Marathon Oil : Financial, Operational and ESG Excellence Presentation

FINANCIAL, OPERATIONAL, &

ESG EXCELLENCE

December 2021

Forward-Looking Statements and Other Matters

This presentation (and oral statements made regarding the subjects of this presentation) contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These are statements, other than statements of historical fact, that give current expectations or forecasts of future events, including, without limitation: the Company's future capital budgets and allocations, future performance, expected free cash flow, emission targets and goals and estimated emission reductions, future debt levels, future debt reduction and the timing thereof, returns of capital to investors (including dividends and share repurchases, and the timing thereof), reinvestment rates, business strategy, drilling plans, capital efficiency, leasing and exploration activities, production, break-evens, free cash flow yields and other plans and objectives for future operations. Words such as "anticipate," "believe," "continue," "could," "estimate," "expect," "forecast," "future," "guidance," "intend," "may," "outlook," "plan," "positioned," "project," "seek," "should," "target," "will," "would,", or similar words may be used to identify forward-looking statements; however, the absence of these words does not mean that the statements are not forward-looking. This presentation includes certain forward‐looking, non‐GAAP financial measures, including, free cash flow or FCF, operating cash flow before working capital, reinvestment rate, capital expenditures, and net debt to EBITDAX. Free cash flow, which is free cash flow before dividend, is defined as net cash provided by operating activities adjusted for working capital, capital expenditures, and EG return of capital and other. Management believes this is useful to investors as a measure of the Company's ability to fund its capital expenditure programs, service debt, and other distributions to stockholders. The reinvestment rate is defined as total capital expenditures divided by operating cash flow before working capital. Management believes the reinvestment rate is useful to investors to demonstrate the Company's commitment to generating cash for use towards investor-friendly purposes (which includes balance sheet enhancement, base dividend and other return of capital). Cash flow from operations (CFO) is defined as net cash provided by operations adjusted for operating working capital. Management believes operating cash flow before working capital is useful to demonstrate the Company's ability to generate cash quarterly or year-to-date by eliminating differences caused by the timing of certain working capital items. Capital expenditures is defined as cash additions to property, plant and equipment adjusted for the change in working capital associated with property, plant and equipment, and additions to other assets. Management believes this is useful to investors as an indicator of Marathon's commitment to capital expenditure discipline by eliminating differences caused by the timing of certain working capital and other items. Net debt to EBITDAX is defined as long-term debt less cash and cash equivalents divided by Adjusted EBITDAX (net income excluding net interest expense, taxes, DD&A, and exploration, further adjusted for gains/losses on dispositions, impairments of proved property, goodwill, and equity method investments, unrealized derivative gain/loss on commodity instruments, effects of pension settlement losses and curtailments and other items that could be considered "non-operating" or "non-core" in nature). Management believes net debt to EBITDAX is useful to show the Company's ability to pay off long-term debt. Any such forward‐looking measures and estimates are intended to be illustrative only and are not intended to reflect the results that the Company will necessarily achieve for the period(s) presented; the Company's actual results may differ materially from such measures and estimates.

While the Company believes its assumptions concerning future events are reasonable, a number of factors could cause actual results to differ materially from those projected, including, but not limited to: conditions in the oil and gas industry, including supply/demand levels for crude oil and condensate, NGLs and natural gas and the resulting impact on price; changes in expected reserve or production levels; changes in political or economic conditions in the U.S. and Equatorial Guinea, including changes in foreign currency exchange rates, interest rates, inflation rates; actions taken by the members of the Organization of the Petroleum Exporting Countries (OPEC) and Russia affecting the production and pricing of crude oil; and other global and domestic political, economic or diplomatic developments; risks related to the Company's hedging activities; voluntary or involuntary curtailments, delays or cancellations of certain drilling activities; liability or corrective actions resulting from litigation or other proceedings and investigations; capital available for exploration and development; drilling and operating risks; lack of, or disruption in, access to storage capacity, pipelines or other transportation methods; well production timing; availability of drilling rigs, materials and labor, including the costs associated therewith; difficulty in obtaining necessary approvals and permits; non-performance by third parties of contractual or legal obligations, including due to bankruptcy; changes in our credit ratings; hazards such as weather conditions, a health pandemic (including COVID- 19), acts of war or terrorist acts and the government or military response thereto; shortages of key personnel, including employees, contractors and subcontractors; security threats, including cybersecurity threats and disruptions to our business and operations from breaches of our information technology systems, or breaches of the information technology systems, facilities and infrastructure of third parties with which we transact business; changes in safety, health, environmental, tax and other regulations, requirements or initiatives, including initiatives addressing the impact of global climate change, air emissions, or water management; other geological, operating and economic considerations; and the risk factors, forward-looking statements and challenges and uncertainties described in the Company's 2020 Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and other public filings and press releases, available at https://ir.marathonoil.com/. Except as required by law, the Company undertakes no obligation to revise or update any forward-looking statements as a result of new information, future events or otherwise.

This presentation includes non-GAAP financial measures. Reconciliations of the differences between non-GAAP financial measures used in this presentation and their most directly comparable GAAP financial measures are available at https://ir.marathonoil.com/in the 3Q21 Investor Packet.

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Financial, Operational, & ESG Excellence

"We know how important it is to deliver reliable and affordable energy to the world while also prioritizing environmental, social and governance excellence. Marathon Oil was among the first to move to an Exploration and Production business model that prioritizes corporate returns and

sustainable free cash flow as opposed to a simple production growth-focused strategy.

This underlying framework for success has delivered financial sustainability that is competitive not only with our direct E&P peers, but the broader market. As we move forward, we must continue to embed strong ESG practices to deliver non-financialoutcomes that similarly compete with the broader market and protect our license to operate as we transition to a lower carbon future."

Lee Tillman

Chairman, President & CEO

"At Marathon Oil, we understand that successful companies not only must be financially strong, but also

committed to environmental, social and governance excellence.

Our stakeholders have come to expect the company's measured, fact-based approach to drive results. And, early in 2021, Marathon Oil did just that by setting an aggressive goal to meaningfully reduce our GHG emissions intensity by 2025. This medium-term emissions reduction goal ensures clear accountability which we complemented with a short-termGHG emissions intensity reduction target that directly impacts executive compensation."

Lisa Hyland

Chair, HES&CR Committee

Marathon Oil Corporation Board of Directors

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Business and Strategy Overview	Safety and Environmental	Social	Governance

Financial, Operational, & ESG Excellence

Business and

Strategy Overview

Safety

Environmental

Social

Governance

• Independent E&P focused on highest quality U.S. resource plays with complementary E.G. integrated gas business
• Clear capital allocation framework and strategy that considers commodity cyclicality and long-term climate risks
• High quality portfolio resilient in a lower carbon future
• Investment grade balance sheet and commitment to meaningful return of capital to shareholders
• Committed to safe, healthy, and secure workplaces with track record of top quartile TRIR1 performance
• Safety performance (TRIR) for employees and contractors integrated into compensation scorecards
• Meeting global energy demand while delivering top quartile GHG intensity
• Driving significant improvement in GHG and methane intensity, consistent with Paris Agreement objectives
• Basin-specificwater management strategy preserves fresh water and reduces operational risks
• Investing to build healthier, safer, more resilient, and stronger local communities
• Promoting equality, diversity, and inclusion
• Independent and diverse Board of Directors with strong set of skills and experience
• Demonstrating executive compensation leadership: proactive compensation reductions with compensation frameworks enhanced and redesigned to further improve stakeholder alignment

See Appendix for definitions and footnotes

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Business and Strategy Overview	Safety and Environmental	Social	Governance

Marathon Oil Corporation (NYSE: MRO) Overview

Independent E&P focused on highest quality U.S. resource plays

Who We Are

• Independent exploration and production (E&P) company focused on highest quality U.S. resource plays with complementary integrated gas business in Equatorial Guinea

What We Do

• Competitive corporate returns and sustainable free cash flow through disciplined reinvestment rate framework
• Responsibly deliver leading cash returns to shareholders which are sustainable long-term and resilient through commodity price cycles

How We Do It

• Keeping our workforce safe, minimizing our environmental impact, partnering with and investing in local communities, best- in-classgovernance

Bakken

~255k net acres

Permian

~135k net acres

Equatorial Guinea

• Operated interest in Alba field PSC
• Equity interests in world-class integrated gas infrastructure uniquely positioned for continued gas aggregation

SCOOP / STACK

~250k net acres

Eagle Ford

~160k net acres

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