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2019AnnualMeetingofStockholdersInvestorPresentation

AboutMcDermottPremier,fully-integratedprovideroftechnology,engineeringandconstructionsolutionstotheenergyindustryOperatinginover54countries,McDermott’slocallyfocusedandglobally-integratedresourcesincludeapproximately32,000employees,adiversifiedfleetofmarineconstructionvesselsandfabricationfacilitiesaroundtheworldOnMay10,2018,completedthecombinationwithChicagoBridge&IronCompanyN.V.(“CB&I”)throughaseriesoftransactions(the“Combination”)EngagedBoardCommittedtoSoundCorporateGovernanceandOversightofBusinessStrategyTheBoardisaninvaluablesourceofperspectiveandinsight,overseeingandengaginginourstrategyforcontinuedgrowthTheCombinationresultedintheadditionoffivenew,experiencedandqualifiedmemberstotheBoard,providingforimmediaterefreshmentandadiversemixofskills,experience,knowledgeandindependenceforeffectivedecision-makingandriskoversightinsupportingourlong-termstrategyFirmlycommittedtocontinuingourstockholderoutreachprogramandincorporatingfeedback,whichhasresultedinbestpracticecorporategovernanceandexecutivecompensationpoliciesandprogramsStrongCompensationPracticesTheCompensationCommitteeseekstoprovidereasonableandcompetitivecompensation,withtheelementsoftotaldirectcompensation,orTDC,targetedgenerallywithinapproximately15%ofmediancompensationofourmarketforcomparablepositionsSignificantcontinuedemphasisonvariable,“at-risk”compensationthatalignspaywithperformanceRigorousfinancialperformancemetricsutilizedincompensationprogramthataredirectlylinkedtoMcDermott’sstrategyExecutiveSummary

AboutMcDermottCompletedstrategiccombinationwithCB&IonMay10,2018Fundamentallydifferentandmuchlargercompanyascomparedto2017,withexpandedgeographic,operationalandtechnologicalreachFully,verticallyintegratedofferingforcustomersworldwide,withproductsolutionsspanningonshoreandoffshorefromconcepttocommissioningMcDermottisapremier,fullyintegratedproviderofengineering,constructionandtechnologysolutionstotheglobalenergyindustry$NewYorkStockExchangeMDR12MARINECONSTRUCTIONVESSELSCustomersNational,InternationalandIndependentEnergyCompanies54OperatingAreasCountriesinOilandGasProducingRegionsWorldwide7PROJECTSCOMPLETEDACROSSCONTINENTS300+PATENTSPATENTAPPLICATIONSANDTRADEMARKSINEASTLAND,TEXASFOUNDEDFABRICATIONFACILITIES

2019AnnualMeetingofStockholders–ItemsofBusinessElectionofDirectorsITEM1AdvisoryVotetoApproveNamedExecutiveOfficerCompensationITEM2RatificationofAppointmentofErnst&YoungLLPasAuditorsITEM3Approvalof2019McDermottInternational,Inc.Long-TermIncentivePlanITEM4TheBoardrecommendsavoteFOReachoftheseitemsofbusiness

2019AnnualMeetingofStockholders–ItemsofBusinessElectionofDirectorsITEM1TheBoardrecommendsavoteFOReachDirectornominee

WiththeclosingoftheCombination,ourBoardincreasedfrom9to11membersAdded5new,experiencedandqualifiedmemberstotheBoard,complementingtheBoard’sexistingskillsandexpertiseforpost-CombinationMcDermottEachdirectorbringsadiversemixofskills,experience,knowledgeandindependencetobestpositiontheBoardforeffectivedecision-makinginsupportingourlong-termstrategyGaryP.LuquetteChairoftheBoardFormerPresident,ChiefExecutiveOfficerFrank’sInternationalN.V.W.CraigKisselCompensationCommitteeChairFormerPresident,CommercialSystems,Trane,Inc.JohnF.Bookout,IIIPartner,ApolloGlobalManagement,LLCMaryL.Shafer-MalickiFormerSeniorVicePresidentandChiefExecutiveOfficer,BPAngola,BPp.l.c.PhilippeBarrilTransitionCommitteeChairChiefOperatingOfficer,SBMOffshore,N.V.DavidDicksonPresidentandChiefExecutiveOfficer,McDermottInternational,Inc.MarshaC.WilliamsFormerSeniorVicePresidentandChiefFinancialOfficer,OrbitzWorldwide,Inc.L.RichardFluryGovernanceCommitteeChairFormerChiefExecutiveOfficer,Gas,Power&Renewables,BPp.l.c.ForbesI.J.AlexanderExecutiveVicePresident,Jabil,Inc.JamesH.MillerFormerChairman,PPLCorporationNewlyRefreshedBoardisStronglyPositionedtoDriveSuccessWilliamH.Schumann,IIIAuditCommitteeChairFormerExecutiveVicePresidentFMCTechnologies,Inc.

FocusedandEngagedBoardOurBoardcontinuouslyevaluatesitscompositiontoensureeffectiveoversightofMcDermott’sstrategyindrivinglong-termstockholdervalueMandatoryretirementatage72CommitteeChairrotationafterfiveyearsofserviceAnnualreviewofcommitteecompositionandindividualdirectorskillsandqualificationsPeriodicthirdpartyevaluationofBoardandCommitteeeffectiveness,lastconductedearly201711ExecutiveLeadership11Energy/OilfieldServices9OtherPublicCompanyBoardExperience6ExperiencewithCoreCustomers10InternationalOperations7FinancialOversightResponsibilities10CorporateGovernanceIndependentPerspective10IndependentDirectors1Non-IndependentDirectorBalancedBoardTenure28ormoreyears11to4years35to7years5Lessthan1yearRelevantSkillsandExperienceCommitmenttoBoardRefreshment

TheBoardisactivelyinvolvedinstockholderoutreacheffortsIndependentBoardChairConsistentdirectorrefreshmentusingastandardizedprocessIndependentdirectorsearchfirmutilizedinselectingdirectorcandidatesMajorityvotingfordirectorsUseofindependentthirdpartyfacilitatorinconnectionwith2017annualBoardandCommitteeevaluationsManagementsuccessionplanningoversightBoardriskoversightLong-termincentivecompensationissubjecttoforfeitureAnnualincentivecompensationissubjecttolinearandcappedpayoutsUseofmultipleperformancemetricsSignificantstockownershipguidelinesfordirectorsandofficersDouble-triggerchange-in-controlagreementsAnnualreviewofshareutilizationIndependentcompensationconsultantAnnualreviewofpeergroupClawbackpolicyRepricingofunderwaterstockoptionsExcisetaxgross-upsDerivativestrading,hedgingorpledgingofMcDermottstockEmploymentcontractsprovidingforcontinuedemploymentStrongGovernanceandCompensationPracticesRemainaPriorityOurBoardbelievesinsoundcorporategovernanceandplacessignificantweightonstockholderfeedbackinmakingdecisionsoncorporategovernanceandexecutivecompensationpoliciesandprogramsCorporateGovernancePracticesCompensationPractices

CommitmenttoOngoingandMeaningfulStockholderEngagementOurBoardisfirmlycommittedtoconstructiveengagementwithourstockholdersandregularlyreviewsandrespondstotheirexpressedviewsIn2015,ourBoardestablishedaformalandextensivestockholderoutreachprogramonexecutivecompensationandgovernancematters,underwhichcertaindirectorsand/orexecutiveofficerssolicitfeedbackfromourstockholdersongovernanceandcompensationmattersDialoguewithstockholdershasledtoanumberofmeaningfulchangesMaintainingaSeparateChairoftheBoardandCEOMaintainingaBoardcomprisedofallindependentdirectors,exceptourCEOEngaginganindependentthird-partyfacilitatortoconducttheannualBoardandCommitteeevaluationseveryfewyearsorasneededAdoptionoflimitsonthenumberofoutsideboardsonwhichourdirectorsmayserveMaintainingacommitmenttoBoardrefreshmentGovernanceSocialandEnvironmentalCompensationIncreasingdisclosuresonourcorporatesocialresponsibilityandsustainabilityactivitiesEstablishingaformalCSRCorporateSteeringCommitteeandaGlobalCoordinationTeamtomorecloselyalignCSRactivitiestoourbusinessobjectivesTakingstepstoalignourCSRframeworktotheISO26000:10standard,whichprovidesguidancetoassessandaddresssocialresponsibilitiesthatarerelevantandsignificanttoMcDermott’s:missionandvision;operationsandprocesses;customers,employees,communitiesandotherstakeholders;andenvironmentalimpactEnhancingtransparencyinproxystatementdisclosuresregardingcompensationmatters,includingdisclosingspecifictargetsofourcompensationprogramsandhowtheytietoourstrategyIncludingarelativemetricforlong-termincentiveplanawardsRequiringdouble-triggervestingofequityawardsuponachangeincontrolIntroductionofacompetitorpeergroupforperformance-basedequityawardsAppropriaterevisionstoourcompensationpeergroups

2019AnnualMeetingofStockholders–ItemsofBusinessAdvisoryVotetoApproveNamedExecutiveOfficerCompensationITEM2TheBoardrecommendsavoteFORtheadvisoryvoteonNamedExecutiveOfficercompensation

OrderIntakeRevenuesBacklogPost-Combination:OurOperatingStrategyandIncreasedEarningsPotentialPost-Combination,McDermottisafundamentallydifferentandmuchlargercompanyascomparedtowherewewerein2017,withsignificantearningspotentialIntegrateCompletetheintegrationwithCB&Isuccessfullytoestablishatoptier,verticallyintegratedengineering,procurementandconstructioncompany,competitivelydifferentiatedintechnology,customerrelationships,DriveDrivesavingsthroughouttheorganizationandembodyabestinclassculture,withafocusonachievingsynergysavingsviatheCombinationProfitabilityInitiative,orCPIPositionDevelopstrategytopositionMcDermottforfuturegrowthbycapitalizingonarobustrevenueopportunitypipelineandgrowingendmarketsDisciplineExercisedisciplinedbiddingthroughthoroughevaluationandassessmentofprojectriskprofilesExecuteDeliverexcellenceinexecutionthroughimplementationoftheOneMcDermottWayOur2018operatingstrategyfollowingthecombinationwithCB&Iwastopioneeranewkindofcompany,withafocusonthefollowingstrategicobjectives:$inbillions

McDermott'scompensationprogramsaredesignedtoprovidecompensationthat:Attracts,motivatesandretainshigh-performingexecutivesProvidesperformance-basedincentivesthatrewardachievementofshort-termandlong-termbusinessgoalsandstrategicobjectiveswhilerecognizingindividualcontributionsAlignstheinterestsofourexecutiveswiththoseofourstockholdersStrategicObjectivePerformanceMetric2018ExecutiveIncentiveCompensationPlan(AnnualBonus)Integrate&ExecuteDriveprofitabilityviaimprovedprojectexecutionAdjustedOperatingIncomeDrivePrioritizeliquidityneedsAdjustedFreeCashFlow2018Long-TermIncentivePlanAwards—PerformanceUnitsPositionSupportfuturebusinessOrderIntakeIntegrate,Discipline&ExecuteGeneratereturnsforstockholdersRelativeTotalShareholderReturnCompensationPhilosophyLinksStrategyandOperationalPerformancePerformancemetricsandperformancelevelsusedwithinelementsofannualandlong-termcompensationsupportourstrategicandfinancialgoalsanddrivethecreationofstockholdervalue

TheCompensationCommitteeseekstoprovidereasonableandcompetitivecompensation,withtheelementsofTDCtargetedgenerallywithinapproximately15%ofmediancompensationofourmarketforcomparablepositions(marketrange)TheCompensationCommitteeconsideredthesignificantlyincreasedsizeandscaleofMcDermottpost-Combination,andidentifiedanewCompensationPeerGroupwithconsiderationofthefollowing:Post-CombinationbenchmarkingandcompensationreviewprocessledtochangesineachelementofCEO’s2018targetTDCPost-CombinationCompensationPeerGroupandCEOTargetTDCComparableexecutiveexpertiseComparablysizedexecutiverolesCompetitorsforexecutivetalentComparablerevenuesSimilarityofoperationsandbusinessmodelsOthercomparablefinancialandcapitalvaluemetricsIncreasedSize,ScopeandComplexityBenchmarkingofnewpeersNewmarketmediancompensationopportunitiesChangesinelementsofTDCNotwithstandingcompensationincreases,eachelementofCEO2018post-CombinationtargetTDCremainswithin3%ofmarketrangecompensation

90%AtRisk10%AnnualBaseSalaryFixedcashcompensationrecognizinganexecutiveofficer’sexperience,skillandperformance13%AnnualIncentive,orEICPVariablecompensationdesignedtorewardachievementofshort-termbusinessgoalsandstrategicobjectives,whilerecognizingindividualcontributions77%Long-TermIncentives,orLTIVariablecompensationdesignedtoaligninterestsofexecutiveswiththoseofourstockholderswithafocusonlong-termperformanceresultsMcDermott’scompensationprogramisdesignedtoaligninterestsofexecutiveswiththoseofourstockholderswithafocusonlong-termperformanceresultsCEO2018LTIValueReduction$8.3million$1.9million6/1/18PU*0246810$6.4million6/1/18RSU3/1/18RSULTIAwardValueonGrantDateLTIAwardValueasof12/31/18CEO2018Post-CombinationTargetTotalDirectCompensation*TheLTIawardvalueasofDecember31,2018isbasedonMcDermott’sclosingstockpriceasofDecember31,2018.ThevalueofperformanceunitsasofDecember31,2018isbasedonachievingthresholdperformance.SignificantMajorityofCEOPayisAtRisk…DemonstratingPayforPerformanceAlignment

2019AnnualMeetingofStockholders–ItemsofBusinessRatificationofAppointmentofErnst&YoungLLPasAuditorsITEM3TheBoardrecommendsavoteFORtheratificationoftheappointmentofErnst&YoungLLPasAuditors

AuditorandAuditCommitteeMattersEYwasappointedin2018followingacompetitiverequestforproposalprocess,replacingDeloitte&ToucheLLPasourprincipaloutsideauditorInselectingEYtoserveasMcDermott’sauditorovercompetingfirms,theAuditCommitteeconsidered,amongotherthings:IndeterminingwhethertoreappointEYforfiscalyear2019,theAuditCommitteeconsideredanumberoffactors,includingthequalityofEY’sauditandnon-auditwork,basedonitsoversightofthefirm’sworkproduct,EY’sreportsonitsqualitycontrolsanditsperformanceduring2018,externaldataonEY’sauditqualityandperformance,theappropriatenessofEY’sfeesandEY’swrittendisclosuresandindependenceletterTheAuditCommitteedeterminedthecontinuedengagementofErnst&YoungLLP(“EY”)forfiscalyear2019isinthebestinterestsofMcDermottandourstockholdersGlobal,nationalandlocalcapabilitiestohandlethebreadthandcomplexityofMcDermott’sglobaloperationsandabilitytorelyoncomponentregionalteamscorrespondingtotheprimarybusinesslocationsofMcDermottTechnicalexpertiseandknowledgeofMcDermott’sindustry,globaloperationsandpotentialrisksMcDermottwillfaceProposedleadpartnerandengagementteamexperience,qualificationsandeffectiveness;Relationships,resources,andprocessesusedtomonitoremerginglegislative,regulatory,andaccountingissuesProcessesforidentifyingandsharingwithMcDermottmanagementindustrybestpracticesandtrendsanddevelopmentsthataffectourbusinessenvironmentStyle,approachandfrequencyofcommunicationwiththeAuditCommitteeandmanagement;Approachtoidentifyingandresolvingtechnicalissueswithmanagement;Planforutilizinginternalauditactivitiestodriveefficiencyintheexecutionoftheexternalauditplan;Reasonablenessofestimatedfees,costsandbillingpracticesforauditandnon-auditservices;Processesformonitoringandmaintainingindependence;andProcessesforensuringconfidentialityofMcDermottintellectualcapitalfromanycompetitorsservedbythefirm.

2019AnnualMeetingofStockholders–ItemsofBusinessApprovalof2019McDermottInternational,Inc.Long-TermIncentivePlanITEM4TheBoardrecommendsavoteFORthe2019McDermottInternational,Inc.Long-TermIncentivePlan

Approvalof2019Long-TermIncentivePlanAlignswithStockholderInterests2019LTIPwillreplace2016LTIPandtheCB&ILTIPAdoptionof2019LTIPisnecessarytocontinueourequity-basedlong-termincentiveprogramandtoavoidhavingtopotentiallyincreasesignificantlythecashcomponentofourexecutivecompensationprograminordertoremaincompetitiveandadequatelycompensateouremployeesIndeterminingthenumberofsharestomakeavailableunderthe2019LTIP,theCompensationCommitteeconsidered:Numberof12,000,0002,475,000,plusunusedsharesreservedsharesreservedfrompriorplansAnnualLimitsonEmployeeGrantsMaximumannualperpersongrantof3,000,000sharessubjecttooptions.Maximumannualperpersongrantof3,000,000sharesintheformofrestrictedstockorrestrictedstockunits.Maximumannualcashpayoutof$12,000,000perpersonforperformanceunits.Noprovision.Asaresultoftheeliminationoftheperformance-basedcompensationexceptionunderSection162(m)oftheCode,theseperpersonlimitationsarenolongernecessary.Annuallimitsondirectorawardsremaininplace.MinimumVestingAwardstoemployeessubjecttoaminimumvestingperiodofoneyearfromthedateofgrant,subjecttoanexceptionforupto5%ofthesharesreserved.Allawards(includingdirectorawards)willhaveaminimumvestingperiodofoneyearfromthedateofgrant,subjecttoexceptionsforupto5%ofthesharesreservedaswellasfordirectorgrantsthatvestatthenextannualmeeting.OurBoardbelievesincentiveawardsarecriticaltoattracting,retainingandengaginghighlyqualifiedemployeesandtoaligningtheirfinancialinterestswiththefinancialinterestsofourstockholdersKeyChangesfrom2016LTIPKeyhistoricalstockusagedataunderthe2016LTIPAdviceofMeridianCompensationPartners,LLC,theindependentcompensationconsultantExpecteddilutionresultingfromthe2019LTIP2016LTIP2019LTIP