Mach Natural Resources LP (NYSE:MNR) ("Mach" or the "Company") announced today the proposed underwritten public offering (the "Offering") of 9,000,000 common units representing limited partner interests in Mach (the "common units") by VEPU Inc., Simlog Inc. and Sabinal Energy Operating, LLC (the "Selling Unitholders"). Mach will not sell any common units in the Offering and will not receive any proceeds therefrom. The Offering is subject to market and other conditions, and there can be no assurance as to whether or when the Offering may be completed. The Selling Unitholders have granted the underwriters a 30-day option to purchase up to an additional 1,350,000 common units.

Morgan Stanley is acting as the underwriter for the Offering. The Offering of these securities is being made only by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended. When available, a copy of the preliminary prospectus may be obtained by contacting: Morgan Stanley & Co. LLC, Attn: Prospectus Department, 180 Varick Street, 2nd Floor, New York, New York 10014.

Important Information

The Offering is being made pursuant to a registration statement previously filed by the Company with the Securities and Exchange Commission (the "SEC") that became effective on December 12, 2025. The Offering may be made only by means of a prospectus supplement and accompanying prospectus. Copies of the preliminary prospectus supplement and accompanying prospectus related to the Offering can be obtained by visiting the SEC's website at www.sec.gov under "Mach Natural Resources LP." This press release does not constitute an offer to sell or the solicitation of an offer to buy securities, and shall not constitute an offer, solicitation or sale in any jurisdiction in which such offer, solicitation or sale would be unlawful.

About Mach Natural Resources LP

Mach Natural Resources LP is an independent upstream oil and gas company focused on the acquisition, development and production of oil, natural gas and NGL reserves. The Company operates a diversified portfolio across the Anadarko, Permian and San Juan Basins.

Cautionary Note Regarding Forward-Looking Statements

This press release contains statements that express the Company's opinions, expectations, beliefs, plans, objectives, assumptions or projections regarding future events or future results, in contrast with statements that reflect historical facts. All statements, other than statements of historical fact included in this press release regarding our strategy, future operations, financial position, estimated revenues and losses, projected costs, prospects, plans and objectives of management are forward-looking statements including, but not limited to, statements regarding the completion of the Offering. When used in this press release, words such as "may," "assume," "forecast," "could," "should," "will," "plan," "believe," "anticipate," "intend," "estimate," "expect," "project," "budget" and similar expressions are used to identify forward-looking statements, although not all forward-looking statements contain such identifying words. Specific forward-looking statements include statements regarding the Company's projected results of operating, financial position, growth opportunities and reserve estimates. These forward-looking statements are based on management's current belief, based on currently available information as to the outcome and timing of future events at the time such statement was made. Such statements are subject to a number of assumptions, risk and uncertainties, many of which are beyond the control of the Company. These include, but are not limited to, risks associated with respect to the timing, terms and completion of the Offering, the Company's future financial condition, results of operations and ability to achieve the guidance provided, strategy and plans; the ability of the Company to realize anticipated synergies related to the closing of the Permian Basin and San Juan Basin transactions in the timeframe expected or at all; changes in markets and the ability of the Company to finance operations in the manner expected; commodity price volatility; the impact of epidemics, outbreaks or other public health events, and the related effects on financial markets, worldwide economic activity and our operations; uncertainties about our estimated oil, natural gas and natural gas liquids reserves, including the impact of commodity price declines on the economic producibility of such reserves, and in projecting future rates of production; difficult and adverse conditions in the domestic and global capital and credit markets; lack of transportation and storage capacity as a result of oversupply, government regulations or other factors; lack of availability of drilling and production equipment and services; potential financial losses or earnings reductions resulting from our commodity price risk management program or any inability to manage our commodity risks; failure to realize expected value creation from property acquisitions and trades; access to capital and the timing of development expenditures; environmental, weather, drilling and other operating risks; regulatory changes, including potential shut-ins or production curtailments mandated by the Railroad Commission of Texas, the Oklahoma Corporation Commission and/or the Kansas Corporation Commission; competition in the oil and natural gas industry; loss of production and leasehold rights due to mechanical failure or depletion of wells and our inability to re-establish their production; our ability to service our indebtedness; any downgrades in our credit ratings that could negatively impact our cost of and ability to access capital; cost inflation; the potential for significant new tariffs and their impact on global oil, natural gas and NGL markets; political and economic conditions and events in foreign oil and natural gas producing countries, including embargoes, continued hostilities in the Middle East and other sustained military campaigns, the war in Ukraine and associated economic sanctions on Russia, conditions in South America, Central America, China and Russia, and acts of terrorism or sabotage; evolving cybersecurity risks such as those involving unauthorized access, denial-of-service attacks, malicious software, data privacy breaches by employees, insiders or others with authorized access, cyber or phishing-attacks, ransomware, social engineering, physical breaches or other actions; and risks related to our ability to expand our business, including through the recruitment and retention of qualified personnel. Although management believes its assumptions to be reasonable, due to various known and unknown risks, there can be no assurance that the projected results will be achieved and there is a substantial likelihood that the actual results of the Company's operations will differ materially from the projections. Please read the Company's filings with the SEC, including "Risk Factors" in the prospectus supplement and the Company's Annual Report on Form 10-K, which are on file with the SEC, for a discussion of risks and uncertainties that could cause actual results to differ from those in such forward-looking statements.

As a result, these forward-looking statements are not a guarantee of our performance, and you should not place undue reliance on such statements. Any forward-looking statement speaks only as of the date on which such statement is made, and the Company undertakes no obligation to correct or update any forward-looking statement, whether as a result of new information, future events or otherwise.

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FOR FURTHER INFORMATION, PLEASE CONTACT:

Mach Natural Resources LP

Investor Relations Contact: ir@machnr.com

Mach Natural Resources LP Announces Secondary Public Offering of Common Units