewillbeliableforanydelaybyDTC,itsnomineeoranydirectorindirectparticipantinidentifyingthebeneficialownersoftherelatednotes.Weandthetrusteemayconclusivelyrelyon,andwillbeprotectedinrelyingon,instructionsfromDTCoritsnomineeforallpurposes,includingwithrespecttotheregistrationanddelivery,andtherespectiveprincipalamounts,ofthenotestobeissued.

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UNDERWRITING

DeutscheBankSecuritiesInc.andCitigroupGlobalMarketsInc.areactingasglobalcoordinatorsandbookrunnersoftheoffering.Subjecttothetermsandconditionsstatedintheunderwritingagreementdatedthedateofthisprospectussupplement,eachunderwriternamedbelowhasseverallyagreedtopurchase,andwehaveagreedtoselltothatunderwriter,theprincipalamountofnotessetforthoppositetheunderwriter'sname.

Theunderwritingagreementprovidesthattheobligationsoftheunderwriterstopurchasethenotesincludedinthisofferingaresubjecttoapprovaloflegalmattersbycounselandtootherconditions.Theunderwritersareobligatedtopurchaseallthenotesiftheypurchaseanyofthenotes.

Notessoldbytheunderwriterstothepublicwillinitiallybeofferedattheinitialpublicofferingpricessetforthonthecoverofthisprospectussupplement.Anynotessoldbytheunderwriterstosecuritiesdealersmaybesoldatadiscountfromtheinitialpublicofferingpricenottoexceed%pernote.Anysuchsecuritiesdealersmayresellanynotespurchasedfromtheunderwriterstocertainotherbrokersordealersatadiscountfromtheinitialpublicofferingpricenottoexceed%pernote.Ifallthenotesarenotsoldattheinitialofferingprice,theunderwritersmaychangetheofferingpriceandtheothersellingterms.Theunderwritersalsoreservetherighttowithdraw,cancelormodifyofferstothepublicandtorejectordersinwholeorinpart.

Wehaveagreedthat,duringtheperiodcommencingonthedateofthisprospectussupplementandendingonthebusinessdayafterthenotesareissued,wewillnot,withoutthepriorwrittenconsentofDeutscheBankSecuritiesInc.,offer,sell,contracttosell,pledge,orotherwisedisposeof(orenterintoanytransactionwhichisdesignedto,ormightreasonablybeexpectedto,resultinthedisposition(whetherbyactualdispositionoreffectiveeconomicdispositionduetocashsettlementorotherwise)byusoranyofouraffiliatesoranypersoninprivitywithusoranyofouraffiliates),directlyorindirectly,includingthefiling(orparticipationinthefiling)ofaregistrationstatementwiththeSECinrespectof,orestablishorincreaseaputequivalentpositionorliquidateordecreaseacallequivalentpositionwithinthemeaningofSection16oftheExchangeAct,anydebtsecuritiesissuedorguaranteedbyus(otherthanthenotes)orpubliclyannounceanintentiontoeffectanysuchtransaction.

Wearetopaytotheunderwritersanunderwritingdiscountof%inconnectionwiththisoffering(expressedasapercentageoftheprincipalamountofthenotes).

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Underwriters PrincipalAmountof

Notes DeutscheBankSecuritiesInc. CitigroupGlobalMarketsInc. BNPParibasSecuritiesCorp. DNBMarkets,Inc. HSBCSecurities(USA)Inc. MerrillLynch,Pierce,Fenner&SmithIncorporated

MorganStanley&Co.LLC SkandinaviskaEnskildaBankenAB Total $ 500,000,000

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Weestimatethatourtotalexpensesforthisofferingwillbeapproximately$million.

Thenotesareanewissueofsecurities,andthereisnopublictradingmarketforthenotes.WeareapplyingforlistingofthenotesontheNYSE;however,wecangivenoassurancesthatthenoteswillbesolisted.Theunderwritershaveinformedusthattheyintendtomakeamarketinthenotes.However,theunderwritersmayceasetheirmarket-makingatanytime.Theliquidityofthetradingmarketsinthenotesandthemarketpricesquotedforthenotesmaybeadverselyaffectedbychangesintheoverallmarketfordebtsecuritiesandbychangesinourfinancialperformanceorprospectsorintheprospectsforcompaniesinourindustriesgenerally.Asaconsequence,anactivetradingmarketmaynotdeveloporbemaintainedforyournotes,youmaynotbeabletosellyournotes,or,evenifyoucansellyournotes,youmaynotbeabletosellthematanacceptableprice.

Inconnectionwiththeoffering,theunderwritersmaypurchaseandsellnotesintheopenmarket.Purchasesandsalesintheopenmarketmayincludeshortsales,purchasestocovershortpositionsandstabilizingpurchases.

• Shortsalesinvolvesecondarymarketsalesbytheunderwritersofagreaternumberofnotesthantheyarerequiredtopurchaseintheoffering.

• Coveringtransactionsinvolvepurchasesofnotesintheopenmarketafterthedistributionhasbeencompletedinordertocovershortpositions.

• Stabilizingtransactionsinvolvebidstopurchasenotessolongasthestabilizingbidsdonotexceedaspecifiedmaximum.

Purchasestocovershortpositionsandstabilizingpurchases,aswellasotherpurchasesbytheunderwritersfortheirownaccounts,mayhavetheeffectofpreventingorretardingadeclineinthemarketpriceofthenotes.Theymayalsocausethepriceofthenotestobehigherthanthepricethatwouldotherwiseexistintheopenmarketintheabsenceofthesetransactions.Theunderwritersmayconductthesetransactionsintheover-the-countermarketorotherwise.Iftheunderwriterscommenceanyofthesetransactions,theymaydiscontinuethematanytime.

Weexpectdeliveryofthenoteswillbemadeagainstpaymentthereforonorabout,2018,whichisthetenthbusinessdayfollowingthedateofpricingofthenotes(suchsettlementbeingreferredtoas"T+10").UnderRule15c6-1oftheSecuritiesExchangeActof1934,asamended,tradesinthesecondarymarketgenerallyarerequiredtosettleintwobusinessdaysunlessthepartiestoanysuchtradeexpresslyagreeotherwise.Accordingly,purchaserswhowishtotradethenotesonthedateofpricingofthenotesorthesucceedingeightbusinessdayswillberequired,byvirtueofthefactthatthenotesinitiallywillsettleinT+10,tospecifyanalternatesettlementcycleatthetimeofanysuchtradetopreventfailedsettlementandshouldconsulttheirownadvisers.

Theunderwritersarefullservicefinancialinstitutionsengagedinvariousactivities,whichmayincludesecuritiestrading,commercialandinvestmentbanking,financialadvisory,investmentmanagement,principalinvestment,hedging,financingandbrokerageactivities.Theunderwritersandtheirrespectiveaffiliateshaveinthepastperformedcommercialbanking,investmentbankingandadvisoryservicesforusfromtimetotimeforwhichtheyhavereceivedcustomaryfeesandreimbursementofexpensesandmay,fromtimetotime,engageintransactionswithandperformservicesforusintheordinarycourseoftheirbusinessforwhichtheymayreceivecustomaryfeesandreimbursementofexpenses.Intheordinarycourseoftheirvariousbusinessactivities,theunderwritersandtheirrespectiveaffiliatesmaymakeorholdabroadarrayofinvestmentsandactivelytradedebtandequity

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securities(orrelatedderivativesecurities)andfinancialinstruments(whichmayincludebankloansand/orcreditdefaultswaps)fortheirownaccountandfortheaccountsoftheircustomersandmayatanytimeholdlongandshortpositionsinsuchsecuritiesandinstruments.Suchinvestmentandsecuritiesactivitiesmayinvolveoursecuritiesandinstruments.Certainoftheunderwritersandtheirrespectiveaffiliatesmayholdpositionsinouroutstandingnotes,includingtherepurchasenotes,andthereforemayreceiveaportionofthenetproceedsfromthisofferingifweredeemanyofthosenotesorpurchaseanyoftherepurchasenotespursuanttothetenderoffers.See"UseofProceeds."Certainoftheunderwritersortheiraffiliatesthathavealendingrelationshipwithusroutinelyhedge,andcertainotheroftheunderwritersortheiraffiliatesthathavealendingrelationshipwithusmayhedge,theircreditexposuretousconsistentwiththeircustomaryriskmanagementpolicies.Typically,suchunderwritersandtheiraffiliateswouldhedgesuchexposurebyenteringintotransactionswhichconsistofeitherthepurchaseofcreditdefaultswapsorthecreationofshortpositionsinoursecurities,includingpotentiallythenotesofferedhereby.Anysuchcreditdefaultswapsorshortpositionscouldadverselyaffectfuturetradingpricesofthenotesofferedhereby.Inaddition,affiliatesofsomeoftheunderwritersarelenders,andinsomecasesagentsormanagersforthelenders,underourrevolvingcreditfacility.DeutscheBankTrustCompanyAmericas,thetrusteeforthenotes,isanaffiliateofDeutscheBankSecuritiesInc.DeutscheBankSecuritiesInc.,BNPParibasSecuritiesCorp.,DNBMarkets,Inc.,HSBCSecurities(USA)Inc.,MerrillLynch,Pierce,Fenner&SmithIncorporated,MorganStanley&Co.LLCandSkandinaviskaEnskildaBankenABarethedealermanagersforthetenderoffers.

Wehaveagreedtoindemnifytheunderwritersagainstcertainliabilities,includingliabilitiesundertheSecuritiesActof1933,ortocontributetopaymentstheunderwritersmayberequiredtomakebecauseofanyofthoseliabilities.

NoticetoProspectiveInvestorsinCanada

Thenotesmaybesoldonlytopurchaserspurchasing,ordeemedtobepurchasing,asprincipalthatareaccreditedinvestors,asdefinedinNationalInstrument45-106ProspectusExemptionsorsubsection73.3(1)oftheSecuritiesAct(Ontario),andarepermittedclients,asdefinedinNationalInstrument31-103RegistrationRequirements,ExemptionsandOngoingRegistrantObligations.Anyresaleofthenotesmustbemadeinaccordancewithanexemptionfrom,orinatransactionnotsubjectto,theprospectusrequirementsofapplicablesecuritieslaws.

SecuritieslegislationincertainprovincesorterritoriesofCanadamayprovideapurchaserwithremediesforrescissionordamagesifthisprospectussupplement(includinganyamendmentthereto)containsamisrepresentation,providedthattheremediesforrescissionordamagesareexercisedbythepurchaserwithinthetimelimitprescribedbythesecuritieslegislationofthepurchaser'sprovinceorterritory.Thepurchasershouldrefertoanyapplicableprovisionsofthesecuritieslegislationofthepurchaser'sprovinceorterritoryforparticularsoftheserightsorconsultwithalegaladvisor.

Pursuanttosection3A.3ofNationalInstrument33-105UnderwritingConflicts(NI33-105),theunderwritersarenotrequiredtocomplywiththedisclosurerequirementsofNI33-105regardingunderwriterconflictsofinterestinconnectionwiththisoffering.

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NoticetoProspectiveInvestorsintheEuropeanEconomicArea

InrelationtoeachmemberstateoftheEuropeanEconomicArea,noofferofnoteswhicharethesubjectoftheofferinghasbeen,orwillbemadetothepublicinthatMemberState,otherthanunderthefollowingexemptionsundertheProspectusDirective:

A.toanylegalentitywhichisaqualifiedinvestorasdefinedintheProspectusDirective;

B.tofewerthan150naturalorlegalpersons(otherthanqualifiedinvestorsasdefinedintheProspectusDirective),subjecttoobtainingthepriorconsentoftheRepresentativesforanysuchoffer;or

C.inanyothercircumstancesfallingwithinArticle3(2)oftheProspectusDirective,

providedthatnosuchofferofnotesreferredtoin(A)to(C)aboveshallresultinarequirementfortheCompanyoranyunderwritertopublishaprospectuspursuanttoArticle3oftheProspectusDirectiveorsupplementaprospectuspursuanttoArticle16oftheProspectusDirective.

ThisprospectussupplementandtheaccompanyingprospectushavebeenpreparedonthebasisthatanyofferofnotesinanyMemberStatewillbemadepursuanttoanexemptionundertheProspectusDirectivefromtherequirementtopublishaprospectusforoffersofnotes.AccordinglyanypersonmakingorintendingtomakeanofferinthatRelevantMemberStateofnoteswhicharethesubjectoftheofferingcontemplatedinthisprospectussupplementandtheaccompanyingprospectusmayonlydosoincircumstancesinwhichnoobligationarisesfortheCompanyoranyoftheunderwriterstopublishaprospectuspursuanttoArticle3oftheProspectusDirectiveinrelationtosuchoffer.NeithertheCompanynortheunderwritershaveauthorized,nordotheyauthorize,themakingofanyofferofnotesincircumstancesinwhichanobligationarisesfortheCompanyortheunderwriterstopublishaprospectusforsuchoffer.

Forthepurposeofthisprovision,theexpressionan"offerofnotestothepublic"inrelationtoanynotesinanyMemberStatemeansthecommunicationinanyformandbyanymeansofsufficientinformationonthetermsoftheofferandthenotestobeofferedsoastoenableaninvestortodecidetopurchaseorsubscribethenotes,asthesamemaybevariedinthatMemberStatebyanymeasureimplementingtheProspectusDirectiveinthatMemberStateandtheexpression"ProspectusDirective"meansDirective2003/71/EC(asamended)andincludesanyrelevantimplementingmeasureintheeachMemberState.

Thenotesarenotintendedtobeoffered,soldorotherwisemadeavailabletoandshouldnotbeoffered,soldorotherwisemadeavailabletoanyretailinvestorintheEuropeanEconomicArea.Forthesepurposes,(a)aretailinvestormeansapersonwhoisone(ormore)of:(i)aretailclientasdefinedinpoint(11)ofArticle4(1)ofDirective2014/65/EU(asamended,"MiFIDII");or(ii)acustomerwithinthemeaningofDirective2002/92/EC(asamended,the"InsuranceMediationDirective"),wherethatcustomerwouldnotqualifyasaprofessionalclientasdefinedinpoint(10)ofArticle4(1)ofMiFIDII;or(iii)notaqualifiedinvestorasdefinedinDirective2003/71/EC(asamended,the"ProspectusDirective");and(b)theexpression"offer"includesthecommunicationinanyformandbyanymeansofsufficientinformationonthetermsoftheofferandthenotestobeofferedsoastoenableaninvestortodecidetopurchaseorsubscribethenotes.ConsequentlynokeyinformationdocumentrequiredbyRegulation(EU)No1286/2014(asamended,the"PRIIPsRegulation")forofferingorsellingthenotesorotherwisemakingthemavailabletoretailinvestorsintheEuropeanEconomicAreahasbeenpreparedandthereforeofferingorsellingthenotesor

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otherwisemakingthemavailabletoanyretailinvestorintheEuropeanEconomicAreamaybeunlawfulunderthePRIIPSRegulation.

Solelyforthepurposesofeachmanufacturer'sproductapprovalprocess,thetargetmarketassessmentinrespectofthenoteshasledtotheconclusionthat(i)thetargetmarketforthenotesiseligiblecounterpartiesandprofessionalclientsonly,eachasdefinedinMiFIDII;and(ii)allchannelsfordistributionofthenotestoeligiblecounterpartiesandprofessionalclientsareappropriate.Anypersonsubsequentlyoffering,sellingorrecommendingthenotes(a"distributor")shouldtakeintoconsiderationthemanufacturers'targetmarketassessment;however,adistributorsubjecttoMiFIDIIisresponsibleforundertakingitsowntargetmarketassessmentinrespectofthenotes(byeitheradoptingorrefiningthemanufacturers'targetmarketassessment)anddeterminingappropriatedistributionchannels.

NoticetoProspectiveInvestorsintheUnitedKingdom

Thisprospectussupplementandtheaccompanyingprospectusareonlybeingdistributedto,andareonlydirectedat,personsintheUnitedKingdomthatarequalifiedinvestorswithinthemeaningofArticle2(1)(e)oftheProspectusDirectivethatarealso(i)investmentprofessionalsfallingwithinArticle19(5)oftheFinancialServicesandMarketsAct2000(FinancialPromotion)Order2005(the"Order")or(ii)highnetworthentities,andotherpersonstowhomitmaylawfullybecommunicated,fallingwithinArticle49(2)(a)to(d)oftheOrder(eachsuchpersonbeingreferredtoasa"relevantperson").Thisprospectussupplementanditscontentsareconfidentialandshouldnotbedistributed,publishedorreproduced(inwholeorinpart)ordisclosedbyrecipientstoanyotherpersonsintheUnitedKingdom.AnypersonintheUnitedKingdomthatisnotarelevantpersonshouldnotactorrelyonthisdocumentoranyofitscontents.

Eachunderwriterhasrepresentedandagreedthat:

(a) ithascommunicatedorcausedtobecommunicatedandwillcommunicateorcausetobecommunicatedaninvitationorinducementtoengageininvestmentactivity(withinthemeaningofSection21oftheFinanceServiceandMarketAct2000("FSMA"))receivedbyitinconnectionwiththeissueorsaleofthenotesonlyincircumstancesinwhichSection21(1)oftheFSMAdoesnotapplytous;and

(b) ithascompliedandwillcomplywithallapplicableprovisionsoftheFSMAwithrespecttoanythingdonebyitinrelationtothenotesin,fromorotherwiseinvolvingtheUnitedKingdom.

NoticetoProspectiveInvestorsinFrance

NeitherthisprospectussupplementnoranyotherofferingmaterialrelatingtothenotesdescribedinthisprospectussupplementhasbeensubmittedtotheclearanceproceduresoftheAutoritédesMarchésFinanciersorofthecompetentauthorityofanothermemberstateoftheEuropeanEconomicAreaandnotifiedtotheAutoritédesMarchésFinanciers.Thenoteshavenotbeenofferedorsoldandwillnotbeofferedorsold,directlyorindirectly,tothepublicinFrance.Neitherthisprospectussupplementnoranyotherofferingmaterialrelatingtothenoteshasbeenorwillbe:

• released,issued,distributedorcausedtobereleased,issuedordistributedtothepublicinFrance;or

• usedinconnectionwithanyofferforsubscriptionorsaleofthenotestothepublicinFrance.

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Suchoffers,salesanddistributionswillbemadeinFranceonly:

• toqualifiedinvestors(investisseursqualifiés)and/ortoarestrictedcircleofinvestors(cerclerestreintd'investisseurs),ineachcaseinvestingfortheirownaccount,allasdefinedin,andinaccordancewith,articlesL.411-2,D.411-1,D.411-2,D.734-1,D.744-1,D.754-1andD.764-1oftheFrenchCodemonétaireetfinancier;

• toinvestmentservicesprovidersauthorizedtoengageinportfoliomanagementonbehalfofthirdparties;or

• inatransactionthat,inaccordancewitharticleL.411-2-II-1°-or-2°-or3°oftheFrenchCodemonétaireetfinancierandarticle211-2oftheGeneralRegulations(RèglementGénéral)oftheAutoritédesMarchésFinanciers,doesnotconstituteapublicoffer(appelpublicàl'épargne).

Thenotesmayberesold,directlyorindirectly,onlyincompliancewitharticlesL.411-1,L.411-2,L.412-1andL.621-8throughL.621-8-3oftheFrenchCodemonétaireetfinancier.

NoticetoProspectiveInvestorsinHongKong

ThenotesmaynotbeofferedorsoldinHongKongbymeansofanydocumentotherthan(i)incircumstanceswhichdonotconstituteanoffertothepublicwithinthemeaningoftheCompaniesOrdinance(Cap.32,LawsofHongKong),or(ii)to"professionalinvestors"withinthemeaningoftheSecuritiesandFuturesOrdinance(Cap.571,LawsofHongKong)andanyrulesmadethereunder,or(iii)inothercircumstanceswhichdonotresultinthedocumentbeinga"prospectus"withinthemeaningoftheCompaniesOrdinance(Cap.32,LawsofHongKong)andnoadvertisement,invitationordocumentrelatingtothenotesmaybeissuedormaybeinthepossessionofanypersonforthepurposeofissue(ineachcasewhetherinHongKongorelsewhere),whichisdirectedat,orthecontentsofwhicharelikelytobeaccessedorreadby,thepublicinHongKong(exceptifpermittedtodosounderthelawsofHongKong)otherthanwithrespecttonoteswhichareorareintendedtobedisposedofonlytopersonsoutsideHongKongoronlyto"professionalinvestors"withinthemeaningoftheSecuritiesandFuturesOrdinance(Cap.571,LawsofHongKong)andanyrulesmadethereunder.

NoticetoProspectiveInvestorsinJapan

ThenoteshavenotbeenandwillnotberegisteredundertheFinancialInstrumentsandExchangeLawofJapan(the"FinancialInstrumentsandExchangeLaw")andeachunderwriterhasagreedthatitwillnotofferorsellanynotes,directlyorindirectly,inJapanorto,orforthebenefitof,anyresidentofJapan(whichtermasusedhereinmeansanypersonresidentinJapan,includinganycorporationorotherentityorganizedunderthelawsofJapan),ortoothersforre-offeringorresale,directlyorindirectly,inJapanortoaresidentofJapan,exceptpursuanttoanexemptionfromtheregistrationrequirementsof,andotherwiseincompliancewith,theFinancialInstrumentsandExchangeLawandanyotherapplicablelaws,regulationsandministerialguidelinesofJapan.

NoticetoProspectiveInvestorsinSingapore

ThisprospectussupplementhasnotbeenregisteredasaprospectuswiththeMonetaryAuthorityofSingapore.Accordingly,thisprospectussupplementandanyotherdocumentormaterialinconnectionwiththeofferorsale,orinvitationforsubscriptionorpurchase,ofthenotesmaynotbecirculatedordistributed,normaythenotesbeofferedorsold,orbemadethesubjectofaninvitationforsubscriptionorpurchase,whetherdirectlyorindirectly,to

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personsinSingaporeotherthan(i)toaninstitutionalinvestorunderSection274oftheSecuritiesandFuturesAct,Chapter289ofSingapore(the"SFA"),(ii)toarelevantpersonpursuanttoSection275(1),oranypersonpursuanttoSection275(1A),andinaccordancewiththeconditionsspecifiedinSection275oftheSFAor(iii)otherwisepursuantto,andinaccordancewiththeconditionsof,anyotherapplicableprovisionoftheSFA,ineachcasesubjecttocompliancewithconditionssetforthintheSFA.

WherethenotesaresubscribedorpurchasedunderSection275oftheSFAbyarelevantpersonwhichis:

• acorporation(whichisnotanaccreditedinvestor(asdefinedinSection4AoftheSFA))thesolebusinessofwhichistoholdinvestmentsandtheentiresharecapitalofwhichisownedbyoneormoreindividuals,eachofwhomisanaccreditedinvestor;or

• atrust(wherethetrusteeisnotanaccreditedinvestor)whosesolepurposeistoholdinvestmentsandeachbeneficiaryofthetrustisanindividualwhoisanaccreditedinvestor,shares,debenturesandunitsofsharesanddebenturesofthatcorporationorthebeneficiaries'rightsandinterest(howsoeverdescribed)inthattrustshallnotbetransferredwithinsixmonthsafterthatcorporationorthattrusthasacquiredthenotespursuanttoanoffermadeunderSection275oftheSFAexcept:

• toaninstitutionalinvestor(forcorporations,underSection274oftheSFA)ortoarelevantpersondefinedinSection275(2)oftheSFA,ortoanypersonpursuanttoanofferthatismadeontermsthatsuchshares,debenturesandunitsofsharesanddebenturesofthatcorporationorsuchrightsandinterestinthattrustareacquiredataconsiderationofnotlessthanS$200,000(oritsequivalentinaforeigncurrency)foreachtransaction,whethersuchamountistobepaidforincashorbyexchangeofsecuritiesorotherassets,andfurtherforcorporations,inaccordancewiththeconditionsspecifiedinSection275oftheSFA;

• wherenoconsiderationisorwillbegivenforthetransfer;

• wherethetransferisbyoperationoflaw;

• asspecifiedinSection276(7)oftheSFA;or

• asspecifiedinRegulation32oftheSecuritiesandFutures(OffersofInvestments)(SharesandDebentures)Regulations2005ofSingapore.

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LEGALMATTERS

ThevalidityofthenotesandcertainothermatterswithrespecttothisofferingarebeingpasseduponforusbyGibson,Dunn&CrutcherLLP.CertainlegalmattersofNewYorklawwithrespecttothisofferingwillbepasseduponfortheunderwritersbyDavisPolk&WardwellLLP.

EXPERTS

TheconsolidatedfinancialstatementsofEnscoplcandsubsidiariesasofDecember31,2016and2015,andforeachoftheyearsinthethree-yearperiodendedDecember31,2016,andmanagement'sassessmentoftheeffectivenessofinternalcontroloverfinancialreportingasofDecember31,2016havebeenincorporatedbyreferenceinthisprospectussupplementinrelianceuponthereportsofKPMGLLP,independentregisteredpublicaccountingfirm,incorporatedbyreferenceherein,andupontheauthorityofsaidfirmasexpertsinaccountingandauditing.

WithrespecttotheunauditedinterimfinancialinformationfortheperiodsendedMarch31,2017,June30,2017,andSeptember30,2017,incorporatedbyreferenceherein,theindependentregisteredpublicaccountingfirmhasreportedthattheyappliedlimitedproceduresinaccordancewithprofessionalstandardsforareviewofsuchinformation.However,theirseparatereportsincludedintheCompany'squarterlyreportsonForm10-QforthequarterendedMarch31,2017,June30,2017,andSeptember30,2017,andincorporatedbyreferenceherein,statesthattheydidnotauditandtheydonotexpressanopiniononthatinterimfinancialinformation.Accordingly,thedegreeofrelianceontheirreportonsuchinformationshouldberestrictedinlightofthelimitednatureofthereviewproceduresapplied.TheaccountantsarenotsubjecttotheliabilityprovisionsofSection11oftheSecuritiesActfortheirreportontheunauditedinterimfinancialinformationbecausethatreportisnota"report"ora"part"oftheregistrationstatementpreparedorcertifiedbytheaccountantswithinthemeaningofSections7and11oftheSecuritiesAct.

TheauditedhistoricalfinancialstatementsofAtwoodOceanics,Inc.andmanagement'sassessmentoftheeffectivenessofinternalcontroloverfinancialreportingincludedinexhibit99.2ofEnscoplc'sCurrentReportonForm8-K/AdatedDecember15,2017havebeensoincorporatedinrelianceonthereportofPricewaterhouseCoopersLLP,anindependentregisteredpublicaccountingfirm,givenontheauthorityofsaidfirmasexpertsinauditingandaccounting.

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PROSPECTUS

EnscoplcDebtSecurities

ClassAOrdinarySharesPreferenceSharesOrdinaryShares

WarrantsSharePurchaseContracts

GuaranteesUnits

From time to time, we may offer to sell debt securities, Class A Ordinary Shares, preference shares, ordinary shares, warrants, share purchase contracts andguarantees, as well as units that include any of these securities or securities of other entities. The debt securities, preference shares, warrants and share purchasecontracts may be convertible into or exercisable or exchangeable for Class A Ordinary Shares, ordinary shares or preference shares or other securities of ourcompany or debt or equity securities of one or more other entities.

We may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis.If any underwriters, dealers or agents are involved in the sale of any of the securities, their names and any applicable purchase price, fee, commission or discountarrangement between or among them will be set forth in, or will be calculable from the information set forth in, the applicable prospectus supplement. See thesections of this prospectus entitled "About this Prospectus" and "Plan of Distribution" for more information. No securities may be sold without delivery of thisprospectus and the applicable prospectus supplement describing the method and terms of the offering of such series of securities.

This prospectus describes some of the general terms that may apply to these securities. The specific terms of any securities to be offered will be described in asupplement to this prospectus.

Our Class A Ordinary Shares trade on the New York Stock Exchange under the symbol "ESV".

Investinginoursecuritiesinvolvesrisk.Youshouldcarefullyreviewtherisksanduncertaintiesdescribedundertheheading"RiskFactors"containedonpage3hereinandintheapplicableprospectussupplementandanyrelatedfreewritingprospectusandundersimilarheadingsintheotherdocumentsincorporatedbyreferenceintothisprospectus.

NeithertheSecuritiesandExchangeCommissionnoranystatesecuritiescommissionhasapprovedordisapprovedofthesesecuritiesordeterminedifthisprospectusistruthfulorcomplete.Anyrepresentationtothecontraryisacriminaloffense.

The date of this prospectus is November 21, 2017.

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i

ABOUT THIS PROSPECTUS 1

WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE

1

FORWARD-LOOKING INFORMATION

2

RISK FACTORS

3

THE COMPANY

3

USE OF PROCEEDS

4

RATIO OF EARNINGS TO FIXED CHARGES

4

DESCRIPTION OF DEBT SECURITIES

4

DESCRIPTION OF CLASS A ORDINARY SHARES

5

DESCRIPTION OF PREFERENCE SHARES AND ORDINARY SHARES

5

DESCRIPTION OF WARRANTS

5

DESCRIPTION OF SHARE PURCHASE CONTRACTS

6

DESCRIPTION OF GUARANTEES

6

DESCRIPTION OF UNITS

7

PLAN OF DISTRIBUTION

7

LEGAL MATTERS

7

EXPERTS

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ABOUTTHISPROSPECTUS

This prospectus is part of a registration statement that we have filed with the Securities and Exchange Commission (the "SEC") using a "shelf" registrationprocess. Under this shelf registration process, we may sell any combination of the securities described in this prospectus in one or more offerings.

As used in this prospectus, unless we state otherwise or the context indicates otherwise, references to "Ensco," the "Company," "we," "us" or "our" refer toEnsco plc and its subsidiaries. In the sections "Descriptions of Debt Securities," "Description of Preference Shares and Ordinary Shares," "Description ofWarrants," "Description of Share Purchase Contracts," "Description of Guarantees" and "Description of Units," references to "Ensco," the "company," "we," "us"or "our" refer only to Ensco plc and not to any of our subsidiaries.

This prospectus provides a general description of the securities offered by us. Each time we sell securities, we will provide a prospectus supplement that willcontain specific information about the terms of that offering and the securities being offered. The prospectus supplement may also add to, update or changeinformation contained in this prospectus and, accordingly, to the extent inconsistent, information in this prospectus shall be superseded by the information in theprospectus supplement. You should read both this prospectus and any prospectus supplement together with additional information described under the heading"Where You Can Find More Information; Incorporation by Reference."

The prospectus supplement to be attached to the front of this prospectus may describe, as applicable: the terms of the securities offered, the initial publicoffering price, the price paid for the securities, net proceeds and the other specific terms related to the offering of these securities.

You should rely only on the information contained or incorporated by reference in this prospectus and any prospectus supplement. We have not authorizedany other person to provide different information. If anyone provides you different or inconsistent information, you should not rely on it. We are not making offersto sell these securities in any jurisdiction where the offer or sale is not permitted. For the avoidance of doubt, this prospectus is not intended to be and is not aprospectus for purposes of the E.U. Prospectus Directive and/or the U.K. Financial Conduct Authority's Prospectus Rules. You should assume that the informationcontained or incorporated by reference in this prospectus or any prospectus supplement is accurate only as of the respective dates thereof or, in the case ofinformation incorporated by reference, only as of the date of such information, regardless of the time of delivery of this prospectus or any prospectus supplement.Our business, financial condition, results of operations and prospects may have changed since such dates.

WHEREYOUCANFINDMOREINFORMATION;INCORPORATIONBYREFERENCE

We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any reports, statements or otherinformation on file at the SEC's public reference room at 100 F Street, N.E., Washington, D.C., 20549. Please call the SEC at 1-800-SEC-0330 for furtherinformation on the public reference room. Our SEC filings are also available to the public from commercial document retrieval services and are available at theInternet website maintained by the SEC at http://www.sec.gov. These reports and other information filed by us with the SEC are also available free of charge at ourwebsite at www.enscoplc.com.

We incorporate information into this prospectus by reference, which means that we disclose important information to you by referring you to anotherdocument filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, except to the extent superseded byinformation contained herein or by information contained in documents filed with the SEC after the date of this prospectus. This prospectus incorporates byreference the documents set

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forth below that have been previously filed with the SEC. These documents contain important information about us and our financial condition.

Ensco SEC Filings

• Ensco's Annual Report on Form 10-K for the year ended December 31, 2016 (the "Form 10-K");

• Ensco's Quarterly Reports on Form 10-Q for the quarters ended March 31, 2017, June 30, 2017 and September 30, 2017;

• The information included in Ensco's Definitive Proxy Statement on Schedule 14A filed on March 31, 2017 to the extent incorporated by referencein Part III of the Form 10-K;

• Ensco's Current Reports on Form 8-K filed January 11, 2017, January 23, 2017, March 10, 2017, May 23, 2017, May 30, 2017, July 27, 2017,September 28, 2017, October 5, 2017, October 6, 2017, October 13, 2017 and October 25, 2017; and

• The description of Ensco's Class A Ordinary Shares contained in Ensco's Current Report on Form 8-K filed December 23, 2009, as amended andsuperseded by the description set forth in the Current Report on Form 8-K filed May 15, 2012, as Ensco may update that description from time totime.

We also incorporate by reference into this prospectus additional documents that Ensco may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of theSecurities Exchange Act of 1934 from the date of this prospectus to the completion of the offering of the securities. These documents may include Annual Reportson Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as proxy statements. We are not incorporating by reference anyinformation furnished under items 2.02 or 7.01 (or corresponding information furnished under item 9.01 or included as an exhibit) in any past or future CurrentReport on Form 8-K that we may file with the SEC, unless otherwise specified in such Current Report.

You may obtain copies of any of these filings as described below, through the SEC or through the SEC's Internet website as described above or through ourwebsite as described above. Documents incorporated by reference are available without charge, excluding all exhibits unless an exhibit has been specificallyincorporated by reference into this prospectus, by requesting them in writing or by telephone at:

Investor Relations Ensco plc

5847 San Felipe, Suite 3300 Houston, Texas 77057

(713) 789-1400

THE INFORMATION CONTAINED IN OUR WEBSITE IS NOT INCORPORATED BY REFERENCE AND DOES NOT CONSTITUTE A PART OFTHIS PROSPECTUS.

FORWARD-LOOKINGINFORMATION

The information contained in this prospectus is accurate only as of the date hereof.

This prospectus and the documents incorporated herein by reference contain some forward-looking statements that set forth anticipated results based onmanagement's plans and assumptions. From time to time, we also provide forward-looking statements in other materials we release to the public, as well as oralforward-looking statements. Such statements give our current expectations or forecasts of future events; they do not relate strictly to historical or current facts. Wehave tried, wherever possible, to

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identify such statements by using words such as "anticipate," "estimate," "expect," "project," "intend," "plan," "believe," "will," "target," "forecast" and similarexpressions in connection with any discussion of future operating or financial performance or business plans or prospects. In particular, these include statementsrelating to future actions, business plans and prospects, future performance or results of current and anticipated products, expenses, interest rates, foreign exchangerates, the outcome of contingencies, such as legal proceedings, and financial results.

We cannot guarantee that any forward-looking statement will be realized. Achievement of future results is subject to risks, uncertainties and potentiallyinaccurate assumptions, including, but not limited to, the risks and uncertainties described under "Risk Factors" below and in our most recent Annual Report onForm 10-K and our subsequently filed Quarterly Reports on Form 10-Q. Should known or unknown risks or uncertainties materialize, or should underlyingassumptions prove inaccurate, actual results could differ materially from past results and those anticipated, estimated or projected. You should bear this in mind asyou consider forward-looking statements.

You should take care not to place undue reliance on forward-looking statements, which represent our views only as of the date they are made.

We undertake no obligation to publicly update or revise forward-looking statements, whether as a result of new information, future events or otherwise,except as required by law. You are advised, however, to consult any further disclosures we make on related subjects in our Annual Reports on Form 10-K, ourQuarterly Reports on Form 10-Q and Current Reports on Form 8-K filed with the SEC.

RISKFACTORS

Investing in our securities involves significant risks. Before making an investment decision, you should carefully consider the risks and other information weinclude or incorporate by reference in this prospectus. In particular, you should consider the risk factors set forth in our most recent Annual Report on Form 10-Kfiled with the SEC, as those risk factors are amended or supplemented by subsequent Quarterly Reports on Form 10-Q and other reports and documents we filewith the SEC after the date of this prospectus that are incorporated by reference herein. The risks and uncertainties we have described are not the only ones facingus. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations. Additional riskfactors may be included in a prospectus supplement relating to a particular series or offering of securities.

THECOMPANY

Ensco is a global offshore contract drilling company and one of the leading providers of offshore contract drilling services to the international oil and gasindustry. On October 6, 2017, we acquired Atwood Oceanics, Inc. As a result, we currently own and operate an offshore drilling rig fleet of 62 rigs, with drillingoperations in most of the strategic markets around the globe. We also have three rigs under construction. Our rig fleet consists of 12 drillships, 11 dynamicallypositioned semisubmersible rigs, four moored semisubmersible rigs and 38 jackup rigs. Our offshore rig fleet is one of the world's largest amongst competitiverigs, including one of the newest ultra-deepwater fleets in the industry and a leading premium jackup fleet.

Our registered office (which is our principal executive office) is located at 6 Chesterfield Gardens, 3rd Floor, London, United Kingdom W1J 5BQ, and ourtelephone number is +44 (0) 20 7659 4660. We are registered in England and Wales under company number 7023598. Our website is locatedat www.enscoplc.com. The information on or linked to/from our website is not part of, and is not incorporated by reference into, this prospectus.

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USEOFPROCEEDS

We intend to use the net proceeds from the sales of the securities for general corporate purposes unless otherwise set forth in the applicable prospectussupplement.

RATIOOFEARNINGSTOFIXEDCHARGES

For the purpose of computing the ratio of earnings to fixed charges, "earnings" consist of income from continuing operations before income taxes, fixedcharges and amortization of capitalized interest, less income from continuing operations before income taxes attributable to non-controlling interests and interestcapitalized. "Fixed charges" consist of interest expensed and capitalized and estimates of interest within rental expense. The ratios were calculated by dividing thesum of the fixed charges into the sum of the earnings. Our consolidated ratio of earnings to fixed charges for each of the fiscal years ended December 31, 2012through 2016 and the nine months ended September 30, 2017 are set forth below:

We had no preferred stock outstanding for any period presented, and accordingly, the ratio of combined fixed charges and preferred stock dividends toearnings is the same as the ratio of earnings to fixed charges for those periods.

DESCRIPTIONOFDEBTSECURITIES

The debt securities we may offer pursuant to this prospectus will be general unsecured obligations of Ensco plc and will be senior, senior subordinated orsubordinated debt. Our unsecured senior debt securities will be issued under the indenture dated as of March 17, 2011 between us and Deutsche Bank TrustCompany Americas, as trustee. The unsecured senior subordinated debt securities will be issued under a separate indenture to be entered into by us and DeutscheBank Trust Company Americas or another trustee to be named in a prospectus supplement. The unsecured subordinated debt securities will be issued under aseparate indenture to be entered into by us and Deutsche Bank Trust Company Americas or another trustee to be named in a prospectus supplement.

The unsecured senior debt indenture is filed as an exhibit to the registration statement of which this prospectus is a part. If we issue any senior subordinateddebt securities or subordinated debt securities, we will file forms of the senior subordinated debt indenture and the subordinated debt indenture, as applicable, byamendment to the registration statement of which this prospectus is a part. You should refer to the applicable indenture for more specific information.

The senior debt securities will rank equally with each other and with all of our other unsecured and unsubordinated indebtedness. Our senior debt securitieswill effectively be subordinated to our secured indebtedness, including amounts we have borrowed under any secured revolving or term credit

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NineMonthsEnded

September,2017

YearEndedDecember31,

2016 2015 2014 2013 2012 Ratio of earnings to fixed charges (1) 4.4x (2) (2) 7.4x 5.9x

(1) For the nine month period ended September 30, 2017, our earnings were inadequate to cover our fixed charges by $71.2 million.

(2) For the years ended December 31, 2015 and December 31, 2014, our earnings were inadequate to cover our fixed charges by$1,550.9 million and $2,625.5 million, respectively. Net loss from continuing operations before income taxes of $1,471.2 million and$2,548.8 million for the years ended December 31, 2015 and December 31, 2014 included a non-cash loss on impairment of$2,746.4 million and $4,218.7 million, respectively.

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facility and ship mortgages or bonds, and the liabilities of our subsidiaries. The senior subordinated debt securities will be subordinate and junior in right ofpayment, as more fully described in an indenture and in any applicable supplement to the indenture, to the senior indebtedness designated in such indenture orsupplemental indenture. The subordinated debt securities will be subordinate and junior in right of payment, as more fully described in an indenture and in anyapplicable supplement to the indenture, to all of our senior and senior subordinated indebtedness.

We will include the specific terms of each series of the debt securities being offered in a supplement to this prospectus.

DESCRIPTIONOFCLASSAORDINARYSHARES

For a full description of our Class A Ordinary Shares, nominal value $0.10 per share (the "Class A Ordinary Shares"), please see the documents identified inthe section "Where You Can Find More Information; Incorporation by Reference" in this prospectus.

DESCRIPTIONOFPREFERENCESHARESANDORDINARYSHARES

Our articles of association do not expressly contemplate the issuance of preference shares or a new class of ordinary shares. However, subject to sufficientauthorization being in place for the allotment and issuance of shares, preference shares or a new class of ordinary shares could be issued in the future with suchrights or restrictions either as are determined by resolution of the shareholders or as determined by our board. Pre-emption rights may apply to such issuance. Suchpre-emption rights would provide that when we wish to issue our "ordinary shares" ( i.e. shares other than shares which, with respect to dividends or capital, carrya right to participate only up to a specified amount of distribution) for cash, such shares must first be offered to the existing shareholders in proportion to theirrespective nominal amounts ( i.e. par values) of their holdings. If any preference shares or new class of ordinary shares issued by us carried a right to a fixedincome, pre-emption would not apply to the issue of such shares. English law permits our shareholders, by special resolution or a provision in our articles ofassociation, to exclude pre-emptive rights for a period of up to five years.

To grant our board with the authority to issue and allot preference shares or a new class of ordinary shares, an "ordinary resolution" must be passed by ourshareholders. Such ordinary resolution must be approved by holders of a simple majority of the aggregate voting power of our entire issued share capital that, beingentitled to vote, vote on the resolution at a general meeting of the company. To remove any applicable pre-emption rights and amend our articles of association, a"special resolution" must be passed by our shareholders. Such special resolution must be approved by the holders of at least 75% of our entire issued share capitalthat, being entitled to vote, vote on the resolution at a general meeting of the company.

We will include the specific terms of each series of the preference shares and ordinary shares being offered in a supplement to this prospectus.

DESCRIPTIONOFWARRANTS

We may issue warrants to purchase Class A Ordinary Shares, preference shares, ordinary shares and debt securities. Each warrant will entitle the holder topurchase for cash a number of Class A Ordinary Shares, preference shares or ordinary shares or the principal amount of debt securities at the exercise price as, ineach case, will be described in, or can be determined from, the applicable prospectus supplement relating to the offered warrants.

Warrants may be issued independently or together with any securities and may be attached to or separate from the securities. The warrants will be issuedunder warrant agreements to be entered into between us and a bank or trust company, as warrant agent. You should read the particular terms of the

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warrants, which will be described in more detail in the applicable prospectus supplement. The particular terms of any warrants offered by any prospectussupplement, and the extent to which the general provisions summarized below may apply to the offered securities, will be described in the prospectus supplement.

The applicable prospectus supplement will describe the terms of warrants we offer, the warrant agreement relating to the warrants and the certificatesrepresenting the warrants, including, to the extent applicable:

• the title of the warrants;

• the aggregate number of warrants;

• the price or prices at which the warrants will be issued;

• the currency or currencies, including composite currencies or currency units, in which the price of the warrants may be payable;

• the designation, number or aggregate principal amount and terms of the securities purchasable upon exercise of the warrants, and the proceduresand conditions relating to the exercise of the warrants;

• the date on which the right to exercise the warrants will commence, and the date on which the right will expire;

• the designation and terms of any related securities with which the warrants are issued, and the number of the warrants issued with each security;

• the date, if any, on and after which the warrants and the related securities will be separately transferable;

• the maximum or minimum number of warrants which may be exercised at any time;

• any other specific terms of the warrants; and

• if appropriate, a discussion of material United States federal income or U.K. tax considerations.

DESCRIPTIONOFSHAREPURCHASECONTRACTS

We may issue share purchase contracts representing contracts obligating holders, subject to the terms of such share purchase contracts, to purchase from us,and us to sell to the holders, a specified or varying number of our Class A Ordinary Shares, preference shares, or ordinary shares at a future date or dates.Alternatively, the share purchase contracts may, subject to the terms of such share purchase contracts, obligate us to purchase from holders, and obligate holders tosell to us, a specified or varying number of Class A Ordinary Shares, preference shares, or ordinary shares. The price per share of our Class A Ordinary Shares,preference shares or ordinary shares and number of shares of our Class A Ordinary Shares may be fixed at the time the share purchase contracts are entered into ormay be determined by reference to a specific formula set forth in the share purchase contracts.

The applicable prospectus supplement will describe the terms of any share purchase contract. The share purchase contracts will be issued pursuant todocuments to be issued by us. You should read the particular terms of the documents, which will be described in more detail in the applicable prospectussupplement.

DESCRIPTIONOFGUARANTEES

We may issue guarantees of debt securities and other securities. The applicable prospectus supplement will describe the terms of any guarantees. Theguarantees will be issued pursuant to

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documents to be issued by us. You should read the particular terms of the documents, which will be described in more detail in the applicable prospectussupplement.

DESCRIPTIONOFUNITS

We may issue units of securities consisting of one or more share purchase contracts, warrants, debt securities, guarantees, Class A Ordinary Shares, preferenceshares, ordinary shares or any combination thereof. The applicable prospectus supplement will describe the terms of any units and the securities comprising theunits, including whether and under what circumstances the securities comprising the units may or may not be traded separately. The units will be issued pursuant todocuments to be issued by us. You should read the particular terms of the documents, which will be described in more detail in the applicable prospectussupplement.

PLANOFDISTRIBUTION

We will set forth in the applicable prospectus supplement a description of the plan of distribution of the securities that may be offered pursuant to thisprospectus.

LEGALMATTERS

Latham & Watkins LLP will be requested to advise us with respect to the validity under English law, if applicable, of any securities that may be offeredpursuant to this prospectus. Latham & Watkins LLP may also be requested to advise us with respect to the validity under New York law, if applicable, of anysecurities that may be offered pursuant to this prospectus. Any underwriters will be advised about other issues relating to any offering by their own legal counsel.

EXPERTS

The consolidated financial statements of Ensco plc and its subsidiaries as of December 31, 2016 and 2015, and for each of the years in the three-year periodended December 31, 2016, and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2016 have beenincorporated by reference herein in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, andupon the authority of said firm as experts in accounting and auditing.

With respect to the unaudited interim financial information for the periods ended March 31, 2017, June 30, 2017, and September 30, 2017, incorporated byreference herein, the independent registered public accounting firm has reported that they applied limited procedures in accordance with professional standards fora review of such information. However, their separate reports included in the Company's quarterly reports on Form 10-Q for the quarter ended March 31, 2017,June 30, 2017, and September 30, 2017, and incorporated by reference herein, states that they did not audit and they do not express an opinion on that interimfinancial information. Accordingly, the degree of reliance on their report on such information should be restricted in light of the limited nature of the reviewprocedures applied. The accountants are not subject to the liability provisions of Section 11 of the Securities Act for their report on the unaudited interim financialinformation because that report is not a "report" or a "part" of the registration statement prepared or certified by the accountants within the meaning of Sections 7and 11 of the Securities Act.

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$500,000,000

Enscoplc%SeniorNotesdue2026

PROSPECTUSSUPPLEMENT

,2018

DeutscheBankSecuritiesCitigroupBNPPARIBAS

BofAMerrillLynchDNBMarkets

HSBCMorganStanley

SEB