2020 Accomplishments Zero safety incidents Generated $89 million of Free Cash Flow Reduced outstanding debt Ended the year with by $46 million $200 million of liquidity, consisting of $100 million of cash and $100 million of available borrowing capacity Reached a favorable Paid $16.6 million of agreement with Foresight distributions to common Energy, our largest lessee, unitholders which allowed them to emerge from bankruptcy and resulted in $49 million of cash to NRP in 2020 and will result in $42 million in 2021 47218natD1R3.indd 4-6 4/27/21 3:37 PM Natural Resource Partners L.P. 2020 Annual Report To Our Unitholders The unprecedented public health and economic challenges of 2020 demonstrated that we have the right strategy in place to create unitholder value. While COVID-19 ravaged the world, our partnership continued to operate safely, generate free cash flow, pay down debt, and build liquidity. All of this was accomplished while working remotely as part of our plan to prioritize the health and safety of our people. Business Highlights Our Coal Royalty & Other segment generated $126 million of Free Cash Flow in 2020. Our metallurgical properties, which are a source of coal used to manufacture steel, generated approximately 70% of our coal royalty revenues. Our Soda Ash segment consists of a 49% equity investment in Ciner Wyoming, one of the lowest cost producers of natural soda ash in the world. Global demand for soda ash, which is a key commodity used in the production of glass, was negatively impacted by the COVID-19 pandemic, causing Ciner to suspend cash distributions early in the year. As a result, we received only $14 million of Free Cash Flow from Soda Ash in 2020. While we do not know when regular distributions will recommence, the rebound in global economic activity and resulting increase in soda ash demand allowed Ciner Wyoming to resume pre-pandemic levels of production by year end. 1 47218natD2R1.indd 1 4/22/21 10:56 AM Looking Ahead In addition to actively managing our legacy business segments, we have also been working to identify alternative revenue sources across our large portfolio of land, mineral and timber assets. The types of opportunities we are exploring include the sequestration of CO2 underground and in standing timber, and the generation of electricity using geothermal, wind and solar energy. While we do not expect these activities to generate significant cash flow in the immediate future, we believe our large ownership footprint throughout the United States will provide opportunities to create value in this regard with minimal capital investment by NRP. NRP’s demonstrated ability to continue generating free cash flow, permanently reducing our outstanding debt, and paying unitholder distributions during the COVID-19 downturn is a testament to the transformative actions taken in recent years to right-size the business. Over the last five years, NRP has paid down over $900 million of debt, paid $115 million of common unitholder distributions, and worked to solidify our capital structure and ensure strong liquidity. We remain steadfast in our commitment to focus on maximizing unitholder value by continuing these efforts. Thank you to our stakeholders who supported our team through the years and thank you for your continued support of NRP. Corbin J. Robertson, Jr. Craig Nunez Chairman and Chief Executive Officer President and Chief Operating Officer 2 47218natD2R1.indd 2 4/29/21 3:25 PM UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT ☒ OF 1934 For the fiscal year ended December 31, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number: 001-31465 NATURAL RESOURCE PARTNERS L.P. (Exact name of registrant as specified in its charter) Delaware 35-2164875 (State or other jurisdiction of (I.R.S. Employer incorporation or organization) Identification No.) 1201 Louisiana Street, Suite 3400 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 Securities registered pursuant to Section 12(g) of the Act: None Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐ No ☒ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No ☒ 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 has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report ☒ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act) Yes ☐ No ☒ The aggregate market value of the common units held by non-affiliates of the registrant on June 30, 2020, was $109 million based on a closing price on that date of $12.19 per unit as reported on the New York Stock Exchange. Documents incorporated by reference: None. Table of Contents TABLE OF CONTENTS Cautionary Statement Regarding Forward-Looking Statements ii Risk Factors Summary ii PART I Items 1. and 2. Business and Properties 1 Item 1A. Risk Factors 16 Item 1B. Unresolved Staff Comments 32 Item 3. Legal Proceedings 32 Item 4. Mine Safety Disclosures 32 PART II Item 5. Market for Registrant’s Common Equity, Related Unitholder Matters and Issuer Purchases of Equity 33 Securities Item 6. Selected Financial Data 33 Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations 34 Item 7A. Quantitative and Qualitative Disclosures About Market Risk 50 Item 8. Financial Statements and Supplementary Data 51 Item 9. Changes In and Disagreements with Accountants on Accounting and Financial Disclosure 90 Item 9A. Controls and Procedures 90 Item 9B. Other Information 92 PART III Item 10. Directors and Executive Officers of the Managing General Partner and Corporate Governance 93 Item 11. Executive Compensation 99 Item 12. Security Ownership of Certain Beneficial Owners and Management 102 Item 13. Certain Relationships and Related Transactions, and Director Independence 104 Item 14. Principal Accountant Fees and Services 111 PART IV Item 15. Exhibits, Financial Statement Schedules 114 Signatures 118 i Table of Contents CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS Statements included in this 10-K 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: the effects of the global COVID-19 pandemic; 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 production levels by our lessees; Ciner Wyoming LLC’s ("Ciner 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" in this Annual Report on Form 10-K for important factors that could cause our actual results of operations or our actual financial condition to differ. RISK FACTORS SUMMARY We are subject to a variety of risks and uncertainties, including risks related to our business, risks related to our indebtedness, risks related to our common stock and certain general risks, which could have a material adverse effect on our business, financial condition, results of operations and cash flows.