UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended June 30, 2026

OR

For the transition period from to

Commission file number: 001-41655

NioCorp Developments Ltd.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (720) 334-7066

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

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, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

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. ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

At December 31, 2025, the aggregate market value of the registrant’s voting and non-voting common equity held by non-affiliates of the registrant was $622.4 million based on the closing sale price as reported on the Nasdaq Stock Market. There were 145,849,630 common shares outstanding on September 25, 2026.

DOCUMENTS INCORPORATED BY REFERENCE

Not applicable.

TABLE OF CONTENTS

Table of Contents

Select Mining Definitions

Mineral Reserves and Resources

Information, including all mineral resource and mineral reserve estimates, concerning the Elk Creek Project in this Annual Report on Form 10-K has been prepared in accordance with the requirements of S-K 1300 and is based on the 2026 S-K 1300 Elk Creek Technical Report Summary, filed as Exhibit 96.1 to this Annual Report on Form 10-K. S-K 1300 requires us to disclose our mineral resources, in addition to our mineral reserves, as of the end of our most recently completed fiscal year. You are cautioned that mineral resources are subject to further exploration and development and are subject to additional risks and no assurance can be given that they will eventually convert to future reserves. Inferred resources, in particular, have a great amount of uncertainty as to their existence and their economic and legal feasibility. Investors are cautioned not to assume that any part or all of the inferred resource exists or is economically or legally mineable. In addition, the economic analysis described in the 2026 S-K 1300 Elk Creek Technical Report Summary was conducted in connection with the 2026 Elk Creek Study to demonstrate economic viability and support the determination of mineral reserves and is based on assumptions relating to discount rate, production rates, commodity prices, operating costs, capital expenditures, and other inputs that are subject to significant uncertainty. The results of the economic analysis are not a forecast or prediction of actual results for the periods covered, and actual results may differ materially from those projected by the economic analysis. There can be no assurance that the assumptions underlying the economic analysis will prove to be accurate or that the projected economics of the Elk Creek Project will be realized. See Item 1A., Risk Factors.

Currency

All dollar amounts in this Annual Report on Form 10-K are expressed in thousands of United States (“U.S.”) dollars unless otherwise indicated. The Company’s accounts are maintained in U.S. dollars and the Company’s consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”).

Risk Factors Summary

Investing in common shares, no par value, of the Company (“Common Shares”) involves numerous risks and uncertainties, as more fully described below. You should read these risks before you invest in our Common Shares. In particular, risks associated with our business include, but are not limited to, the following:

Risks Related to Our Business

Risks Related to Mining and Development

Risks Related to Government Regulation

Risks Related to Our Debt

Risks Related to the Common Shares

PART I

ITEM 1. BUSINESS

Introduction

NioCorp Developments Ltd. (“NioCorp,” “we,” “us,” “our,” or the “Company”) was incorporated under the laws of the Province of British Columbia under the Business Corporations Act (British Columbia) on February 27, 1987, under the name “IPC International Prospector Corp.” On May 22, 1991, we changed our name to “Kingston Resources Ltd.” On June 29, 2001, we changed our name to “Butler Developments Corp.” On February 12, 2009, we changed our name to “Butler Resource Corp.” On March 4, 2010, we changed our name to “Quantum Rare Earth Developments Corp.” On March 4, 2013, we changed our name to “NioCorp Developments Ltd.”

NioCorp is a United States Securities and Exchange Commission (“SEC”) reporting company, and we are also a Canadian reporting issuer in British Columbia, Alberta, Saskatchewan, Ontario, and New Brunswick. Our registered and records office is located at 1133 Melville Street, Suite 3500, Vancouver, British Columbia V6E 4E5 (ATTN: Blake, Cassels & Graydon LLP). Our principal executive office is located at 7000 South Yosemite Street, Suite 115, Centennial, Colorado 80112.

Business Operations

NioCorp, through ECRC (as defined below), is developing a critical minerals project that, if and when developed, will produce niobium, scandium, titanium and several rare earth products, including neodymium-praseodymium oxide, dysprosium oxide, terbium oxide, samarium-europium-gadolinium (“SEG”) carbonate, and heavy rare earth carbonate. Known as the “Elk Creek Project,” it is located near Elk Creek, Nebraska, in the southeast portion of the state.

Our primary business strategy is to advance our Elk Creek Project to commercial production. We are focused on securing project financing sufficient to cover initial capital costs and other related expenses necessary for the commencement and completion of construction, and carrying out our near-term planned work programs necessary to complete detailed design, development, and construction of the Elk Creek Project, as well as the commencement of early elements of project construction.

Corporate Structure

The Company’s business operations are conducted primarily through ECRC. The table below provides an overview of the Company’s current subsidiaries and their activities:

Historical Development of the Business

The acquisition of the carbonatite property located in Southeast Nebraska, USA (the “Elk Creek Property”) was closed in December 2010 and involved the purchase by NioCorp of all of the issued and outstanding common shares of a private British Columbia company, which in turn held 100% of the issued and outstanding shares of Elk Creek Resources Corp., a Nebraska corporation.

Between 2011 and 2020, the Company advanced the Elk Creek Project through the completion of field exploration programs, feasibility study development and reporting, updates to underground mine designs and supporting infrastructure, and the receipt of required permits from the State of Nebraska.

During fiscal year 2021, we obtained funding which allowed us to purchase land and mineral rights at the Elk Creek Property and continue early project execution activities. During fiscal year 2022, we focused efforts towards refining our Elk Creek Project mineral resource and mineral reserve estimates with respect to REEs. This work included additional assays of historical drill core to fill data gaps in the existing resource database and re-modeling. Based on this re-interpretation of the geologic data, an update to the mine plan was also completed. Based on this work, we issued a NI 43-101 technical report on June 28, 2022, and filed the 2022 S-K 1300 Elk Creek Technical Report Summary as an exhibit to our Annual Report on Form 10-K for the year ended June 30, 2022.

On March 17, 2023 (the “Closing Date”), the Company closed a series of transactions (the “GXII Transaction”) pursuant to the Business Combination Agreement, dated September 25, 2022 (the “Business Combination Agreement”), among the Company, GX Acquisition Corp. II (“GXII”), and Big Red Merger Sub Ltd (the “Closing”).

As a result of the GXII Transaction, among other matters, GXII became an indirect, majority-owned subsidiary of NioCorp and changed its name to “Elk Creek Resources Corp.”, which we refer to as “ECRC,” and the Common Shares and the Warrants that were assumed by NioCorp from GXII (the “NioCorp Assumed Warrants”) were listed for trading on Nasdaq under the symbols “NB” and “NIOBW,” respectively.

Pursuant to the Business Combination Agreement, the Sponsor Support Agreement, dated September 25, 2022, among GX Sponsor II LLC (the “Sponsor”), GXII, the Company and the other persons party thereto, and the Exchange Agreement, dated as of March 17, 2023, by and among NioCorp, ECRC and the Sponsor (the “Exchange Agreement”), after the Closing, the shares of Class B common stock of ECRC are exchangeable into Common Shares on a one-for-one basis, subject to certain equitable adjustments, under certain conditions. Of the issued and outstanding shares of Class B common stock of ECRC, 4,565,808 shares (the “Vested Shares”) were vested as of the Closing Date and are exchangeable at any time, and from time to time, until the tenth anniversary of the Closing Date and 3,391,596 shares (the “Earnout Shares”) are exchangeable until the tenth anniversary of the Closing Date, subject to certain vesting conditions. See Note 8 to the consolidated financial statements included in Part II, Item 8 hereof for additional information regarding the Class B common stock of ECRC.

In addition, during fiscal year 2026, the Company completed the acquisition of an additional 447.43 acres of land pursuant to existing option to purchase agreements ("OTPs"). As a result of these transactions, the Company now holds full ownership of all surface rights within the one-square-mile section in which it plans to construct both the underground critical minerals

mine and integrated surface processing facility associated with the Elk Creek Project. These acquisitions also include 1.6 acres of land adjacent to Highway 50 and County Road 721 that will be used for improvements to both roadways in order to establish the entrance to the project site on the north side of the Company’s owned lands.

On December 4, 2025, the Company, through its newly-formed subsidiary, NAMA, completed the acquisition of the manufacturing assets and intellectual property of FEA Materials LLC for $8.4 million in cash. The acquired assets include equipment and proprietary technology used to produce aluminum-scandium ("Al-Sc") master alloy through an innovative process that converts scandium oxide directly into Al-Sc master alloy, eliminating the need to first manufacture scandium metal. This technology is expected to meaningfully reduce processing complexity and cost relative to traditional methods. The acquisition strengthens the Company’s downstream commercialization strategy by potentially enabling the future production of Al-Sc master alloy in the United States, subject to completion and financing of the Elk Creek Project.

On February 26, 2026, the Company announced that construction of the main access to the underground portion (the "Portal Project") of the Elk Creek Project had commenced. The construction of the Elk Creek Project mine’s main entrance, known as a “portal,” will serve as the primary access point for personnel, equipment, and materials, as well as to deliver ore from the underground mine to the surface production plant. The Company also filed a formal “Notice of Commencement” with the Mine Safety and Health Administration ("MSHA") in conjunction with this effort. The Portal Project has an overall budget of $44.6 million, and through June 30, 2026, the Company has incurred approximately $5.6 million in construction costs.

During fiscal year 2025, the Company initiated a drilling program at the Elk Creek Project to support the conversion of a portion of its current indicated resources into measured resources and the subsequent conversion of a portion of its current probable mineral reserves into proven mineral reserves. This drilling program and related assay work were completed in fiscal year 2026, and formed the basis of the updated 2026 Elk Creek Study, which is summarized in the 2026 S-K 1300 Elk Creek Technical Report Summary filed as Exhibit 96.1 to this Annual Report on Form 10-K and as more fully described below under Item 2. “Properties.”

Recent Corporate Events

EXIM Bank Financing Process

As previously disclosed, on March 6, 2023, the Company announced the receipt of a Letter of Interest from the Export-Import Bank of the United States (“EXIM”) for potential debt financing, which may include a loan or loan guarantee, through EXIM’s “Make More in America” initiative to fund a portion of the project costs of the Elk Creek Project (the “EXIM Financing”).

NioCorp submitted a formal application to EXIM under EXIM’s “Make More in America” initiative on June 6, 2023. The Company was informed that its application received approval by the first of three reviews by the EXIM Transaction Review Committee on October 2, 2023. EXIM deployed additional resources to the processing of the Company’s application during the quarter ended December 31, 2023, and has retained financial and legal consultants to support EXIM’s due diligence on the Elk Creek Project. On April 15, 2024, the Company received a Preliminary Project Letter (the “PPL”) from EXIM. The PPL is a summary of EXIM’s initial due diligence findings and also includes a preliminary Indicative Term Sheet. The PPL identified additional project activities to be undertaken by the Company in conjunction with the EXIM evaluation process. These include an updated mine plan and updated Elk Creek Project capital costs on a final or close-to-final basis reflecting updated process flows.

NioCorp continues to work with EXIM to advance the Elk Creek Project through EXIM’s due diligence and loan application process. The completion of the 2026 Elk Creek Study satisfies a key EXIM due diligence requirement reflected in the PPL, and the Company now expects to advance to the next steps of the process relating to detailed engineering, procurement and construction contracting. The PPL included an indicative term sheet, which left open the total estimated amount of the EXIM Financing and provided that the amount of the EXIM Financing that could be made available for the Elk Creek Project will be scaled based on the number of U.S. jobs supported, both during construction and over the life of EXIM’s financing, subject to certain expectations regarding the ratio of debt-to-equity financing for the Elk Creek Project. The Company believes that the updated 2026 Elk Creek Study, with its updated economic analysis, mineral resource and mineral reserve estimates, and increased job creation projections, demonstrates that the Elk Creek Project satisfies the criteria for increased financing as contemplated by the PPL. However, NioCorp is currently unable to estimate the total amount of the EXIM Financing, if any, as well as how long the application process, including additional project activities identified by EXIM, may take, and there can be no assurances that NioCorp will be able to successfully negotiate a final commitment for the EXIM Financing, on acceptable terms, or at all.

During the fiscal year ended June 30, 2026, the Company raised approximately $467.2 million in net proceeds from equity financing transactions, which involved the issuance and sale of Common Shares, and pre-funded warrants to purchase Common Shares, in a series of registered offerings. For further discussion, see Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources.”

DoW Agreement

On August 4, 2025, ECRC entered into a Project Sub-Agreement (the “DoW Agreement”) with Advanced Technology International, an entity acting on behalf of the Defense Industrial Base Consortium under the authority of the U.S. Department of War (“DoW”). Subject to the terms and conditions of the DoW Agreement, ECRC is entitled to receive up to an aggregate of approximately $10.0 million of reimbursement payments from the DoW upon the achievement of certain project milestones related to engineering and additional reserve drilling, as well as preparing updated cost estimates, for the Elk Creek Project. As of June 30, 2026, NioCorp has received approximately $8.1 million of reimbursement payments under the DoW Agreement.

Shareholder Rights Plan Agreement

On November 21, 2025, the Company adopted a limited-duration shareholder rights plan (the "Rights Plan") pursuant to a Shareholder Rights Plan Agreement dated November 21, 2025 (the "Original Rights Plan Agreement"), between the Company and Computershare Investor Services Inc., as rights agent (the "Rights Agent"). One right (a "Right") was issued for each Common Share outstanding as of December 4, 2025, and a Right automatically attaches to each Common Share subsequently issued until the expiration of the Rights Plan. The Rights generally become exercisable only if a person or group acquires, or announces the current intention of commencing a take-over bid to acquire, beneficial ownership of 20% or more of the Company's outstanding Common Shares, other than through a permitted bid made in compliance with applicable Canadian take-over bid rules. If the Rights become exercisable, each holder of a Right, other than the acquiring person, would be entitled to purchase additional Common Shares at a discount to the then-current market price. The Rights Plan was not adopted in response to any specific take-over proposal. On April 6, 2026, following approval by the Company's shareholders at the Company's annual general meeting held on April 6, 2026, the Company and the Rights Agent entered into an Amended and Restated Shareholder Rights Plan Agreement (the "Amended Rights Plan Agreement"), which amended and restated the Original Rights Plan Agreement in its entirety. Under the Original Rights Plan Agreement, the Rights Plan would have expired on May 21, 2026. Under the Amended Rights Plan Agreement, the Rights Plan now expires at 5:00 p.m. (Toronto time) on the date of the Company's next annual general meeting.

Competitive Business Conditions

There is significant competition within the minerals industry to discover, acquire, and obtain project financing for, mineral properties considered to have commercial potential. We compete with others in efforts to obtain project financing and resources to advance the Elk Creek Project to construction and commercial operation, acquire and utilize mining and processing equipment, and hire qualified personnel. These other companies may be better capitalized than us and we may have difficulty in obtaining the financing and resources necessary to advance the Elk Creek Project to construction and commercial operation. There is currently a significant focus on domestic critical mineral supply among potential producers, processors and the U.S. Government. This includes recent government financing and policy support announced for other potential sources of critical minerals, which may alter the strategic importance of the Elk Creek Project and impact our ability to access funding or potential future government support. In addition, in competing for qualified personnel, we may be required to pay compensation or benefits relatively higher than those paid in the past, and the availability of qualified personnel may be limited in high-demand periods.

Once the Elk Creek Project begins commercial operation, we expect to face significant competition both domestically and globally for our products. The most prominent global competitor is China, which controls a substantial majority of the world’s scandium and REE production. China’s scandium and rare earth industries benefit from extensive government support, allowing Chinese companies to offer scandium and REEs at subsidized prices, often undercutting other producers. Moreover, Chinese companies have invested heavily in improving their processing capabilities, giving them a technological and cost advantage in the global market, and we believe, at the expense of world sustainability and labor standards. In recent years, China has also begun to implement export controls limiting the amount of scandium and REE products that are sold into the global market outside of China. We believe these controls have created a bifurcated market for scandium, dysprosium and terbium, causing prices outside China to be significantly higher than prices within China.

Cycles

The mining business is subject to mineral price cycles. The marketability of minerals and mineral concentrates is also affected by worldwide economic cycles. Demand has in the past, and may in the future, be subject to those same worldwide economic cycles. Fluctuations in supply and demand in various regions throughout the world are common. In addition, the niobium, scandium, titanium, and rare earth products, that we intend to produce at the Elk Creek Project are subject to additional commodity-specific price cycles resulting from, among other factors, demand for specific products, export controls, taxes and other tariffs and fees.

As NioCorp is a development stage issuer and has not yet generated any revenue from the operation of the Elk Creek Project, it is not currently significantly affected by changes in commodity demand and prices, except to the extent that these changes may impact the development of the Elk Creek Project. As it does not carry on production activities, NioCorp’s ability

to fund ongoing exploration is affected by the availability of financing, which is, in turn, affected by the strength of the economy and other general economic factors.

Economic Dependence

Other than land and mineral right option agreements and agreements between NioCorp and third parties for the purchase and sale of products to be produced from the Elk Creek Project (“offtake agreements”), NioCorp’s business is not substantially dependent on any contract such as a contract to sell the major part of its product or services or to purchase the major part of its requirements for goods, services or its raw materials, or any franchise or license or other agreement to use a patent, formula, trade secret, process or trade name upon which its business depends.

Government Regulation

The exploration and development of a mining prospect is subject to regulation by a number of federal and state government authorities. These include the United States Environmental Protection Agency (the “EPA”) and the United States Army Corps of Engineers (the “USACE”) as well as the various state and local environmental protection agencies. The regulations address many environmental issues relating to air, soil, and water contamination, and apply to many mining related activities including exploration, mine construction, mineral extraction, ore milling, water use, waste disposal, and use of toxic substances. In addition, we are subject to regulations relating to labor standards, occupational health and safety, mine safety, general land use, export of minerals, taxation, data protection, and data security. Many of the regulations require permits or licenses to be obtained, the absence of which and/or inability to obtain such permits or licenses will adversely affect our ability to conduct our exploration, development, and operation activities. The failure to comply with the regulations and terms of permits and licenses may result in fines or other penalties or in revocation of a permit or license or loss of a prospect.

General

While none of the lands on which the Elk Creek Project is proposed to be built are owned by the U.S. Government, mining rights on public lands are governed by the General Mining Law of 1872, as amended, which allows for the location of mining claims on certain federal lands upon the discovery of a valuable mineral deposit and compliance with location requirements. The exploration of mining properties and development and operation of mines is governed by both federal and state laws. Federal laws that govern mining claim location and maintenance and mining operations on federal lands are generally administered by the Bureau of Land Management. Additional federal laws, governing mine safety and health, also apply. State laws also require various permits and approvals before exploration, development or production operations can begin. Among other things, a reclamation plan must typically be prepared and approved, with financial assurance provided in the amount of projected reclamation costs. The financial assurance is used to ensure that proper reclamation takes place and will not be released until that time. Local jurisdictions may also impose permitting requirements, such as conditional use permits or zoning approvals.

Environmental Regulation

Our mineral projects are subject to various federal, state, and local laws and regulations governing protection of the environment. These laws are continually changing and, in general, are becoming more restrictive. The development, operation, closure, and reclamation of mining projects in the U.S. requires numerous notifications, permits, authorizations, and public agency decisions. Compliance with environmental and related laws and regulations requires us to obtain permits issued by regulatory agencies and to file various reports and keep records of our operations. Certain of these permits require periodic renewal or review of their conditions and may be subject to a public review process during which opposition to our proposed operations may be encountered. We are currently operating under various permits for activities connected to mineral exploration, reclamation, and environmental considerations. Our policy is to conduct business in a way that safeguards public health and the environment. We believe that our operations are conducted in material compliance with applicable laws and regulations.

Changes to current local, state, or federal laws and regulations in the jurisdictions where we operate could require additional capital expenditures and increased operating and/or reclamation costs. Although we are unable to predict what additional legislation, if any, might be proposed or enacted, additional regulatory requirements could impact the economics of our projects.

Environmental Regulation - U.S. Federal Laws

The Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”), and comparable state statutes, impose strict, joint, and several liability on current and former owners and operators of sites and on persons who disposed of or arranged for the disposal of hazardous substances found at such sites. It is not uncommon for the government to file claims requiring clean-up actions and/or demands for reimbursement for government-incurred clean-up costs or natural resource damages. It is also not uncommon for neighboring landowners and other third parties to file claims for personal injury and property damage allegedly caused by hazardous substances released into the environment. The Resource Conservation and

Recovery Act (“RCRA”), and comparable state statutes, govern the disposal of solid waste and hazardous waste and authorize the imposition of substantial fines and penalties for noncompliance, as well as requirements for corrective actions. CERCLA, RCRA, and comparable state statutes can impose liability for clean-up of sites and disposal of substances found on exploration, mining and processing sites long after activities on such sites have been completed.

The Clean Air Act, as amended (“CAA”), restricts the emission of air pollutants from many sources, including mining and processing activities. Any future mining operations by the Company may produce air emissions, including fugitive dust and other air pollutants from stationary equipment, storage facilities, and the use of mobile sources such as trucks and heavy construction equipment, which are subject to review, monitoring and/or control requirements under the CAA and state air quality laws. New facilities may be required to obtain permits before work can begin, and existing facilities may be required to incur capital costs in order to remain in compliance. In addition, permitting rules may impose limitations on our production levels or result in additional capital expenditures in order to comply with the rules.

The National Environmental Policy Act requires federal agencies to integrate environmental considerations into their decision-making processes by evaluating the environmental impacts of their proposed actions, including issuance of permits to mining facilities and assessing alternatives to those actions. If a proposed action could significantly affect the environment, the agency must prepare either a detailed statement known as an Environmental Impact Statement (“EIS”), or a less detailed statement known as an Environmental Assessment (“EA”). The EPA, other federal agencies, and any interested third parties can review and comment on the scope of the EIS or EA and the adequacy of any findings set forth in the draft and final EIS or EA. This process can cause delays in issuance of required permits or result in changes to a project to mitigate its potential environmental impacts, which can in turn impact the economic feasibility of a proposed project.

The Clean Water Act (“CWA”), and comparable state statutes, impose restrictions and controls on the discharge of pollutants into waters of the U.S. The discharge of pollutants into regulated waters is prohibited, except in accordance with the terms of a permit issued by the EPA or an analogous state agency. The CWA regulates storm water from mining facilities and requires a storm water discharge permit or Stormwater Pollution Prevention Plan for certain activities. Such a permit requires the regulated facility to monitor and sample storm water run-off from its operations. The CWA and regulations implemented thereunder also prohibit discharges of dredged and fill material in wetlands and other waters of the U.S. unless authorized by an appropriately issued permit. The CWA and comparable state statutes provide for civil, criminal, and administrative penalties for unauthorized discharges of pollutants, and impose liability on parties responsible for those discharges for the costs of cleaning up any environmental damage caused by the release and for natural resource damages resulting from the release.

The Safe Drinking Water Act (“SDWA”) and the Underground Injection Control (“UIC”) program promulgated thereunder, regulate the drilling and operation of subsurface injection wells. The EPA directly administers the UIC program in some states and in others the responsibility for the program has been delegated to the state. The program requires that a permit be obtained before drilling a disposal or injection well. Violation of these regulations and/or contamination of groundwater by mining-related activities may result in fines, penalties, and remediation costs, among other sanctions and liabilities under the SDWA and state laws. In addition, third-party claims may be filed by landowners and other parties claiming damages for alternative water supplies, property damages, and bodily injury.

Environmental Regulation − Nebraska

Nebraska has a well-developed set of environmental regulations and responsible agencies but does not have clearly defined regulations with respect to permitting mines. As such, review of the project and the issuance of permits by Nebraska agencies and regulatory bodies could potentially impact the total time to market for our Elk Creek Project. Other Nebraska regulations govern operating and design standards for the construction and operation of any source of air emissions and landfill operations. Any changes to these laws and regulations could have an adverse impact on our financial performance and results of operations by, for example, requiring changes to operating conditions, technical criteria, fees, or surety requirements. The most stringent permit related to air quality is known as a Prevention of Significant Deterioration (“PSD”) permit, which requires the applicant to demonstrate compliance with the National Ambient Air Quality Standards ("NAAQS") and Best Available Control Technology (“BACT”) for the control of air emissions. If the facility exceeds the potential to emit thresholds for such a permit and is thus subject to PSD requirements, permanent construction at the project site may not begin until the responsible agency issues the PSD permit. For facilities in Nebraska with potential emissions below PSD thresholds, a state air construction permit is needed. The state permit also requires a demonstration of compliance with NAAQS but does not require a BACT demonstration and further allows construction at a subject facility to proceed ahead of permit issuance through an established variance process. The Elk Creek Project has held a state air construction permit since June 2, 2020.

Human Capital

The Company’s ability to continue to progress the Elk Creek Project will depend on its ability to attract and retain individuals with (among other skills) financial, administrative, engineering, geological and mining skills, and knowledge of

our industry and targeted markets. Much of the necessary specialized skills and knowledge required by the Company as a mineral exploration company are available from the Company’s current management team and Board of Directors (the “Board”). The Company retains outside consultants if additional specialized skills and knowledge are required.

As of June 30, 2026, we had fourteen full-time employees as well as four contract employees. In addition, we use consultants with specific skills to assist with various aspects of our corporate affairs, project evaluation, due diligence, corporate governance, and property management.

Our compensation programs are designed to align compensation of our employees with the Company’s performance and to provide the proper incentives to attract, retain, and motivate employees to achieve superior results. The structure of our compensation programs balances competitive wages and benefits and incentive earnings for both short-term and long-term performance.

Our priority to maintain a culture of ethical performance as a core value is reflected in the Company’s Code of Business Conduct and Ethics (the “Code of Conduct”) and other related policies. Oversight is provided by the Company’s Board and, for specific areas of performance, by committees of the Board. Employees are required to review the Code of Conduct on a periodic basis. Our compensation programs also include consideration of ethical performance in determining incentive awards.

The Company also provides a robust suite of benefits to our employees, including 401(k) participation, medical-insurance options, and programs to encourage and support the whole person.

Forward-Looking Statements

This Annual Report on Form 10-K and the exhibits attached hereto contain “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and “forward-looking information” within the meaning of applicable Canadian securities legislation (collectively, “forward-looking statements”).

Forward-looking statements have been based upon our current business and operating plans, as approved by the Board, and may include statements regarding, among other matters, the financial and business performance of NioCorp; NioCorp’s anticipated results and developments in the operations of NioCorp in future periods; NioCorp’s planned exploration and development activities; the adequacy of NioCorp’s financial resources; NioCorp’s ability to secure sufficient project financing to complete construction and commence operation of the Elk Creek Project; NioCorp’s expectations on the form of future project financing; the necessity and impact of additional binding offtake agreements and the terms of such agreements, if any; NioCorp’s ability to receive a final commitment of financing from EXIM; future standards imposed by the U.S. federal government, if any; the estimated total upfront capital expenditure for the Elk Creek Project; NioCorp’s expectation and ability to produce niobium, scandium, titanium and the rare earth elements at the Elk Creek Project; NioCorp’s plans to produce and supply specific products and market demand for those products; NioCorp’s expectation that it will receive the full $10.0 million in reimbursement under the DoW Agreement; the intended use of our cash balance as of June 30, 2026, the proceeds from Warrant exercise issuances, and the reimbursement payments pursuant to the DoW Agreement; the Elk Creek Project’s ability to produce multiple critical metals; the Elk Creek Project’s projected ore production and mining operations over its expected mine life; statements with respect to the estimation of mineral resources and mineral reserves; statements with respect to projected product pricing, costs, and project economics; the exercise of options to purchase additional land parcels; the execution of contracts with engineering, procurement and construction companies; NioCorp’s possible future usage of artificial intelligence (“AI”) and the risks and challenges associated therewith; NioCorp’s ongoing evaluation of the impact of inflation, supply chain issues, tariffs, and geopolitical unrest on the Elk Creek Project’s economic model; construction of the Portal Project at the Elk Creek Project; and the creation of full time and contract construction jobs over the construction period of the Elk Creek Project.

Forward-looking statements are frequently, but not always, identified by words such as “expects,” “anticipates,” “believes,” “intends,” “estimates,” “potential,” “possible,” and similar expressions, or statements that events, conditions, or results “will,” “may,” “could,” or “should” (or the negative and grammatical variations of any of these terms) occur or be achieved. Any statements that express or involve discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions, or future events or performance (often, but not always, using words or phrases such as “expects” or “does not expect,” “is expected,” “anticipates” or “does not anticipate,” “plans,” “estimates,” or “intends,” or stating that certain actions, events, or results “may,” “could,” “would,” “might,” or “will” be taken, occur or be achieved) are not statements of historical fact and may be forward-looking statements. Forward-looking statements reflect material expectations and assumptions, including, without limitation, expectations and assumptions relating to: NioCorp’s ability to receive sufficient project financing for the construction of the Elk Creek Project on acceptable terms, or at all; the future price of and demand for metals, including Al-Sc alloy; the impact that Chinese restrictions have on pricing and demand including the existence of a bifurcated market between China and the rest of the world; and the stability of the financial and capital

markets. Such forward-looking statements reflect the Company’s current views with respect to future events and are subject to certain known and unknown risks, uncertainties, and assumptions. Many factors could cause actual results, performance, or achievements to be materially different from any future results, performance, or achievements that may be expressed or implied by such forward-looking statements, including, among others, risks related to the following: NioCorp’s requirement of significant additional capital; NioCorp’s ability to receive sufficient project financing for the construction of the Elk Creek Project on acceptable terms, or at all; NioCorp’s ability to achieve the required milestones and receive the full $10.0 million in reimbursement under the DoW Agreement; NioCorp’s ability to receive a final commitment of financing from EXIM or other debt financing or financial support on acceptable timelines, on acceptable terms, or at all; NioCorp’s ability to continue to meet Nasdaq listing standards; risks relating to the Common Shares, including price volatility, lack of dividend payments and dilution or the perception of the likelihood of any of the foregoing; the extent to which NioCorp’s level of indebtedness and/or the terms contained in agreements governing NioCorp’s indebtedness, if any, or other agreements may impair NioCorp’s ability to obtain additional financing, on acceptable terms, or at all; NioCorp’s limited operating history; NioCorp’s history of losses; the material weakness in NioCorp’s internal control over financial reporting, NioCorp’s efforts to remediate such material weakness and the timing of remediation; the possibility that NioCorp may qualify as a PFIC under the Code; the potential that the 2023 business combination with GXII could result in NioCorp becoming subject to materially adverse U.S. federal income tax consequences as a result of the application of Section 7874 and related sections of the Code; changes in tax laws and regulations; cost increases for NioCorp’s exploration and, if warranted, development projects; a disruption in, or failure of, NioCorp’s information technology systems, including those related to cybersecurity; equipment and supply shortages; variations in the market demand for, and prices of, niobium, scandium, titanium and rare earth products, including, without limitation, a reduction of demand for scandium from a downturn in capital spending for AI; impacts on the markets and pricing for scandium and rare earth products from the Chinese-based markets, including any future changes to export restrictions; current and future offtake agreements, joint ventures, and partnerships, including our ability to negotiate extensions to existing agreements or to enter into new agreements, on favorable terms or at all; NioCorp’s ability to negotiate definitive agreements for existing non-binding memoranda of understanding and non-binding term sheets; NioCorp's ability to attract qualified management; estimates of mineral resources and reserves; mineral exploration and production activities; technical and economic study results; the results of metallurgical testing; the results of technological research; unexpected variations in the quantity of ore, grade or recovery rates, or the presence of deleterious elements that would affect the process plant or waste removal; unexpected geotechnical and hydrogeological conditions from what was assumed in the mine designs; changes in demand for and price of commodities (such as fuel and electricity) and currencies; competition in the mining industry; changes or disruptions in the securities markets; legislative, political or economic developments, including changes in federal and/or state laws that may significantly affect the mining and scandium alloy industries; trade policies and tensions, including tariffs and other export controls; inflationary pressures; the impacts of climate change, as well as actions taken or required by governments related to strengthening resilience in the face of potential impacts from climate change; changes in other environmental and social factors; the need to obtain permits and comply with laws and regulations and other regulatory requirements; the timing and reliability of sampling and assay data; the possibility that actual results of work may differ from projections/expectations or may not realize the perceived potential of NioCorp’s projects; risks of accidents, equipment breakdowns, and labor disputes or other unanticipated difficulties or interruptions; the possibility of cost overruns or unanticipated expenses in development programs; operating or technical difficulties in connection with exploration, mining, development or scandium alloy production activities; management of the water balance at the Elk Creek Project site; land reclamation requirements related to the Elk Creek Project; the speculative nature of mineral exploration and development, including the risks of diminishing quantities or grades of reserves and resources; claims on the title to NioCorp’s properties; the infringement or loss of NioCorp's intellectual property rights; potential future litigation; NioCorp’s lack of insurance covering all of NioCorp’s operations; and changes in operating and capital costs, exchange rates, metallurgical performance, labor availability and other risks associated with the mining industry.

Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described herein. This list is not exhaustive of the factors that may affect any of the Company’s forward-looking statements. Forward-looking statements are statements about the future and are inherently uncertain, and actual achievements of the Company or other future events or conditions may differ materially from those reflected in the forward-looking statements due to a variety of risks, uncertainties, and other factors, including without limitation those discussed under Item 1A., Risk Factors below.

The Company’s forward-looking statements contained in this Annual Report on Form 10-K are based on the beliefs, expectations, and opinions of management as of the date of this Annual Report on Form 10-K. The Company does not assume any obligation to update forward-looking statements if circumstances or management’s beliefs, expectations, or opinions should change, except as required by law. For the reasons set forth above, investors should not attribute undue certainty to, or place undue reliance on, forward-looking statements.

Available Information

We maintain a website at http://www.niocorp.com. Our Common Shares are currently registered under Section 12(b) of the Exchange Act, and we are currently required to file reports on Forms 10-K, 10-Q, or 8-K. Our Annual Report on Form 10-K (which includes our audited consolidated financial statements), Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to reports filed or furnished pursuant to Sections 13(a) and 15(d) of the Exchange Act, are available on our website, free of charge, as soon as reasonably practicable after we electronically file such reports with, or furnish those reports to, the SEC. The SEC maintains an internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC (http://www.sec.gov). We do not intend to send security holders a printed version of our Annual Report as it will be available online.

We maintain a Code of Conduct, a copy of which may be found on our website in the “About Us” section under the main title “Corporate Governance.” Our Code of Conduct contains information regarding whistleblower procedures.

We are not including the information contained on or accessible through our website or the SEC’s website as a part of, or incorporating it by reference into, this Annual Report on Form 10-K.

ITEM 1A. RISK FACTORS

Our business activities are subject to significant risks, including those described below. You should carefully consider these risks. If any of the described risks occur, our business, financial position, and results of operations could be materially adversely affected. Such risks are not the only ones we face, and additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business. This report contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in the forward-looking statements as a result of a number of factors, including the risks described below. See “Forward-Looking Statements” under Item 1., “Business.”

Risks Related to Our Business

We will require significant additional capital to fund our business plan.

We will be required to make substantial capital expenditures to advance the Elk Creek Project to construction and commercial operation. We will also require funds for our ongoing capital needs and will be required to raise additional capital.

We expect that the Company will operate at a loss for the foreseeable future. The Company’s current planned cash needs are approximately $65 million to $75 million for the next twelve months. In addition to outstanding accounts payable and short-term liabilities, our planned expenditures over the next twelve months are expected to consist of expenditures relating to the advancement of the Elk Creek Project by NioCorp’s majority owned subsidiary, ECRC, corporate overhead costs, and estimated costs related to securing financing necessary for advancement of the Elk Creek Project.

We expect to use our cash balance as of June 30, 2026, as well as the proceeds from Warrant and options to purchase Common Shares ("Options") exercise issuances, and the reimbursement payments pursuant to the DoW Agreement, to fund our planned expenditures for the next twelve months. However, additional work is required in order to advance the Elk Creek Project, which will require additional financing. If the Company were able to obtain additional funding, the Company would be able to accelerate planned expenditures ahead of its current schedule. In addition, to the extent that EXIM requests further project activities to be undertaken in connection with the diligence process, the Company would require additional funding to complete such activities. The Company’s ability to continue operations and fund our current work plan is dependent on management’s ability to secure additional financing.

We have not yet commenced commercial production at any of our properties and, as such, have not generated positive cash flows to date and have no reasonable prospects of doing so unless successful commercial production can be achieved at our Elk Creek Project. We expect to continue to incur negative investing and operating cash flows until such time as we enter into successful commercial production. This will require us to deploy our working capital to fund such negative cash flow and to seek additional sources of financing. There is no assurance that any such financing sources will be available or sufficient to meet our requirements. There is no assurance that we will be able to continue to raise equity capital or to secure additional debt financing, or that we will not continue to incur losses.

The 2026 S-K 1300 Elk Creek Technical Report Summary includes an estimated total upfront capital expenditure for the Elk Creek Project of approximately $1,849 million. The actual amount of capital expenditure required to successfully achieve commercial production at the Elk Creek Project is subject to, among other factors, the timing and actual cost of further exploration, preparing feasibility studies, permitting, engineering, and the construction of infrastructure, mining and processing

facilities. We anticipate financing the estimated total upfront capital expenditure for the Elk Creek Project with debt financing (including the potential EXIM Financing) and additional equity financing.

The potential EXIM Financing is subject to, among other matters, the satisfactory completion of due diligence, including the additional project activities identified in the PPL, the negotiation and settlement of final terms, and the negotiation of definitive documentation. The PPL included an indicative term sheet, which left open the total estimated amount of the EXIM Financing and provided that the amount of the EXIM Financing that could be made available for the Elk Creek Project will be scaled based on the number of U.S. jobs supported, both during construction and over the life of EXIM’s financing, subject to certain expectations regarding the ratio of debt-to-equity financing for the Elk Creek Project. However, NioCorp is currently unable to estimate the total amount of the EXIM Financing, if any, as well as how long the application process, including additional project activities identified by EXIM, may take, and there can be no assurances that NioCorp will be able to successfully negotiate a final commitment for the EXIM Financing, on acceptable terms, or at all.

Agreements we enter into may contain restrictions on our ability to raise additional financing on reasonable terms or at all. For example, pursuant to the Exchange Agreement, NioCorp is restricted from issuing equity or equity-linked securities (other than Common Shares) or any preferred equity or non-voting equity if such issuance would adversely impact the rights of the holders of the shares of Class B common stock of ECRC, without the consent of the holders of a majority of the shares of Class B common stock of ECRC. Additionally, sales of substantial amounts of securities may have a highly dilutive effect on our ownership or share structure. Sales of a large number of Common Shares in the public markets, or the potential for such sales, could decrease the trading price of the Common Shares and could impair our ability to raise capital through future sales of Common Shares. There is significant uncertainty that we will be able to secure any additional financing in the current equity or debt markets.

Our ability to obtain necessary funding depends upon a number of factors, including, without limitation, the status of the national and worldwide economy, including international trade restrictions and policies, the demand for and the price of the products we intend to produce and our ability to negotiate satisfactory offtake arrangements for the products we intend to produce at the Elk Creek Project. We are actively pursuing additional sources of debt and equity financing, and while we have been successful in doing so in the past, there can be no assurance we will be able to obtain any such additional financing on acceptable terms, if at all. Our inability to access sufficient capital for our operations and the Elk Creek Project could have a material adverse effect on our financial condition, results of operations, or prospects.

We have a limited operating history on which to base an evaluation of our business and prospects.

Since our inception, we have had no revenue from operations. We have no history of producing products from any of our properties, and our assumptions related to the risks we may face in the future related to the Elk Creek Project may change. Our Elk Creek Project is a development stage property. Advancing our Elk Creek Project from a development stage property to a production stage property will require significant capital and time, and successful commercial production from the Elk Creek Property will be subject to permitting and construction of the mine, processing plants, roads, and other related works and infrastructure. As a result, we are subject to all of the risks associated with developing and establishing new mining operations and business enterprises including:

The costs, timing, and complexities of exploration, development, engineering, and construction activities may be increased by the location of our properties and competition from other mineral exploration and mining companies. It is common for

exploration companies to experience unexpected problems and delays during development, if commenced, including engineering, procurement, construction, commissioning, and ramp-up delays. Accordingly, our activities may not result in profitable operations and we may not succeed in establishing operations or profitably producing products at any of our current or future properties, including our Elk Creek Project.

We have a history of losses and expect to continue to incur losses in the future.

We have incurred losses since inception, have negative cash flow from operating activities, and expect to continue to incur losses in the future. We incurred a net loss attributable to the Company of $48.6 million for the year ended June 30, 2026, and $17.4 million for the year ended June 30, 2025.

We expect to continue to incur losses unless and until such time as one of our properties enters into commercial production and generates sufficient revenues to fund continuing operations. We recognize that if we are unable to generate significant revenues from operations and dispositions of our properties, we will not be able to earn profits or continue operations. At this early stage of our operation, we also expect to face the risks, uncertainties, expenses, and difficulties frequently encountered by companies at the start-up stage of their business development. We cannot be sure that we will be successful in addressing these risks and uncertainties and our failure to do so could have a materially adverse effect on our financial condition.

Increased costs could affect our financial condition.

We anticipate that costs at our projects that we may explore or develop, including the Elk Creek Project, will frequently be subject to variation from one year to the next due to a number of factors, such as changing ore grade, metallurgical performance, and revisions to mine plans, if any, in response to the physical shape and location of the ore body. In addition, costs are affected by the price of commodities such as fuel, steel, aluminum, iron, chemicals, natural gas, fresh water, and electricity, as well as by government actions such as tariffs. Such commodities are at times subject to volatile price movements, including increases that could make production at certain operations less profitable or not profitable at all. For example, the 2026 S-K 1300 Elk Creek Technical Report Summary includes an estimated total upfront capital expenditure for the Elk Creek Project of approximately $1,849 million, including a contingency of 14%, which is an increase of approximately $708 million compared to the estimated total upfront capital expenditure for the Elk Creek Project of approximately $1,141.0 million that was included in the 2022 S-K 1300 Elk Creek Technical Report Summary. The increase in estimated total upfront capital expenditure for the Elk Creek Project is primarily driven by a substantially redesigned processing plan and mining operation producing eight critical minerals and significant inflationary impacts since the 2022 S-K 1300 Elk Creek Technical Report Summary. The actual amount of capital expenditure required to successfully achieve commercial production at the Elk Creek Project is subject to, among other factors, the timing and actual cost of further exploration, preparing feasibility studies, permitting, engineering and the construction of infrastructure, mining, and processing facilities. A material increase in costs at any significant location could have a significant effect on our profitability.

We may be unable to successfully negotiate final, definitive offtake agreements, which could have a material adverse effect on our ability to secure project financing and establish the commercial viability of the Elk Creek Project.

We have entered into offtake agreements related to our Elk Creek Project, that cover the sale of 75% of our planned ferroniobium production for the first ten years of commercial operation. We expect that we will need to enter into additional offtake agreements to obtain sufficient project financing to cover initial capital costs and other related expenses, and to establish the commercial viability of the Elk Creek Project. We have entered into non-binding memoranda of understanding and non-binding term sheets related to the offtake of the remainder of the ferroniobium, as well as portions of our expected production of scandium and 100% of our titanium and rare earth production, that we expect to produce from the Elk Creek Project for the first ten years of commercial operation. We may be unable to negotiate final terms and agreements with these or other companies in a timely manner, or at all, and there is no guarantee that the terms of any final agreement will be the same or similar to those currently contemplated. Final terms may include less favorable pricing structures or volume commitments, reduced contract durations and other adverse changes. Delays in negotiating final agreements could slow our initial commercialization, and failure to agree to definitive terms for sales of sufficient volumes of our products could prevent us from growing our business. To the extent that terms in our initial purchase and offtake agreements may influence negotiations regarding future contracts, the failure to negotiate favorable final terms in respect of our current negotiations could have a material negative impact on our growth and profitability. Further, our prospective counterparties may cancel or delay entering into definitive agreements for a variety of reasons, some of which may be outside of our control. Any failure to enter into such definitive agreements on a timely basis, on favorable terms, or at all, could have a material adverse effect on our ability to secure project financing and establish the commercial viability of the Elk Creek Project.

Any failure of our counterparties to meet their obligations to us or to third parties with respect to our offtake agreements, supply agreements or other commercial agreements could have a material adverse effect on our ability to secure project financing and establish the commercial viability of the Elk Creek Project.

We have entered into offtake agreements, and may enter into joint ventures or partnership arrangements, including additional offtake agreements, with other parties in relation to the exploration, development, and production of certain of the properties in which we have an interest. In addition, we expect to enter into other agreements, including Engineering, Procurement, and Construction (“EPC”) agreements, as well as agreements related to the supply of natural gas and electricity to the Elk Creek Project.

Any failure of our counterparties to meet their obligations to us or to third parties, or any disputes with respect to the parties’ respective rights and obligations, price fluctuations and termination provisions related to such agreements, or our ability to negotiate extensions to existing agreements or to enter into new agreements, on favorable terms or at all, could have a material adverse effect on us, the development and production at our properties, including the Elk Creek Project, the joint ventures, if any, or their properties and therefore could have a material adverse effect on our ability to secure project financing and establish the commercial viability of the Elk Creek Project.

A disruption in, or failure of our third-party service providers’ IT systems, including those related to cybersecurity, could adversely affect our business operations and financial performance.

We rely on the accuracy, capacity, and security of our third-party service providers’ IT systems for the operations of many of our business processes and to comply with regulatory, legal, and tax requirements. We are dependent on third parties to provide important IT services relating to, among other things, operational technology at our facilities, human resources, electronic communications, and certain finance functions. Despite the security measures that our third-party service providers have implemented, including those related to cybersecurity, we have experienced, and may experience in the future, cybersecurity incidents. Cybersecurity incidents and similar attacks vary in their form and can include the deployment of harmful malware or ransomware, denial-of-service attacks, and other attacks, which may affect business continuity and threaten the availability, confidentiality and integrity of our systems and information, and the systems and information of our third-party service providers. Cybersecurity incidents can also include employee or personnel failures, fraud, phishing or other social engineering attempts or other methods to cause confidential information, payments, account access or access credentials, or other data to be transmitted to an unintended recipient. Cybersecurity threat actors also may attempt to exploit vulnerabilities in software that is commonly used by companies in cloud-based services and bundled software. We have experienced cybersecurity threats and cybersecurity incidents in the past, and may experience cybersecurity threats and cybersecurity incidents in the future. To date, we have not identified any risks from cybersecurity threats, including as a result of previous cybersecurity incidents, that have had or are reasonably likely to have, a material impact on our business operations or financial condition.

Though our third-party service providers have controls in place, we cannot provide assurance that a cybersecurity incident will not occur in the future. Furthermore, we may have little or no oversight with respect to security measures employed by third-party service providers, which may ultimately prove to be ineffective at countering threats. Cybersecurity threats or incidents or disruptions of our third-party service providers’ IT systems could interrupt our ability to manage and operate our business, impact data, and adversely affect our business operations and financial performance, including major disruptions to business operations, loss of intellectual property, release of confidential information, alteration or corruption of data or systems, costs related to remediation or the payment of ransom, and litigation including individual claims or consumer class actions, commercial litigation, administrative, and civil or criminal investigations or actions, regulatory intervention and sanctions or fines, investigation and remediation costs and possible prolonged negative publicity. In addition, we have incurred costs in connection with the remediation of cybersecurity incidents in the past and we may be required to incur significant costs to protect against and, if required, remediate the damage caused by cybersecurity incidents, disruptions or system failures in the future.

We may also be required to comply with cybersecurity standards imposed by the U.S. Government as a condition of entering into government contracts or receiving federal financial assistance. Any failure to comply with these standards, whether or not resulting in a cybersecurity incident or disruption, could restrict our ability to receive financing from the U.S. Government or to bid for, be awarded and perform contracts with the U.S. Government.

A shortage of equipment and supplies could adversely affect our ability to operate our business.

We are dependent on various supplies and equipment to carry out our mining exploration and, if warranted, project development operations. The shortage of such supplies, equipment, and parts could have a material adverse effect on our ability to carry out our operations and could therefore limit, or increase the cost of, production. Ongoing disruptions to the world’s economy, including issues related to supply chains, inflation, tariffs and trade tensions, and increased raw material and labor costs, may delay our ability to secure supplies and equipment for the Elk Creek Project on a timely basis.

We may use AI in our business, and challenges with properly managing its use could result in reputational harm, competitive harm and legal liability, and could have adverse effects on our results of operations, financial condition, liquidity and cash flows.

We may incorporate AI solutions into our business, and we may leverage AI, including generative and agentic AI, into our business operations. Our competitors or other third parties, may incorporate AI into their business more quickly or more successfully than we do, which could impair our ability to compete effectively and could adversely affect our results of operations. In addition, there are significant risks in using AI, and there can be no assurance that the use of AI will enhance our business or be beneficial to our business operations, including our efficiency or our profitability.

Additionally, if our AI applications, or the AI applications of third parties, are based on data, algorithms or other inputs that are flawed, or if our AI applications, or the AI applications of third parties, assist us in producing content, analyses or recommendations that are, or are alleged to be, deficient, inaccurate or biased, our business, results of operations and financial conditions may be adversely affected. The increased use of AI applications generally has resulted in, and may in the future result in, cybersecurity incidents that implicate the personal data of end users of such applications. Any such cybersecurity incidents related to our own use of AI applications may increase our cybersecurity risks, as well as the cybersecurity risks of third parties, which could adversely affect our reputation and results of operations. AI also presents emerging ethical issues, and if our use of AI becomes controversial, we may experience brand, reputational or competitive harm, or legal liability. The rapid evolution of AI, including the potential regulation of AI by governmental or other regulatory agencies, will require significant resources to develop, test and implement AI ethically and to minimize any unintended, harmful impacts.

We may experience difficulty attracting and retaining qualified management to meet the needs of our anticipated growth, and the failure to manage our growth effectively could have a material adverse effect on our business and financial condition.

We are dependent on a relatively small number of key employees, including our Chief Executive Officer. The loss of any officer could have an adverse effect on us. We have no life insurance on any individual, and we may be unable to hire a suitable replacement for them on favorable terms, should that become necessary. Further, the specialized nature of our model as summarized in the 2026 S-K 1300 Elk Creek Technical Report Summary may make qualified persons difficult to replace, which could have a material adverse effect on our business and financial condition.

The effect on the capital markets and the economy of recent global events, including inflation, volatility in commodity prices, supply chain uncertainty, tariffs and trade tensions, and increases in raw material and labor costs, could have an adverse effect on NioCorp’s business plans, financial condition, and liquidity.

Certain events have affected, and continue to affect, the global and United States economies, including increased inflation, volatility in commodity prices, supply chain uncertainty, tariffs and trade tensions, and increases in raw material and labor costs. We cannot predict how this will affect our business, but the impact may be adverse.

Although it is not possible to predict the ultimate impact of these factors on NioCorp’s business plans, financial position, or liquidity, such impacts that may be material include, but are not limited to: (i) delays in the completion of the mine and surface engineering designs and uncertainty regarding our ability to finalize necessary EPC agreements as a result of disruptions in the businesses of our engineering consultants and key contractors for the Elk Creek Project, (ii) reduced availability and increased costs of employees, (iii) a negative impact on our liquidity position, and (iv) increased costs and less ability to access funds in the capital markets. The full extent to which these factors may continue to impact our business will depend on future developments, which continue to be highly uncertain and cannot be predicted at this time.

In addition, we cannot predict the impact that recent global events, including inflation, volatility in commodity prices, supply chain uncertainty, tariffs and trade tensions, and increases in raw material and labor costs will have on our customers, suppliers, vendors, and other business partners, and each of their financial conditions; however, any material effect on these parties could adversely impact us.

It may be difficult to enforce judgments or bring actions outside the U.S. against us and certain of our directors.

We are a Canadian corporation and, as a result, it may be difficult or impossible for an investor to do the following:

We may not receive any proceeds from the exercise of our outstanding Warrants, and the potential adverse effect on the prevailing market prices for our Common Shares as a result of sales, or the perception of future sales, of Common Shares could adversely affect our ability to raise additional capital.

Upon exercise, we will receive the cash exercise price of our outstanding Warrants (assuming, that they are not exercised on a cashless basis, as applicable). We believe the likelihood that holders will exercise their Warrants, and therefore, the amount of cash proceeds that we would receive, is, among other things, dependent upon the market price of our Common Shares. For so long as the market price for our Common Shares is less than the applicable exercise price of the Warrants, we believe such holders will be unlikely to exercise their Warrants. The potential adverse effect on the prevailing market price of our Common Shares as a result of sales of Common Shares by us or by other security holders, or the perception that such sales may occur, could keep the market price for our Common Shares below the applicable exercise price of the Warrants. Accordingly, the holders of the Warrants may not exercise their Warrants before they expire, and we may not receive any proceeds from the exercise of the outstanding Warrants.

We may not recognize the full value of the DoW Agreement.

Subject to the terms and conditions of the DoW Agreement, the DoW will reimburse ECRC for a portion of the costs incurred by ECRC under the DoW Agreement and ECRC is entitled to receive up to an aggregate of approximately $10.0 million of reimbursement payments from the DoW upon the achievement of certain project milestones. If the Company is not successful in achieving the milestones required under the DoW Agreement or if the reimbursements sought by the Company are rejected or the DoW Agreement is terminated prior to completion of all milestones, the Company may not receive all of the payments as reimbursements for expenses incurred as expected under the DoW Agreement.

The Company has identified a material weakness in its internal control over financial reporting. If not remediated, the Company’s failure to establish and maintain effective disclosure controls and procedures and internal control over financial reporting could result in material misstatements in its financial statements and a failure to meet its reporting and financial obligations, each of which could have a material adverse effect on the Company’s financial condition and the trading price of the Common Shares.

Our management has identified a material weakness in its internal control over financial reporting relating to a deficiency in the principles associated with the control activities component of internal control based on the criteria established by the COSO Framework (as defined below), that constitute a material weakness. A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of a company’s annual or interim financial statements will not be prevented or detected on a timely basis.

As discussed in Item 9A, “Controls and Procedures,” of this Annual Report on Form 10-K, the Company’s management has assessed the effectiveness of its internal control over financial reporting and its disclosure controls and procedures and concluded that they were not effective as of June 30, 2026.

The Company is committed to remediating its material weakness as promptly as possible. Management is in the process of implementing its remediation plan. However, there can be no assurance as to when the material weakness will be remediated or that additional material weaknesses will not arise in the future. If the Company is unable to maintain effective internal control over financial reporting, its ability to record, process and report financial information timely and accurately could be adversely affected, which could subject the Company to litigation or investigations, require management resources, increase costs, negatively affect investor confidence and adversely impact the trading price of the Common Shares.

We may face litigation and other risks as a result of the material weakness in our internal control over financial reporting.

We identified a material weakness in our internal control over financial reporting that existed as of June 30, 2026. As a result of such material weakness and other matters raised or that may in the future be raised by the SEC or the Canadian securities regulators, we face potential for litigation or other disputes, which may include, among others, claims invoking the federal and state securities laws, contractual claims or other claims arising from the material weakness in our internal control over financial reporting and the preparation of our financial statements. As of the date of this Annual Report on Form 10-K, we have no knowledge of any such litigation or dispute. However, we can provide no assurance that such litigation or dispute will not arise in the future. Any such litigation or dispute, whether successful or not, could adversely affect our business, financial condition and results of operations.

Risks Related to Mining and Development

We face numerous uncertainties in estimating our mineral reserves and resources and inaccuracies in, or changes to, our estimates or the factors and assumptions on which they are based, including with respect to the economic analysis conducted

in connection with the 2026 S-K 1300 Elk Creek Technical Report Summary, could result in lower than expected revenues, higher than expected costs, and decreased profitability.

A mineral is economically recoverable when the price at which we may sell the mineral exceeds the costs and expenses of mining and selling the mineral. Forecasts of our future performance are based on, among other things, estimates of our mineral reserves. We base our reserve and resource information on engineering, economic, and geological data assembled and analyzed by qualified persons, which include various engineers and geologists on our staff and with third parties. Our estimates are also subject to SEC regulations regarding classification of reserves and resources, including S-K 1300. Our reserve and resource estimates as to both quantity and quality are updated from time to time to reflect additional information received. There are numerous uncertainties inherent in estimating quantities and qualities of mineral reserves and resources, including many factors beyond our control.

Estimates of mineral reserves and resources necessarily depend upon a number of variable factors and assumptions, any one of which may, if incorrect, result in an estimate that varies considerably from actual results. These factors and assumptions include, but are not limited to:

The conversion of reported mineral resources to mineral reserves should not be assumed, and the reclassification of reported mineral resources from lower to higher levels of geological confidence should not be assumed. As such, actual mineral tonnage recovered from identified reserves, and revenues and expenditures with respect to our reserves, may vary materially from estimates. Thus, these estimates may not accurately reflect our actual reserves. Any material inaccuracy in, or changes to, our estimates related to our reserves, or the underlying factors and assumptions, could result in lower-than-expected revenues, higher-than-expected costs, or decreased profitability, which could materially and adversely affect our business, results of operations, financial position, and cash flows.

In addition, the economic analysis described in the 2026 S-K 1300 Elk Creek Technical Report Summary that was conducted in connection with the 2026 Elk Creek Study to demonstrate economic viability and support the determination of mineral reserves may be impacted by the variables listed above, as well as assumptions relating to discount rates, future production rates, commodity prices, operating costs, capital expenditures, and other inputs that are subject to significant uncertainty. For example, the initial capital cost estimate for the Elk Creek Project as described in the 2026 S-K 1300 Elk Creek Technical Report Summary has a contingency level of 14%. The results of the economic analysis are not a forecast or prediction of actual results for the periods covered, and actual results may differ materially from those projected by the economic analysis. There can be no assurance that the assumptions underlying the economic analysis will prove to be accurate or that the projected economics of the Elk Creek Project will be realized. Any material inaccuracy in, or change to, our estimates related to our economic analysis could result in lower than expected revenues, higher than expected costs, or decreased profitability, which could materially and adversely affect our business, results of operations, financial position, and cash flows.

Price volatility could have dramatic effects on our results of operations and our ability to obtain financing for the Elk Creek Project and execute our business plan.

The price of commodities varies on a daily basis. Niobium is a specialty metal and not a commonly traded commodity such as copper, zinc, gold, or iron ore. The price of niobium tends to be set through a limited long-term offtake market, contracted between very few suppliers and purchasers. The world’s largest supplier of niobium, Companhia Brasileira de Metalurgia e Mineração, supplies approximately 85% of the world’s niobium. Any attempt to suppress the price of niobium by such supplier, or an increase in production by any supplier in excess of any increased demand, would have negative

consequences on the price of niobium and, potentially, on our value. The price of niobium may also be reduced by the discovery of new niobium deposits, which could not only increase the overall supply of niobium (causing downward pressure on its price) but could draw new firms into the niobium industry that would compete with us.

Sc2O3 is used in solid oxide fuel cells and has the potential to become a valuable alloy with aluminum in the aerospace and automotive industries. Supply of scandium has been sporadic in recent years, and there are no primary scandium mines in the world at present. Production primarily occurs as a by-product from existing metallurgical plants, primarily in Russia, Canada, the Philippines, and China. Our management believes the Elk Creek Project would significantly increase the world’s supply of scandium trioxide. Although the Company’s market studies indicate a positive outlook for demand, there is no assurance at present that the Company could sell all of its production. In addition, the sale of scandium represents a significant portion of the Elk Creek Project revenue; achieving the revenue projected in the Company’s studies is subject to market growth in scandium, which is a developing market with a risk of oversupply and/or undersupply disrupting pricing.

Titanium metal is used in various superalloys and other applications for aerospace applications, armor, and medical implants, and in oxide form is a key component of pigments used in paper, paint, and plastics. The Elk Creek Project would produce a small quantity of TiCl4 relative to other producers. As a small producer, we would be subject to fluctuations in the price of TiCl4 that would result from normal variations in supply and demand for this commodity.

In addition, the niobium, scandium, titanium, neodymium-praseodymium oxide, dysprosium oxide, terbium oxide, SEG carbonate and heavy rare earth carbonate, that we intend to produce at the Elk Creek Project are also subject to additional commodity-specific price cycles resulting from, among other factors, export controls, taxes and other tariffs and fees. Volatility in the demand for, and prices of, the niobium, scandium, titanium, and potentially, rare earth products, that we intend to produce at the Elk Creek Project may adversely affect the overall value of the Elk Creek Project and impact our ability to obtain financing for the Elk Creek Project on acceptable terms, or at all.

Furthermore, supply-side factors have a significant influence on price volatility for our planned products. Production of scandium and REEs is dominated by Chinese producers. The Chinese Central Government regulates production through quotas and environmental standards and, to a lesser extent, import regulation. It has changed, and may continue to change, those production quotas, environmental standards and import regulations. Over the past few years, the Chinese market has undergone significant restructuring in line with Chinese Central Government policy. However, periods of oversupply or speculative trading in scandium and REEs can lead to significant fluctuations in the market prices of these products. In recent years, China has also begun to implement export controls. We believe these controls have created a bifurcated market for scandium, dysprosium and terbium, causing prices outside China to be significantly higher than prices within China. Any easing of these export controls by China, or the development of alternative sources of supply, could have a material adverse effect on our business, financial condition and results of operations.

The nature of mineral exploration and production activities involves a high degree of risk and the possibility of uninsured losses.

Exploration for and the production of minerals is highly speculative and involves much greater risk than many other businesses. Most exploration programs do not result in the discovery of mineralization, and any mineralization discovered may not be of sufficient quantity or quality to be profitably mined. Our operations are, and any future development or mining operations we may conduct will be, subject to all of the operating hazards and risks normally incident to exploring for and developing mineral properties, such as, but not limited to:

Any of these risks can materially and adversely affect, among other things, the development of properties, production quantities and rates, costs and expenditures, potential revenues, and production dates. We currently have very limited insurance to guard against some of these risks. If we determine that capitalized costs associated with any of our mineral interests are not likely to be recovered, we would incur a write-down of our investment in these interests. All of these factors may result in losses in relation to amounts spent that are not recoverable, or that result in additional expenses.

We have no history of producing commercial products from our current mining properties and there can be no assurance that we will successfully establish mining operations or profitably produce minerals.

We have no history of producing commercial products from our current mining properties. We do not produce commercial products and do not currently generate operating earnings. While we seek to move our Elk Creek Project from a development stage property to a production stage property, such efforts will be subject to all of the risks associated with establishing new mining operations and business enterprises, including:

It is common in new mining and processing operations to experience unexpected problems and delays during engineering, procurement, construction, commissioning, and initial operations. In addition, our management and workforce will need to be expanded, and sufficient housing and other support systems for our workforce will have to be established. This could result in delays in the commencement of production and increased costs of production. Accordingly, we cannot assure you that our activities will result in profitable operations or that we will successfully establish mining and processing operations.

Results of metallurgical testing by us may not be favorable to, or as expected by, us.

We have completed significant bench, mini-pilot, and pilot scale metallurgical testing on material from the Elk Creek Project and will continue to complete necessary metallurgical testing at the bench, mini-pilot, and pilot scale as the exploration and, if warranted, development of the Elk Creek Project progresses. There can be no assurance that the results of such metallurgical testing will be favorable to, or will be as expected by, us. Furthermore, there can be no certainty that metallurgical recoveries obtained in bench or pilot scale tests will be achieved in either subsequent testing or commercial operations. The development of a complete metallurgical process to produce saleable final products from the Elk Creek Project is a complex and resource-intensive undertaking that may result in overall schedule delays and increased project costs for us.

The success of our business will depend, in part, on the growth of existing and emerging uses for scandium and rare earth products.

We intend to produce scandium and rare earth products at the Elk Creek Project that are used in critical industries, including AI data centers, electronics, aerospace and defense systems, robotics, and other advanced technologies. The success of our business depends, in part, on the continued growth of these end-markets and the successful commercialization of scandium and rare earth products. If the market for these existing and emerging technologies does not grow as we expect, grows slower than we expect, or if the demand for our products in these markets decreases, then our business, prospects, financial condition and operating results could be harmed. Although periods of high market prices would generally be beneficial to our financial performance, any such period could also create economic pressure to identify or create alternate technologies that ultimately could depress the long-term demand for our products. Any unexpected costs or delays in the production of scandium or rare earth products, or less than expected demand for the existing and emerging technologies that use scandium or rare earth products, could have a material adverse effect on the results of our operations.

Our recovery process for our planned products has been evaluated at a demonstration scale but has not been fully validated on a commercial scale.

The 2026 S-K 1300 Elk Creek Technical Report Summary describes the process by which we expect to recover scandium, niobium, titanium and the rare earth products from the Elk Creek Project’s ore body. Although demonstration-scale testing has achieved the targeted recovery rates, the full recovery and separation process has not been operated on a commercial scale or with actual production-stream materials at commercial throughput, and commercial samples of separated products have not yet been produced through the complete process. There can be no assurance that the recovery process will perform as designed on a commercial scale, produce products meeting required purity and quality specifications, or achieve the recoveries assumed in the 2026 S-K 1300 Elk Creek Technical Report Summary. Failure to validate the recovery process on a commercial scale could reduce the Elk Creek Project’s revenue, adversely affect the commercial viability of the Elk Creek Project, and have a material adverse effect on our business, results of operations, and financial condition.

Estimates of resources and reserves are subject to evaluation uncertainties that could result in project failure.

Our exploration and future mining operations, if any, are and would be faced with risks associated with being able to accurately predict the quantity and quality of resources/reserves within the earth using statistical sampling techniques. Estimates of any resources/reserves on any of our properties would be made using samples obtained from appropriately placed trenches, test pits, underground workings, and intelligently designed drilling. There is an inherent variability of assays between check and duplicate samples taken adjacent to each other and between sampling points that cannot be reasonably eliminated. Additionally, there also may be unknown geologic details that have not been identified or correctly appreciated at the current level of accumulated knowledge about our properties. This could result in uncertainties that cannot be reasonably eliminated from the process of estimating resources/reserves. If these estimates were to prove to be unreliable, we could implement an exploitation plan that may not lead to commercially viable operations in the future.

Any material changes in mineral resource/reserve estimates and grades of mineralization will affect the economic viability of placing a property into production and a property’s return on capital.

Mineral resource/reserve estimates may require adjustments or downward revisions. In addition, the grade of ore ultimately mined, if any, may differ from that indicated in the 2026 S-K 1300 Elk Creek Technical Report Summary. Minerals recovered in small scale tests may not be duplicated in large scale tests under on-site conditions or at commercial production scale.

The mineral resource and mineral reserve estimates included in the 2026 S-K 1300 Elk Creek Technical Report Summary and contained in this Annual Report on Form 10-K have been determined based on assumed future prices, cut-off grades, and operating costs that may prove to be inaccurate. Extended declines in market prices for our products may render portions of our resource/reserve estimates uneconomic and may result in reduced reported resources/reserves or may adversely affect any commercial viability determinations we may reach. Any material reductions in estimates of resources/reserves could have a material adverse effect on our Common Share price and on the value of our properties.

We face intense competition in the mining industry.

The mining industry is intensely competitive in all of its phases, and we compete with other companies for capital. In particular, the U.S. Government has made, and may continue to make, significant investments in other companies engaged in the mining of scandium, REEs, and other critical minerals, which may provide those companies with greater access to capital, resources, and operational support. As a result of this competition, some of which is with large established mining companies with substantial capabilities and with greater financial and technical resources than ours, we may be unable to obtain financing for the Elk Creek Project on terms we consider acceptable, or at all, or to acquire and develop additional properties in the future. Government investment in competing projects may also accelerate the development of alternative sources of supply for our products, which could reduce the prices we are able to realize for our products, and diminish our ability to negotiate offtake or supply agreements on favorable terms. In addition, we compete with others in efforts to obtain resources to advance the Elk Creek Project to construction and commercial operation, including mining and processing equipment, as well as qualified managerial and technical employees. If we are unable to successfully compete for required resources, including qualified employees, we may have difficulty in advancing the Elk Creek Project to construction and commercial operation. In addition, in competing for qualified personnel, we may be required to pay compensation or benefits relatively higher than those paid in the past, and the availability of qualified personnel may be limited in high-demand periods.

Changes in geopolitical conditions and U.S. critical minerals policy could reduce the strategic importance of our planned products and adversely affect our business.

A part of our business strategy is supported by the current geopolitical and national security environment, including ongoing trade tensions between the United States and China, China’s restrictions on exports of certain strategic minerals, and U.S. Government initiatives to strengthen domestic supply chains for critical minerals. These developments have increased interest in and public support for U.S.-based critical mineral projects like the Elk Creek Project.

There is no assurance that these conditions will persist or that the Elk Creek Project will benefit from this strategic focus. Certain government agencies may possess the means to finance only a limited number of critical minerals projects, which could result in fewer projects being funded and increased competition for such support. Our ability to obtain funds or incentives from U.S. Government sources is subject to the availability of funds under applicable government programs and there is no guarantee that there will be opportunities for us to receive such financing or support or that we will be successful in obtaining any grants, awards, loans, or other incentives.

Any improvement in U.S.-China relations, reduction or removal of tariffs or export controls, a shift in U.S. Government priorities regarding access to critical minerals, or identification of other readily available sources of our planned products, could decrease or eliminate the perceived strategic value of domestic production of certain strategic minerals, including scandium, dysprosium and terbium. Similarly, if China were to resume or expand exports of certain strategic minerals, including scandium, dysprosium and terbium, global supply and pricing dynamics could change materially, which could reduce the focus on developing U.S.-based projects.

In addition, U.S. Government agencies, including the DoW, may decide not to continue, or may significantly reduce efforts, to promote domestic critical minerals development. If U.S. Government interest or policy support for domestic critical mineral projects declines, our ability to secure project financing and establish the commercial viability of the Elk Creek Project could be adversely affected. Any such decline could have a material adverse effect on our business, results of operations, and financial condition.

Difficulties in water balance management at our Elk Creek Project could negatively affect our potential production and economics at the project.

The Company has conducted three field investigations and two major technical studies into the hydrogeology of the Elk Creek carbonatite, which is the geologic formation which hosts the mineralized material that would be extracted by the Company’s mining operations. The Company expects to encounter significant amounts of water in the carbonatite, which will need to be pumped out of the formation to facilitate a mining operation. Water quality analyses have demonstrated that this water will have elevated temperature and salt content when compared to other water resources in the area. While the Company has developed plans to treat water produced from the mine for use in its operations, there is no guarantee that the permits needed for the treatment of the water or the disposal of the resultant waste products will be issued by the State of Nebraska, nor is there any guarantee that such permits will be issued in a timely fashion. Further, based on such plans, the operations will rely on a water treatment system to achieve zero discharge of wastewater, and there is no guarantee that this system will function as designed or achieve nameplate treatment capacity.

Title to our properties may be subject to other claims that could affect our property rights and claims.

There are risks that title to our properties may be challenged or impugned. Our Elk Creek Project is located in Nebraska and may be subject to prior unrecorded agreements or transfers or native land claims, and title may be affected by undetected defects. The property we already own will allow us to construct the Elk Creek Project once sufficient project financing is obtained. Our current land and/or mineral rights lease agreements between ECRC and individual landowners give us an OTP, which may be used to support potential future operations, additional mineral exploration activities, and expansion. The rights of the current owners to sell the property subject to these options may be subject to prior unrecorded or unknown claims to title. Further, our current OTP agreements are of fixed duration and expire between December 2029 and May 2040, and we may incur additional cost and delays in securing renewals of such OTPs. We have investigated our rights to explore and exploit the Elk Creek Project resource/reserve and, to the best of our knowledge, our rights in relation to lands covering the Elk Creek Project resource/reserve are in good standing. However, there may be valid challenges to the title of our properties that, if successful, could impair development and/or operations.

Our properties and operations may be subject to litigation or other claims.

From time to time our properties or operations may be subject to disputes that may result in litigation or other legal claims. We may be required to assert or defend against these claims, which will divert resources and management time from operations. The costs of these claims or adverse filings may have a material effect on our business and results of operations.

We do not currently insure against all the risks and hazards of mineral exploration, development, and mining operations.

Exploration, development, mining, and surface operations involve various hazards, including environmental hazards, industrial accidents, metallurgical and other processing problems, unusual or unexpected rock formations, structural cave-ins or slides, flooding, fires, and periodic interruptions due to inclement or hazardous weather conditions. These risks could result in damage to or destruction of mineral properties, facilities, or other property, personal injury, environmental damage, delays in operations, increased cost of operations, monetary losses, and possible legal liability. We may not be able to obtain insurance to cover these risks at economically feasible premiums or at all. We may elect not to insure where premium costs are

disproportionate to our perception of the relevant risks. The payment of such insurance premiums and of such liabilities would reduce the funds available for exploration and production activities.

Risks Related to Government Regulation

We may not be able to obtain or renew all required permits and licenses to place any of our properties into production.

Our current and future operations, including development activities and commencement of production, if warranted, on the Elk Creek Project, require permits from governmental authorities and such operations are and will be governed by laws and regulations governing prospecting, development, mining, production, exports, taxes, labor standards, occupational health, waste disposal, toxic substances, land use, environmental protection, mine safety, and other matters. Companies engaged in mineral property exploration and the development or operation of mines and related facilities generally experience increased costs, as well as delays in production and other schedules as a result of the need to comply with applicable laws, regulations, and permits. We cannot predict if all permits that we may require for continued exploration, development, or construction of mining facilities and conduct of mining operations will be obtainable or renewable on reasonable terms, if at all. Costs related to applying for and obtaining permits and licenses may be prohibitive and could delay our planned exploration and development activities. Failure to comply with applicable laws, regulations, and permitting requirements may result in enforcement actions, including orders issued by regulatory or judicial authorities causing operations to cease or be curtailed, and may include corrective measures requiring capital expenditures, installation of additional equipment, or remedial actions.

Facilities associated with the Elk Creek Project, such as the mine, surface plant, tailings facilities, stockpiles and supporting infrastructure, are likely to either temporarily or permanently impact water bodies and wetlands that are subject to regulation by the USACE as Waters of the United States (“WOUS”). We believe that we have obtained the necessary USACE permits to construct the project, but changes to the design or layout of the facility may trigger the USACE to require us to obtain and maintain additional permits for the Elk Creek Project. The duration of this permitting exercise is dictated by the USACE and would need to be completed before facilities that would impact WOUS could be constructed. We may experience delays or additional costs in relation to obtaining the necessary permits and these delays and additional costs could negatively affect the economics of the Elk Creek Project and our results of operations.

Parties engaged in mining operations may be required to compensate those suffering loss or damage by reason of the mining activities and may have civil or criminal fines or penalties imposed for violations of applicable laws or regulations. Amendments to current laws, regulations, and permits governing operations and activities of mining companies, or more stringent implementation thereof, could have a material adverse impact on our operations and cause increases in capital expenditures or production costs or reduction in levels of production at producing properties or require abandonment or delays in development of new mining properties.

We are subject to significant governmental regulations that affect our operations and costs of conducting our business.

Our current and future operations, including development of the Elk Creek Project, are and will be governed by laws and regulations, including:

Companies engaged in development activities often experience increased costs and delays in production and other schedules as a result of the need to comply with applicable laws, regulations, and permits. Failure to comply with applicable laws, regulations, and permits may result in enforcement actions, including the forfeiture of mineral claims or other mineral tenures and/or orders issued by regulatory or judicial authorities requiring operations to cease or be curtailed, and may include corrective measures requiring capital expenditures, installation of additional equipment, or costly remedial actions. We may be required to compensate those suffering loss or damage by reason of our development activities and may have civil or criminal fines or penalties imposed for violations of such laws, regulations, and permits.

Existing and possible future laws, regulations, and permits governing operations and activities of mineral development companies, or more stringent implementation, could have a material adverse impact on our business and cause increases in capital expenditures or require abandonment or delays in development. Our Elk Creek Project is located in Nebraska, and while the State does have a comprehensive and modern set of environmental regulations, it does not have specific regulations with respect to permitting or reclaiming mines which could potentially impact the total time to market for the project.

Our activities are subject to environmental laws and regulations that may change, thereby increasing our costs of doing business and restricting our operations.

All phases of our operations are subject to environmental regulation in the jurisdictions in which we operate. Environmental legislation is evolving in a manner that may require stricter standards and enforcement, increased fines and penalties for non-compliance, more stringent environmental assessments of proposed projects, and a heightened degree of responsibility for companies and their officers, directors, and employees. These laws address emissions into the air, discharges into water, management of waste, management of hazardous substances, protection of natural resources, antiquities and endangered species, and reclamation of lands disturbed by mining operations. Compliance with environmental laws and regulations, and future changes in these laws and regulations, may require significant capital outlays and may cause material changes or delays in our operations and future activities. It is possible that future changes in these laws or regulations could have a significant adverse impact on our properties or some portion of our business, causing us to re-evaluate those activities at that time.

Regulations and pending legislation governing issues involving climate change could result in increased operating costs, which could have a material adverse effect on our business.

A number of governments or governmental bodies have introduced or are contemplating legislative and/or regulatory changes in response to concerns about the potential impact of climate change. Legislation and increased regulation regarding climate change could impose significant costs on us, on our future venture partners, if any, and on our suppliers, including costs related to increased energy requirements, capital equipment, environmental monitoring and reporting, and other costs necessary to comply with such regulations. Any adopted future climate change regulations could also negatively impact our ability to compete with companies situated in areas not subject to such limitations. Given the emotion, political significance, and uncertainty surrounding the impact of climate change and how it should be dealt with, we cannot predict how legislation and regulation will affect our financial condition, operating performance, and ability to compete. Furthermore, even without such regulation, increased awareness and any adverse publicity in the global marketplace about potential impacts on climate change by us or other companies in our industry could harm our reputation. The potential physical impacts of climate change on our operations are highly uncertain and could be particular to the geographic circumstances in areas in which we operate and may include changes in rainfall and storm patterns and intensities, water shortages, changing sea levels, and changing temperatures. These impacts may adversely impact the cost, production, and financial performance of our operations.

Our failure to comply with applicable anti-corruption, anti-bribery, anti-money laundering and similar laws and regulations could negatively impact our reputation and results of operations.

Our governance and compliance policies and processes may not prevent potential breaches of law or accounting or other governance practices. Our operating and ethical codes, among other standards and guidance, may not prevent instances of fraudulent behavior and dishonesty, nor guarantee compliance with legal and regulatory requirements.

We may be required to comply with anti-corruption laws and regulations imposed by governments with jurisdiction over our operations, which may include U.S. and Canadian anti-bribery and corruption legislation, as well as the laws of other countries where we do business or have a close connection. These laws and regulations may restrict our operations, trade practices, investment decisions, and partnering activities. We are subject to the jurisdiction of various governments and regulatory agencies around the world, which may bring our personnel and representatives into contact with “foreign officials” responsible for issuing or renewing permits, licenses or approvals or for enforcing other governmental regulations.

Our failure to successfully comply with these laws and regulations may expose us to reputational harm, as well as significant sanctions, including criminal fines, imprisonment, civil penalties, disgorgement of profits, injunctions, and debarment from government contracts, as well as other remedial measures. Investigations of alleged violations can be expensive and disruptive. Compliance, on the other hand, often adds cost and complexity to the permitting process and subsequent operations. There can be no guarantee that we will effectively prevent violations by our employees or business partners acting on our behalf, for which we may be held responsible, and any such violation could adversely affect our reputation, business, results of operations and financial condition.

Land reclamation requirements for our properties may be burdensome and expensive.

Although variable depending on location and the governing authority, land reclamation requirements are generally imposed on mineral exploration companies (as well as companies with mining operations) in order to minimize long-term effects of land disturbance.

Reclamation may include requirements to:

In order to carry out reclamation obligations imposed on us in connection with our potential development activities, we must allocate financial resources that might otherwise be spent on further exploration and development programs. We plan to set up a provision for our reclamation obligations on our properties, as appropriate, but this provision may not be adequate. If we are required to carry out unanticipated reclamation work, our financial position could be adversely affected.

Risks Related to Our Debt

We expect to incur substantial debt in connection with the Elk Creek Project, which will require a significant amount of cash to service, require us to comply with certain covenants and restrictions, and could impair our ability to obtain additional financing.

We expect to incur substantial debt as part of our plan to obtain project financing sufficient to cover initial capital costs and other related expenses necessary to the commencement and completion of construction of the Elk Creek Project, which may include, but is not limited to, the EXIM Financing. We currently anticipate that the upfront capital expenditure amount for the Elk Creek Project will be funded through a combination of debt and equity financing, with approximately 65% of such amount being funded from the net proceeds of debt financing. We will require a significant amount of cash to service any future debt obligations and our ability to generate cash will depend on our future operations, which are subject to prevailing industry conditions and other factors, many of which are beyond our control. We also expect that any agreements governing our future indebtedness will require us to comply with certain covenants and restrictions that limit our ability to engage in activities that may be in our long-term best interests. Any failure to comply with such covenants and restrictions could adversely affect our reputation, business, results of operations and financial condition.

In addition, our articles of incorporation do not limit the amount of indebtedness that we may incur. Any substantial indebtedness could impair our ability to obtain additional financing on a timely basis, or at all, for working capital or to take advantage of business opportunities that may arise.

Risks Related to the Common Shares

NioCorp may be a “passive foreign investment company” for the current taxable year and for one or more future taxable years, which may result in materially adverse U.S. federal income tax consequences for U.S. investors.

If NioCorp is a passive foreign investment company (“PFIC”) for any taxable year, or portion thereof, that is included in the holding period of a U.S. holder of Common Shares or other securities of NioCorp, such U.S. holder may be subject to certain adverse U.S. federal income tax consequences. These adverse tax consequences include requirements to treat any gain realized upon a disposition of Common Shares or other securities, or any “excess distribution” received on Common Shares, as ordinary income, to pay an interest charge on a portion of such gain or distribution, and certain additional reporting requirements. Such consequences may be mitigated with respect to Common Shares (but not with respect to Warrants or other securities of NioCorp) if the holder thereof makes a timely and effective “qualified electing fund” or “QEF” election or a “mark-to-market” election. A U.S. holder of Common Shares that makes a QEF election generally must include in income on a current basis for U.S. federal income tax purposes its share of NioCorp’s net capital gain and ordinary earnings for any taxable year in which it is a PFIC, whether or not NioCorp distributes any amount to its shareholders. A U.S. holder of Common Shares that makes a mark-to-market election generally must include as ordinary income each year the excess of the fair market value of the Common Shares over the taxpayer’s basis therein.

NioCorp generally will be classified as a PFIC for a taxable year if (a) 75% or more of its gross income for such year is “passive income” (generally, dividends, interest, rents, royalties, and gains from the disposition of assets producing passive income) or (b) at least 50% or more of the value of its assets produce, or are held for the production of, passive income, based on the quarterly average of the fair market value of such assets. NioCorp believes that it was classified as a PFIC for its taxable years ended June 30, 2026 and 2025 and, based on the current composition of its income and assets, as well as current business plans and financial expectations, may be classified as a PFIC for its current or future taxable years. Any conclusion regarding PFIC status is a factual determination that must be made annually at the close of each taxable year and, thus, is subject to change. In addition, even if NioCorp concluded it did not qualify as a PFIC, it is possible that the U.S. Internal Revenue Service (the “IRS”) could assert, and that a court could sustain, a determination that NioCorp is a PFIC. Accordingly, there can be no assurance that NioCorp will not be treated as a PFIC for any taxable year. The PFIC rules are complex and each holder of Common Shares or other securities of NioCorp should consult its own tax advisors regarding these rules and the U.S. federal income tax consequences of the acquisition, ownership, and disposition of such securities.

The 2023 business combination with GXII could result in NioCorp becoming subject to materially adverse U.S. federal income tax consequences.

Section 7874 and related sections of the U.S. Internal Revenue Code of 1986, as amended (the “Code”), provide for certain adverse tax consequences when the stock of a U.S. corporation is acquired by a non-U.S. corporation in certain transactions in which former shareholders of the U.S. corporation come to own 60% or more of the stock of the non-U.S. corporation (by vote or value, and applying certain specific counting and ownership rules). These adverse tax consequences include (i) potential additional required gain recognition by the U.S. corporation, (ii) treatment of certain payments to the non-U.S. corporation that reduce gross income as “base erosion payments,” (iii) an excise tax on certain options and stock-based compensation of the U.S. corporation, (iv) disallowance of “qualified dividend” treatment for distributions by the non-U.S. corporation, and (v) if former shareholders of the U.S. corporation come to own 80% or more of the stock of the non-U.S. corporation, treatment of the non-U.S. corporation as a U.S. corporation subject to U.S. federal income tax on its worldwide income (in addition to any tax imposed by non-U.S. jurisdictions). If the 2023 business combination with GXII results in the application of any of these, or any other, adverse tax consequences, NioCorp could incur significant additional tax costs. While NioCorp currently does not believe the 2023 business combination with GXII will cause such adverse tax consequences as a result of Section 7874 and related sections of the Code, this determination is subject to significant legal and factual uncertainty. NioCorp has not sought and will not seek any rulings from the IRS as to the tax treatment of the 2023 business combination with GXII or any related transactions. Further, there can be no assurance that your tax advisor, the IRS, or a court, will agree with the position that NioCorp is not subject to these adverse tax consequences.

Our Common Share price may be volatile and as a result you could lose all or part of your investment.

In addition to volatility associated with equity securities in general, the value of your investment could decline due to the impact of any of the following factors upon the market price of the Common Shares:

In particular, any material reductions in resource/reserve estimates, material increases in capital or operating costs relative to those reflected in the 2026 S-K 1300 Elk Creek Technical Report Summary, or other adverse changes to project economics could have a material adverse effect on the value of our properties and the market price of our Common Shares. See “We face numerous uncertainties in estimating our mineral reserves and resources and inaccuracies in our estimates could result in lower than expected revenues, higher than expected costs, and decreased profitability” in Item 1A., Risk Factors above.

From July 1, 2025, to the date of this report, the trading price of our stock on the Nasdaq has ranged from a low of $2.19 to a high of $11.67.

In addition, stock markets in general have experienced extreme price and volume fluctuations, and the market prices of securities have been highly volatile. These fluctuations are often unrelated to operating performance and may adversely affect the market price of the Common Shares. As a result, you may be unable to sell any Common Shares you acquire at a desired price.

We have never paid dividends on the Common Shares.

We have not paid dividends on the Common Shares to date, and we may not be in a position to pay dividends for the foreseeable future. Our ability to pay dividends with respect to the Common Shares will depend on our ability to successfully develop one or more properties and generate earnings from operations. Further, our initial earnings, if any, will likely be retained to finance our operations. Any future dividends on Common Shares will depend upon our earnings, our then-existing financial requirements, and other factors, and will be at the discretion of our Board.

Future sales, or the perception of future sales, of Common Shares by existing shareholders or by us, or future dilutive issuances of Common Shares by us, or future exercises or exchanges of outstanding Warrants or securities exchangeable for Common Shares, could adversely affect prevailing market prices for the Common Shares and cause investors to suffer dilution in their net book value per Common Share.

In addition to potential debt financing, our plan to obtain project financing sufficient to cover initial capital costs and other related expenses necessary to the commencement and completion of construction of the Elk Creek Project includes the sale and issuance of equity securities which may include, but is not limited to, Common Shares, Warrants, or pre-funded Warrants. Sales of a substantial number of Common Shares in the public market could occur at any time, including issuances and sales of additional Common Shares by us and sales by other security holders. These sales, or the market perception that the holders of a large number of Common Shares or securities convertible, exercisable, or exchangeable into Common Shares intend to sell Common Shares, could reduce the prevailing market price of the Common Shares. The effect, if any, that future public sales of these securities or the availability of these securities for sale will have on the market price of the Common Shares is uncertain. If the market price of the Common Shares were to drop as a result, this might impede our ability to raise additional capital and might cause remaining shareholders to lose all or part of their investment.

The Articles of NioCorp, as amended, permit us to issue an unlimited number of Common Shares. Subject to the requirements of the British Columbia Business Corporations Act and Nasdaq, we will not be required to obtain the approval of the NioCorp shareholders for the issuance of additional Common Shares. We have issued Common Shares in the past and intend to continue to issue Common Shares to finance our activities in the future. In addition, outstanding Options and Warrants and securities convertible into or exchangeable for Common Shares may be exercised, converted, or exchanged resulting in the issuance of additional Common Shares. If we issue additional Common Shares or decide to enter into joint ventures with other parties in order to raise financing through the sale of equity securities, investors’ interests in the Company will be diluted and investors may suffer dilution in their net book value per Common Share depending on the price at which such securities are sold.

We are subject to the continued listing criteria of the Nasdaq and our failure to satisfy these criteria may result in delisting of the Common Shares.

Our Common Shares are currently listed on the Nasdaq under the symbol “NB”. The public NioCorp Assumed Warrants are currently listed on Nasdaq under the symbol “NIOBW.” The Nasdaq has rules for continued listing. In order to maintain the listings, we must maintain certain financial and share distribution targets, including maintaining a minimum number of public shareholders.

If Nasdaq delists the Common Shares, investors may face material adverse consequences, including, but not limited to, a lack of a trading market for the Common Shares, reduced liquidity, a determination that our Common Shares are a “penny stock,” decreased analyst coverage of the Company, and an inability for us to obtain additional financing to fund our operations.

Our Rights Plan includes terms and conditions that could discourage a take-over or other transaction that shareholders may consider favorable.

On November 21, 2025, the Company adopted the Rights Plan pursuant to the Original Rights Plan Agreement, between the Company and the Rights Agent. One Right was issued for each Common Share outstanding as of December 4, 2025, and a Right automatically attaches to each Common Share subsequently issued until the expiration of the Rights Plan. The Rights generally become exercisable only if a person or group acquires, or announces the current intention of commencing a take-over bid to acquire, beneficial ownership of 20% or more of the Company's outstanding Common Shares, other than through a permitted bid made in compliance with applicable Canadian take-over bid rules. If the Rights become exercisable, each holder of a Right, other than the acquiring person, would be entitled to purchase additional Common Shares at a discount to the then-current market price.

On April 6, 2026, following approval by the Company's shareholders at the Company's annual general meeting held on April 6, 2026, the Company and the Rights Agent entered into the Amended Rights Plan Agreement, which amended and restated the Original Rights Plan Agreement in its entirety. Under the Original Rights Plan Agreement, the Rights Plan would have expired on May 21, 2026. Under the Amended Rights Plan Agreement, the Rights Plan now expires at 5:00 p.m. (Toronto time) on the date of the Company's next annual general meeting.

The Board adopted the Rights Plan to help ensure that all shareholders of the Company are treated equally and fairly in the event of any unsolicited take-over bid or other attempt to acquire control of the Company (including by way of a “creeping take-over bid”). The Rights Plan was not adopted in response to any specific take-over bid or other proposal to acquire control of the Company.

The Rights Plan will cause substantial dilution to any person, entity or group that acquires beneficial ownership of 20% or more of the outstanding Common Shares. As a result, the overall effect of the Rights Plan and the issuance of the Rights may be to discourage any person, entity or group from gaining a control or control-like position in the Company or engaging in other tactics, potentially disadvantaging the interests of the Company’s shareholders, without negotiating with the Board and without paying an appropriate control premium to all shareholders. The Rights Plan is intended to, among other things, (i) encourage potential bidders to treat the Company’s shareholders fairly and equally and preserve control premiums and value for shareholders and (ii) provide the Board and shareholders adequate time to appropriately respond on an informed basis. Nevertheless, the Rights Plan may be considered to have certain anti-take-over effects, including potentially discouraging a third party from attempting to obtain a substantial position in the Common Shares or seeking to obtain control of the Company and discouraging a take-over attempt that shareholders may consider favorable or that could result in a premium over the market price of the Common Shares. Even in the absence of a take-over attempt, the Rights Plan may adversely affect the prevailing market price of Common Shares if it is viewed as discouraging take-over attempts in the future.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

ITEM 1C. CYBERSECURITY

ITEM 2. PROPERTIES

Elk Creek Project, Nebraska

Our principal mineral property is the Elk Creek Property, a development stage property that is expected to produce eight commercial mineral products: ferroniobium, scandium oxide, titanium tetrachloride, neodymium-praseodymium (“NdPr”) oxide, dysprosium oxide, terbium (“Tb”) oxide, SEG carbonate, and heavy rare earth ("heavies") carbonate. As discussed in greater detail below, the Elk Creek Project has established measured, indicated, and inferred resources along with proven and probable reserves. The below information is in part summarized or extracted from our 2026 S-K 1300 Elk Creek Technical Report Summary, which is filed as Exhibit 96.1 to this Annual Report on Form 10-K. The 2026 S-K 1300 Elk Creek Technical Report Summary has an overall effective date of June 30, 2026. The Company does not have any other material properties.

The qualified persons responsible for the 2026 S-K 1300 Elk Creek Technical Report Summary are:

A table of the sections for which each qualified person is responsible is included in Section 2.6 of the 2026 S-K 1300 Elk Creek Technical Report Summary. Except for Scott Honan, none of the qualified persons is affiliated with the Company. Mr. Honan is the Chief Operating Officer of the Company. The disclosure of scientific or technical information in this Annual Report on Form 10-K was reviewed and approved by Mr. Honan who is a qualified person as defined in NI 43-101, and Mr. Honan has verified the data disclosed herein.

The 2026 S-K 1300 Elk Creek Technical Report Summary summarizes the 2026 Elk Creek Study, which, among other matters, updates the Elk Creek Project’s economics to incorporate the expanded product offering, including REEs, revises mine and processing design, and updates mineral resource and mineral reserve estimates and current capital and operating cost estimates. The 2026 Elk Creek Study comprises the results of the technical and economic analyses conducted by the qualified persons, which were also presented in the 2026 NI 43-101 Elk Creek Technical Report. The 2026 Elk Creek Study qualifies as a feasibility study within the meaning given to such term under the CIM Definition Standards (2014) for purposes of NI 43-101 and qualifies as a pre-feasibility study within the meaning given to such term under S-K 1300. The reason that the 2026 Elk Creek Study does not qualify as a feasibility study under S-K 1300 is because additional work with respect to the engineering of and procurement for the planned surface plant is required to allow the qualified person to reduce the overall contingency range attributed to the initial capital expenditure estimate for the Elk Creek Project from the current 14% to less than or equal to 10%. Even as additional work is completed and the contingency range is reduced, accordingly, there can be no assurance that the actual initial capital expenditure requirements will not materially exceed estimates.

Property Description and Location

The Elk Creek Property consists of certain interests of NioCorp in land and mineral rights located in Johnson and Pawnee Counties, southeast Nebraska, USA. The carbonatite contains elements of economic significance, including niobium, titanium, and scandium, as well as several REEs. The Elk Creek Property is situated as shown below and is located within the USGS Tecumseh Quadrangle Nebraska SE (7.5 minute series) mapsheet in Sections 1-6, 9-11; Township 3N; Range 11E and Sections 19-23, 25-36; Township 4N, Range 11E, at approximately 40°16’ north and 96°11’ west in the State of Nebraska, in central USA. The Elk Creek Property is approximately 47 miles southeast of Lincoln, Nebraska, the state capital of Nebraska.

Title and Ownership

Land in the project area is exclusively owned by private entities, and there is no federal or state land in the project area. The Company has secured its rights to the project area by purchasing land from private landowners or by entering into agreements with the landowners as described below.

Following the acquisition of an additional approximately 447 acres of land pursuant to existing OTPs during fiscal year 2026, the Company, through its subsidiary ECRC, owns the surface rights and/or mineral rights to approximately 710 acres of land in and around the project area. This includes an approximately one-square-mile (approximately 630-acre) section of which it owns the mineral rights to all but approximately 80 acres and all of the surface rights, all within the carbonatite footprint. The Elk Creek Project’s mine infrastructure and a portion of the supporting operations is planned to be located within this section. Ownership of the mineral rights in this section includes a 2% NSR royalty and grants us access to all of the Elk Creek Project’s mineral resources and mineral reserves.

The land owned by ECRC currently houses the Company’s drill core inventory and geological sample repository in two steel core shed buildings, and the Company maintains vegetative cover on portions of the property that were formerly used for growing row crops. Additionally, the Company has begun construction of the main access, known as a “portal,” to the underground portion of the Elk Creek Project on the land owned by ECRC. The portal will serve as the primary access point for personnel, equipment, and materials, as well as to deliver ore from the underground mine to the surface production plant.

As of June 30, 2026, the total book value of the Elk Creek Property and associated buildings and equipment was approximately $37.3 million.

The Company also currently holds six OTPs that are associated with the Elk Creek Project and one perpetual easement on a land parcel adjacent to the Missouri River. The current optioned land package covers an area of approximately 1,011 acres and includes the land needed for the development of tailings storage facilities that are expected to be developed in phases over the Elk Creek Project’s proposed 40-year operating life. Details on the current OTPs held by the Company are shown in the table below.

Active Lease Agreements (OTPs) Covering the Elk Creek Project as of September 2026

The OTPs are between NioCorp’s subsidiary ECRC and the individual landowners. Land subject to the OTP agreements is currently used for agricultural purposes, including growing row crops (corn and soybeans) and pasturing livestock. The OTPs grant the Company an exclusive right to explore and evaluate the property during the term thereof, with an option to purchase the surface rights or a combination of the mineral and surface rights at any time during the term. The OTPs that involve mineral rights provide for a 2% NSR royalty.

In general, exercise of an OTP is accomplished by paying the greater of a fixed amount per acre or a multiple of the appraised value at the time of purchase. If the land is not purchased by the Company during the term of the OTP and the land in question is needed for the Elk Creek Project, the Company intends to negotiate a new OTP with the landowner. Each OTP is accompanied by a negotiated payment to the landowner that is paid upon execution of the OTP by the Company and the landowner. As of June 30, 2026, the Company was obligated to make payments totaling approximately $48 over the next 9 years to maintain our rights under these OTPs.

Land Tenure Map as of September 2026

Accessibility, Climate, Local Resources, Infrastructure and Physiography

The Elk Creek Property is easily accessible year-round as it is situated approximately 47 miles southeast of Lincoln, Nebraska, the state capital, and approximately 68 miles south of Omaha, Nebraska. Access to the site can be completed via interstates and state highways or from one of the regional airports. There are several regularly scheduled flights to both Lincoln and Omaha, with Omaha providing more regular commercially serviced options. From Eppley Airfield in Omaha, Nebraska, the Elk Creek Property is accessed via paved roads on the main network. The section in which the Company plans to construct both the underground critical minerals mine and integrated surface processing facility associated with the Elk Creek Project, and where the mineral resource and mineral reserve are centered, is in Section 33, Township 4N, Range 11E within the USGS Tecumseh Quadrangle Nebraska SE (7.5 minute series) mapsheet. This section is immediately southwest of the junction of Nebraska state highways 50 and 62, which turns into county road 721 west of state highway 50. The Elk Creek Project will be accessed from the north from county road 721. A secondary access point is available on the east side of the project from state highway 50. Rail access is available in the town of Elk Creek, which is located 3 miles east of the project area.

Southeast Nebraska is situated in a humid continental climate (Dfa) on the Köppen climate classification system. In eastern Nebraska, this climate is generally characterized by hot, humid summers and cold winters. Average winter temperatures vary between 13°F to 35°F. Average summer temperatures vary between 65°F to 88°F. Exploration and mining-related activities may be conducted all year round although severe winter weather and spring/early-summer thunderstorm activity can periodically affect operations.

Average monthly precipitation (rain and liquid-equivalent snowfall) varies between 0.8 and 5.3 inches, with a mean annual total of approximately 32.3 inches. Average snowfall is approximately 22 inches. Nebraska is located within a region of the central United States that experiences severe thunderstorms and tornadoes, with peak tornado occurrence generally during May through July, although events can occur outside this period.

The area is well developed with direct access to roads, rail, supply and distribution companies, and a local workforce, including heavy equipment operators. There are several local communities near the Elk Creek Property, including Elk Creek, Syracuse, Tecumseh and Pawnee City, that are capable of providing local housing for the Elk Creek Project construction and operating staff. There are several other communities within driving distance and the large cities of Lincoln and Omaha are also within reasonable driving distance. Both cities have substantial regional airports.

The Elk Creek Project is expected to incorporate surface and underground infrastructure, as well as surface tailings and salt storage facilities. The offsite infrastructure is expected to include a water supply pipeline from the City of Tecumseh and temporary and permanent natural gas pipelines. On-site power is expected to be provided by a third-party microgrid using modular 2.5 megawatts ("MW") natural gas generators, rated at approximately 50 MW. Initially, a 15 MW construction microgrid is expected to be supplied, with gas from trucked liquefied natural gas and/or a temporary pipeline connection approximately 5 miles east. A permanent gas pipeline from a main distribution line approximately 30 miles west is expected to be connected around the end of the second construction year. Before the end of construction, the larger 50 MW microgrid is expected to replace the construction microgrid. Approximately 200 kilowatts ("kW") of grid power from the local power utility is also expected to be utilized via an existing connection. Water used for all on-site process needs and activities is expected to be supplied from mine dewatering activities, recycling, and from a local water utility. See “Planned Operations” below for additional information regarding proposed infrastructure related to the Elk Creek Project.

The local topography of eastern Nebraska is relatively low-relief with shallow rolling hills intersected by shallow river valleys. Elevation varies from about 1,066 feet ("ft") to 1,276 ft above mean sea level. Bedrock outcrop exposure is nonexistent in the Elk Creek Project area.

The majority of the area around the Elk Creek Project is used for cultivation of corn and soybeans, along with uses as grazing land. Native vegetation typical of eastern Nebraska is upland tall-grass, prairie and upland deciduous forests.

Geology and Mineralization

Geology

The Elk Creek Property includes a carbonatite that has intruded older Precambrian granitic and low- to medium-grade metamorphic basement rocks. The carbonatite is an elliptical magmatic body with a northwest-trending long axis perpendicular to the strike of the Midcontinent Rift System, near the northern part of the Nemaha uplift. The carbonatite consists predominantly of dolomite, calcite and ankerite, with lesser chlorite, barite, phlogopite, pyrochlore, serpentine, fluorite, sulfides and quartz. It is, however, believed from stratigraphic reconstruction based on drill core observation in the area that the carbonatite is unconformably overlain by approximately 656 ft of essentially flat-lying Paleozoic marine sedimentary rocks, including carbonates, sandstones and shales of Pennsylvanian age.

Mineralization

The property hosts niobium, titanium, and scandium mineralization as well as REE mineralization that occurs within the Elk Creek carbonatite. The current extent of modeled mineralization is 3,937 ft (1,200 meters ("m")) along strike, 1,640 ft (500 m) wide, and 2,461 ft (750 m) in dip extent below the unconformity. Niobium, titanium, scandium, and rare earth elements are considered the main elements of interest.

The deposit contains significant concentrations of niobium. Based on the metallurgical test work completed to date at several laboratories using QEMSCAN® analysis, the niobium mineralization is known to be fine grained, and that 77% of the niobium occurs in the mineral pyrochlore, while the balance occurs in an iron-titanium-niobium oxide mineral of varying composition.

Within the Elk Creek carbonatite, a host of other elements exist with varying degrees of concentration. The Company has completed both whole rock analysis and multi-element analysis on all samples for the 2014 drilling program, described below, plus resampling of selected historical core/pulps between 2011 and 2021.

Historical Exploration

Drilling at the Elk Creek Property has been conducted in four phases. The first was during the 1970’s and 1980’s by the Molybdenum Company of America (“Molycorp”), the second in 2011 by Quantum Rare Earth Developments Corp (“Quantum” - NioCorp under its former name), the third in 2014 and 2015 by NioCorp and the fourth and latest program in 2025 by NioCorp. To date, 94 drill holes have been completed on the section in which NioCorp plans to construct both the underground critical minerals mine and integrated surface processing facility associated with the Elk Creek Project for a total of 196,114 ft (59,775 m), including 16 drill holes totaling 37,861 ft (11,540 m) completed in 2025. A further five holes totaling 11,001 ft (3,353.1 m) were drilled in 2015 for hydrogeological and geotechnical studies but were not used for resource estimation.

All drilling has been completed using a combination of Tricone, Reverse Circulation (“RC”) or diamond drilling in the upper portion of the hole within the Pennsylvanian sediments. A portion of the 2014 drill holes used RC drilling within the Pennsylvanian sediments to increase drilling efficiency through cover material within areas of strong geological confidence. All drilling within the underlying carbonatite has been completed using diamond drilling methods.

Summary of Drilling Database within Elk Creek Deposit Area

Exploration History

Private mineral leasing and exploration began in the early 1970s at the Elk Creek Property. Cominco American Inc. acquired mineral rights in 1973 and undertook exploration work, after which the rights were acquired by Molycorp in 1974. Molycorp completed detailed aeromagnetic surveying in 1973 and, in 1980, carried out a regional exploration program including gravity work, magnetic surveying, geologic mapping, surface sampling, and drilling. Between 1973 and 1986, Molycorp completed a regional drill program over an approximately 7 kilometers ("km") × 7 km gravity anomaly, totaling 114 drill holes for approximately 157,992 ft (48,156 m). Within the Elk Creek Deposit area, 27 holes totaling 52,848 ft (16,108 m) were drilled during the 1970–1980 period, forming the foundation of the historical drilling database.

No known exploration was completed on the Elk Creek Property between 1986 and 2011. In 2010–2011, Quantum initiated verification and modernization of the historical dataset through Dahrouge Geological Consulting Ltd., compiling and checking historical drilling, lithology, and assay information, and completing resampling of historical material to assess comparability with historical results. Quantum then completed a 2011 diamond drilling program consisting of five inclined holes totaling 11,220 ft (3,420 m) of HQ core; three holes 7,605 ft (2,318 m) targeted the Elk Creek deposit and two holes tested regional REE targets. These holes were not used for mineral resource estimation.

Following the acquisition of the Elk Creek Property, NioCorp advanced the Elk Creek Project through additional diamond drilling programs to improve confidence and support updated technical studies. Between 2014 and 2015 NioCorp drilled a total of 24 holes within the Elk Creek Deposit totaling approximately 63,390 ft (19,321 m). The program included data validation, metallurgical and mineralogical studies, geotechnical and hydrogeological studies all in support of resource estimation.

During fiscal year 2022, NioCorp collected a total of 1,095 samples originating from 18 diamond drill holes completed by Molycorp, as discussed above. These samples were collected, and subsequently assayed, in order to fill in gaps in our records regarding REE grades and tonnage that may exist in the deposit. Assaying was conducted at Activation Laboratories (“ActLabs”) in Ancaster, Ontario. The assay results were subjected to a Quality Assurance and Quality Control (“QA/QC”) program consistent with industry best practices.

During fiscal year 2026, NioCorp completed its previously announced drilling program at the Elk Creek Project (the “2025 Drilling Program”). The 2025 Drilling Program was specifically designed to target gaps within the mineral resource in support of converting a portion of the mineral resource from indicated and inferred to measured, indicated and inferred. During this campaign a total of 16 HQ diamond drillholes were completed totaling 37,861 ft (11,540 m). Assay results from the 2025 Drilling Program were added to the existing assay database and were used in the mineral resource estimate described below.

Samples from the 2025 Drilling Program were prepared and analyzed by SGS North America in Lakefield, ON. Selected pulp duplicates were submitted to ActLabs for external check analysis, with a total of 490 external pulps analyzed to test for laboratory bias. Both laboratories’ procedures were consistent with previous drilling and sampling programs.

Internal Controls

NioCorp integrated a series of routine QA/QC procedures throughout the sampling and analysis portion of the drilling programs to ensure the highest level of quality was maintained throughout the process leading to the estimate of mineral reserves and mineral resources for the Elk Creek Project. This included the insertion of duplicate samples taken from various stages of the process, insertion of known control samples (standard reference materials, certified reference materials (“CRM”), and blanks) and sending third-party pulps to a secondary lab.

To meet planned QA/QC insertion rates, the following guidelines were followed:

Additional details on the QA/QC program can be found in Section 8 of the 2026 S-K 1300 Elk Creek Technical Report Summary.

Mineral deposits, including the Elk Creek deposit, are inherently uncertain because of variability at all scales and sparse sampling. In addition to uncertainty associated with estimation, there are specific risks and sources of uncertainty associated with the Elk Creek deposit. See Item 1A., Risk Factors.

S-K 1300 and other similarly purposed International Codes (JORC, 2012; NI 43-101, 2014) are designed to require disclosure to the public of risks relating to mineral resource and reserve estimation as identified and evaluated by a qualified person. The qualified persons responsible for the 2026 S-K 1300 Elk Creek Technical Report Summary address the technical risks in various sections and identify the principal sources of uncertainty as geological confidence at depth and along the margins of the peripheral carbonatite domain, the size of the inferred mineral resource relative to the measured and indicated mineral resources, and the sensitivity of the NSR cut-off to metallurgical recovery and to commodity prices, particularly niobium and scandium. Additional descriptions of the risks and uncertainty associated with reported mineral reserves and resources can be found in Section 11 of the 2026 S-K 1300 Elk Creek Technical Report Summary.

Economic Analysis Included in the 2026 S-K 1300 Elk Creek Technical Report Summary

The metrics reported in the 2026 S-K 1300 Elk Creek Technical Report Summary are based on the cash flow model results. The metrics are on both a pre-tax and after-tax basis, on a 100% equity basis with no Elk Creek Project financing inputs and are in first quarter 2027 U.S. constant dollars. Key criteria used in the analysis are discussed in detail throughout this section.

Principal Project Assumptions

Summary of Key Evaluation Metrics

The following table sets forth mine and process plant production estimates for the Elk Creek Project over the 40-year operating life of the mine. Ore mined and ore processed refer to proven and probable mineral reserves.

Summary Pricing Assumptions

The following table sets forth applicable benchmark product pricing assumptions used in the economic analysis. Except with respect to scandium trioxide, the economic analysis assumes constant prices with no inflationary adjustments. The realized pricing used in the economic analysis was based on a combination of third-party market studies, qualified person judgment, and management expertise to establish appropriate market pricing projections. The planned products of the Elk Creek Project, especially niobium and Sc2O3, are thinly traded without an established publicly available price discovery mechanism. Hence, detailed third-party market studies were completed for all four of the major product groups that are expected to be produced from the Elk Creek Project: niobium, titanium, scandium and rare earths. These market studies analyzed relevant factors, including supply and demand trends, in order to forecast market pricing. For scandium and the heavy rare earths dysprosium and terbium, for example, the relevant market studies describe a bifurcated market between China and the rest of the world as a result of export controls implemented by China, which has resulted in prices outside of China to be significantly higher than prices within China. In the judgment of the qualified person, various assumptions were applied to the forecasted market pricing to arrive at the realized pricing used in the economic analysis, including, without limitation, terms of the offtake arrangements pursuant to which NioCorp expects to sell its products. Refer to Sections 16 and 19 of the 2026 S-K 1300 Elk Creek Technical Report Summary for additional information regarding market and netback pricing assumptions for each product.

Capital Cost Estimates

The following table shows the breakout in LoM initial capital and sustaining capital cost estimates (including closure and reclamation of $96 million), which total $4,019 million. This includes a total initial capital cost of $1,849 million, including a $233 million contingency, equal to an overall contingency of 14% on initial capital.

Totals may not sum due to rounding.

Operating Cost Estimates

The following LoM unit operating cost estimates include the pre-production and first/last years of production.

Totals may not sum due to rounding.

Summary Projected Economic Results

Totals may not sum due to rounding.

Planned Operations

Planned Mining Operations

The Elk Creek Project is planned as an underground mining operation using a long-hole stoping mining method and paste backfill, with ramp access from the surface. The mine will utilize jumbo drills for lateral development and tophammer and down-the-hole drills for vertical development and production stoping. Rock bolters will be used for ground support and probe holes will be used to support mine grouting where required. Ore will be remotely mucked from the bottom stope accesses using 10.3 cubic yard (7.9 cubic meter) battery-electric load-haul-dump units with an 18 metric tonne ("tonne") (19.8 ton) payload capacity and remote-operation capability. Ore will be transported to ore passes equipped with grizzly screens. The ore passes will report to the bottom of each of three mining horizons where the ore will be loaded on to the Railveyor system for transport to the surface plant. The Railveyor is a series of connected ore cars mounted on a rail system that move ore and waste rock from three loading stations underground to two stockpiles on the surface.

Planned Processing Operations

Planned ore processing operations include mineral processing, hydrometallurgical processing (“Hydromet”), and pyrometallurgical processing (“Pyromet”) housed in separate buildings.

The mineral processing building will house all of its equipment within a single large building. Ore from the Primary Crusher (located adjacent to the mineral processing plant on the surface) will be fed to the secondary cone crusher system, operating in closed circuit with a double deck screen. The screen undersize from the cone crusher system will be fed to a high-pressure grinding roll unit (“HPGR”), operating in closed circuit with another double deck screen. The HPGR screen undersize is the comminution product that will report to the Hydromet process.

The Hydromet plant building will be a multi-level engineered steel structure, which will house equipment on two levels. Ore from mineral processing will be fed through a series of processes required to separate the niobium, scandium, titanium and rare earths from the rest of the ore. Outputs from the Hydromet process include saleable TiCl4 and Sc2O3 along with five rare earth oxide/carbonate products, with Nb2O5 reporting to the Pyromet plant for final processing. The Hydromet plant will be supported by a hydrochloric acid regeneration operation.

The Pyromet building will house its equipment within a single building. The purpose of the Pyromet plant is to reduce the Nb2O5 coming from the Hydromet plant by converting it into a saleable FeNb metal. Aluminum shots and iron oxide pellets will be introduced to an electric arc furnace on a continuous basis along with fluxing agents and Nb2O5 to produce a saleable ferroniobium metal.

Proposed Production Plan and Schedule

Based on the 2026 S-K 1300 Elk Creek Technical Report Summary, the operating mine life is approximately 40 years with a nominal processing rate of 3,047 tons per day. The Elk Creek Project timeline is based on 30 months to mechanical completion after authorization to proceed, plus an additional five months of commissioning and ramp-up to 100% of production capacity for a total of 35 months and assumes no financing constraints. The Board must approve a construction program and budget before construction of the Elk Creek Project can begin. This approval, along with the receipt of all required governmental permits and approvals and the completion of project financing, will determine whether and when construction of the Elk Creek Project can begin.

Proposed Tailings Storage

The tailings produced by the process plant will consist of calcium carbonate, magnesium carbonate, iron oxide, leach residue, gypsum, and slag. Six engineered and lined tailings storage facilities (“TSFs”) will be constructed sequentially to contain the tailings over the life of the Elk Creek Project and have a design capacity of approximately 33.7 million tonnes, against a required capacity over the life of the Elk Creek Project of approximately 31 million tonnes. A composite lining system with leak detection and monitoring systems will be installed in each tailings impoundment.

Tailings will be delivered to the TSFs from the paste tailings plant as paste containing low quantities of binder (cement and flyash) to limit seepage. Facility closure is considered in the design.

Proposed Salt Management

The crystalline salt produced as a waste product of heating and evaporating brine from the reverse osmosis (“RO”) water treatment plant will be transported to a dedicated salt management cell. A single lined surface impoundment, which will also serve as the mine water holding pond during construction, will be constructed to contain the salt over the life of the project and is designed with a volume of approximately 16 million cubic feet. Based on expected flows, the cell is expected to reach its nominal storage capacity, inclusive of a 15% safety factor, in approximately 15 years. NioCorp expects to reduce and reuse salt from the wastewater treatment process and to contract with local landfills to accept a portion of this waste as needed. The cell will incorporate a synthetic liner meeting the requirements of Nebraska Title 123 governing the design, operation and maintenance of wastewater works.

Proposed Water Management

For the first several years of construction, the advancement of the underground workings will require limited dewatering, anticipated to be through lower-level sumping and pumping for surface collection and disposal. Formation water produced during construction is expected to be brackish and unsuitable for direct discharge and will be stored in the lined salt management cell or trucked off-site for treatment at a local publicly owned treatment works. Excess water in the salt management cell will be spray evaporated within its footprint using turbomister spray evaporators, to avoid the reintroduction of soluble salts into the water treatment system. Temporary on-site storage or off-site shipment and disposal of the crystallized solid waste may be necessary until construction of the salt management cell is completed.

Once full operations commence, a shortfall of approximately 1,000 gallons per minute of operational and processing water is anticipated. To make up this shortfall, NioCorp would purchase fresh water from a local utility and from local landowners.

Once tailings begin being deposited in the TSF, internal contact water (from residual moisture in the tailings and precipitation falling within the impoundment footprint) will need to be actively managed. This water will be collected and treated using lime softening to precipitate hydroxide and carbonate solid forms for many of the inorganic constituents. The treated water will be filtered to remove the solids (which will be returned to the TSF for disposal), and the clean water will be pumped to the process plant RO system for further treatment. The clean water from the process plant RO unit will be used in the process plant, and the reject concentrate will be crystallized and deposited into the salt management cell.

Proposed Source of Power

On-site power will be provided by a third-party microgrid based off modular 2.5 MW natural gas fired generators, rated at approximately 50 MW. A small amount of grid power (200 kW) will also be used.

Proposed Source of Natural Gas

Natural gas, to be used throughout the Elk Creek Project during the construction and operation phases of the project, will be brought to the site via pipeline from the local gas utilities. NioCorp will connect to existing distribution pipelines located 5 miles east and approximately 30 miles west of the project site. Natural gas will be distributed to all on-site facilities utilizing buried high-density polyethylene natural gas distribution pipe. Natural gas piping above ground and located inside of the facilities will consist predominately of carbon steel pipe. Natural gas will be used for power generation, facility heating, water heating, and for gas-fired process equipment.

Environmental, Permitting, and Social

The current mine design incorporates the following strategies and technologies designed to minimize environmental impacts of operation:

A number of key permits and environmental management requirements have been identified for the Elk Creek Project, some of which need to be implemented as soon as practicable in order to maintain the proposed Elk Creek Project schedule.