NATURAL RESOURCE PARTNERS LP

1. Basis of Presentation

Nature of Business

Natural Resource Partners L.P. (the "Partnership") engages principally in the business of owning, managing and leasing a diversified portfolio of mineral properties in the United States, including interests in coal and other natural resources and owns a non-controlling 49% interest in Sisecam Wyoming LLC ("Sisecam Wyoming"), a trona ore mining and soda ash production business. The Partnership is organized intotwo operating segments further described in Note6. Segment Information. The Partnership’s operations are conducted through, and its operating assets are owned by, its subsidiaries. The Partnership owns its subsidiaries throughone wholly owned operating company, NRP (Operating) LLC ("Opco"). As used in these Notes to Consolidated Financial Statements, the terms "NRP," "we," "us" and "our" refer to Natural Resource Partners L.P. and its subsidiaries, unless otherwise stated or indicated by context.

Principles of Consolidation and Reporting

The accompanying unaudited Consolidated Financial Statements of the Partnership have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") for interim financial information and with Rule10-01 of Regulation S-X. Accordingly, they donot include all of the information and footnotes required by GAAP for complete financial statements. These financial statements should be read in conjunction with the financial statements for the year ended* December 31, 2024* and notes thereto included in the Partnership's Annual Report on Form10-K, which was filed with the SEC on* February 28, 2025.Reclassifications have been made to prior year amounts in the Consolidated Financial Statements to conform with current year presentation. These reclassifications hadno* impact on previously reported total assets, total liabilities, partners' capital, net income, or cash flows from operating, investing or financing activities.

Recently Issued Accounting Standard

In* November 2024,the FASB issued ASU2024*-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures ("ASU2024-03"). ASU2024-03 is intended to improve disclosures about a public business entity's expenses and provide more detailed information to investors about the types of expenses in commonly presented expense captions. The guidance is effective for annual periods beginning after* December 15, 2026and quarterly periods beginning after December 31, 2027and can be adopted prospectively to financial statements issued for reporting periods after the effective date or retrospectively to all prior periods presented in the financial statements. NRP doesnot* expect the adoption of this guidance to have a material impact on its Consolidated Financial Statements.

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2. Revenues from Contracts with Customers

The following table presents the Partnership's Mineral Rights segment revenues from contracts with customers by major source:

The following table details the Partnership's Mineral Rights segment contract assets and liabilities resulting from contracts with customers:

The following table shows the activity related to the Partnership's Mineral Rights segment deferred revenue resulting from contracts with customers:

The Partnership's non-cancellable annual minimum payments due under the lease terms of its coal and aggregates royalty contracts with customers are as follows as of* September 30, 2025* (in thousands):

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3. Class A Convertible Preferred Units and Warrants

During thethree months ended* September**30,* 2024, the Partnership redeemed 31,666 Class A Convertible Preferred Units (the "preferred units") for $31.7 million in cash. During thenine months ended* September 30, 2024,the Partnership redeemed a total of 71,666 preferred units for $71.7 million in cash. In2024,* all remaining preferred units were redeemed andnone of the Partnership's preferred units remained outstanding as of* September 30, 2025* and* December 31, 2024*.

During thenine months ended* September**30,* 2024, the Partnership settled a total of 1,540,000 warrants to purchase common units ("warrants") with a strike price of $34.00. These warrants were settled on a net basis for a total of $65.7 million in cash and 287,826 common units. In2024, all remaining warrants were settled andnone of the Partnership's warrants remained outstanding as of* September 30, 2025* and* December 31, 2024*.

4. Common and Preferred Unit Distributions

The Partnership makes cash distributions to common unitholders and made cash distributions to preferred unitholders on a quarterly basis, subject to approval by the Board of Directors of GP Natural Resource Partners LLC (the "Board of Directors"). NRP recognizes common unit distributions on the date the distribution is declared. In2024, the Partnership recognized preferred unit distributions on the date the distribution was declared.

Distributions made on the common units and the general partner's general partner ("GP") interest are made on a pro-rata basis in accordance with their relative percentage interests in the Partnership. The general partner is entitled to receive 2% of such distributions.

Income available to common unitholders and the general partner was reduced by $0.7 million and $4.2 million in preferred unit distributions that accumulated during thethree andnine months ended* September 30, 2024*, respectively. Income available to common unitholders and the general partner was also reduced by $10.8 million and $24.5 million during thethree andnine months ended* September**30,* 2024, respectively, which represents the difference between the fair value of the consideration paid upon redemption of the preferred units and the carrying value of the preferred units.

The following table shows the cash distributions declared and paid to common and preferred unitholders during thenine months ended* September 30, 2025and2024*, respectively:

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5. Net Income Per Common Unit

In2025, basic net income per common unit is computed by dividing net income, after considering the general partner’s general partner interest, by the weighted average number of common units outstanding. Diluted net income per common unit includes the effect of NRP's unvested unit-based awards if the inclusion of these items is dilutive.

In2024, basic net income per common unit is computed by dividing net income, after considering income attributable to preferred unitholders, the difference between the fair value of the consideration paid upon redemption and the carrying value of the preferred units, and the general partner’s general partner interest, by the weighted average number of common units outstanding. Diluted net income per common unit includes the effect of NRP's preferred units, warrants, and unvested unit-based awards if the inclusion of these items is dilutive.

The dilutive effect of the preferred units in2024 was calculated using the if-converted method. Under the if-converted method, the preferred units were assumed to be converted at the beginning of the period, and the resulting common units were included in the denominator of the diluted net income per unit calculation for the period being presented. Distributions declared in the period and undeclared distributions on the preferred units that accumulated during the period were added back to the numerator for purposes of the if-converted calculation. The calculation of diluted net income for thethree months ended* September 30, 2024didnot* include the assumed conversion of any remaining preferred units as all preferred units were redeemed as of* September 30, 2024.The calculation of diluted net income per common unit for thenine* months ended* September 30, 2024* included the assumed conversion of the remaining preferred units during the period. The calculation of diluted net income for thethree andnine months ended* September**30,* 2024 didnot include the assumed conversion of the preferred units that were redeemed during the period as the inclusion of these units would be anti-dilutive.

The dilutive effect of the warrants in2024 was calculated using the treasury stock method, which assumed that the proceeds from the exercise of these instruments were used to purchase common units at the average market price for the period. The dilutive effect of the warrants wasnot factored in to the calculation of diluted net income per common unit for thethree months* September 30, 2024as they were fully settled as of June 30, 2024.The calculation of diluted net income per common unit for thenine* months ended* September 30, 2024*included the net settlement of the warrants for the period during which they were outstanding.

The dilutive effect of the unvested unit-based awards is calculated using the treasury stock method, which assumes that the proceeds from the vesting of the unvested unit-based awards are used to purchase common units at the average market price for the period. The calculation of diluted net income per common unit for thethree andnine months ended* September 30, 2025and2024* included the impact of the vesting of the unvested unit-based awards.

The following table reconciles the numerator and denominator of the basic and diluted net income per common unit computations and calculates basic and diluted net income per common unit:

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6. Segment Information

The Partnership's segments are strategic business units that offer distinct products and services to different customers in different geographies within the U.S. and that are managed accordingly. NRP has the followingtwo operating segments:

Mineral Rights—consists of mineral interests and other subsurface rights across the United States. NRP's ownership provides critical inputs for the manufacturing of steel, electricity, and basic building materials, as well as opportunities for carbon sequestration and renewable energy.

Soda Ash—consists of the Partnership's 49% non-controlling equity interest in Sisecam Wyoming,one of the world's lowest-cost producers of soda ash, an essential ingredient for the manufacturing of glass, detergents, solar panels, and batteries for electric vehicles. Operations are managed by NRP's partner, Sisecam Chemicals Wyoming, LLC, and NRP realizes cash flow when distributions are paid to it.

Direct segment costs and certain other costs incurred at the corporate level that are identifiable and that benefit the Partnership's segments are allocated to the operating segments accordingly. These allocated costs generally include salaries and benefits, insurance, property taxes, legal, royalty, information technology and shared facilities services and are included in operating and maintenance expenses on the Partnership's Consolidated Statements of Comprehensive Income.

Corporate and Financing includes functional corporate departments that donot earn revenues. Costs incurred by these departments include interest and financing, corporate headquarters and overhead, centralized treasury, legal and accounting and other corporate-level activitynot specifically allocated to a segment and are included in general and administrative expenses on the Partnership's Consolidated Statements of Comprehensive Income.

NRP’s Chief Operating Decision Makers (“CODMs”) are its Chief Executive Officer and President and Chief Operating Officer. They evaluate the Partnership’s performance through a review of the segments’ net income and free cash flow as compared to budget and utilize this information to assess the segments’ performance and allocate resources. NRP doesnot conduct operations on any of its assets or directly engage in any type of industrial activity. Instead, it leases its mineral and other rights to companies that conduct operations on its properties in exchange for paying royalties and other fees to the Partnership. Operating expenses, capital costs and other liabilities arising out of production activities are borne entirely by NRP's lessees. In the case of its soda ash investment, operations are managed by NRP's partner, Sisecam Chemicals Wyoming LLC. NRP has determined its significant segment expenses to be its employee related expenses, including compensation (salaries, benefits and bonus) and long-term incentive compensation as well as interest expense and property tax expense. The Partnership is responsible for paying property taxes on the properties it owns. Typically, NRP's lessees are contractually responsible for reimbursing the Partnership for property taxes on the leased properties and this reimbursement amount is included within the Mineral Rights segment revenues. Reclassifications have been made to prior year amounts to conform with current year presentation.

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The following tables summarize certain financial information for each of the Partnership's business segments:

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7. Equity Investment

The Partnership accounts for its 49% investment in Sisecam Wyoming using the equity method of accounting. Activity related to this investment is as follows:

The following table represents summarized financial information for Sisecam Wyoming as derived from their respective unaudited financial statements for thethree andnine months ended* September 30, 2025and2024*:

8. Mineral Rights, Net

The Partnership’s mineral rights consist of the following:

Depletion expense related to the Partnership’s mineral rights is included in depreciation, depletion and amortization on its Consolidated Statements of Comprehensive Income and totaled $3.8 million and $4.7 million for thethree months ended* September 30, 2025* and2024, respectively, and $11.0 million and $12.1 million for thenine months ended* September**30,* 2025 and2024, respectively.

The Partnership has developed procedures to evaluate its long-lived assets for possible impairment periodically or whenever events or changes in circumstances indicate an asset's net book value* may**not* be recoverable. Potential events or circumstances include, but arenot limited to, specific events such as a reduction in economically recoverable minerals or production ceasing on a property for an extended period. This analysis is based on historic, current and future performance and considers both quantitative and qualitative information. As a result of the Partnership's analyses, NRP recorded an immaterial impairment expense during thenine months ended* September 30, 2025* as well as during thethree andnine months ended* September 30, 2024.*

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9. Debt, Net

The Partnership's debt consists of the following:

Opco Debt

All of Opco’s debt is guaranteed by its wholly owned subsidiaries and is secured by certain of the assets of Opco and its wholly owned subsidiaries, other than BRP LLC and NRP Trona LLC. As of* September 30, 2025* and* December 31, 2024*, Opco was in compliance with the terms of the financial covenants contained in its debt agreements.

Opco Credit Facility

In* May 2023,the Partnership entered into the Sixth Amendment (the "Sixth Amendment) to the Opco Credit Facility (the "Opco Credit Facility"). The Sixth Amendment maintained the term of the Opco Credit Facility until August 2027.Lender commitments under the Opco Credit Facility increased from $130.0 million to $155.0 million, with the ability to expand such commitments to $200.0 million with the addition of future commitments. In February 2024,the Partnership exercised its option under the Opco Credit Facility to increase the total aggregate commitment under the Opco Credit Facility twice, initially by $30.0 million from $155.0 million to $185.0 million and subsequently by $15.0 million from $185.0 million to $200.0 million. These increases in the total aggregate commitment were made pursuant to an accordion feature of the Opco Credit Facility. In connection with the initial increase, a new lender joined the lending group with a commitment of $30.0 million. In October 2024,NRP entered into the Seventh Amendment to the Opco Credit Facility which extended the maturity from August 2027to October 2029.The Seventh Amendment also removed reference to the preferred units and warrants, which areno* longer outstanding, and includes modifications to Opco's ability to declare and make certain restricted payments.

The Opco Credit Facility contains financial covenants requiring Opco to maintain:

As of* December 31, 2024*, the Partnership had $113.7 million in borrowings outstanding under the Opco Credit Facility and $86.3 million of available borrowing capacity. During thenine months ended* September 30, 2025*, the Partnership borrowed $33.7 million and repaid $106.5 million, resulting in $40.9 million in borrowings outstanding under the Opco Credit Facility and $159.1 million of available borrowing capacity as of* September 30, 2025*. During thenine months ended* September 30, 2024*, the Partnership borrowed $152.9 million and repaid $94.0 million on the Opco Credit Facility. The weighted average interest rate for the borrowings outstanding under the Opco Credit Facility for thethree months ended* September 30, 2025and2024* was 7.93% and 8.91%, respectively. The weighted average interest rate for the borrowings outstanding under the Opco Credit Facility for thenine months ended* September 30, 2025and2024* was 7.93% and 8.92%, respectively.

The Opco Credit Facility is collateralized and secured by liens on certain of Opco’s assets with carrying values of $293.0 million and $302.8 million classified as mineral rights, net and other long-term assets, net and $21.2 million and $23.5 million classified as long-term contract receivable, net on the Partnership’s Consolidated Balance Sheets as of* September 30, 2025* and* December 31, 2024*, respectively.

Opco Senior Notes

Opco issued several series of private placement senior notes (the "Opco Senior Notes") with various interest rates and principal due dates. As of* September 30, 2025*, the5.03% and5.18% Opco Senior Notes remain outstanding. These Opco Senior Notes have principal due annually in* Decemberand interest due semi-annually in Juneand December.As of both September 30, 2025* and* December 31, 2024*, the Opco Senior Notes had cumulative principal balances of $28.7 million. Opco made mandatory principal payments of $0.0 million and $16.7 during thenine months ended* September 30, 2025and2024*, respectively. These Opco Senior Notes will fully mature in* December 2026.*

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10. Fair Value Measurements

Fair Value of Financial Assets and Liabilities

The Partnership’s financial assets and liabilities consist of cash and cash equivalents, a contract receivable and debt. The carrying amounts reported on the Consolidated Balance Sheets for cash and cash equivalents approximate fair value due to their short-term nature. The Partnership uses available market data and valuation methodologies to estimate the fair value of its contract receivable and debt.

The following table shows the carrying value and estimated fair value of the Partnership's contract receivable and debt:

11. Related Party Transactions

Affiliates of our General Partner

The Partnership’s general partner doesnot receive any management fee or other compensation for its management of NRP. However, in accordance with the partnership agreement, the general partner and its affiliates are reimbursed for services provided to the Partnership and for expenses incurred on the Partnership’s behalf. Employees of Quintana Minerals Corporation ("QMC") and Western Pocahontas Properties Limited Partnership ("WPPLP"), affiliates of the Partnership, provide their services to manage the Partnership's business. QMC and WPPLP charge the Partnership the portion of their employee salary and benefits costs related to their employee services provided to NRP. These QMC and WPPLP employee management service costs are presented as operating and maintenance expenses and general and administrative expenses on the Partnership's Consolidated Statements of Comprehensive Income. NRP also reimburses overhead costs incurred by its affiliates, and other related parties, to manage the Partnership's business. These overhead costs include certain rent, information technology, administration of employee benefits and other corporate services incurred by or on behalf of the Partnership’s general partner and its affiliates and are presented as operating and maintenance expenses and general and administrative expenses on the Partnership's Consolidated Statements of Comprehensive Income.

Related party general and administrative expenses included on the Partnership's Consolidated Statement of Comprehensive Income are as follows:

The Partnership had accounts payable to related parties of $0.5 million and $0.6 million on its Consolidated Balance Sheets at* September 30, 2025* and* December 31, 2024,respectively. The Partnership had other current assets of $0.1 and $0.2 million on its Consolidated Balance Sheets related to a prepaid expense at September 30, 2025* and* December 31, 2024*, respectively.

As a result of its office lease with WPPLP, the Partnership has a right-of-use asset and lease liability of $3.4 million included in other long-term assets, net and other non-current liabilities, respectively on its Consolidated Balance Sheets at both* September 30, 2025* and* December 31, 2024*.

During thethree months ended* September 30, 2025and2024*, the Partnership recognized $0.1 million and $0.01 million in operating and maintenance expenses, respectively, on its Consolidated Statements of Comprehensive Income related to an overriding royalty agreement with WPPLP. These amounts were $0.3 million and $0.05 million during thenine months ended* September**30,* 2025 and2024, respectively. The Partnership had $0.1 million in accounts payable on its Consolidated Balance Sheets at* September 30, 2025* related to this agreement as well as $1.1 million and $0.5 million of other long-term assets, net on its Consolidated Balance Sheets related to a prepaid royalty for this agreement at* September 30, 2025* and* December 31, 2024,*respectively.

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12. Major Customers

Revenues from customers that exceeded10 percent of total revenues for any of the periods presented below are as follows:

13. Commitments and Contingencies

NRP is involved, from time to time, in various legal proceedings arising in the ordinary course of business. While the ultimate results of these proceedings cannot be predicted with certainty, Partnership management believes these ordinary course matters willnot have a material effect on the Partnership’s financial position, liquidity or operations as of and for thethree andnine months ended* September 30, 2025.*

14. Unit-Based Compensation

During thenine months ended* September 30, 2025and2024*, the Partnership granted service, performance and market-based awards under its2017 Long-Term Incentive Plan. The Partnership's service and performance-based awards are valued using the closing price of NRP's common units as of the grant date while the Partnership's market-based awards are valued using a Monte Carlo simulation. The grant date fair value of the awards granted during thenine months ended* September 30, 2025and2024* was $6.8 million and $6.7 million, respectively, which included a grant date fair value of $2.5 million for the market-based awards valued using a Monte Carlo simulation during both thenine months ended* September 30, 2025* and2024. Total unit-based compensation expense associated with service, performance and market-based awards was $2.7 million and $3.0 million for thethree months ended* September 30, 2025* and2024, respectively, and $8.1 million and $8.9 million for thenine months ended* September**30,* 2025 and2024, respectively, and is included in general and administrative expenses and operating and maintenance expenses on the Partnership's Consolidated Statements of Comprehensive Income. The unamortized cost associated with unvested outstanding awards as of* September 30, 2025* was $9.2 million, which will be recognized over a weighted average period of 1.7 years. The unamortized cost associated with unvested outstanding awards as of* December 31, 2024* was $9.5 million. The Partnership paid $5.5 million and $6.4 million in cash during thenine months ended* September 30, 2025* and2024, respectively, for taxes on the unit-based award settlements during the respective years. These cash payments are included in other items, net under cash flows from financing activities on the Partnership's Consolidated Statements of Cash Flows.

A summary of the unit activity in the outstanding grants during2025 is as follows:

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15. Credit Losses

The Partnership is exposed to credit losses through collection of its short-term trade receivables resulting from contracts with customers and a long-term receivable resulting from a financing transaction with a customer. The Partnership records an allowance for current expected credit losses on these receivables based on the loss-rate method. NRP assessed the likelihood of collection of its receivables utilizing historical loss rates, current market conditions, industry and macroeconomic factors, reasonable and supportable forecasts and facts or circumstances of individual customers and properties. Examples of these facts or circumstances include, but arenot limited to, contract disputes or renegotiations with the customer and evaluation of short and long-term economic viability of the contracted property. For its long-term contract receivable, management reverts to the historical loss experience immediately after the reasonable and supportable forecast period ends.

As of* September 30, 2025* and* December 31, 2024*, NRP had the following current expected credit loss (“CECL”) allowance related to its receivables and long-term contract receivable:

NRP recorded $1.7 million and $0.7 million of operating and maintenance expenses on its Consolidated Statements of Comprehensive Income related to the change in the CECL allowance during thethree months ended* September 30, 2025* and2024, respectively, and $0.03 million and a reversal of $0.1 million of operating and maintenance expenses during thenine months ended* September**30,* 2025 and2024, respectively.

NRP has procedures in place to monitor its ongoing credit exposure through timely review of counterparty balances against contract terms and due dates, account and financing receivable reconciliation, bankruptcy monitoring, lessee audits and dispute resolution. The Partnership* may*employ legal counsel or collection specialists to pursue recovery of defaulted receivables.

16. Subsequent Events

The following represents material events that have occurred subsequent to* September 30, 2025* through the time of the Partnership’s filing of its Quarterly Report on Form10-Q with the SEC:

Common Unit Distributions

In* November 2025,the Board of Directors declared a distribution of $0.75 per common unit with respect to thethird* quarter of2025.

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