June 8, 2026 - Alliance Resource Partners, L.P. (NASDAQ: ARLP) ("ARLP" or the "Partnership") has announced that it has entered into definitive agreements to acquire certain general partner and limited partner interests in AllDale Minerals III, LP and AllDale Minerals IV, LP (collectively, "AllDale III & IV") for approximately $206.2 million, subject to customary closing price adjustments.

The transaction implies an aggregate gross valuation for AllDale III & IV of approximately $410.0 million. The general partner and limited partner interests being sold by the third-party selling interest holders are valued at approximately $306.2 million, with $206.2 million of the interests to be acquired by ARLP and $100.0 million of the interests to be acquired by related parties of Joseph W. Craft III, ARLP’s Chairman, President and Chief Executive Officer.

The difference between the $410.0 million aggregate gross valuation and the $306.2 million value of interests being acquired reflects existing interests already owned by ARLP and related parties of Mr. Craft.

Upon closing, ARLP’s aggregate economic interest across AllDale III & IV is expected to increase from approximately 5% to 61% and ARLP, through a wholly owned subsidiary, is expected to own 100% of the general partner interests of AllDale III & IV, that will be non-economic post-closing.

The agreements provide for an effective date of April 1, 2026, and the transaction is expected to close during July 2026, subject to customary closing conditions. Given the participation in the transaction by related parties of Mr. Craft, the terms of the transaction were approved by the conflicts committee of the Board of Directors of ARLP's general partner, which is comprised entirely of independent directors.

AllDale III & IV Acquisition Highlights

• AllDale III & IV hold approximately 48,500 net royalty acres ("NRAs") across premier basins and resource plays including the Permian, Anadarko, Bakken, and Haynesville

• The Permian represents approximately 7,300 of the NRAs and 52% of 1Q26 total royalty revenue

• Average 1Q26 production of approximately 5,940 BOE per day in total and 3,665 BOE per day net to ARLP’s economic interests(1), consisting of 27% oil, 18% NGLs, and 55% natural gas

• Approximately 67% of 1Q26 total royalty revenue was generated from oil

• The acquisition further de-risks ARLP’s existing minerals portfolio via a gross core acreage expansion with limited overlap to ARLP’s existing royalty asset base

• Meaningfully enhances ARLP’s northern Delaware, Anadarko, and Bakken positions, increasing trailing-twelve-month new wells placed on production by 59%, 78%, and 91%, respectively

• Provides entry into the Haynesville, a key natural gas resource play supporting LNG export demand

• Implied acquisition multiple on the general partner and limited partner interests being acquired by ARLP of approximately 5.0x projected next-twelve-month Adjusted EBITDA, based on commodity strip pricing as of June 5, 2026, and inclusive of existing AllDale III & IV hedges to be assumed at closing

• Expected to be immediately accretive to ARLP’s free cash flow per unit, based on current assumptions

• ARLP’s acquisition is expected to be funded through a combination of cash on hand, borrowings under ARLP’s revolving credit facility, and a new debt facility at Alliance Minerals, LLC, a wholly owned subsidiary of ARLP

• Pro forma total leverage is expected to remain below 1.0x following the closing of the transaction

Pro Forma ARLP Oil & Gas Royalties Segment Highlights

Upon closing the transaction, ARLP is expected to have:

• Control of approximately 115,680 NRAs, with over 44,770 NRAs in the Permian

• Average 1Q26 production of approximately 17,295 BOE per day in total, and 14,285 BOE per day net to ARLP’s economic interests(1)

• Exposure to 59 gross active rigs across the pro forma portfolio, including 47 gross active rigs on Permian acreage

(1) Net BOE per day attributable to ARLP’s economic interests represents ARLP’s acquired share of production after excluding noncontrolling interests.

Management Commentary

"This acquisition accelerates the continued growth of our Oil & Gas Royalties segment," said Mr. Craft. "The AllDale III & IV portfolio adds scale and development upside across multiple U.S. basins, anchored by a meaningful Permian position. It also expands our natural gas footprint with entry into the Haynesville, a resource play well-positioned to benefit from long-term LNG export demand growth."

Mr. Craft continued, "We believe this acquisition strengthens ARLP’s long-term royalty platform, broadens our exposure to high-quality operators and advances our long-term strategy of building a durable, cash-generating royalties business that complements our existing coal operations."

Cary Marshall, Senior Vice President and Chief Financial Officer, added, "The participation by related parties of Mr. Craft is expected to enhance the capital efficiency of the transaction for ARLP. We expect this structure will generate attractive risk-adjusted returns, maintain pro forma leverage below 1.0x, and preserve liquidity for future growth opportunities."

About Alliance Resource Partners, L.P.

ARLP is a diversified natural resource company that is currently the second largest coal producer in the eastern United States, supplying reliable, affordable energy domestically and internationally to major utilities, metallurgical and industrial users. ARLP also generates operating and royalty income from mineral interests it owns in strategic coal and oil & gas producing regions in the United States. In addition, ARLP is positioning itself as a reliable energy partner for the future by pursuing opportunities that support the growth and development of energy-related technologies and infrastructure.

News, unit prices and additional information about ARLP, including filings with the Securities and Exchange Commission ("SEC"), are available at www.arlp.com. For more information, contact the investor relations department of ARLP at (918) 295-7673 or via e-mail at investorrelations@arlp.com.