0001171486 NATURAL RESOURCE PARTNERS LP false --12-31 Q1 2025 13,138,097 13,138,097 13,049,123 13,049,123 2 1 0 2 2 5.03 5.03 5.18 5.18 3.0 0.6 13.6 28.7 15 3.4 0.5 http://fasb.org/us-gaap/2025#OtherAssetsNoncurrent http://fasb.org/us-gaap/2025#OtherAssetsNoncurrent http://fasb.org/us-gaap/2025#OtherLiabilitiesNoncurrent http://fasb.org/us-gaap/2025#OtherLiabilitiesNoncurrent 2.5 false false false false Lease term does not include renewal periods. The fair value of the Opco Credit Facility approximates the outstanding borrowing amount because the interest rates are variable and reflective of market rates and the terms of the credit facility allow the Partnership to repay the debt at any time without penalty. Other segment items in the Mineral Rights segment primarily include: insurance, legal, overriding royalty expense, processing and transportation expense, information technology, shared facility services, rent and professional fees. Other segment items in the Soda Ash segment primarily include professional fees. Other segment items in the Corporate and Financing segment primarily include: insurance, legal, information technology, shared facility services, rent and professional fees. Amounts reclassified into income out of accumulated other comprehensive income was $1.3 million for the three months ended March 31, 2025. Amounts reclassified into income out of accumulated other comprehensive loss was $1.6 million for the three months ended March 31, 2024. Special distribution was made to help cover unitholder tax liabilities associated with owning NRP's common units during 2023. Special distribution was made to help cover unitholder tax liabilities associated with owning NRP's common units during 2024. Revenues from Alpha Metallurgical Resources, Inc. and Foresight are included within the Partnership's Mineral Rights segment. Net income includes $2.15 million of income attributable to preferred unitholders that accumulated during the period, of which $2.11 million is allocated to the common unitholders and $0.04 million is allocated to the general partner. Long-term incentive compensation for the three months ended March 31, 2025 includes (1) Mineral Rights segment: $0.3 million of equity compensation and $0.1 million of cash compensation; (2) Corporate & Financing segment: $2.2 million of equity compensation and $0.1 of cash compensation. Totals include the amount paid to NRP's general partner in accordance with the general partner's 2% general partner interest. The fair value of the Opco Senior Notes was estimated by management utilizing the present value replacement method incorporating the interest rate of the Opco Credit Facility. 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Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

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

For the quarterly period ended March 31, 2025 or

☐ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|  | Commission file number: | 001-31465 |

NATURAL RESOURCE PARTNERS LP
| (Exact name of registrant as specified in its charter) |

Delaware | 35-2164875
(State or other jurisdiction of incorporation or organization) | (I.R.S. Employer Identification No.)

1415 Louisiana Street, Suite 3325

Houston, Texas 77002

(Address of principal executive offices)

(Zip Code)

(713) 751-7507

(Registrant’s telephone number, including area code)

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

Title of each class |  | Trading Symbol(s) |  | Name of each exchange on which registered
Common Units representing limited partner interests |  | NRP |  | New York Stock Exchange

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 ☒ 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 ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See definition of "accelerated filer", "large accelerated filer", "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large Accelerated Filer | ☒ | Accelerated Filer |  | ☐
Non-accelerated Filer | ☐ | Smaller Reporting Company |  | ☐
|  | Emerging Growth Company |  | ☐

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 ☐ No ☒

APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY PROCEEDINGS DURING THE PRECEDING FIVE YEARS:

Indicate by check mark whether the registrant has filed all documents and reports required to be filed by Section 12, 13 or 15(d) of the Securities Exchange Act of 1934 subsequent to the distribution of securities under a plan confirmed by a court. Yes ☐ No ☐

APPLICABLE ONLY TO CORPORATE ISSUERS

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date.

Table of Contents

NATURAL RESOURCE PARTNERS, L.P.

TABLE OF CONTENTS

|  | Page
Part I. Financial Information
Item 1. | Consolidated Financial Statements |
| Consolidated Balance Sheets | 1
| Consolidated Statements of Comprehensive Income | 2
| Consolidated Statements of Partners’ Capital | 3
| Consolidated Statements of Cash Flows | 4
| Notes to Consolidated Financial Statements | 5
Item 2. | Management’s Discussion and Analysis of Financial Condition and Results of Operations | 16
Item 3. | Quantitative and Qualitative Disclosures About Market Risk | 25
Item 4. | Controls and Procedures | 25
Part II. Other Information
Item 1. | Legal Proceedings | 26
Item 1A. | Risk Factors | 26
Item 2. | Unregistered Sales of Equity Securities and Use of Proceeds | 26
Item 3. | Defaults Upon Senior Securities | 26
Item 4. | Mine Safety Disclosures | 26
Item 5. | Other Information | 26
Item 6. | Exhibits | 26
| Signatures | 27

i

Table of Contents

PART I. FINANCIAL INFORMATION

ITEM 1. CONSOLIDATED FINANCIAL STATEMENTS

NATURAL RESOURCE PARTNERS L.P.

CONSOLIDATED BALANCE SHEETS

|  | March 31, |  |  | December 31, |
|  | 2025 |  |  | 2024 |
(In thousands, except unit data) |  | (Unaudited) |  |  |  |
ASSETS |  |  |  |  |  |  |  |
Current assets |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 30,876 |  |  | $ | 30,444 |
Accounts receivable, net |  |  | 31,387 |  |  |  | 31,469 |
Other current assets, net |  |  | 2,137 |  |  |  | 1,961 |
Total current assets |  | $ | 64,400 |  |  | $ | 63,874 |
Land |  |  | 24,008 |  |  |  | 24,008 |
Mineral rights, net |  |  | 377,245 |  |  |  | 379,638 |
Intangible assets, net |  |  | 12,602 |  |  |  | 12,924 |
Equity in unconsolidated investment |  |  | 261,286 |  |  |  | 257,355 |
Long-term contract receivable, net |  |  | 22,734 |  |  |  | 23,480 |
Other long-term assets, net |  |  | 10,198 |  |  |  | 11,628 |
Total assets |  | $ | 772,473 |  |  | $ | 772,907 |
LIABILITIES AND CAPITAL |  |  |  |  |  |  |  |
Current liabilities |  |  |  |  |  |  |  |
Accounts payable |  | $ | 1,455 |  |  | $ | 909 |
Accrued liabilities |  |  | 5,098 |  |  |  | 12,121 |
Accrued interest |  |  | 556 |  |  |  | 302 |
Current portion of deferred revenue |  |  | 4,949 |  |  |  | 4,341 |
Current portion of long-term debt, net |  |  | 14,210 |  |  |  | 14,192 |
Total current liabilities |  | $ | 26,268 |  |  | $ | 31,865 |
Deferred revenue |  |  | 51,979 |  |  |  | 55,814 |
Long-term debt, net |  |  | 124,594 |  |  |  | 127,876 |
Other non-current liabilities |  |  | 5,275 |  |  |  | 6,244 |
Total liabilities |  | $ | 208,116 |  |  | $ | 221,799 |
Commitments and contingencies (see Note 13) |  |  |  |  |  |  |  |
Partners’ capital |  |  |  |  |  |  |  |
Common unitholders’ interest (13,138,097 and 13,049,123 units issued and outstanding at March 31, 2025 and December 31, 2024, respectively) |  | $ | 553,754 |  |  | $ | 543,231 |
General partner’s interest |  |  | 10,013 |  |  |  | 9,547 |
Accumulated other comprehensive income (loss) |  |  | 590 |  |  |  | (1,670 | )
Total partners’ capital |  | $ | 564,357 |  |  | $ | 551,108 |
Total liabilities and partners' capital |  | $ | 772,473 |  |  | $ | 772,907 |

The accompanying notes are an integral part of these consolidated financial statements.

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NATURAL RESOURCE PARTNERS L.P.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(Unaudited)

|  | For the Three Months Ended March 31, |
(In thousands, except per unit data) |  | 2025 |  |  | 2024 |
Revenues and other income |  |  |  |  |  |  |  |
Royalty and other mineral rights |  | $ | 51,260 |  |  | $ | 67,372 |
Transportation and processing services |  |  | 4,421 |  |  |  | 3,427 |
Equity in earnings of Sisecam Wyoming |  |  | 4,610 |  |  |  | 5,450 |
Gain on asset sales and disposals |  |  | 247 |  |  |  | 165 |
Total revenues and other income |  | $ | 60,538 |  |  | $ | 76,414 |
Operating expenses |  |  |  |  |  |  |  |
Operating and maintenance expenses |  | $ | 6,776 |  |  | $ | 5,733 |
Depreciation, depletion and amortization |  |  | 3,989 |  |  |  | 4,654 |
General and administrative expenses |  |  | 6,832 |  |  |  | 6,327 |
Asset impairments |  |  | 20 |  |  |  | — |
Total operating expenses |  | $ | 17,617 |  |  | $ | 16,714 |
Income from operations |  | $ | 42,921 |  |  | $ | 59,700 |
Interest expense, net |  | $ | (2,668 | ) |  | $ | (3,487 | )
Net income |  | $ | 40,253 |  |  | $ | 56,213 |
Less: income attributable to preferred unitholders |  |  | — |  |  |  | (2,150 | )
Net income attributable to common unitholders and the general partner |  | $ | 40,253 |  |  | $ | 54,063 |
Net income attributable to common unitholders |  | $ | 39,448 |  |  | $ | 52,982 |
Net income attributable to the general partner |  |  | 805 |  |  |  | 1,081 |
Net income per common unit (see Note 5) |  |  |  |  |  |  |  |
Basic |  | $ | 3.01 |  |  | $ | 4.13 |
Diluted |  |  | 2.97 |  |  |  | 3.83 |
Net income |  | $ | 40,253 |  |  | $ | 56,213 |
Comprehensive income from unconsolidated investment and other |  |  | 2,260 |  |  |  | 845 |
Comprehensive income |  | $ | 42,513 |  |  | $ | 57,058 |

The accompanying notes are an integral part of these consolidated financial statements.

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NATURAL RESOURCE PARTNERS L.P.

CONSOLIDATED STATEMENTS OF PARTNERS’ CAPITAL

(Unaudited)

|  |  |  |  |  |  |  |  |  |  |  |  |  | Accumulated |  |  |  |  |
|  |  |  |  |  |  |  |  |  |  |  |  |  | Other |  |  | Total |
|  | Common Unitholders |  |  | General |  |  | Comprehensive |  |  | Partners' |
(In thousands) |  | Units |  |  | Amounts |  |  | Partner |  |  | Income (Loss) |  |  | Capital |
Balance at December 31, 2024 |  |  | 13,049 |  |  | $ | 543,231 |  |  | $ | 9,547 |  |  | $ | (1,670 | ) |  | $ | 551,108 |
Net income |  |  | — |  |  |  | 39,448 |  |  |  | 805 |  |  |  | — |  |  |  | 40,253 |
Distributions to common unitholders and the general partner |  |  | — |  |  |  | (25,750 | ) |  |  | (526 | ) |  |  | — |  |  |  | (26,276 | )
Issuance of unit-based awards |  |  | 89 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Unit-based awards amortization and vesting, net |  |  | — |  |  |  | (3,175 | ) |  |  | — |  |  |  | — |  |  |  | (3,175 | )
Capital contribution |  |  | — |  |  |  | — |  |  |  | 187 |  |  |  | — |  |  |  | 187 |
Comprehensive income from unconsolidated investment and other |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 2,260 |  |  |  | 2,260 |
Balance at March 31, 2025 |  |  | 13,138 |  |  | $ | 553,754 |  |  | $ | 10,013 |  |  | $ | 590 |  |  | $ | 564,357 |

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Accumulated |  |  |  |  |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Other |  |  | Total |
|  | Common Unitholders |  |  | General |  |  | Warrant |  |  | Comprehensive |  |  | Partners' |
(In thousands) |  | Units |  |  | Amounts |  |  | Partner |  |  | Holders |  |  | Loss |  |  | Capital |
Balance at December 31, 2023 |  |  | 12,635 |  |  | $ | 503,076 |  |  | $ | 8,005 |  |  | $ | 23,095 |  |  | $ | (3,122 | ) |  | $ | 531,054 |
Net income (1) |  |  | — |  |  |  | 55,089 |  |  |  | 1,124 |  |  |  | — |  |  |  | — |  |  |  | 56,213 |
Distributions to common unitholders and the general partner |  |  | — |  |  |  | (41,342 | ) |  |  | (844 | ) |  |  | — |  |  |  | — |  |  |  | (42,186 | )
Distributions to preferred unitholders |  |  | — |  |  |  | (2,107 | ) |  |  | (43 | ) |  |  | — |  |  |  | — |  |  |  | (2,150 | )
Issuance of unit-based awards |  |  | 126 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Unit-based awards amortization and vesting, net |  |  | — |  |  |  | (3,971 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (3,971 | )
Capital contribution |  |  | — |  |  |  | — |  |  |  | 227 |  |  |  | — |  |  |  | — |  |  |  | 227 |
Warrant settlements |  |  | 199 |  |  |  | (36,650 | ) |  |  | (748 | ) |  |  | (18,291 | ) |  |  | — |  |  |  | (55,689 | )
Comprehensive income from unconsolidated investment and other |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 845 |  |  |  | 845 |
Balance at March 31, 2024 |  |  | 12,960 |  |  | $ | 474,095 |  |  | $ | 7,721 |  |  | $ | 4,804 |  |  | $ | (2,277 | ) |  | $ | 484,343 |

(1) | Net income includes $2.15 million of income attributable to preferred unitholders that accumulated during the period, of which $2.11 million is allocated to the common unitholders and $0.04 million is allocated to the general partner.

The accompanying notes are an integral part of these consolidated financial statements.

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NATURAL RESOURCE PARTNERS L.P.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

|  | For the Three Months Ended March 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Cash flows from operating activities |  |  |  |  |  |  |  |
Net income |  | $ | 40,253 |  |  | $ | 56,213 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |  |  |  |  |  |
Depreciation, depletion and amortization |  |  | 3,989 |  |  |  | 4,654 |
Distributions from unconsolidated investment |  |  | 2,940 |  |  |  | 14,210 |
Equity earnings from unconsolidated investment |  |  | (4,610 | ) |  |  | (5,450 | )
Gain on asset sales and disposals |  |  | (247 | ) |  |  | (165 | )
Asset impairments |  |  | 20 |  |  |  | — |
Bad debt expense |  |  | 451 |  |  |  | (813 | )
Unit-based compensation expense |  |  | 2,717 |  |  |  | 2,964 |
Amortization of debt issuance costs and other |  |  | (168 | ) |  |  | (749 | )
Change in operating assets and liabilities: |  |  |  |  |  |  |  |
Accounts receivable |  |  | (149 | ) |  |  | 9,433 |
Accounts payable |  |  | 546 |  |  |  | 629 |
Accrued liabilities |  |  | (7,990 | ) |  |  | (8,225 | )
Accrued interest |  |  | 254 |  |  |  | 412 |
Deferred revenue |  |  | (3,227 | ) |  |  | 1,028 |
Other items, net |  |  | (355 | ) |  |  | (2,642 | )
Net cash provided by operating activities |  | $ | 34,424 |  |  | $ | 71,499 |
Cash flows from investing activities |  |  |  |  |  |  |  |
Proceeds from asset sales and disposals |  | $ | 247 |  |  | $ | 165 |
Return of long-term contract receivable |  |  | 700 |  |  |  | 647 |
Net cash provided by investing activities |  | $ | 947 |  |  | $ | 812 |
Cash flows from financing activities |  |  |  |  |  |  |  |
Debt borrowings |  | $ | 33,700 |  |  | $ | 89,357 |
Debt repayments |  |  | (37,000 | ) |  |  | (55,696 | )
Distributions to common unitholders and the general partner |  |  | (26,276 | ) |  |  | (42,186 | )
Distributions to preferred unitholders |  |  | — |  |  |  | (2,150 | )
Warrant settlements (see Note 3) |  |  | — |  |  |  | (55,689 | )
Other items, net |  |  | (5,363 | ) |  |  | (6,946 | )
Net cash used in financing activities |  | $ | (34,939 | ) |  | $ | (73,310 | )
Net increase (decrease) in cash and cash equivalents |  | $ | 432 |  |  | $ | (999 | )
Cash and cash equivalents at beginning of period |  |  | 30,444 |  |  |  | 11,989 |
Cash and cash equivalents at end of period |  | $ | 30,876 |  |  | $ | 10,990 |
Supplemental cash flow information: |  |  |  |  |  |  |  |
Cash paid for interest |  | $ | 2,371 |  |  | $ | 2,843 |

The accompanying notes are an integral part of these consolidated financial statements.

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NATURAL RESOURCE PARTNERS L.P.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

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 into two operating segments further described in Note 6. Segment Information. The Partnership’s operations are conducted through, and its operating assets are owned by, its subsidiaries. The Partnership owns its subsidiaries through one 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 Rule 10-01 of Regulation S-X. Accordingly, they do not 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 Form 10-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 had no 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 ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures ("ASU 2024-03"). ASU 2024-03 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, 2026 and quarterly periods beginning after December 31, 2027 and 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 does not expect the adoption of this guidance to have a material impact on its Consolidated Financial Statements.

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

2. Revenues from Contracts with Customers

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

|  | For the Three Months Ended March 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Coal royalty revenues |  | $ | 35,498 |  |  | $ | 46,818 |
Production lease minimum revenues |  |  | 2,725 |  |  |  | 924 |
Minimum lease straight-line revenues |  |  | 4,050 |  |  |  | 4,171 |
Oil and gas royalty revenues |  |  | 2,444 |  |  |  | 3,640 |
Carbon neutral revenues |  |  | 595 |  |  |  | 2,161 |
Property tax revenues |  |  | 1,637 |  |  |  | 1,892 |
Wheelage revenues |  |  | 1,738 |  |  |  | 2,672 |
Coal overriding royalty revenues |  |  | 880 |  |  |  | 1,169 |
Lease amendment revenues |  |  | 655 |  |  |  | 702 |
Aggregates royalty revenues |  |  | 853 |  |  |  | 772 |
Other revenues |  |  | 185 |  |  |  | 653 |
Royalty and other mineral rights revenues |  | $ | 51,260 |  |  | $ | 65,574 |
Transportation and processing services revenues |  |  | 3,885 |  |  |  | 2,836 |
Total Mineral Rights segment revenues from contracts with customers |  | $ | 55,145 |  |  | $ | 68,410 |

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

|  | March 31, |  |  | December 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Contract assets |  |  |  |  |  |  |  |
Accounts receivable, net |  | $ | 27,235 |  |  | $ | 27,358 |
Other current assets, net |  |  | 815 |  |  |  | — |
Other long-term assets, net |  |  | 1,139 |  |  |  | 2,352 |
Contract liabilities |  |  |  |  |  |  |  |
Accounts payable |  | $ | 175 |  |  | $ | 125 |
Current portion of deferred revenue |  |  | 4,949 |  |  |  | 4,341 |
Deferred revenue |  |  | 51,979 |  |  |  | 55,814 |

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

|  | For the Three Months Ended March 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Balance at beginning of period (current and non-current) |  | $ | 60,155 |  |  | $ | 42,955 |
Increase due to minimums and lease amendment fees |  |  | 5,861 |  |  |  | 6,979 |
Recognition of previously deferred revenue |  |  | (9,088 | ) |  |  | (5,951 | )
Balance at end of period (current and non-current) |  | $ | 56,928 |  |  | $ | 43,983 |

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 March 31, 2025 (in thousands):

Lease Term (1) |  | Weighted Average Remaining Years |  |  | Annual Minimum Payments |
0 - 5 years |  |  | 2.2 |  |  | $ | 13,244 |
5 - 10 years |  |  | 5.0 |  |  |  | 16,900 |
10+ years |  |  | 11.0 |  |  |  | 26,309 |
Total |  |  | 7.1 |  |  | $ | 56,453 |

(1) | Lease term does not include renewal periods.

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

3. Warrants

During the three months ended March 31, 2024, the Partnership settled a total of 1,219,665 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 $55.7 million in cash and 198,767 common units. In 2024, all remaining warrants were settled and none of the Partnership's warrants remained outstanding as of March 31, 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. In 2024, 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 $2.2 million in preferred unit distributions that accumulated during the three months ended March 31, 2024.

The following table shows the cash distributions declared and paid to common and preferred unitholders during the three months ended March 31, 2025 and 2024, respectively:

|  |  |  | Common Units |  |  | Preferred Units |
Month Paid |  | Period Covered by Distribution |  | Distribution per Unit |  |  | Total Distribution (1) (In thousands) |  |  | Distribution per Unit |  |  | Total Distribution (In thousands) |
2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
February |  | October 1 - December 31, 2024 |  | $ | 0.75 |  |  | $ | 10,055 |  |  | $ | — |  |  | $ | — |
March (2) |  | Special Distribution |  |  | 1.21 |  |  |  | 16,221 |  |  |  | — |  |  |  | — |
2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
February |  | October 1 - December 31, 2023 |  | $ | 0.75 |  |  | $ | 9,918 |  |  | $ | 30.00 |  |  | $ | 2,150 |
March (3) |  | Special Distribution |  |  | 2.44 |  |  |  | 32,268 |  |  |  | — |  |  |  | — |

(1) | Totals include the amount paid to NRP's general partner in accordance with the general partner's 2% general partner interest.
(2) | Special distribution was made to help cover unitholder tax liabilities associated with owning NRP's common units during 2024.
(3) | Special distribution was made to help cover unitholder tax liabilities associated with owning NRP's common units during 2023.

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

5. Net Income Per Common Unit

In 2025, 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.

In 2024, 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 in 2024 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 per common unit for the three months ended March 31, 2024 included the assumed conversion of the preferred units that remained outstanding during the respective period.

The dilutive effect of the warrants in 2024 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 calculation of diluted net income per common unit for the three months ended March 31, 2024 included the net settlement of the warrants for the period during which they were outstanding.

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:

|  | For the Three Months Ended March 31, |
(In thousands, except per unit data) |  | 2025 |  |  | 2024 |
Basic net income per common unit |  |  |  |  |  |  |  |
Net income attributable to common unitholders |  | $ | 39,448 |  |  | $ | 52,982 |
Weighted average common units—basic |  |  | 13,098 |  |  |  | 12,832 |
Basic net income per common unit |  | $ | 3.01 |  |  | $ | 4.13 |
Diluted net income per common unit |  |  |  |  |  |  |  |
Weighted average common units—basic |  |  | 13,098 |  |  |  | 12,832 |
Plus: dilutive effect of preferred units |  |  | — |  |  |  | 775 |
Plus: dilutive effect of warrants |  |  | — |  |  |  | 521 |
Plus: dilutive effect of unvested unit-based awards |  |  | 206 |  |  |  | 265 |
Weighted average common units—diluted |  |  | 13,304 |  |  |  | 14,393 |
Net income |  | $ | 40,253 |  |  | $ | 56,213 |
Less: income attributable to preferred unitholders |  |  | — |  |  |  | — |
Less: redemption of preferred units |  |  | — |  |  |  | — |
Diluted net income attributable to common unitholders and the general partner |  | $ | 40,253 |  |  | $ | 56,213 |
Less: diluted net income attributable to the general partner |  |  | (805 | ) |  |  | (1,124 | )
Diluted net income attributable to common unitholders |  | $ | 39,448 |  |  | $ | 55,089 |
Diluted net income per common unit |  | $ | 2.97 |  |  | $ | 3.83 |

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

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 following two 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 do not earn revenues. Costs incurred by these departments include interest and financing, corporate headquarters and overhead, centralized treasury, legal and accounting and other corporate-level activity not 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. Together, they evaluate the Partnership’s performance monthly 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 does not 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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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

The following table summarizes certain financial information for each of the Partnership's business segments:

|  | Operating Segments |  |  |  |  |  |  |  |  |
(In thousands) |  | Mineral Rights |  |  | Soda Ash |  |  | Corporate and Financing |  |  | Total |
For the Three Months Ended March 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $ | 55,681 |  |  | $ | — |  |  | $ | — |  |  | $ | 55,681 |
Equity in earnings of Sisecam Wyoming |  |  | — |  |  |  | 4,610 |  |  |  | — |  |  |  | 4,610 |
Gain on asset sales and disposals |  |  | 247 |  |  |  | — |  |  |  | — |  |  |  | 247 |
Total revenues and other income |  | $ | 55,928 |  |  | $ | 4,610 |  |  | $ | — |  |  | $ | 60,538 |
Less: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation (salaries, benefits and bonus) |  | $ | 1,938 |  |  | $ | — |  |  | $ | 2,109 |  |  | $ | 4,047 |
Long-term incentive compensation (1) |  |  | 464 |  |  |  | — |  |  |  | 2,261 |  |  |  | 2,725 |
Property taxes |  |  | 1,792 |  |  |  | — |  |  |  | — |  |  |  | 1,792 |
Depreciation, depletion and amortization |  |  | 3,985 |  |  |  | — |  |  |  | 4 |  |  |  | 3,989 |
Asset impairments |  |  | 20 |  |  |  | — |  |  |  | — |  |  |  | 20 |
Interest expense, net (2) |  |  | — |  |  |  | — |  |  |  | 2,668 |  |  |  | 2,668 |
Other segment items (3) |  |  | 2,521 |  |  |  | 60 |  |  |  | 2,463 |  |  |  | 5,044 |
Net income (loss) |  | $ | 45,208 |  |  | $ | 4,550 |  |  | $ | (9,505 | ) |  | $ | 40,253 |
As of March 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets |  | $ | 505,073 |  |  | $ | 261,286 |  |  | $ | 6,114 |  |  | $ | 772,473 |
For the Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $ | 70,799 |  |  | $ | — |  |  | $ | — |  |  | $ | 70,799 |
Equity in earnings of Sisecam Wyoming |  |  | — |  |  |  | 5,450 |  |  |  | — |  |  |  | 5,450 |
Gain on asset sales and disposals |  |  | 165 |  |  |  | — |  |  |  | — |  |  |  | 165 |
Total revenues and other income |  | $ | 70,964 |  |  | $ | 5,450 |  |  | $ | — |  |  | $ | 76,414 |
Less: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation (salaries, benefits and bonus) |  | $ | 1,976 |  |  | $ | — |  |  | $ | 1,726 |  |  | $ | 3,702 |
Long-term incentive compensation (4) |  |  | 505 |  |  |  | — |  |  |  | 2,410 |  |  |  | 2,915 |
Property taxes |  |  | 2,167 |  |  |  | — |  |  |  | — |  |  |  | 2,167 |
Depreciation, depletion and amortization |  |  | 4,649 |  |  |  | — |  |  |  | 5 |  |  |  | 4,654 |
Interest expense, net (2) |  |  | — |  |  |  | — |  |  |  | 3,487 |  |  |  | 3,487 |
Other segment items (3) |  |  | 1,023 |  |  |  | 62 |  |  |  | 2,191 |  |  |  | 3,276 |
Net income (loss) |  | $ | 60,644 |  |  | $ | 5,388 |  |  | $ | (9,819 | ) |  | $ | 56,213 |
As of December 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets |  | $ | 509,127 |  |  | $ | 257,355 |  |  | $ | 6,425 |  |  | $ | 772,907 |

(1) | Long-term incentive compensation for the three months ended March 31, 2025 includes (1) Mineral Rights segment: $0.3 million of equity compensation and $0.1 million of cash compensation; (2) Corporate & Financing segment: $2.2 million of equity compensation and $0.1 of cash compensation.
(2) | Included in interest expense, net was $0.2 million and $0.1 million of interest income for the three months ended March 31, 2025 and 2024, respectively.
(3) | Other segment items in the Mineral Rights segment primarily include: insurance, legal, overriding royalty expense, processing and transportation expense, information technology, shared facility services, rent, professional fees and bad debt expense. Other segment items in the Soda Ash segment primarily include professional fees. Other segment items in the Corporate and Financing segment primarily include: insurance, legal, information technology, shared facility services, rent and professional fees.
(4) | Long-term incentive compensation for the three months ended March 31, 2024 includes (1) Mineral Rights segment: $0.4 million of equity compensation and $0.1 million of cash compensation; (2) Corporate & Financing segment: $2.3 million of equity compensation and $0.1 of cash compensation.

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

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:

|  | For the Three Months Ended March 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Balance at beginning of period |  | $ | 257,355 |  |  | $ | 276,549 |
Income allocation to NRP’s equity interests (1) |  |  | 5,764 |  |  |  | 6,646 |
Amortization of basis difference |  |  | (1,153 | ) |  |  | (1,196 | )
Other comprehensive income |  |  | 2,260 |  |  |  | 845 |
Distributions |  |  | (2,940 | ) |  |  | (14,210 | )
Balance at end of period |  | $ | 261,286 |  |  | $ | 268,634 |

(1) | Amounts reclassified into income out of accumulated other comprehensive loss was $1.3 million and $1.6 million for the three months ended March 31, 2025 and 2024, respectively.

The following table represents summarized financial information for Sisecam Wyoming as derived from their respective unaudited financial statements for the three months ended March 31, 2025 and 2024:

|  | For the Three Months Ended March 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Net sales |  | $ | 153,309 |  |  | $ | 130,431 |
Gross profit |  |  | 19,033 |  |  |  | 21,233 |
Net income |  |  | 11,764 |  |  |  | 13,563 |

8. Mineral Rights, Net

The Partnership’s mineral rights consist of the following:

|  | March 31, 2025 |  |  | December 31, 2024 |
(In thousands) |  | Carrying Value |  |  | Accumulated Depletion |  |  | Net Book Value |  |  | Carrying Value |  |  | Accumulated Depletion |  |  | Net Book Value |
Coal properties |  | $ | 653,808 |  |  | $ | (294,522 | ) |  | $ | 359,286 |  |  | $ | 660,961 |  |  | $ | (299,404 | ) |  | $ | 361,557 |
Aggregates properties |  |  | 8,655 |  |  |  | (4,139 | ) |  |  | 4,516 |  |  |  | 8,655 |  |  |  | (4,065 | ) |  |  | 4,590 |
Oil and gas royalty properties |  |  | 12,354 |  |  |  | (10,441 | ) |  |  | 1,913 |  |  |  | 12,354 |  |  |  | (10,394 | ) |  |  | 1,960 |
Other |  |  | 13,142 |  |  |  | (1,612 | ) |  |  | 11,530 |  |  |  | 13,143 |  |  |  | (1,612 | ) |  |  | 11,531 |
Total mineral rights, net |  | $ | 687,959 |  |  | $ | (310,714 | ) |  | $ | 377,245 |  |  | $ | 695,113 |  |  | $ | (315,475 | ) |  | $ | 379,638 |

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 $3.7 million and $4.3 million for the three months ended March 31, 2025 and 2024, 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 are not 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 the three months ended March 31, 2025.

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

9. Debt, Net

The Partnership's debt consists of the following:

|  | March 31, |  |  | December 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Opco Credit Facility |  | $ | 110,384 |  |  | $ | 113,684 |
Opco Senior Notes |  |  |  |  |  |  |  |
5.03% with semi-annual interest payments in June and December, with annual principal payments in December, due December 2026 |  | $ | 22,841 |  |  | $ | 22,841 |
5.18% with semi-annual interest payments in June and December, with annual principal payments in December, due December 2026 |  |  | 5,822 |  |  |  | 5,822 |
Total Opco Senior Notes |  | $ | 28,663 |  |  | $ | 28,663 |
Total debt at face value |  | $ | 139,047 |  |  | $ | 142,347 |
Net unamortized debt issuance costs |  |  | (243 | ) |  |  | (279 | )
Total debt, net |  | $ | 138,804 |  |  | $ | 142,068 |
Less: current portion of long-term debt |  |  | (14,210 | ) |  |  | (14,192 | )
Total long-term debt, net |  | $ | 124,594 |  |  | $ | 127,876 |

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 March 31, 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 2027 to October 2029. The Seventh Amendment also removed reference to the preferred units and warrants, which are no 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:

| • | A leverage ratio of consolidated indebtedness to EBITDDA (in each case as defined in the Opco Credit Facility) not to exceed 3.0x. As of March 31, 2025, this ratio was 0.6x; and

| • | an interest coverage ratio of consolidated EBITDDA to the sum of consolidated interest expense and consolidated lease expense (in each case as defined in the Opco Credit Facility) of not less than 3.5 to 1.0. As of March 31, 2025, this ratio was 13.6x.

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 the three months ended March 31, 2025, the Partnership borrowed $33.7 million and repaid $37.0 million, resulting in $110.4 million in borrowings outstanding under the Opco Credit Facility and $89.6 million of available borrowing capacity as of March 31, 2025. During the three months ended March 31, 2024, the Partnership borrowed $89.4 million and repaid $39.0 million on the Opco Credit Facility. The weighted average interest rate for the borrowings outstanding under the Opco Credit Facility for the three months ended March 31, 2025 and 2024 was 7.93% and 8.94%, respectively.

The Opco Credit Facility is collateralized and secured by liens on certain of Opco’s assets with carrying values of $299.4 million and $302.8 million classified as mineral rights, net and other long-term assets, net and $22.7 million and $23.5 million classified as long-term contract receivable, net on the Partnership’s Consolidated Balance Sheets as of March 31, 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 March 31, 2025, the 5.03% and 5.18% Opco Senior Notes remain outstanding. These Opco Senior Notes have principal due annually in December and interest due semi-annually in June and December. As of both March 31, 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 the three months ended March 31, 2025 and 2024, respectively. These Opco Senior Notes will be fully repaid in December 2026.

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

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:

|  |  |  |  |  | March 31, 2025 |  |  | December 31, 2024 |
|  | Fair Value |  |  | Carrying |  |  | Estimated |  |  | Carrying |  |  | Estimated |
(In thousands) |  | Hierarchy Level |  |  | Value |  |  | Fair Value |  |  | Value |  |  | Fair Value |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contract receivable, net (current and long-term) (1) |  |  | 3 |  |  | $ | 25,632 |  |  | $ | 22,286 |  |  | $ | 26,321 |  |  | $ | 22,776 |
Debt: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Opco Senior Notes (2) |  |  | 3 |  |  | $ | 28,420 |  |  | $ | 27,502 |  |  | $ | 28,384 |  |  | $ | 27,498 |
Opco Credit Facility (3) |  |  | 3 |  |  |  | 110,384 |  |  |  | 110,384 |  |  |  | 113,684 |  |  |  | 113,684 |

(1) | The fair value of the Partnership's contract receivable is determined based on the present value of future cash flow projections related to the underlying asset at a discount rate of 15% at March 31, 2025 and December 31, 2024.
(2) | The fair value of the Opco Senior Notes was estimated by management utilizing the present value replacement method incorporating the interest rate of the Opco Credit Facility.
(3) | The fair value of the Opco Credit Facility approximates the outstanding borrowing amount because the interest rates are variable and reflective of market rates and the terms of the credit facility allow the Partnership to repay the debt at any time without penalty.

11. Related Party Transactions

Affiliates of our General Partner

The Partnership’s general partner does not 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:

|  | For the Three Months Ended March 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Operating and maintenance expenses |  | $ | 1,793 |  |  | $ | 1,766 |
General and administrative expenses |  |  | 1,569 |  |  |  | 1,303 |

The Partnership had accounts payable to related parties of $0.5 million on its Consolidated Balance Sheets at March 31, 2025 and $0.6 million at 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 March 31, 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 March 31, 2025 and December 31, 2024.

During the three months ended March 31, 2025, and 2024, the Partnership recognized $0.1 million and $0.03 million in operating and maintenance expenses, respectively, on its Consolidated Statements of Comprehensive Income related to an overriding royalty agreement with WPPLP. The Partnership had $0.1 million in accounts payable on its Consolidated Balance Sheets at March 31, 2025 related to this agreement as well as $0.5 million of other long-term assets, net on its Consolidated Balance Sheets related to a prepaid royalty for this agreement at both March 31, 2025 and December 31, 2024.

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

12. Major Customers

Revenues from customers that exceeded 10 percent of total revenues for any of the periods presented below are as follows:

|  | For the Three Months Ended March 31, |
|  | 2025 |  |  | 2024 |
(In thousands) |  | Revenues |  |  | Percent |  |  | Revenues |  |  | Percent |
Alpha Metallurgical Resources, Inc. (1) |  | $ | 13,176 |  |  |  | 24 | % |  | $ | 20,902 |  |  |  | 27 | %
Foresight Energy Resources LLC ("Foresight") (1) |  | $ | 16,460 |  |  |  | 30 | % |  | $ | 12,846 |  |  |  | 17 | %

(1) | Revenues from Alpha Metallurgical Resources, Inc. and Foresight are included within the Partnership's Mineral Rights segment.

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 will not have a material effect on the Partnership’s financial position, liquidity or operations.

14. Unit-Based Compensation

During the three months ended March 31, 2025 and 2024, the Partnership granted service, performance and market-based awards under its 2017 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 three months ended March 31, 2025 and 2024 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 the three months ended March 31, 2025 and 2024. Total unit-based compensation expense associated with these awards was $2.7 million and $3.0 million for the three months ended March 31, 2025 and 2024, 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 March 31, 2025 was $13.9 million, which will be recognized over a weighted average period of 1.9 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 the three months ended March 31, 2025 and 2024, 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 during 2025 is as follows:

(In thousands) |  | Common Units |  |  | Weighted Average Grant Date Fair Value per Common Unit |
Outstanding at January 1, 2025 |  |  | 350 |  |  | $ | 60.81 |
Granted |  |  | 57 |  |  | $ | 117.98 |
Fully vested and issued |  |  | (141 | ) |  | $ | 50.33 |
Outstanding at March 31, 2025 |  |  | 266 |  |  | $ | 78.68 |

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NATURAL RESOURCE PARTNERS L.P.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—CONTINUED
(Unaudited)

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 are not 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 March 31, 2025 and December 31, 2024, NRP had the following current expected credit loss (“CECL”) allowance related to its receivables and long-term contract receivable:

|  | March 31, 2025 |  |  | December 31, 2024 |
(In thousands) |  | Gross |  |  | CECL Allowance |  |  | Net |  |  | Gross |  |  | CECL Allowance |  |  | Net |
Receivables |  | $ | 36,438 |  |  | $ | (4,171 | ) |  | $ | 32,267 |  |  | $ | 37,270 |  |  | $ | (4,425 | ) |  | $ | 32,845 |
Long-term contract receivable |  |  | 23,550 |  |  |  | (816 | ) |  |  | 22,734 |  |  |  | 24,323 |  |  |  | (843 | ) |  |  | 23,480 |
Total |  | $ | 59,988 |  |  | $ | (4,987 | ) |  | $ | 55,001 |  |  | $ | 61,593 |  |  | $ | (5,268 | ) |  | $ | 56,325 |

NRP recorded reversals of $0.3 million and $0.8 million of operating and maintenance expenses on its Consolidated Statements of Comprehensive Income related to the change in the CECL allowance during the three months ended March 31, 2025 and 2024, 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 March 31, 2025 through the time of the Partnership’s filing of its Quarterly Report on Form 10-Q with the SEC:

Common Unit Distributions

In May 2025, the Board of Directors declared a distribution of $0.75 per common unit with respect to the first quarter of 2025.

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ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following review of operations for the three month periods ended March 31, 2025 and 2024 should be read in conjunction with our Consolidated Financial Statements and the Notes to Consolidated Financial Statements included in this Form 10-Q and with the Consolidated Financial Statements, Notes to Consolidated Financial Statements and Management’s Discussion and Analysis included in the Natural Resource Partners L.P. Annual Report on Form 10-K for the year ended December 31, 2024.

As used herein, unless the context otherwise requires: "we," "our," "us" and the "Partnership" refer to Natural Resource Partners L.P. and, where the context requires, our subsidiaries. References to "NRP" and "Natural Resource Partners" refer to Natural Resource Partners L.P. only, and not to NRP (Operating) LLC or any of Natural Resource Partners L.P.’s subsidiaries. References to "Opco" refer to NRP (Operating) LLC, a wholly owned subsidiary of NRP, and its subsidiaries.

INFORMATION REGARDING FORWARD-LOOKING STATEMENTS

Statements included in this 10-Q may constitute forward-looking statements. In addition, we and our representatives may from time to time make other oral or written statements which are also forward-looking statements. Such forward-looking statements include, among other things, statements regarding: future distributions on our common units; our business strategy; our liquidity and access to capital and financing sources; our financial strategy; prices of and demand for coal, trona and soda ash, and other natural resources; estimated revenues, expenses and results of operations; projected future performance by our lessees; Sisecam Wyoming LLC’s ("Sisecam Wyoming's") trona mining and soda ash refinery operations; distributions from our soda ash joint venture; the impact of governmental policies, laws and regulations, as well as regulatory and legal proceedings involving us, and of scheduled or potential regulatory or legal changes; and global and U.S. economic conditions.

These forward-looking statements speak only as of the date hereof and are made based upon our current plans, expectations, estimates, assumptions and beliefs concerning future events impacting us and involve a number of risks and uncertainties. We caution that forward-looking statements are not guarantees and that actual results could differ materially from those expressed or implied in the forward-looking statements. You should not put undue reliance on any forward-looking statements. See "Item 1A. Risk Factors" included in this Form 10-Q and in our Annual Report on Form 10-K for the year ended December 31, 2024 for important factors that could cause our actual results of operations or our actual financial condition to differ.

NON-GAAP FINANCIAL MEASURES

Adjusted EBITDA

Adjusted EBITDA is a non-GAAP financial measure that we define as net income (loss) less equity earnings from unconsolidated investment; plus total distributions from unconsolidated investment, interest expense, net, debt modification expense, loss on extinguishment of debt, depreciation, depletion and amortization and asset impairments. Adjusted EBITDA should not be considered an alternative to, or more meaningful than, net income or loss, net income or loss attributable to partners, operating income or loss, cash flows from operating activities or any other measure of financial performance presented in accordance with GAAP as measures of operating performance, liquidity or ability to service debt obligations. There are significant limitations to using Adjusted EBITDA as a measure of performance, including the inability to analyze the effect of certain recurring items that materially affect our net income, the lack of comparability of results of operations of different companies and the different methods of calculating Adjusted EBITDA reported by different companies. In addition, Adjusted EBITDA presented below is not calculated or presented on the same basis as Consolidated EBITDA as defined in our partnership agreement or Consolidated EBITDDA as defined in Opco's debt agreements. For a description of Opco's debt agreements, see Note 9. Debt, Net in the Notes to Consolidated Financial Statements included herein as well as in "Item 8. Financial Statements and Supplementary Data—Note 11. Debt, Net" in our Annual Report on Form 10-K for the year ended December 31, 2024. Adjusted EBITDA is a supplemental performance measure used by our management and by external users of our financial statements, such as investors, commercial banks, research analysts and others to assess the financial performance of our assets without regard to financing methods, capital structure or historical cost basis.

Distributable Cash Flow

Distributable cash flow ("DCF") represents net cash provided by (used in) operating activities plus distributions from unconsolidated investment in excess of cumulative earnings, proceeds from asset sales and disposals, including sales of discontinued operations, and return of long-term contract receivable; less maintenance capital expenditures. DCF is not a measure of financial performance under GAAP and should not be considered as an alternative to cash flows from operating, investing or financing activities. DCF may not be calculated the same for us as for other companies. In addition, DCF presented below is not calculated or presented on the same basis as distributable cash flow as defined in our partnership agreement, which is used as a metric to determine whether we are able to increase quarterly distributions to our common unitholders. DCF is a supplemental liquidity measure used by our management and by external users of our financial statements, such as investors, commercial banks, research analysts and others to assess our ability to make cash distributions and repay debt.

Free Cash Flow

Free cash flow ("FCF") represents net cash provided by (used in) operating activities plus distributions from unconsolidated investment in excess of cumulative earnings and return of long-term contract receivable; less maintenance and expansion capital expenditures and cash flow used in acquisition costs classified as investing or financing activities. FCF is calculated before mandatory debt repayments. FCF is not a measure of financial performance under GAAP and should not be considered as an alternative to cash flows from operating, investing or financing activities. FCF may not be calculated the same for us as for other companies. FCF is a supplemental liquidity measure used by our management and by external users of our financial statements, such as investors, commercial banks, research analysts and others to assess our ability to make cash distributions and repay debt.

Leverage Ratio

Leverage ratio represents the outstanding principal of our debt at the end of the period divided by the last twelve months' Adjusted EBITDA as defined above. We believe that leverage ratio is a useful measure to management and investors to evaluate and monitor our indebtedness relative to our ability to generate income to service such debt and in understanding trends in our overall financial condition. Leverage ratio may not be calculated the same for us as for other companies and is not a substitute for, and should not be used in conjunction with, GAAP financial ratios.

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Introduction

The following discussion and analysis presents management's view of our business, financial condition and overall performance. Our discussion and analysis consists of the following subjects:

• Executive Overview

• Results of Operations

• Liquidity and Capital Resources

• Off-Balance Sheet Transactions

• Related Party Transactions

• Summary of Critical Accounting Estimates

• Recent Accounting Standards

Executive Overview

We are a diversified natural resource company engaged 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 own a non-controlling 49% interest in Sisecam Wyoming, a trona ore mining and soda ash production business. Our common units trade on the New York Stock Exchange under the symbol "NRP." Our business is organized into two operating segments:

Mineral Rights—consists of approximately 13 million acres of mineral interests and other subsurface rights across the United States. If combined in a single tract, our ownership would cover roughly 20,000 square miles, including 3.5 million acres of underground pore space for the sequestration of carbon dioxide. Our assets provides critical inputs for the manufacturing of steel, electricity building materials, and components used in the generation of renewable energy.

Soda Ash—consists of our 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 our partner, Sisecam Chemicals Wyoming LLC, and we realize cash flow when distributions are paid to us.

Corporate and Financing includes functional corporate departments that do not earn revenues. Costs incurred by these departments include interest and financing, corporate headquarters and overhead, centralized treasury, legal and accounting and other corporate-level activity not specifically allocated to a segment.

Our financial results by segment for the three months ended March 31, 2025 are as follows:

|  | Operating Segments |  |  |  |  |  |  |  |  |
(In thousands) |  | Mineral Rights |  |  | Soda Ash |  |  | Corporate and Financing |  |  | Total |
Revenues and other income |  | $ | 55,928 |  |  | $ | 4,610 |  |  | $ | — |  |  | $ | 60,538 |
Net income (loss) |  | $ | 45,208 |  |  | $ | 4,550 |  |  | $ | (9,505 | ) |  | $ | 40,253 |
Adjusted EBITDA (1) |  | $ | 49,213 |  |  | $ | 2,880 |  |  | $ | (6,833 | ) |  | $ | 45,260 |
Cash flow provided by (used in) continuing operations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating activities |  | $ | 43,223 |  |  | $ | 2,880 |  |  | $ | (11,679 | ) |  | $ | 34,424 |
Investing activities |  | $ | 947 |  |  | $ | — |  |  | $ | — |  |  | $ | 947 |
Financing activities |  | $ | (841 | ) |  | $ | — |  |  | $ | (34,098 | ) |  | $ | (34,939 | )
Distributable cash flow (1) |  | $ | 44,170 |  |  | $ | 2,880 |  |  | $ | (11,679 | ) |  | $ | 35,371 |
Free cash flow (1) |  | $ | 43,923 |  |  | $ | 2,880 |  |  | $ | (11,679 | ) |  | $ | 35,124 |

(1) | See "Results of Operations" below for reconciliations to the most comparable GAAP financial measures.

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Current Results/Market Commentary

Financial Results and Quarterly Distributions

We generated $34.4 million of operating cash flow and $35.1 million of free cash flow during the three months ended March 31, 2025, and ended the quarter with $120.5 million of liquidity consisting of $30.9 million of cash and cash equivalents and $89.6 million of available borrowing capacity under our Opco Credit Facility. As of March 31, 2025 our leverage ratio was 0.7 x.

In February 2025, we paid a cash distribution of $0.75 per common unit of NRP with respect to the fourth quarter of 2024. In March 2025, we paid a special cash distribution of $1.21 per common unit of NRP to help cover unitholder tax liabilities associated with owning NRP's common units in 2024. Future distributions on our common units will be determined on a quarterly basis by the Board of Directors. The Board of Directors considers numerous factors each quarter in determining cash distributions, including profitability, cash flow, debt service obligations, market conditions and outlook, estimated unitholder income tax liability and the level of cash reserves that the Board of Directors determines is necessary for future operating and capital needs.

Mineral Rights Business Segment

Revenues and other income during the three months ended March 31, 2025 decreased $15.0 million, or 21%, as compared to the prior year period. Cash provided by operating activities and free cash flow during the three months ended March 31, 2025 each decreased by $26.5 million, as compared to the prior year period. These decreases were primarily due to lower metallurgical coal sales prices and volumes as compared to the prior year period.

We expect pricing in 2025 to remain muted for both metallurgical and thermal coal as soft global steel demand impacts metallurgical coal and domestic thermal coal inventory levels at power plants, while declining, remain well above their historical 5-year average. Despite this weakened and uncertain environment, we expect continued price support above the historically normal price levels due to elevated input cost inflation, operators' limited access to capital, and qualified labor shortages.

We continue to explore carbon neutral revenue opportunities across our mineral and surface assets for the sequestration of carbon dioxide underground and in standing forests, lithium production, and the generation of electricity using geothermal, solar, and wind energy. While the timing and likelihood of additional cash flows from these activities is uncertain, we believe our vast ownership footprint throughout the United States provides additional opportunities to create value in this regard with minimal capital investment by us.

Soda Ash Business Segment

Revenues and other income during the three months ended March 31, 2025 decreased $0.8 million, or 15%, as compared to the prior year period primarily due to increased international sales mix in 2025.

Cash provided by operating activities and free cash flow during the three months ended March 31, 2025 each decreased $11.3 million as compared to the prior year period due to a lower cash distribution received from Sisecam Wyoming in the first quarter of 2025.

The soda ash market continues to be impacted by significant recent increases in global capacity introduced in 2024, primarily from China, as well as weakening demand for flat glass due to slower growth in global construction activity and lower demand for automobiles. International soda ash prices remain at or below the cost of production for many operators. We believe this weak pricing environment will continue throughout 2025 and into 2026 unless there is a significant rightsizing of high-cost producers shutting down out-of-the-money production or a significant rebound in the demand for flat glass. As such, we expect distributions from Sisecam Wyoming to remain at lower levels for the foreseeable future.

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Results of Operations

First Quarter of 2025 and 2024 Compared

Revenues and Other Income

The following table includes our revenues and other income by operating segment:

|  | For the Three Months Ended March 31, |  |  |  |  | Percentage |
Operating Segment (In thousands) |  | 2025 |  |  | 2024 |  |  | Decrease |  |  | Change |
Mineral Rights |  | $ | 55,928 |  |  | $ | 70,964 |  |  | $ | (15,036 | ) |  |  | (21 | )%
Soda Ash |  |  | 4,610 |  |  |  | 5,450 |  |  |  | (840 | ) |  |  | (15 | )%
Total |  | $ | 60,538 |  |  | $ | 76,414 |  |  | $ | (15,876 | ) |  |  | (21 | )%

The changes in revenues and other income are discussed for each of the operating segments below:

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Mineral Rights

The following table presents coal sales volumes, coal royalty revenue per ton and coal royalty revenues by major coal producing region, the significant categories of other revenues and other income:

|  | For the Three Months Ended March 31, |  |  | Increase |  |  | Percentage |
(In thousands, except per ton data) |  | 2025 |  |  | 2024 |  |  | (Decrease) |  |  | Change |
Coal sales volumes (tons) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Appalachia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Northern |  |  | 124 |  |  |  | 117 |  |  |  | 7 |  |  |  | 6 | %
Central |  |  | 3,306 |  |  |  | 3,714 |  |  |  | (408 | ) |  |  | (11 | )%
Southern |  |  | 296 |  |  |  | 570 |  |  |  | (274 | ) |  |  | (48 | )%
Total Appalachia |  |  | 3,726 |  |  |  | 4,401 |  |  |  | (675 | ) |  |  | (15 | )%
Illinois Basin |  |  | 3,342 |  |  |  | 2,033 |  |  |  | 1,309 |  |  |  | 64 | %
Northern Powder River Basin |  |  | 916 |  |  |  | 949 |  |  |  | (33 | ) |  |  | (3 | )%
Gulf Coast |  |  | 237 |  |  |  | 265 |  |  |  | (28 | ) |  |  | (11 | )%
Total coal sales volumes |  |  | 8,221 |  |  |  | 7,648 |  |  |  | 573 |  |  |  | 7 | %
Coal royalty revenue per ton |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Appalachia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Northern |  | $ | 1.48 |  |  | $ | 1.86 |  |  | $ | (0.38 | ) |  |  | (20 | )%
Central |  |  | 6.18 |  |  |  | 8.08 |  |  |  | (1.90 | ) |  |  | (24 | )%
Southern |  |  | 9.18 |  |  |  | 11.58 |  |  |  | (2.40 | ) |  |  | (21 | )%
Illinois Basin |  |  | 2.44 |  |  |  | 2.56 |  |  |  | (0.12 | ) |  |  | (5 | )%
Northern Powder River Basin |  |  | 4.55 |  |  |  | 4.85 |  |  |  | (0.30 | ) |  |  | (6 | )%
Gulf Coast |  |  | 0.78 |  |  |  | 0.75 |  |  |  | 0.03 |  |  |  | 4 | %
Combined average coal royalty revenue per ton |  |  | 4.36 |  |  |  | 6.12 |  |  |  | (1.76 | ) |  |  | (29 | )%
Coal royalty revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Appalachia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Northern |  | $ | 183 |  |  | $ | 218 |  |  | $ | (35 | ) |  |  | (16 | )%
Central |  |  | 20,426 |  |  |  | 29,992 |  |  |  | (9,566 | ) |  |  | (32 | )%
Southern |  |  | 2,718 |  |  |  | 6,602 |  |  |  | (3,884 | ) |  |  | (59 | )%
Total Appalachia |  |  | 23,327 |  |  |  | 36,812 |  |  |  | (13,485 | ) |  |  | (37 | )%
Illinois Basin |  |  | 8,141 |  |  |  | 5,211 |  |  |  | 2,930 |  |  |  | 56 | %
Northern Powder River Basin |  |  | 4,169 |  |  |  | 4,599 |  |  |  | (430 | ) |  |  | (9 | )%
Gulf Coast |  |  | 184 |  |  |  | 200 |  |  |  | (16 | ) |  |  | (8 | )%
Unadjusted coal royalty revenues |  |  | 35,821 |  |  |  | 46,822 |  |  |  | (11,001 | ) |  |  | (23 | )%
Coal royalty adjustment for minimum leases |  |  | (323 | ) |  |  | (4 | ) |  |  | (319 | ) |  |  | (7975 | )%
Total coal royalty revenues |  | $ | 35,498 |  |  | $ | 46,818 |  |  | $ | (11,320 | ) |  |  | (24 | )%
Other revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Production lease minimum revenues |  | $ | 2,725 |  |  | $ | 924 |  |  | $ | 1,801 |  |  |  | 195 | %
Minimum lease straight-line revenues |  |  | 4,050 |  |  |  | 4,171 |  |  |  | (121 | ) |  |  | (3 | )%
Oil and gas royalty revenues |  |  | 2,444 |  |  |  | 3,640 |  |  |  | (1,196 | ) |  |  | (33 | )%
Carbon neutral revenues |  |  | 595 |  |  |  | 2,161 |  |  |  | (1,566 | ) |  |  | (72 | )%
Property tax revenues |  |  | 1,637 |  |  |  | 1,892 |  |  |  | (255 | ) |  |  | (13 | )%
Wheelage revenues |  |  | 1,738 |  |  |  | 2,672 |  |  |  | (934 | ) |  |  | (35 | )%
Coal overriding royalty revenues |  |  | 880 |  |  |  | 1,169 |  |  |  | (289 | ) |  |  | (25 | )%
Lease amendment revenues |  |  | 655 |  |  |  | 702 |  |  |  | (47 | ) |  |  | (7 | )%
Aggregates royalty revenues |  |  | 853 |  |  |  | 772 |  |  |  | 81 |  |  |  | 10 | %
Other revenues |  |  | 185 |  |  |  | 2,451 |  |  |  | (2,266 | ) |  |  | (92 | )%
Total other revenues |  | $ | 15,762 |  |  | $ | 20,554 |  |  | $ | (4,792 | ) |  |  | (23 | )%
Royalty and other mineral rights |  | $ | 51,260 |  |  | $ | 67,372 |  |  | $ | (16,112 | ) |  |  | (24 | )%
Transportation and processing services revenues |  |  | 4,421 |  |  |  | 3,427 |  |  |  | 994 |  |  |  | 29 | %
Gain on asset sales and disposals |  |  | 247 |  |  |  | 165 |  |  |  | 82 |  |  |  | 50 | %
Total Mineral Rights segment revenues and other income |  | $ | 55,928 |  |  | $ | 70,964 |  |  | $ | (15,036 | ) |  |  | (21 | )%

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Coal Royalty Revenues

Approximately 55% of coal royalty revenues and approximately 40% of coal royalty sales volumes were derived from metallurgical coal during the three months ended March 31, 2025. Total coal royalty revenues decreased $11.3 million as compared to the prior year quarter primarily due to lower metallurgical coal sales prices and volumes during the three months ended March 31, 2025, as compared to the prior year quarter.

Other Revenues

Other revenues decreased $4.8 million primarily as a result of a $2.3 million decrease in other revenues, a $1.6 million decrease in carbon neutral revenues and a $1.2 million decrease in oil and gas royalty revenues.

Soda Ash

Revenues and other income related to our Soda Ash segment decreased $0.8 million as compared to the prior year quarter primarily due to increased international sales mix in 2025.

Adjusted EBITDA (Non-GAAP Financial Measure)

The following table reconciles net income (loss) (the most comparable GAAP financial measure) to Adjusted EBITDA by business segment:

|  | Operating Segments |  |  |  |  |  |  |  |  |
For the Three Months Ended (In thousands) |  | Mineral Rights |  |  | Soda Ash |  |  | Corporate and Financing |  |  | Total |
March 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  | $ | 45,208 |  |  | $ | 4,550 |  |  | $ | (9,505 | ) |  | $ | 40,253 |
Less: equity earnings from unconsolidated investment |  |  | — |  |  |  | (4,610 | ) |  |  | — |  |  |  | (4,610 | )
Add: total distributions from unconsolidated investment |  |  | — |  |  |  | 2,940 |  |  |  | — |  |  |  | 2,940 |
Add: interest expense, net |  |  | — |  |  |  | — |  |  |  | 2,668 |  |  |  | 2,668 |
Add: depreciation, depletion and amortization |  |  | 3,985 |  |  |  | — |  |  |  | 4 |  |  |  | 3,989 |
Add: asset impairments |  |  | 20 |  |  |  | — |  |  |  | — |  |  |  | 20 |
Adjusted EBITDA |  | $ | 49,213 |  |  | $ | 2,880 |  |  | $ | (6,833 | ) |  | $ | 45,260 |
March 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  | $ | 60,644 |  |  | $ | 5,388 |  |  | $ | (9,819 | ) |  | $ | 56,213 |
Less: equity earnings from unconsolidated investment |  |  | — |  |  |  | (5,450 | ) |  |  | — |  |  |  | (5,450 | )
Add: total distributions from unconsolidated investment |  |  | — |  |  |  | 14,210 |  |  |  | — |  |  |  | 14,210 |
Add: interest expense, net |  |  | — |  |  |  | — |  |  |  | 3,487 |  |  |  | 3,487 |
Add: depreciation, depletion and amortization |  |  | 4,649 |  |  |  | — |  |  |  | 5 |  |  |  | 4,654 |
Adjusted EBITDA |  | $ | 65,293 |  |  | $ | 14,148 |  |  | $ | (6,327 | ) |  | $ | 73,114 |

Net income decreased $16.0 million as compared to the prior year quarter primarily due to the decrease in revenues and other income as discussed above. Adjusted EBITDA decreased $27.9 million as compared to the prior year quarter primarily due to an $16.1 million decrease in Adjusted EBITDA within our Mineral Rights segment driven by the lower revenues and other income as discussed above in addition to an $11.3 million decrease in Adjusted EBITDA within our Soda Ash segment driven by a lower cash distribution received from Sisecam Wyoming in the first quarter of 2025.

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Distributable Cash Flow ("DCF") and Free Cash Flow ("FCF") (Non-GAAP Financial Measures)

The following table presents the three major categories of the statement of cash flows by business segment:

|  | Operating Segments |  |  |  |  |  |  |  |  |
For the Three Months Ended (In thousands) |  | Mineral Rights |  |  | Soda Ash |  |  | Corporate and Financing |  |  | Total |
March 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash flow provided by (used in) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating activities |  | $ | 43,223 |  |  | $ | 2,880 |  |  | $ | (11,679 | ) |  | $ | 34,424 |
Investing activities |  |  | 947 |  |  |  | — |  |  |  | — |  |  |  | 947 |
Financing activities |  |  | (841 | ) |  |  | — |  |  |  | (34,098 | ) |  |  | (34,939 | )
March 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash flow provided by (used in) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating activities |  | $ | 69,749 |  |  | $ | 14,148 |  |  | $ | (12,398 | ) |  | $ | 71,499 |
Investing activities |  |  | 812 |  |  |  | — |  |  |  | — |  |  |  | 812 |
Financing activities |  |  | (1,086 | ) |  |  | — |  |  |  | (72,224 | ) |  |  | (73,310 | )

The following table reconciles net cash provided by (used in) operating activities (the most comparable GAAP financial measure) by business segment to DCF and FCF:

|  | Operating Segments |  |  |  |  |  |  |  |  |
For the Three Months Ended (In thousands) |  | Mineral Rights |  |  | Soda Ash |  |  | Corporate and Financing |  |  | Total |
March 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net cash provided by (used in) operating activities |  | $ | 43,223 |  |  | $ | 2,880 |  |  | $ | (11,679 | ) |  | $ | 34,424 |
Add: proceeds from asset sales and disposals |  |  | 247 |  |  |  | — |  |  |  | — |  |  |  | 247 |
Add: return of long-term contract receivable |  |  | 700 |  |  |  | — |  |  |  | — |  |  |  | 700 |
Distributable cash flow |  | $ | 44,170 |  |  | $ | 2,880 |  |  | $ | (11,679 | ) |  | $ | 35,371 |
Less: proceeds from asset sales and disposals |  |  | (247 | ) |  |  | — |  |  |  | — |  |  |  | (247 | )
Free cash flow |  | $ | 43,923 |  |  | $ | 2,880 |  |  | $ | (11,679 | ) |  | $ | 35,124 |
March 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net cash provided by (used in) operating activities |  | $ | 69,749 |  |  | $ | 14,148 |  |  | $ | (12,398 | ) |  | $ | 71,499 |
Add: proceeds from asset sales and disposals |  |  | 165 |  |  |  | — |  |  |  | — |  |  |  | 165 |
Add: return of long-term contract receivable |  |  | 647 |  |  |  | — |  |  |  | — |  |  |  | 647 |
Distributable cash flow |  | $ | 70,561 |  |  | $ | 14,148 |  |  | $ | (12,398 | ) |  | $ | 72,311 |
Less: proceeds from asset sales and disposals |  |  | (165 | ) |  |  | — |  |  |  | — |  |  |  | (165 | )
Free cash flow |  | $ | 70,396 |  |  | $ | 14,148 |  |  | $ | (12,398 | ) |  | $ | 72,146 |

Operating cash flow, DCF and FCF decreased $37.1 million, $36.9 million and $37.0 million, respectively, as compared to the prior year quarter. The discussion by segment is as follows:

| • | Mineral Rights Segment

| ◦ | Operating cash flow, DCF and FCF decreased $26.5 million, $26.4 million and $26.5 million, respectively, primarily due to lower metallurgical coal sales prices and volumes as compared to the prior year quarter.

| • | Soda Ash Segment

| ◦ | Operating cash flow, DCF and FCF each decreased $11.3 million as compared to the prior year quarter primarily due to a lower cash distribution received from Sisecam Wyoming in the first quarter of 2025.

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Liquidity and Capital Resources

Current Liquidity

As of March 31, 2025, we had total liquidity of $120.5 million, consisting of $30.9 million of cash and cash equivalents and $89.6 million of borrowing capacity under our Opco Credit Facility. We have debt service obligations, including $14.3 million of principal repayments on Opco’s senior notes, throughout the remainder of 2025. The following table calculates our leverage ratio as of March 31, 2025:

|  | For the Three Months Ended |  |  |  |  |
(In thousands) |  | June 30, 2024 |  |  | September 30, 2024 |  |  | December 31, 2024 |  |  | March 31, 2025 |  |  | Last 12 Months |
Net income |  | $ | 46,064 |  |  | $ | 38,595 |  |  | $ | 42,772 |  |  | $ | 40,253 |  |  | $ | 167,684 |
Less: equity earnings from unconsolidated investment |  |  | (3,645 | ) |  |  | (8,109 | ) |  |  | (931 | ) |  |  | (4,610 | ) |  |  | (17,295 | )
Add: total distributions from unconsolidated investment |  |  | 7,584 |  |  |  | 6,320 |  |  |  | 10,667 |  |  |  | 2,940 |  |  |  | 27,511 |
Add: interest expense, net |  |  | 4,349 |  |  |  | 4,194 |  |  |  | 3,524 |  |  |  | 2,668 |  |  |  | 14,735 |
Add: depreciation, depletion and amortization |  |  | 3,324 |  |  |  | 4,730 |  |  |  | 2,827 |  |  |  | 3,989 |  |  |  | 14,870 |
Add: asset impairments |  |  | — |  |  |  | 87 |  |  |  | — |  |  |  | 20 |  |  |  | 107 |
Adjusted EBITDA |  | $ | 57,676 |  |  | $ | 45,817 |  |  | $ | 58,859 |  |  | $ | 45,260 |  |  | $ | 207,612 |
Debt—at March 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ | 139,047 |
Leverage Ratio |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.7 x |

Cash Flows

Cash flows provided by operating activities decreased $37.1 million, from $71.5 million in the three months ended March 31, 2024 to $34.4 million in the three months ended March 31, 2025, primarily due to decreased cash flow within our Mineral Rights and Soda Ash segments, all discussed above.

Cash used in financing activities decreased $38.4 million, from $73.3 million used in the three months ended March 31, 2024 to $34.9 million used in the three months ended March 31, 2025 due to the following:

| • | $55.7 million of cash used for the warrant settlements during the three months ended March 31, 2024;
| • | $18.7 million of decreased debt repayments in 2025 as compared to 2024;
| • | $15.9 million of decreased common unit distributions primarily as a result of a lower special distribution paid during the three months ended March 31, 2025 as compared to the prior year period;
| • | $2.2 million of cash used for preferred unit distributions during the three months ended March 31, 2024; and
| • | $1.6 million of decreased cash used for other items, net in 2025 as compared to 2024.

These decreases in cash flow used were partially offset by $55.7 million in decreased debt borrowings during the three months ended March 31, 2025 as compared to the prior year period.

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Capital Resources and Obligations

Debt, Net

We had the following debt outstanding as of March 31, 2025 and December 31, 2024:

|  | March 31, |  |  | December 31, |
(In thousands) |  | 2025 |  |  | 2024 |
Current portion of long-term debt, net |  | $ | 14,210 |  |  | $ | 14,192 |
Long-term debt, net |  |  | 124,594 |  |  |  | 127,876 |
Total debt, net |  | $ | 138,804 |  |  | $ | 142,068 |

We have been and continue to be in compliance with the terms of the financial covenants contained in our debt agreements. For additional information regarding our debt and the agreements governing our debt, including the covenants contained therein, see Note 9. Debt, Net to the Consolidated Financial Statements included elsewhere in this Quarterly Report on Form 10-Q.

Off-Balance Sheet Transactions

We do not have any off-balance sheet arrangements with unconsolidated entities or related parties and accordingly, there are no off-balance sheet risks to our liquidity and capital resources from unconsolidated entities.

Related Party Transactions

The information required set forth under Note 11. Related Party Transactions to the Consolidated Financial Statements is incorporated herein by reference.

Summary of Critical Accounting Estimates

The preparation of Consolidated Financial Statements in conformity with generally accepted accounting principles in the United States of America requires management to make certain estimates and assumptions that affect the amounts reported in the Consolidated Financial Statements and the accompanying notes. There have been no significant changes to our critical accounting estimates from those disclosed in our Annual Report on Form 10-K for the year ended December 31, 2024.

Recently Issued Accounting Standard

In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures ("ASU 2024-03"). ASU 2024-03 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, 2026 and quarterly periods beginning after December 31, 2027 and 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. We do not expect the adoption of this guidance to have a material impact on our Consolidated Financial Statements.

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ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

We are exposed to market risk, which includes adverse changes in commodity prices and interest rates as discussed below:

Commodity Price Risk

Our revenues, operating results, financial condition and ability to borrow funds or obtain additional capital depend substantially on prevailing commodity prices. Historically, coal prices have been volatile, with prices fluctuating widely, and are likely to continue to be volatile. Depressed prices in the future would have a negative impact on our future financial results. In particular, substantially lower prices would significantly reduce revenues and could potentially trigger an impairment of our coal properties or a violation of certain financial debt covenants. Because substantially all our reserves are coal, changes in coal prices have a more significant impact on our financial results.

We are dependent upon the effective marketing of the coal mined by our lessees. Our lessees sell the coal under various long-term and short-term contracts as well as on the spot market. Current conditions in the coal industry may make it difficult for our lessees to extend existing contracts or enter into supply contracts with terms of one year or more. Our lessees' failure to negotiate long-term contracts could adversely affect the stability and profitability of our lessees' operations and adversely affect our future financial results. If more coal is sold on the spot market, coal royalty revenues may become more volatile due to fluctuations in spot coal prices.

The market price of soda ash and energy costs directly affects the profitability of Sisecam Wyoming's operations. If the market price for soda ash declines, Sisecam Wyoming's sales revenues will decrease. Historically, the global market and, to a lesser extent, the domestic market for soda ash have been volatile and are likely to remain volatile in the future.

Interest Rate Risk

Our exposure to changes in interest rates results from our borrowings under the Opco Credit Facility, which is subject to variably interest rates based upon SOFR. At March 31, 2025, we had $110.4 million in borrowings outstanding under the Opco Credit Facility. If interest rates were to increase by 1%, annual interest expense would increase approximately $1.1 million, assuming the same principal amount remained outstanding during the year.

ITEM 4. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

NRP carried out an evaluation of the effectiveness of the design and operation of its disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) as of the end of the period covered by this report. This evaluation was performed under the supervision and with the participation of NRP management, including the Chief Executive Officer and Chief Financial Officer of the general partner of the general partner of NRP. Based upon that evaluation, the Chief Executive Officer and Chief Financial Officer concluded that these disclosure controls and procedures are effective in providing reasonable assurance that (a) the information required to be disclosed by us in the reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Securities and Exchange Commission’s rules and forms, and (b) such information is accumulated and communicated to our management, including our CEO and CFO, as appropriate to allow timely decisions regarding required disclosure.

Changes in the Partnership’s Internal Control Over Financial Reporting

There were no material changes in the Partnership’s internal control over financial reporting during the first three months of 2025 that materially affected, or were reasonably likely to materially affect, the Partnership’s internal control over financial reporting.

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PART II

ITEM 1. LEGAL PROCEEDINGS

From time to time, we are involved in various legal proceedings arising in the ordinary course of business. While the ultimate results of these proceedings cannot be predicted with certainty, we believe these ordinary course matters will not have a material effect on our financial position, liquidity or operations.

ITEM 1A. RISK FACTORS

During the period covered by this report, there were no material changes from the risk factors previously disclosed in Natural Resource Partners L.P.’s Annual Report on Form 10-K for the year ended December 31, 2024.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

None.

ITEM 3. DEFAULTS UPON SENIOR SECURITIES

None.

ITEM 4. MINE SAFETY DISCLOSURES

None.

ITEM 5. OTHER INFORMATION

None.

ITEM 6. EXHIBITS

Exhibit Number |  | Description
3.1 |  | Fifth Amended and Restated Agreement of Limited Partnership of Natural Resource Partners L.P., dated as of March 2, 2017 (incorporated by reference to Exhibit 3.1 to Current Report on Form 8-K filed on March 6, 2017).
3.2 |  | Fifth Amended and Restated Agreement of Limited Partnership of NRP (GP) LP, dated as of December 16, 2011 (incorporated by reference to Exhibit 3.1 to Current Report on Form 8-K filed on December 16, 2011).
3.3 |  | Fifth Amended and Restated Limited Liability Company Agreement of GP Natural Resource Partners LLC, dated as of October 31, 2013 (incorporated by reference to Exhibit 3.1 to Current Report on Form 8-K filed on October 31, 2013).
3.4 |  | Certificate of Limited Partnership of Natural Resource Partners L.P. (incorporated by reference to Exhibit 3.1 to the Registration Statement on Form S-1 filed April 19, 2002, File No. 333-86582).
31.1* |  | Certification of Chief Executive Officer pursuant to Section 302 of Sarbanes-Oxley.
31.2* |  | Certification of Chief Financial Officer pursuant to Section 302 of Sarbanes-Oxley.
32.1** |  | Certification of Chief Executive Officer pursuant to 18 U.S.C. § 1350.
32.2** |  | Certification of Chief Financial Officer pursuant to 18 U.S.C. § 1350.
101.INS* |  | Inline XBRL Instance Document
101.SCH* |  | Inline XBRL Taxonomy Extension Schema Document
101.CAL* |  | Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF* |  | Inline XBRL Taxonomy Extension Definition Linkbase Document
101.LAB* |  | Inline XBRL Taxonomy Extension Labels Linkbase Document
101.PRE* |  | Inline XBRL Taxonomy Extension Presentation Linkbase Document
104* |  | Cover Page Interactive Data File (formatted as inline XBRL with applicable taxonomy extension information contained in Exhibits 101)
* |  | Filed herewith
** |  | Furnished herewith

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned and thereunto duly authorized.

| NATURAL RESOURCE PARTNERS L.P.
| By: | NRP (GP) LP, its general partner
| By: | GP NATURAL RESOURCE
|  | PARTNERS LLC, its general partner
Date: May 6, 2025 | By: | /s/ Corbin J. Robertson, Jr.
|  | Corbin J. Robertson, Jr.
|  | Chairman of the Board and
|  | Chief Executive Officer
|  | (Principal Executive Officer)

Date: May 6, 2025 | By: | /s/ Christopher J. Zolas
|  | Christopher J. Zolas
|  | Chief Financial Officer
|  | (Principal Financial and Accounting Officer)

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