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UBS Resources and Energy Conference

June 2010

O I L S E A R C H L I M I T E D

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Oil Search Strategic Priorities

Assist ExxonMobil in delivering PNG LNG Project on time and on budget:

Transformational impact on Oil Search and PNG

ExxonMobil quality operator

Lays foundation for major LNG industry in PNG

Focus on further LNG development:Gas exploration and appraisal activities in PNG

Strategic PNG gas acquisitions

Partner alignment

Optimise oil field management

Undertake measured oil exploration

ACHIEVEMENT OF ABOVE WILL ENSURE CONTINUED LONG TERM TOP QUARTILE TSR PERFORMANCE

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PNG LNG ProjectUpdate

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PNG LNG Fields

PDL7

PDL1

PDL2

PDL6 PDL5

PDL9

PDL8

PDL8

PDL7 Nogoli Hides Camp

Ridge Camp

ProposedJuha Facility

ProposedHides

ConditioningPlant

CPF

APF

Power Plant

KUTUBU

ANGORE

AGOGO

HIDESJUHA

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PNG LNG Project Overview

6.6MTPA, 2 train development, operated by ExxonMobilFully contracted with continuing strong market interestBased on 9.3TCF proven and probable reserves commitmentFiscal stability agreement in place for 10.5TCF of production

APT at 17.5% ROR and 20% ROR. Max case tax rate of 41.7%Initial equities

ExxonMobil 33.2%Oil Search 29.0%Kroton2 (IPBC and Petromin) 16.8%MRDC (PNG Landowners) 2.8%Santos 13.5%Nippon Oil 4.7%

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PNG LNG Project Construction Activities Planned/Underway

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EPC Contractors

LNG Plant: Chiyoda/JGCOffshore Pipeline SaipemHides Gas Plant CBI/Clough JVOnshore Pipeline SpiecapagInfrastructure McConnellDowell/CCCEarly Works Clough/Curtain JVAssociated Gas (OSH) Aker Solutions

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Proposed LNG Plant Layout

FutureExpansion

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Proposed Hides Gas Conditioning Plant and Well Pads

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2010 PNG LNG Project Activities

Continued early works: Roads, bridges, camps, site preparation and training facilities

Order remaining long lead items and place purchase ordersOpen supply routesMobilisation of people and equipment by key contractorsAssociated Gas (AG) construction in oil fields

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Construction Activities

Oiyarip Camp Construction, Mendi

Bridge works, Highlands Highway

300-man Flotel at Kopi

POM Tech construction siteLNG plant site bypass road

Kobalu camp foundations

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PNG LNG Development Phases

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GasGrowth

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PNG Gas Growth

Key strategic priority for Oil Search is to grow gas business in PNGLNG remains optimum commercialisation route for additional gas Significant pre-investment - PNG LNG will provide infrastructure and capacity to facilitate expansion and provide excellent cost structure:

Use of capacity in pipeline, jetty, tanks and services

Trained local work force

Government is very supportive of, and expects, future gas growth

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PNG LNG Optimisation

Facilities optimisationReviewing available reservesAccelerating appraisal/exploration activities

Hides, Angore, Huria seismic - in preparation for drilling

Actively reviewing :Reserve addsConstruction cost synergies

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Two-Pronged Gas Growth Strategy

PNG LNG dedicated fields:

Proven (1P) 301 mmboe (OSH share) – all sold

Proven & probable (2P) 505 mmboe (OSH share)

Focus on moving 2P (& 3P) into 1P contractible category through field development optimisation and further appraisal

Other fields and exploration:

Existing proven & probable resources (2C) of 281 mmboe (OSH share), still to be commercialised

Programme to appraise discoveries and explore for new gas

Objective is to prove up sufficient proven contractible reserves to underwrite Trains 3 and 4

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Papuan Basin Geological Provinces & Play types

Aure FoldBeltProven Gas – Elk/Antelope

Primary play types:Tertiary limestone

Gulf of PapuaProven Gas – Pandora

Primary play types: Tertiary limestone reefs and Pliocene

turbidites

Foreland BasinProven Gas – Kimu, Douglas, Stanley,

ElevalaPrimary play types: Cretaceous sands

(Base regional seal) in tilted fault blocks and basement drapes

Frontal FoldBeltOil and Gas Production –

Kutubu + HidesPrimary play type: Early Cretaceous sands (Base regional seal) in hanging wall thrust

anticlines

Papuan Basin is lightly explored143 exploration wells in 215,000km2 of prospective area (an average of 1.5 wells/10,000km2)

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Existing Discoveries

PRL01

PPL234

PRL08PPL240

PRL03

PRL11

PDL7

PPL239

PDL1

PPL190

PPL219

PRL10

PRL02

PDL2

PDL4

PDL3

PRL09

PPL244

9°S

6°S

145°E50km

Kumul Terminal

PDL6PDL5

APRL14

PPL260

APPL249

APPL250

PPL

233

PDL9PDL8

142°E

Distribution of discovered 2P Reserve/Resource

Significant discovered oil & gas reserves/resources in Papuan Basin(predominantly in FoldBelt)Basin is predominantly gas prone85% of basin’s resources by boe are gas

Hides/Juha/Angore

Kutubu/Agogo/SEM

P’nyang

Pandora A

Uramu

Barikewa

Gobe/SEGElk/Antelope

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Port Moresby80km

Juha

Gobe

Kutubu & Agogo

Hides & Angore

144°E

8°S

6°S

146°E142°E

PNG Exploration Activity –2010-12

PPL219 OSHMananda Attic

PRL1 TLM 3D seismic processing

PRL9Barikewa 3

PRL11/PDL8 Exxon85 km 2D (Huria)

PPL234/244 OSH4720km2 3D

PPL267 NGEPanakawa

PPL259 EWDUbuntu

PPL268 InteroilMitsui agreement on condensate

stripping plant.Elk & Antelope appraisals

75km 2D seismic over leads.

PRL4 HZNStanley Appraisal

PPL285 SASOLAwapa

PPL234 OSHFlinders

TLM Douglas & Puk Puk Appraisal

1500km 2D

PRL5 HZNElevala Appraisal

PRL3 ExxonP’nyang Seismic

PDL2 OSH60km 2D

Drilling

Seismic

Legend

Over the next 2 years;20+ wells4,700+ km2 3D2,000+ km 2D

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4,700km2 of 3D seismic commenced April 2010 – biggest 3D survey ever undertaken in PNGAgreement signed with Talisman, to swap Talisman’s 35% equity in PPL 244 for 60% of OSH’s 80% equity in PPL 239. Takes OSH interest in PPL 244 to 80%. Oil Search to take over operatorship of PPL 244

Unlocking the Offshore

4700 km2 3D

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Coal Bed Methane Potential in PNG?

Oil Search awarded seven licences for CBM exploration, each approx 2,500 sq km in area

Three wells to be drilled in 2010 to further refine coal location, rank and thickness

If encouraging, drilling programme may continue

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PNG Attracting Growing Interest

Port Moresby144°E

8°S

6°S

146°E142°E

Talisman Equity Participation

80km

Juha

Gobe

Kutubu & Agogo

Hides & Angore

Port Moresby144°E

6°S

146°E142°E

Sasol & Interoil Equity Participation

80km

8°S

Juha

Gobe

Kutubu & Agogo

Hides & Angore

Port Moresby144°E

8°S

146°E142°E

Petroleum Licences

CSG Licences

6°S

80km

Oil Search Equity Participation

Juha

Gobe

Kutubu & Agogo

Hides & Angore

PNG transaction value ~US$1.4 billion over past 18 months, inc NOEX acquisition of AGL licencesTalisman and Sasol have acquired significant acreage in Western Forelands. Interoil has strong position in Eastern ForelandsOSH strategy focused on enhancing position in core PNG LNG Foldbeltacreage and Gulf - viewed as offering greatest potential for large gas discoveries

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MENA 2010 Exploration Summary

Commitment

Discretionary

Future Commitment

Well Types

Prospect/Lead (POS%)Mean Oil Gross (mmstb)Mean Gas Gross (bscf)

Seismic

CommitmentDiscretionary

Permit 2D(distance)/3D(area)

Sana’a Office

Dubai Office

Tajerouine

Le Kef

K42

Shakal

Block 7

Block 3

Taj. + Le Kef 600km

K42 200km

Shakal 50km

Jebel Milh (17%)28 mmstb

Block 3 & 7 400km

Al Meashar - oil discovery

Block 3/7 well,late 2010

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Production Outlook (net to OSH)

PNG LNG adds ~18 mmboe pa to OSH at plateau in 2015 onwards. 30 year Project lifeT3 could add an additional ~9 mmboe pa, with T4 of similar magnitude

Net

Pro

du

ctio

n (

bo

ep

d)

0

10,000

20,000

30,000

40,000

50,000

60,000

2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025

LNG GasLNG Gas

PNG DevelopmentPNG Development

70,000

80,000

Potential T3 LNG GasPotential T3 LNG Gas

LNG CondensateLNG Condensate

90,000

Potential T3 LNG CondensatePotential T3 LNG Condensate

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Oil SearchUndergoing Metamorphosis

Company undergoing major transformation through development of PNG LNG

Significant growth delivery over next 5 yearsPNG LNG T1 and T2Commitment to T3Reserves growth for further gas optimisation

Major strategic review underway to optimise growth path and prepare for major production and revenue growthDedicated review team in place,Focus areas :

PNG oil and gas operations interfacePNG LNG deliveryGas New Business (T3 & TA) plus other optionsGrowth and business developmentPNG stakeholder managementCapital managementOrganisation capability

Provide potential value, programmes and organisation to deliver through 1st LNG production

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O I L S E A R C H L I M I T E D