Occidental Petroleum · Earnings release · 8-K Exhibit 99

PRESS RELEASE

Occidental Announces 1st Quarter 2026 Results

•T1Advanced debt reduction priorities, repaying $7.1 billion of principal debt through May 5 and reducing principal debt to $13.3 billion, and progressing towards $10.0 billion milestone

•T2Strong operational performance from continuing operations drove $1.4 billion of operating cash flow and $3.2 billion of operating cash flow before working capital

•Capital expenditures of $1.6 billion, noncontrolling interest contributions of $50 million, and free cash flow before working capital from continuing operations of $1.7 billion

•T3Total company production of 1,426 Mboed exceeded the high end of guidance

•Midstream and marketing pre-tax adjusted income exceeded the high end of guidance

•Reported EPS of $3.13; adjusted EPS from continuing operations of $1.06

HOUSTON — May 5, 2026 — Occidental (NYSE: OXY) today announced results for the first quarter of 2026, including net income attributable to common stockholders of $3.2 billion, or earnings per diluted share (EPS) of $3.13, and adjusted income from continuing operations attributable to common stockholders of $1.1 billion, or adjusted EPS from continuing operations of $1.06. The difference between net income attributable to common stockholders and adjusted income attributable to common stockholders is mainly comprised of the gain on the sale of OxyChem within discontinued operations, partially offset by the impact of derivatives losses and early debt redemption premiums.

“Our first quarter results reflect our strong operational performance and the outstanding work of our teams executing across our portfolio. T4Even with the challenges in the Middle East, everyone - from our staff to our partners and host governments - has remained committed to safety, asset reliability and disciplined execution,” said President and Chief Executive Officer Vicki Hollub. “Over the past decade, T5we have made deliberate, strategic decisions that have transformed Occidental’s portfolio into the most resilient, competitive, and high-quality portfolio in our history. That foundation supported our first quarter performance. We further advanced our deleveraging program, reduced costs, improved efficiency, and delivered better outcomes with fewer resources. These results demonstrate Occidental’s ability to generate value, strengthen our balance sheet, and maintain leadership through market cycles.”

First quarter operating cash flow from continuing operations of $1.4 billion T6included a use of working capital of $1.8 billion, which was mainly driven by higher receivables resulting from the sharp increase in commodity prices in March, together with typical seasonal first quarter cash requirements for employee benefits, interest payments and property taxes.

QUARTERLY RESULTS

Oil and Gas

Pre-tax income from oil and gas for the first quarter of 2026 totaled $1.0 billion, compared to $0.7 billion for the fourth quarter of 2025. Excluding items affecting comparability, the increase was primarily driven by higher realized crude oil prices, partially offset by lower crude oil volumes. First quarter average WTI and Brent marker prices were $71.93 per barrel and $77.93 per barrel, respectively. T7Average worldwide realized crude oil prices increased by 18% from the previous quarter

to $69.91 per barrel, while average worldwide realized natural gas liquids prices increased by 14% to $18.99 per barrel. Average domestic realized gas prices fell by 10% to $1.01 per thousand cubic feet (Mcf).

Total global production for the first quarter of 2026 averaged 1,426 thousand barrels of oil equivalent per day (Mboed). This surpassed the high end of guidance led by contributions from the Permian, Rockies and Gulf of America business units.

Midstream and Marketing

Midstream and marketing reported a pre-tax loss of $87 million for the first quarter of 2026, compared to pre-tax income of $204 million in the previous quarter. Excluding items affecting comparability, the midstream and marketing results exceeded the high end of guidance. Quarter-over-quarter improvements were attributed to higher crude margins related to the timing impact of crude sales, higher gas margins from transportation capacity optimizations and higher sulfur prices at Al Hosn. WES equity method investment income for the first quarter was $138 million.

Supplemental Non-GAAP Measures

This press release refers to adjusted income - continuing operations, operating cash flow before working capital - continuing operations, capital expenditures, net of noncontrolling interest - continuing operations, free cash flow before working capital - continuing operations and adjusted selling, general and administrative (SG&A), other operating and non-operating expenses, which are supplemental measures not calculated in accordance with generally accepted accounting principles in the United States (GAAP). These non-GAAP financial measures have limitations as analytical tools and should not be considered in isolation or as an alternative to the comparable GAAP financial measures. Definitions of adjusted income - continuing operations and a reconciliation to net income (loss), along with operating cash flow before working capital - continuing operations, capital expenditures, net of noncontrolling interest - continuing operations, free cash flow before working capital - continuing operations and adjusted SG&A, other operating and non-operating expenses and a reconciliation to the comparable GAAP financial measures, are included in the financial schedules of this press release.

Occidental’s definition of adjusted income - continuing operations, operating cash flow before working capital - continuing operations, capital expenditures, net of noncontrolling interest - continuing operations, free cash flow before working capital - continuing operations and adjusted SG&A, other operating and non-operating expenses may differ from similarly titled measures provided by other companies in our industry and as a result may not be comparable.

About Occidental

Occidental is an international energy company that produces, markets and transports oil and natural gas to maximize value and provide resources fundamental to life. The company leverages its global leadership in carbon management to advance lower-carbon technologies and products. Headquartered in Houston, Occidental primarily operates in the United States, the Middle East and North Africa. To learn more, visit oxy.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to, statements about Occidental’s expectations, beliefs, plans or forecasts. All statements other than statements of historical fact are “forward-looking statements” for purposes of federal and state securities laws, including, but not limited to: any projections of earnings, revenue or other financial items or future financial position or sources of financing; any statements of the plans, strategies and objectives of management for future operations or business strategy; any statements regarding future economic conditions or performance; any statements of belief; and any statements of assumptions underlying any of the foregoing. Words such as “estimate,” “project,” “predict,” “will,”

“would,” “should,” “could,” “may,” “might,” “anticipate,” “plan,” “intend,” “believe,” “expect,” “aim,” “goal,” “target,” “objective,” “commit,” “advance,” “guidance,” “priority,” “focus,” “assumption,” “likely” or similar expressions that convey the prospective nature of events or outcomes are generally indicative of forward-looking statements. You should not place undue reliance on these forward-looking statements, which speak only as of the date of this press release unless an earlier date is specified. Unless legally required, Occidental does not undertake any obligation to update, modify or withdraw any forward-looking statement as a result of new information, future events or otherwise.

Forward-looking statements involve estimates, expectations, projections, goals, forecasts, assumptions, risks and uncertainties. Actual outcomes or results may differ from anticipated results, sometimes materially. Factors that could cause results to differ from those projected or assumed in any forward-looking statement include, but are not limited to: general economic conditions, including slowdowns and recessions, domestically or internationally; Occidental’s indebtedness and other payment obligations, including the need to generate sufficient cash flows to fund operations; Occidental’s ability to successfully monetize select assets and repay or refinance debt and the impact of changes in Occidental’s credit ratings or future increases in interest rates; assumptions about energy markets; global and local commodity and commodity-futures pricing fluctuations and volatility; supply and demand considerations for, and the prices of, Occidental’s products and services; actions by the Organization of the Petroleum Exporting Countries (OPEC) and non-OPEC oil producing countries; results from operations and competitive conditions; future impairments of Occidental’s proved and unproved oil and gas properties or equity investments, or write-downs of productive assets, causing charges to earnings; unexpected changes in costs; government actions (including the effects of announced or future tariff increases and other geopolitical, trade, tariff, fiscal and regulatory uncertainties), war (including the Russia-Ukraine war and conflicts in the Middle East) and political conditions and events (such as in Latin America); inflation, its impact on markets and economic activity and related monetary policy actions by governments in response to inflation; availability of capital resources, levels of capital expenditures and contractual obligations; the regulatory approval environment, including Occidental’s ability to timely obtain or maintain permits or other government approvals, including those necessary for drilling and/or development projects; Occidental’s ability to successfully complete, or any material delay of, field developments, expansion projects, capital expenditures, efficiency projects, acquisitions or divestitures; risks associated with acquisitions, mergers and joint ventures, such as difficulties integrating businesses, uncertainty associated with financial projections or projected synergies, restructuring, increased costs and adverse tax consequences; uncertainties and liabilities associated with acquired and divested properties and businesses, including retained liabilities and indemnification obligations associated with the chemical business; uncertainties about the estimated quantities of oil, NGL and natural gas reserves; lower-than-expected production from development projects or acquisitions; Occidental’s ability to realize the anticipated benefits from prior or future streamlining actions to reduce fixed costs, simplify or improve processes and improve Occidental’s competitiveness; exploration, drilling and other operational risks; disruptions to, capacity constraints in, or other limitations on the pipeline systems that deliver Occidental’s oil and natural gas and other processing and transportation considerations; volatility in the securities, capital or credit markets, including capital market disruptions and instability of financial institutions; health, safety and environmental (HSE) risks, costs and liability under existing or future federal, regional, state, provincial, tribal, local and international HSE laws, regulations and litigation (including related to climate change or remedial actions or assessments); legislative or regulatory changes, including changes relating to hydraulic fracturing or other oil and natural gas operations, retroactive royalty or production tax regimes, and deep-water and onshore drilling and permitting regulations; Occidental’s ability to recognize intended benefits from its business strategies and initiatives, such as the sale of OxyChem, Occidental’s low-carbon ventures businesses and announced greenhouse gas emissions reduction targets or net-zero goals; changes in government grant or loan programs; potential liability resulting from pending or future litigation, government investigations and other proceedings; disruption or interruption of production or facility damage due to accidents, chemical releases, labor unrest, weather, power outages, natural disasters, cyber-attacks, terrorist acts or insurgent activity; the scope and duration of global or regional health pandemics or epidemics and actions taken by government authorities and other third parties in connection therewith; the creditworthiness and performance of Occidental’s counterparties, including financial institutions, operating partners and other parties; failure of risk management; Occidental’s ability to retain and hire key personnel; supply, transportation and labor constraints; reorganization or restructuring of Occidental’s operations; changes in state, federal or international tax rates, deductions, incentives or credits; and actions by third parties that are beyond Occidental’s control.

Additional information concerning these and other factors that may cause Occidental’s results of operations and financial position to differ from expectations can be found in Occidental’s other filings with the U.S. Securities and Exchange Commission, including Occidental’s Annual Report on Form 10-K for the year ended December 31, 2025, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K.

Contacts

Media

Investors

Eric Moses

Babatunde A. Cole

eric_moses@oxy.com

investors@oxy.com

Occidental Petroleum Corporation

Earnings Release Schedules Index

Schedule # and Description

1.Summary Highlights

2.Items Affecting Comparability Detail

•Before Tax Allocations

•After Tax Allocations

3.Segment Results

a.Reported and Adjusted Segment Results

b.Reconciliation of EPS and Summary of Income Taxes for Adjusted Results

4.Consolidated Condensed Statements of Operations

5.Consolidated Condensed Balance Sheets

6.Consolidated Condensed Statements of Cash Flows

a.Consolidated Condensed Statements of Cash Flows

b.Detail of Free Cash Flow (non-GAAP), Capital Expenditures, Net of Noncontrolling Interest (non-GAAP) and Depreciation, Depletion and Amortization

7.Oil & Gas Net Production Volumes Per Day by Geographic Locations

•MBOE/D

•By Commodity

8.Oil & Gas Net Sales Volumes Per Day and Realized Prices by Geographic Locations

•MBOE/D

•Realized Prices and Related Index Prices

9.Oil and Gas Metrics

SCHEDULE 1

Occidental Petroleum Corporation

Summary Highlights

Quarterly

Qtr 1

Qtr 2

Qtr 3

Qtr 4

TY

Qtr 1

Qtr 2

Qtr 3

Qtr 4

YTD

Net Income ($ millions)

Reported income attributable to common stockholders

$

$

$

$

$

$

$

—

$

—

$

$

Reported EPS - Diluted ($/share)

$

$

$

$

$

$

$

—

$

—

$

—

$

Effective tax rate - Reported income - Continuing Operations (%)

%

%

%

%

(a)

%

%

—

%

—

%

—

%

%

Adjusted income attributable to common stockholders (Non-GAAP) (b)

$

$

$

$

$

$

$

—

$

—

$

$

Adjusted EPS - Diluted (Non-GAAP) ($/share) (c)

$

$

$

$

$

$

$

—

$

—

$

—

$

Effective tax rate - Adjusted income - Continuing Operations (%)

%

%

%

%

%

%

—

%

—

%

—

%

%

Average Shares Outstanding - Reported Income and Adjusted Income

Basic (millions)

—

Diluted (millions)

—

Daily Production Volumes

Total US (MBOE/D)

—

US Oil (MBBL/D)

—

Worldwide Production (MBOE/D)

—

Worldwide Sales (MBOE/D)

—

Commodity Price Realizations

Worldwide Oil ($/BBL)

$

$

$

$

$

$

$

—

$

$

$

Worldwide NGL ($/BBL)

$

$

$

$

$

$

$

—

$

$

$

Domestic Gas ($/MCF)

$

$

$

$

$

$

$

—

$

$

$

Free Cash Flow - Continuing Operations ($ millions) (Non-GAAP) (d)

Operating cash flow before working capital (Non-GAAP)

$

$

$

$

$

$

$

—

$

—

$

—

$

Less: Capital expenditures, net of noncontrolling interest (Non-GAAP)

$

$

$

$

$

$

—

—

—

Free Cash Flow Before Working Capital (Non-GAAP)

$

$

$

$

$

$

$

—

$

—

$

—

$

Year-to-date

Mar

Jun

Sep

Dec

Mar

Jun

Sep

Dec

Net Income ($ millions)

Reported income attributable to common stockholders

$

$

$

$

$

Reported EPS - Diluted ($/share)

$

$

$

$

$

Effective tax rate on reported income-Continuing Operations (%)

%

%

%

%

%

Effective tax rate on reported income-Continuing & Discontinued Operations (%)

%

%

%

%

%

Adjusted income attributable to common stockholders (Non-GAAP) (b)

$

$

$

$

$

Adjusted EPS - Diluted (Non-GAAP) ($/share) (c)

$

$

$

$

$

Effective tax rate on adjusted income-Continuing Operations (%)

%

%

%

%

%

Average Shares Outstanding - Reported Income

Basic (millions)

Diluted (millions)

Average Shares Outstanding - Adjusted Income

Basic (millions)

Diluted (millions)

Daily Production Volumes

Total US (MBOE/D)

US Oil (MBBL/D)

Worldwide Production (MBOE/D)

Worldwide Sales (MBOE/D)

Commodity Price Realizations

Worldwide Oil ($/BBL)

$

$

$

$

$

Worldwide NGL ($/BBL)

$

$

$

$

$

Domestic Gas ($/MCF)

$

$

$

$

$

Free Cash Flow - Continuing Operations ($ millions) (Non-GAAP) (d)

Operating cash flow before working capital (Non-GAAP)

$

$

$

$

$

$

$

$

Less: Capital expenditures, net of noncontrolling interest (Non-GAAP)

Free Cash Flow Before Working Capital (Non-GAAP)

$

$

$

$

$

$

$

$

(a) Percentage impacted by reported net loss.

(b) See schedule 3a for non-GAAP reconciliation.

(c) See schedule 3b for non-GAAP reconciliation.

(d) See schedule 6b for non-GAAP reconciliation.

SCHEDULE 2

Occidental Petroleum Corporation

Items Affecting Comparability Detail

(amounts in millions)

Before Tax Allocations

Qtr 1

Qtr 2

Qtr 3

Qtr 4

TY

Qtr 1

Qtr 2

Qtr 3

Qtr 4

YTD

Oil & Gas

Domestic

Crude oil derivative losses

$

—

$

—

$

—

$

—

$

—

$

$

Losses on sales of assets and other, net

—

—

Legal reserves and other

—

—

—

—

Asset impairments and other charges, net

—

—

—

(6)

(6)

—

—

Total Domestic

—

—

—

—

International

Gains on sale of assets and other, net

—

—

—

—

—

Total International

—

—

—

—

—

—

—

—

Total Oil and Gas

—

—

—

—

Midstream & Marketing

Derivative gains (losses), net (a)

(9)

Gains (losses) on sales of assets and other, net

—

—

—

Asset impairments and other charges (a)

—

—

Equity method investments fair value gains

—

—

—

—

—

Total Midstream & Marketing

—

—

—

Corporate

Early debt extinguishment (b)

—

—

—

Early retirement costs

—

—

—

Acquisition-related costs

(6)

(6)

(1)

—

—

—

Total Corporate

(6)

(6)

(1)

—

—

—

State tax rate revaluation

—

—

—

—

—

Income tax impact on items affecting comparability

5

Income (loss) from continuing operations

—

—

—

Discontinued operations, net of taxes

—

—

Total

$

$

$

$

$

$

$

—

$

—

$

—

$

After Tax Allocations

Qtr 1

Qtr 2

Qtr 3

Qtr 4

TY

Qtr 1

Qtr 2

Qtr 3

Qtr 4

YTD

Oil & Gas

Domestic

Crude oil derivative losses

$

—

$

—

$

—

$

—

$

—

$

$

Losses on sales of assets and other, net

—

—

Legal reserves and other

—

—

—

—

Asset impairments and other charges, net

—

—

—

(5)

(5)

—

—

Total Domestic

—

—

—

—

International

Gains on sale of assets and other, net

—

—

—

—

—

Total International

—

—

—

—

—

—

—

—

Total Oil and Gas

—

—

—

—

Midstream & Marketing

Derivative gains (losses), net (a)

(7)

Gains (losses) on sales of assets and other, net

—

—

—

Asset impairments and other charges (a)

—

—

Equity method investments fair value gains

—

—

—

—

—

Total Midstream & Marketing

—

—

—

Corporate

Early debt extinguishment (b)

—

—

—

Early retirement costs

—

—

—

Acquisition-related costs

(5)

(4)

(1)

—

—

—

Total Corporate

(5)

(4)

(1)

—

—

—

State tax rate revaluation

—

—

—

—

—

Income (loss) from continuing operations

—

—

—

Discontinued operations, net of taxes

—

—

Total

$

$

$

$

$

$

$

—

$

—

$

—

$

(a) 2025 Included gains on sales, charges and derivative gains (losses) from income from equity investments and other.

(b) Included debt issuance costs in interest and debt expense, net.

SCHEDULE 3a

Occidental Petroleum Corporation

Reported and Adjusted Segment Results

(amounts in millions, except per share and effective tax rate amounts)

Reported Income

Qtr 1

Qtr 2

Qtr 3

Qtr 4

TY

Qtr 1

Qtr 2

Qtr 3

Qtr 4

YTD

Domestic

$

$

$

$

$

$

$

International

Total Oil & Gas

—

—

—

Midstream & Marketing

Segment income

—

—

—

Corporate

Interest

Other

Income from continuing operations before taxes

—

—

—

Taxes

Federal and state

International

Income from continuing operations

—

—

—

Less: Net income attributable to noncontrolling interest

(9)

Less: Preferred stock dividends and redemption premiums

Net income from continuing operations attributable to common stockholders

—

—

—

Discontinued operations, net of taxes

Net income attributable to common stockholders

$

$

$

$

$

$

$

—

$

—

$

—

$

Reported diluted income per share

$

$

$

$

$

$

$

—

$

—

$

—

$

Effective Tax Rate - Continuing Operations

%

%

%

%

%

%

%

Items Affecting Comparability

Domestic

$

—

$

$

$

$

$

$

—

$

—

$

—

$

International

—

—

—

—

—

—

—

—

Total Oil & Gas

—

—

—

—

Midstream & Marketing

—

—

—

Segment income (loss)

8

—

—

—

Corporate

Interest

—

—

—

—

—

Other

(6)

(6)

(1)

—

Income (loss) from continuing operations before taxes

7

—

—

—

Taxes

Federal and state

5

—

—

—

International

—

—

—

—

—

—

—

—

—

—

Income (loss) from continuing operations

—

—

—

Less: Net income attributable to noncontrolling interest

—

—

—

—

—

—

—

—

—

—

Less: Preferred stock redemption premiums

—

—

—

—

—

—

—

—

—

—

Net Income (loss) from continuing operations attributable to common stockholders

—

—

—

Discontinued operations, net of taxes

—

—

—

—

—

Net income (loss) attributable to common stockholders

$

$

$

$

$

$

$

—

$

—

$

—

$

Adjusted Income (Non-GAAP) (a)

Domestic

$

$

$

$

$

$

$

—

$

—

$

—

$

International

—

—

—

Total Oil & Gas

—

—

—

Midstream & Marketing

—

—

—

Adjusted segment income

—

—

—

Corporate

Interest

—

—

—

Other

—

—

—

Adjusted income from continuing operations before taxes

—

—

—

Taxes

Federal and state

—

—

—

International

—

—

—

Adjusted income from continuing operations

—

—

—

Less: Net income attributable to noncontrolling interest

(9)

—

—

—

Less: Preferred stock dividends

—

—

—

Adjusted income from continuing operations attributable to common stockholders

—

—

—

Adjusted diluted earnings per share (Non-GAAP) - Continuing Operations

$

$

$

$

$

$

$

Effective Tax Rate - Continuing Operations

%

%

%

%

%

%

%

(a) Non-GAAP Measure. Adjusted income - continuing operations is a non-GAAP measures. Occidental defines adjusted income - continuing operations as net income excluding the effects of significant transactions and events that affect earnings but vary widely and unpredictably in nature, timing and amount. These events may recur, even across successive reporting periods. This non-GAAP measure is not meant to disassociate those items from management’s performance, but rather is meant to provide useful information to investors interested in comparing Occidental’s earnings performance between periods. Reported net income is considered representative of management’s performance over the long term, and adjusted income - continuing operations is not considered to be an alternative to net income reported in accordance with GAAP.

SCHEDULE 3b

Occidental Petroleum Corporation

Reconciliation of EPS and Summary of Income Taxes for Adjusted Results

(amounts in millions, except per share and effective tax rate amounts)

RECONCILIATION OF EARNINGS PER SHARE

Qtr 1

Qtr 2

Qtr 3

Qtr 4

TY

Qtr 1

Qtr 2

Qtr 3

Qtr 4

YTD

Reported Diluted Earnings Per Share (GAAP)

$

$

$

$

$

$

$

After-Tax Adjustments for Items Affecting Comparability

Oil & Gas

Domestic

$

—

$

$

$

$

$

$

International

—

—

—

—

—

Midstream & Marketing

Corporate

Interest

—

—

—

Other

—

—

Taxes

—

—

—

Adjustment to diluted average shares for adjusted income & Warrant Inducements

—

—

—

—

Discontinued operations, net of taxes

—

—

Total After-Tax Adjustments for Items Affecting Comparability

$

$

$

$

$

$

$

—

$

—

$

—

$

Adjusted diluted earnings per share (Non-GAAP) - Continuing Operations

$

$

$

$

$

$

$

Average Diluted Shares Outstanding - Reported (millions)

Average Diluted Shares Outstanding - Adjusted (millions) (Non-GAAP)

ADJUSTED INCOME TAX BENEFIT (EXPENSE) - CONTINUING OPERATIONS

Qtr 1

Qtr 2

Qtr 3

Qtr 4

TY

Qtr 1

Qtr 2

Qtr 3

Qtr 4

YTD

Current

$

$

$

$

$

$

$

Deferred

TOTAL ADJUSTED INCOME TAX BENEFIT (EXPENSE) - CONTINUING OPERATIONS

$

$

$

$

$

$

$

—

$

—

$

—

$

Non-GAAP Measure. Adjusted income - continuing operations is a non-GAAP measures. Occidental defines adjusted income - continuing operations as net income excluding the effects of significant transactions and events that affect earnings but vary widely and unpredictably in nature, timing and amount. These events may recur, even across successive reporting periods. This non-GAAP measure is not meant to disassociate those items from management’s performance, but rather is meant to provide useful information to investors interested in comparing Occidental’s earnings performance between periods. Reported net income is considered representative of management’s performance over the long term, and adjusted income - continuing operations is not considered to be an alternative to net income reported in accordance with GAAP.

SCHEDULE 4

Occidental Petroleum Corporation

Consolidated Condensed Statements of Operations

(amounts in millions, except per-share amounts)

Qtr 1

Qtr 2

Qtr 3

Qtr 4

TY

Qtr 1

Qtr 2

Qtr 3

Qtr 4

YTD

REVENUES AND OTHER INCOME

Net sales

Oil & Gas

$

$

$

$

$

$

$

Midstream & Marketing

Eliminations

Total

—

—

—

Interest, dividends and other income

Gains (losses) on sale of assets and other, net

(5)

Total

—

—

—

COSTS AND OTHER DEDUCTIONS

Oil and gas lease operating expense