Diversified Energy Co

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

(Mark One)

þ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2026

or

¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number:001-41870

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the

preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90

days. Yes þ No ¨

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T

(§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes þ No ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging

growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of

the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised

financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes¨ Noþ

The registrant had 70,719,000 shares of common stock outstanding (excluding shares held by the Employee Benefit Trust) as of November 4, 2026.

Table of Contents

Glossary of Terms

ABS -Asset-Backed Security

ASU - Accounting Standards Update

Bbl -Barrel or barrels of oil or natural gas liquids

Btu -A British thermal unit, which is a measure of the amount of energy required to raise the temperature of one pound of water one

degree Fahrenheit

E&P -Exploration and production

EBITDAX -Earnings before interest, tax, depreciation, amortization and exploration expense

EPS -Earnings per share

GAAP - U.S. Generally Accepted Accounting Principles

Henry Hub -A natural gas pipeline delivery point that serves as the benchmark natural gas price underlying NYMEX natural gas

futures contracts

LNG - Liquefied natural gas

MBbls -Thousand barrels

Mcf -Thousand cubic feet of natural gas

Mcfe -Thousand cubic feet of natural gas equivalent

Midstream -Midstream activities include the processing, storing, transporting and marketing of natural gas, NGLs and oil

MMbtu -Million British thermal units

MMcf -Million cubic feet of natural gas

MMcfe -Million cubic feet of natural gas equivalent

MMcfepd -Million cubic feet of natural gas equivalent per day

Mont Belvieu -A mature trading hub with a high level of liquidity and transparency that sets spot and futures prices for NGLs

NGLs -Natural gas liquids, such as ethane, propane, butane and natural gasoline that are extracted from natural gas production

streams

NYMEX -New York Mercantile Exchange

NYSE - New York Stock Exchange

Oil -Includes crude oil and condensate

OPIS - Oil Price Information Service

PSU -Performance-based restricted stock unit

Realized price -The cash market price, less all expected quality, transportation and demand adjustments

RSU -Time-based restricted stock unit

SOFR -Secured Overnight Financing Rate

Upstream - Upstream activities include exploration, discovery, and extraction of natural gas, NGLs, and oil. Often referred to as

exploration and production activities, or E&P

WTI -West Texas Intermediate grade crude oil, used as a pricing benchmark for sales contracts and NYMEX oil futures contracts

Cautionary Statement Regarding Forward-Looking Statements

This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of the U.S. Private Securities Litigation

Reform Act of 1995 that can be identified by the following terminology, including the terms “may,” “might,” “will,” “could,”

“would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “seek,” “believe,” “estimate,” “predict,” “potential,” “continue,”

“contemplate,” “possible,” or the negative of these terms or other variations or comparable terminology, or by discussions of strategy,

plans, objectives, goals, future events or intentions. These forward-looking statements include all matters that are not historical facts.

They appear in a number of places throughout this Quarterly Report on Form 10-Q and include, but are not limited to, statements

regarding our intentions, beliefs or current expectations concerning, among other things, our results of operations, financial positions,

liquidity, prospects, growth strategies, future acquisitions or dispositions, and the natural gas and oil industry. By their nature,

forward-looking statements involve risk and uncertainty because they relate to future events and circumstances.

Forward-looking statements are not guarantees of future performance and the actual results of our operations, financial position and

liquidity, and the development of the markets and the industry in which we operate, may differ materially from those described in, or

suggested by, the forward-looking statements contained in this Quarterly Report on Form 10-Q. In addition, even if the results of

operations, financial position and liquidity, and the development of the markets and the industry in which we operate are consistent

with the forward-looking statements contained in this Quarterly Report on Form 10-Q, those results or developments may not be

indicative of results or developments in subsequent periods. A number of factors could cause results and developments to differ

materially from those expressed or implied by the forward-looking statements including, without limitation, general economic and

business conditions, the behavior of other market participants, industry trends, competition, commodity prices, changes in regulation,

currency fluctuations, our ability to recover our reserves, our ability to successfully integrate acquisitions, our ability to obtain

financing to meet liquidity needs, changes in our business strategy, and political and economic uncertainty.

Forward-looking statements may, and often do, differ materially from actual results. No representation is made that any of these

statements or forecasts will come to pass or that any forecast results will be achieved. Any forward-looking statements in this

Quarterly Report on Form 10-Q speak only as of the date of this Quarterly Report on Form 10-Q, reflect our current view with respect

to future events and are subject to risks relating to future events and other risks, uncertainties and assumptions relating to our

operations, results of operations, growth strategy and liquidity. Investors should specifically consider the factors identified in this

Quarterly Report on Form 10-Q and in other documents that we file with or furnish to the SEC which could cause actual results to

differ. We explicitly disclaim any obligation or undertaking to revise any forward-looking statements in this Quarterly Report on Form

10-Q that may occur due to any change in our expectations or to reflect events or circumstances after the date of this Quarterly Report

on Form 10-Q except as may be required by applicable law.