OGX reported results for 2Q11 and provided an update on its progress and plans. Key points include: 1) First oil production is expected in October/November 2011 from the Waimea field in the Campos Basin through an Extended Well Test. 2) New discoveries were announced in the Campos, Parnaíba and Santos Basins and the appraisal campaign continued across basins. 3) The company successfully raised $2.6 billion in bonds to fund operations until production makes it cash flow positive.

1. OGX: 2Q11 Results

2. DisclaimerThis presentation uses the terms “prospective resources” and “contingent resources” to describe those quantities of petroleum that are potentially recoverable from accumulations yet to be discovered. Because of the uncertainty to commerciality and lack of sufficient exploration drilling, prospective resources cannot be classified as reserves. Investors are advised that the U.S. Securities and Exchange Commission (SEC) and other international securities regulators do not recognize prospective and contingent resources. Prospective resources have a great amount of uncertainty as to their existence. There is no certainty that any portion of the prospective resources will be discovered and, if discovered, whether they could be developed economically. Therefore, investors are cautioned not to assume that all or any part of OGX’s prospective resources exist, or that they can be developed economically. Accordingly, information concerning prospective and contingent resources contained in this presentation are not comparable to information permitted to be made public by U.S. or other international companies subject to SEC reporting and disclosure requirements, especially Industry Guide 2 under the Securities Act.Certain of the information and conclusions set forth herein are based on projections. These projections were prepared for the limited purpose of analyzing the potential risks and benefits of an investment in the securities by illustrating under certain limited assumptions. In addition, because of the subjective judgments and inherent uncertainties of projections and because the projections are based on a number of assumptions, which are subject to significant uncertainties and contingencies that are beyond the control of OGX, there can be no assurance that the projections or conclusions derived therefrom will be realized. Under no circumstances should the projections set forth herein be regarded as a representation, warranty or prediction that OGX will achieve or is likely to achieve any particular future result. There can be no assurance that OGX’s future results or projections will not vary significantly from those set forth herein. Accordingly, investors may lose all of their investment to the extent the projections or conclusions included herein are not ultimately realized.This presentation also contains forward-looking statements, which may be identified by such words as "may", "plans", "expects", "believes" and similar expressions, or by their context. These statements are made on the basis of current knowledge and, by their nature, involve numerous assumptions and uncertainties. Various factors could cause OGX's actual future results, performance or events to differ materially from those described in this presentation. In no event shall the Company or the members of its board, directors, assigns or employees be liable to any third party (including investors) for investment decisions or acts or business carried out based on the information and statements that appear in this presentation, or for indirect damage, lost profit or related issues. The Company does not intend to provide to potential shareholders with a revision of the statements or an analysis of the differences between the statements and the actual results. You are urged to carefully review OGX's offering circular, including the risk factors included therein. This presentation does not purport to be all-inclusive or to contain all the information that a prospective investor may desire in evaluating OGX. Each investor must conduct and rely on its own evaluation, including of the associated risks, in making an investment decision.2

3. 2Q11 Highlights and Subsequent EventsFirst oil expected in October/November 2011Horizontal well OGX-26HP (Waimea) prepared for start-up of productionAll key equipment already secured and deliveredFPSO OSX-1 expected to arrive in SeptemberImportant new discoveries announced during the quarterCampos Basin: OGX-33 (Chimborazo) and OGX-52 (Tambora)Parnaíba Basin: OGX-34 (Bom Jesus)Santos Basin: OGX-30 (Salvador) and OGX-47 (Maceió)Continued intensification of appraisal campaign11 wells in Campos Basin, 2 wells in Parnaíba BasinNew drill-stem tests in horizontal wellsOGX-39HP (Pipeline) and OGX-44HP (Waikiki) in the Campos BasinNew tests to be performed in Campos and Santos BasinsDeclaration of commerciality in the Parnaíba Basin2 fields: Gavião Real and GaviãoAzulSuccessful $2.6bn bond offering3

4. Financial ResultsHighlights

5. 2Q11 Financial ResultsNet Financial Results: Impact of interest income, net losses on hedging of future commitments in foreign currency and negative impact of marking-to-market the fair value of financial instruments

6. Exploration Expenses: Primarily related to the acquisition of seismic data in the Parnaíba, Espírito Santo and Campos basins

7. General and Administrative Expenses: Increase in the number of employees from 184 to 266 between 2Q10 and 2Q11 and the stock options plan

8. Intangibles: Impacted by the intensification of our drilling campaign mainly in Campos, Santos and Parnaíba Basins5

9. FinancingSecuredUntil OGX is CashFlow PositiveTransaction HighlightsSummary of TermsOGX raised US$ 2.563 billion in a bond issuance on May 26, 2011

10. Moody’s, Fitch and S&P gave OGX B1, B+ and B (positive outlook) ratings, respectively

11. Largest non-investment grade offering ever in the industryInvestor BreakdownLAtam3%Asia3%Europe18%US78%6

12. Robust Cash Position Following Bond OfferingCash Position EvolutionCash AllocationAllocation by InstitutionR$ billionUS$ billionSolid cash position of R$7.0 billion, or US$4.5 billion, to support the exploratory commitments, the development and beginning of production until becomes cash flow positive

13. Foreign exchange hedge position of approximately US$ 901.2 million, representing approximately 5 months of financial commitments denominated in US$

14. Cash allocated in R$: Average cumulative gross return equivalent to approximately 103.6% of the Interbank Deposit Rate (CDI), or 11.7% p.a., generating R$223.4 million of interest income for the period

15. Cash Allocated in US$: Average cumulative gross return equivalent to approximately 1.5% p.a, generating US$ 2.8 million of interest income for the period.

16. Cash invested in fixed income instruments with some of the most solid financial institutions in Brazil7

17. Path to Production

18. Production Will Begin in the Waimea Accumulation Beginning of Production 1st Oil Production ConceptHorizontal production well already drilled, completed and successfully testedWet christmas tree installedWetchristmastreeOSX-1Electrical submersible pump installedBuoyRisersandUmbilicalsFlexiblelinesHydraulic Power Unit (HPU) installedMooringsand PilesUmbilicals deliveredMaincharacteristics:Productionpotentialof 40 kbpd w/ capacitylimited to 20 kbpd

19. Oilqualityof 20° API

20. Waterdepthof 140 metersFlexible lines deliveredAnchor system (moorings and piles) deliveredInstallation support vessel deliveredEWT approved by ANP (National Petroleum Agency)ElectricalsubmersiblepumpHorizontal WellOGX first oil expected for October/November through Extended Well Test (EWT)Illustrative frames9