3Q 2021 Earnings Presentation

THIRD QUARTER 2021

November 3, 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 retirement and the timing thereof, annualized cash interest expense savings, returns to investors (including dividends and share repurchases, and the timing thereof), balance sheet enhancement, reinvestment rates, business strategy, capital expenditure guidance, production guidance and trends, tax rates and equity method investments, E.G. equity method income guidance, capital efficiency, inventory levels, cost reductions, leasing and exploration activities, production, break-evens, free cash flow yields, inventory 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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Delivering Outsized Free Cash Flow and Meaningful Return of Capital

Increased base dividend, executed $200MM of share repurchases, raised buyback authorization to $2.5B

"Third quarter was once again characterized by both strong safety performance and an improving GHG emissions

trend. Additionally, through our commitment to capital discipline and our differentiated execution, we are delivering outsized financial outcomes, highlighted by over $1.3 billion of year-to-date free cash flow generation.

This strong financial performance in combination with the substantial improvement to our balance sheet has enabled us to dramatically accelerate the return of capital to equity holders.

Consistent with our framework, the shareholder will get the first call on cash flow.

We've raised our base dividend for the third consecutive quarter, we've repurchased $200 million of stock since October 1st, and we are targeting approximately $300 million of additional repurchases before year-end. Through our increased base dividend and share repurchases, we expect to return around 50% of our fourth quarter cash flow from operations to our equity holders.

Looking ahead to 2022, with our commitment to capital discipline firmly in place, no material debt maturities, and our upsized share repurchase authorization, we are well positioned to continue delivering outsized free cash flow generation and return of capital to our shareholders."

Lee Tillman

Chairman, President, and CEO

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What's New?

Key takeaways from 3Q21 earnings release

FINANCIAL

• Now expecting >$2B of 2021 FCF (strip)
• Meaningful sequential increase in FCF expected 4Q21 (higher prices, higher oil volumes, lower capex)

RETURN OF CAPITAL

• Raised base dividend by 20%; targeting ~$500MM of share repurchases 4Q21 ($200MM already executed)
• Expect to return ~50% of CFO to shareholders 4Q21
• Increased share repurchase authorization to $2.5B

OPERATIONAL

• No change to full year capex or total Company production guidance
• Initial productivity from Texas Delaware Oil Play multi- well pad exceeding expectations

2022 OUTLOOK

• Core priorities to remain unchanged
• Successfully positioned for continued top tier FCF generation and leading return of capital profile

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Framework for Success

Committed

to our

Framework

Powered

by our

Foundation

Corporate Returns

Free Cash Flow

Return of Capital

Differentiated Execution

Multi-Basin Portfolio

Balance Sheet Strength

ESG Excellence

Disciplined reinvestment in strongest rate-of-return opportunities

Sustainable free cash flow across wide range of commodity prices

Return meaningful capital to investors

Continuously improve performance, reduce costs, and deliver on commitments

Capital allocation flexibility, broad market access, supplier diversification, rapid sharing of best practices, platform for talent development

Continue improving investment grade balance sheet; maintain financial strength and flexibility to execute business plan

Safe operations, strong environmental performance,

trusted partner to local communities, and best-in-class governance

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