Approximate date of commencement of proposed sale to the public: From time to time after the effectiveness of this registration statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box: ¨

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box: x

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ¨

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ¨

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 pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

We may offer and sell, from time to time, common shares, without par value (“Common Shares”), or Common Share purchase warrants (“Warrants”), as well as units that include any of these securities, or any combination thereof. We may sell any combination of these securities in one or more offerings with an aggregate offering price of up to $200,000,000.

This prospectus describes the general manner in which the securities listed above may be offered and sold. The specific manner in which such securities may be offered and sold will be described in one or more prospectus supplements. You should carefully read this prospectus and any accompanying prospectus supplement, together with the documents we incorporate by reference, before you invest in our securities.

We may sell securities directly or to or through underwriters or dealers, and also to other purchasers or through agents. The names of any underwriters or agents that are included in a sale of such securities to you, and any applicable commissions or discounts, will be stated in an accompanying prospectus supplement.

Our Common Shares trade on The Nasdaq Global Market under the symbol “NB.” On June 12, 2024, the last reported sale price of our Common Shares on The Nasdaq Global Market was $2.14 per Common Share.

Investing in our securities involves a high degree of risk. See “Risk Factors” beginning on page 2 of this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the “SEC”) using a “shelf” registration process. The Company may offer and sell from time to time any combination of the securities described in this prospectus in one or more offerings in amounts, at prices and on terms that we determine at the time of the offering, with an aggregate offering price of up to $200,000,000. This prospectus provides you with a general description of the securities we may offer. Each time we offer securities under this prospectus, we will provide a prospectus supplement that will contain specific information about the type or series of securities offered and the terms of that offering.

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

You should rely only on the information provided in this prospectus, as well as the information incorporated by reference into this prospectus and any applicable prospectus supplement. We have not authorized anyone to provide you with different information. We have not authorized anyone to provide you with any information or to make any representations other than those contained in this prospectus or any applicable prospectus supplement or any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We do not take responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. You should not assume that the information in this prospectus or any applicable prospectus supplement is accurate as of any date other than the date of the applicable document. Since the date of this prospectus and the documents incorporated by reference into this prospectus, our business, financial condition, results of operations and prospects may have changed. We will not make an offer to sell these securities in any jurisdiction where the offer or sale is not permitted.

We may also provide a prospectus supplement or post-effective amendment to the registration statement of which this prospectus is a part to add information to, or update or change information contained in, this prospectus and the registration statement of which this prospectus is a part. You should read this prospectus and any applicable prospectus supplement or post-effective amendment to the registration statement of which this prospectus is a part together with the additional information to which we refer you in the sections of this prospectus entitled “Where You Can Find More Information” and “Information Incorporated by Reference.”

Unless we state otherwise or the context otherwise requires, the terms “we,” “us,” “our,” “our business” “NioCorp,” “the Company” and similar references refer to NioCorp Developments Ltd. and its consolidated subsidiaries.

Unless we state otherwise or the context otherwise requires, the term “ECRC” refers to Elk Creek Resources Corp. (formerly known as GX Acquisition Corp. II), a Delaware corporation and a majority-owned subsidiary of NioCorp, as the surviving entity of the mergers that occurred on March 17, 2023, as part of the Transactions (as defined herein), and the term “GXII” refers to GX Acquisition Corp. II, a Delaware corporation, as it existed prior to the closing of the Transactions.

This prospectus contains our registered and unregistered trademarks and service marks, as well as trademarks and service marks of third parties. Solely for convenience, these trademarks and service marks are referenced without the ®, ™ or similar symbols, but such references are not intended to indicate, in anyway, that we will not assert, to the fullest extent under applicable law, our rights to these trademarks and service marks. All brand names, trademarks and service marks appearing in this prospectus are the property of their respective holders.

This prospectus is part of a registration statement on Form S-3 that we filed with the SEC under the Securities Act of 1933 (the “Securities Act”) and does not contain all the information set forth or incorporated by reference in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement of which this prospectus is a part or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. You may obtain copies of the registration statement and its exhibits via the SEC’s EDGAR database.

We file annual, quarterly and current reports, proxy statements and other information with the SEC under the Securities Exchange Act of 1934 (the “Exchange Act”). The SEC maintains a website that contains reports, proxy and information statements and other information regarding issuers, including us, that file electronically with the SEC. You may obtain documents that we file with the SEC at www.sec.gov.

We make available, free of charge, on our website at www.niocorp.com, our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, proxy statements and amendments to those reports and statements as soon as reasonably practicable after they are filed with the SEC. We do not incorporate the information on or accessible through any website into this prospectus or any prospectus supplement, and you should not consider any information on, or that can be accessed through, any website as part of this prospectus or any prospectus supplement (other than those filings with the SEC that we specifically incorporate by reference into this prospectus or any prospectus supplement). Our website address and the SEC’s website address are included in this prospectus as inactive textual references only.

SEC rules permit us to incorporate information by reference into this prospectus and any applicable prospectus supplement. This means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus and any applicable prospectus supplement, except for information superseded by information contained in this prospectus or the applicable prospectus supplement itself or in any subsequently filed incorporated document. This prospectus and any applicable prospectus supplement incorporate by reference the documents set forth below that we have previously filed with the SEC, other than information in such documents that is deemed to be furnished and not filed. These documents contain important information about us and our business and financial condition. Any report or information within any of the documents referenced below that is furnished, but not filed, shall not be incorporated by reference into this prospectus:

We also incorporate by reference any future filings made by us with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act (excluding any information furnished to, rather than filed with, the SEC), including after the date of the initial registration statement of which this prospectus is a part and prior to effectiveness of the registration statement, and after effectiveness of the registration statement and prior to the termination of the offering of the securities made by this prospectus. Information in such future filings updates and supplements the information provided in this prospectus. Any statements in any such future filings will automatically be deemed to modify and supersede any information in any document we previously filed with the SEC that is incorporated or deemed to be incorporated herein by reference to the extent that statements in the later filed document modify or replace such earlier statements.

You may request a copy of these filings, at no cost, by writing or calling us at the following address or telephone number below:

Those copies will not include exhibits, unless the exhibits have specifically been incorporated by reference in this document or you specifically request them.

Summary

This summary highlights selected information appearing in this prospectus. Because it is a summary, it may not contain all of the information that may be important to you. To understand this offering fully, you should read this entire prospectus carefully, including the information set forth in the section entitled “Risk Factors” contained in this prospectus and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the information incorporated by reference into this prospectus, including our consolidated financial statements and related notes and the exhibits to the registration statement of which this prospectus is a part, before making an investment decision. This prospectus includes forward-looking statements that involve risks and uncertainties. See “Cautionary Note Regarding Forward-Looking Statements.”

NioCorp Developments Ltd.

NioCorp is developing the Elk Creek Project (as defined below) located in southeast Nebraska. The “Elk Creek Project” is a development-stage property that has disclosed niobium, scandium, and titanium reserves and resources and disclosed rare earth mineral resources. The Company is continuing technical and economic studies around the rare earths contained in the Elk Creek Project’s mineral resource in order to determine whether extraction of rare earth elements can be reasonably justified and economically viable after taking into account all relevant factors. Niobium is used to produce various superalloys that are extensively used in high performance aircraft and jet turbines. It also is used in high-strength, low-alloy steel, a stronger steel used in automobiles, bridges, structural systems, buildings, pipelines, and other applications that generally increases strength and/or reduces weight, which can result in environmental benefits, including reduced fuel consumption and material usage and fewer air emissions. Scandium can be combined with aluminum to make high-performance alloys with increased strength and improved corrosion resistance. Scandium also is a critical component of advanced solid oxide fuel cells, an environmentally preferred technology for high-reliability, distributed electricity generation. Titanium is a component of various superalloys and other applications that are used for aerospace applications, weapons systems, protective armor, medical implants, and many others. It also is used in pigments for paper, paint, and plastics. Rare earths are critical to electrification and decarbonization initiatives and can be used to manufacture the strongest permanent magnets commercially available.

Our primary business strategy is to advance our Elk Creek Project to commercial production. We are focused on obtaining additional funds to carry out our near-term planned work programs associated with securing the project financing necessary to complete mine development and construction of the Elk Creek Project.

Corporate Information

Our Common Shares trade on The Nasdaq Global Market under the symbol “NB.” Our principal executive office is located at 7000 South Yosemite Street, Suite 115, Centennial, CO 80112, and our telephone number is (720) 334-7066. Our website address is www.niocorp.com. This website address is not intended to be an active link, and information on, or accessible through, our website is not incorporated by reference into this prospectus and you should not consider any information on, or that can be accessed from, our website as part of this prospectus or any accompanying prospectus supplement.

Investing in our securities involves a high degree of risk. Prior to making a decision about investing in our securities, you should carefully consider the specific risk factors discussed under the heading “Risk Factors” in our most recent Annual Report on Form 10-K and in our most recent Quarterly Reports on Form 10-Q, which are or will be incorporated herein by reference and may be amended, supplemented or superseded from time to time by other reports we file with the SEC in the future. You should also refer to the other information in this prospectus and the applicable prospectus supplement, including our financial statements and the related notes incorporated by reference in this prospectus. The risks and uncertainties we have described are not the only risks we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations. If any of these risks actually occurs, our business, results of operations and financial condition could suffer and could result in a complete loss of your investment.

This prospectus and the other documents incorporated by reference into this prospectus contain or may contain “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act, and “forward-looking information” within the meaning of applicable Canadian securities legislation (collectively, “forward-looking statements”). Such forward-looking statements concern our anticipated results and developments in the operations of the Company in future periods, planned exploration activities, the adequacy of the Company’s financial resources, and other events or conditions that may occur in the future.

Forward-looking statements have been based upon our current business and operating plans, as approved by the Company’s Board of Directors, and may include statements regarding the anticipated benefits of the transactions contemplated by the Business Combination Agreement (the “Business Combination Agreement”), dated September 25, 2022, between NioCorp, GXII, Big Red Merger Sub Ltd, a Delaware corporation and a direct, wholly owned subsidiary of the Company (the “Transactions”), including NioCorp’s ability to access the full amount of the expected net proceeds of the Standby Equity Purchase Agreement, dated January 26, 2023 (as amended, the “Yorkville Equity Facility Financing Agreement”), between NioCorp and YA II PN, Ltd. (“YA”), a fund managed by Yorkville Advisors Global, LP, through April 1, 2026; NioCorp’s ability to receive a final commitment of financing from the Export-Import Bank of the United States (“EXIM”); anticipated benefits of the listing of the Common Shares on Nasdaq; 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 expectation and ability to produce niobium, scandium, and titanium at the Elk Creek Project; NioCorp’s plans to produce and supply specific products and market demand for those products; the Elk Creek Project’s ability to produce multiple critical metals; NioCorp’s expectation that the process improvements resulting from previously completed recovery process improvement testing could lead to greater efficiencies and cost savings in the Elk Creek Project; the Elk Creek Project’s projected ore production and mining operations over its expected mine life; the completion and content of an updated technical report for the Elk Creek Project; the completion of technical and economic analyses on the potential addition of magnetic rare earth oxides to NioCorp’s planned product suite; anticipated benefits of the electrification of access to the Elk Creek Project mine site; the exercise of options to purchase additional land parcels; the execution of contracts with engineering, procurement and construction companies; the advancement of offtake discussions with potential customers; NioCorp’s ongoing evaluation of the impact of inflation, supply chain issues and geopolitical unrest on the Elk Creek Project’s economic model; 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. 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 ability to recognize the anticipated benefits of the Transactions, including NioCorp’s ability to access the full amount of the expected net proceeds under the Yorkville Equity Facility Financing Agreement through April 1, 2026; unexpected costs related to the Transactions; the outcome of any legal proceedings that may be instituted against NioCorp following closing of the Transactions; NioCorp’s ability to receive a final commitment of financing from EXIM on the anticipated timeline, on acceptable terms, or at all; NioCorp’s ability to continue to meet Nasdaq listing standards; NioCorp’s ability to operate as a going concern; risks relating to the Common Shares, including price volatility, lack of dividend payments and dilution or the perception of the likelihood any of the foregoing; NioCorp’s requirement of significant additional capital; the extent to which NioCorp’s level of indebtedness and/or the terms contained in agreements governing NioCorp’s indebtedness or the Yorkville Equity Facility Financing Agreement may impair NioCorp’s ability to obtain additional financing, on acceptable terms, or at all; covenants contained in agreements with NioCorp’s secured creditors that may affect its assets; NioCorp’s limited operating history; NioCorp’s history of losses; the material weaknesses in NioCorp’s internal control over financial reporting, NioCorp’s efforts to remediate such material weaknesses and the timing of remediation; the possibility that NioCorp may qualify as a passive foreign investment company (“PFIC”) under the U.S. Internal Revenue Code of 1986, as amended (the “Code”); the potential that the Transactions 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; 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; current and future offtake agreements, joint ventures, and partnerships; NioCorp’s ability to attract qualified management; the effects of global health crises on NioCorp’s business plans, financial condition and liquidity; estimates of mineral resources and reserves; mineral exploration and production activities; feasibility study results; the results of metallurgical testing; the results of technological research; 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 industry; 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; 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, or development activities; the 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 of grades of reserves and resources; claims on the title to NioCorp’s properties; potential future litigation; and NioCorp’s lack of insurance covering all of NioCorp’s operations.

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 Part I, Item 1A. “Risk Factors” contained in our most recent Annual Report on Form 10-K, and Part II, Item 1A. “Risk Factors” contained in our subsequent Quarterly Reports on Form 10-Q, as well as any amendments thereto, which are incorporated by reference into this prospectus and the applicable prospectus supplement in their entirety, together with other information in this prospectus and the applicable prospectus supplement and the documents incorporated by reference herein and therein. See the sections of this prospectus entitled “Where You Can Find More Information” and “Information Incorporated by Reference.”

The Company’s forward-looking statements contained in this prospectus are based on the beliefs, expectations, and opinions of management as of the date of this prospectus. 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.

Unless the applicable prospectus supplement states otherwise, we expect to use the net proceeds of the sale of the securities offered by this prospectus for working capital and general corporate purposes, including to advance our efforts to launch construction of the Elk Creek Project and move it to commercial operation.

As of the date of this prospectus, we have not identified as probable any specific material proposed uses of these proceeds. If, as of the date of any prospectus supplement, we have identified any such uses, we will describe them in the prospectus supplement. Pending any such uses, we may temporarily invest the net proceeds.

The authorized capital of the Company consists of an unlimited number of Common Shares without par value, of which 37,576,647 were issued and outstanding as of June 12, 2024. The holders of Common Shares are entitled to receive notice of and attend all meetings of shareholders, with each Common Share held entitling the holder to one vote on any resolution to be passed at such shareholder meetings. The holders of Common Shares are entitled to dividends if, as and when declared by the Company’s Board of Directors. The Common Shares are entitled, upon liquidation, dissolution, or winding up of NioCorp, to receive the remaining assets of NioCorp available for distribution to shareholders. There are no pre-emptive, conversion, or redemption rights attached to the Common Shares.

There are no governmental laws, decrees, or regulations in Canada that restrict the export or import of capital, including foreign exchange controls, or that affect the remittance of dividends, interest or other payments to non-resident holders of the securities of NioCorp, other than as discussed below and Canadian withholding tax. See “—Certain Canadian Federal Income Tax Considerations for U.S. Residents.”

The following generally summarizes certain Canadian federal income tax consequences generally applicable under the Income Tax Act (Canada) and the regulations enacted thereunder (collectively, the “Canadian Tax Act”) and the Canada-United States Tax Convention (1980) (the “Convention”) to the holding and disposition of Common Shares.

Comment is restricted to holders of Common Shares each of whom, at all material times for the purposes of the Canadian Tax Act and the Convention, (i) is resident solely in the United States for tax purposes, (ii) is a “qualifying person” under and entitled to the benefits of the Convention, (iii) holds all Common Shares as capital property, (iv) holds no Common Shares that are “taxable Canadian property” (as defined in the Canadian Tax Act) of the holder, (v) deals at arm’s length with and is not affiliated with the Company, (vi) does not and is not deemed to use or hold any Common Shares in a business carried on in Canada, (vii) is not an insurer that carries on business in Canada and elsewhere, (viii) is not an “authorized foreign bank” (as defined in the Canadian Tax Act), and (ix) has not entered into a “derivative forward agreement” (as defined in the Canadian Tax Act) with respect to the Common Shares (each such holder, a “U.S. Resident Holder”).

Certain U.S.-resident entities that are fiscally transparent for United States federal income tax purposes (including limited liability companies) may not in all circumstances be entitled to the benefits of the Convention. Members of or holders of an interest in such an entity that holds Common Shares should consult their own tax advisers regarding the extent, if any, to which the benefits of the Convention will apply to the entity in respect of its Common Shares.

Generally, a U.S. Resident Holder’s Common Shares will be considered to be capital property of such holder provided that the U.S. Resident Holder is not a trader or dealer in securities, did not acquire, hold, or dispose of the Common Shares in one or more transactions considered to be an adventure or concern in the nature of trade (i.e., speculation), and does not hold the Common Shares in the course of carrying on a business.

This summary is based on the current provisions of the Canadian Tax Act and the Convention in effect as of the date prior to the date hereof, all specific proposals to amend the Canadian Tax Act and Convention publicly announced by or on behalf of the Minister of Finance (Canada) prior to the date hereof, and the current published administrative policies and assessing practices of the Canada Revenue Agency (the “CRA”). It is assumed that all such amendments will be enacted as currently proposed, and that there will be no other material change to any applicable law or administrative policy or assessing practice, whether by way of judicial, legislative or governmental decision or action, although no assurance can be given in these respects. This summary is not exhaustive of all possible Canadian federal income tax considerations. Except as otherwise expressly provided, this summary does not take into account any provincial, territorial, or foreign tax considerations, which may differ materially from those set out herein.

This summary is of a general nature only, is not exhaustive of all possible Canadian federal income tax considerations, and is not intended to be and should not be construed as legal or tax advice to any particular U.S. Resident Holder. U.S. Resident Holders are urged to consult their own tax advisers for advice with respect to their particular circumstances. The discussion below is qualified accordingly.

Generally, a U.S. Resident Holder’s Common Shares will not constitute “taxable Canadian property” of such holder at a particular time at which the Common Shares are listed on a “designated stock exchange” (which currently includes Nasdaq) unless both of the following conditions are concurrently met:

Common Shares may also be deemed to be “taxable Canadian property” in certain circumstances set out in the Canadian Tax Act.

A U.S. Resident Holder who disposes or is deemed to dispose of one or more Common Shares generally should not thereby incur any liability for Canadian federal income tax in respect of any capital gain arising as a consequence of the disposition.

A U.S. Resident Holder to whom the Company pays or credits or is deemed to pay or credit a dividend on such holder’s Common Shares will be subject to Canadian withholding tax, and the Company will be required to withhold the tax from the dividend and remit it to the CRA for the holder’s account. The rate of withholding tax under the Canadian Tax Act is 25% of the gross amount of the dividend, but should generally be reduced under the Convention to 15% (or, if the U.S. Resident Holder is a company which is the beneficial owner of at least 10% of the voting stock of the Company, 5%) of the gross amount of the dividend. For this purpose, a company that is a resident of the United States for purposes of the Canadian Tax Act and the Convention and is entitled to the benefits of the Convention shall be considered to own the voting stock of the Company owned by an entity that is considered fiscally transparent under the laws of the United States and that is not a resident of Canada, in proportion to such company’s ownership interest in that entity.

Limitations on the ability to acquire and hold Common Shares may be imposed by the Competition Act (Canada). This legislation permits the Commissioner of Competition of Canada (the “Commissioner”) to review any acquisition of a significant interest in the Company. This legislation grants the Commissioner jurisdiction to challenge such an acquisition before the Canadian Competition Tribunal if the Commissioner believes that it would, or would be likely to, result in a substantial lessening or prevention of competition in any market in Canada.

The Investment Canada Act subjects an acquisition of control of a company by a non-Canadian to government review if the enterprise value of such company, as calculated pursuant to the legislation, exceeds a threshold amount. A reviewable acquisition may not proceed unless the relevant minister is satisfied that the investment is likely to result in a net benefit to Canada. Under the national-security-review regime in the Investment Canada Act, review on a discretionary basis may also be undertaken by the federal government in respect of a broad range of investments by a non-Canadian. No financial threshold applies to a national security review. The relevant test is whether such investment by a non-Canadian could be “injurious to national security.”

In connection with the closing of the Transactions (the “Closing”), pursuant to the Business Combination Agreement, the Company assumed the Warrant Agreement, dated as of March 17, 2021 (the “GXII Warrant Agreement”), by and between GXII and Continental Stock Transfer & Trust Company (“CST”), as warrant agent, and each share purchase warrant of GXII thereunder (the “GXII Warrants”) that was issued and outstanding immediately prior to March 17, 2023 was converted into one Warrant (the “NioCorp Assumed Warrants”) pursuant to the assignment, assumption and amendment agreement to the GXII Warrant Agreement, dated March 17, 2023 (the GXII Warrant Agreement, as so amended, the “NioCorp Assumed Warrant Agreement”), among NioCorp, GXII, CST, as existing warrant agent, and Computershare Inc. and its affiliate Computershare Trust Company, N.A., together as successor warrant agent (the “NioCorp Assumed Warrant Agent”). In connection with the Closing, NioCorp issued (a) 9,999,959 public NioCorp Assumed Warrants in respect of the GXII Warrants that were publicly traded prior to the Closing and (b) 5,666,667 NioCorp Assumed Warrants to GX Sponsor II LLC (the “Sponsor”) in respect of the GXII Warrants that it held prior to the Closing, which NioCorp Assumed Warrants were subsequently distributed by the Sponsor to its members in connection with the Closing.

Both the public NioCorp Assumed Warrants and the NioCorp Assumed Warrants issued to the Sponsor are subject to the terms of the NioCorp Assumed Warrant Agreement and are identical, with certain exceptions applicable to the NioCorp Assumed Warrants issued to the Sponsor for so long as such NioCorp Assumed Warrants are held by the Sponsor, its members, or their respective affiliates and other permitted transferees. In accordance with the NioCorp Assumed Warrant Agreement, any NioCorp Assumed Warrants issued to the Sponsor that are held by someone other than the Sponsor, its members, or their respective affiliates and other permitted transferees, are treated as public NioCorp Assumed Warrants.

Each NioCorp Assumed Warrant is exercisable on and after April 16, 2023 until its expiration for 1.11829212 Common Shares at a price of $11.50 per 1.11829212 Common Shares (subject to adjustments for stock splits, stock dividends, reorganizations, recapitalizations and the like). Under the terms of NioCorp Assumed Warrant Agreement, for so long as the NioCorp Assumed Warrants issued to the Sponsor are held by the Sponsor, its members, or their respective affiliates and other permitted transferees, such holders have the right to elect to exercise those NioCorp Assumed Warrants on a cashless basis. For such NioCorp Assumed Warrants exercised on a cashless basis after the Closing, the holder will be entitled to pay the exercise price for those NioCorp Assumed Warrants by surrendering all or portion of the cash and/or Common Shares (valued at their fair market value) into which those NioCorp Assumed Warrants are exercisable as shall be elected by the holder. For this purpose, Common Shares so surrendered will be deemed to have a “fair market value” equal to the average reported last sale price of the Common Shares for the 10 trading days ending on the third trading day prior to the date of exercise of the applicable NioCorp Assumed Warrants.

The NioCorp Assumed Warrants will expire at 5:00 p.m., New York City time, on March 17, 2028 or earlier upon redemption or liquidation.

The Company will not be obligated to deliver any Common Shares pursuant to the exercise of a NioCorp Assumed Warrant and will have no obligation to settle such exercise unless a registration statement under the Securities Act with respect to the Common Shares underlying the NioCorp Assumed Warrants is then effective and a prospectus relating thereto is current, subject to the Company satisfying its obligations described below with respect to registration. No NioCorp Assumed Warrant will be exercisable and the Company will not be obligated to issue Common Shares upon exercise of a NioCorp Assumed Warrant unless Common Shares issuable upon such exercise have been registered, qualified or deemed to be exempt under the securities laws of the state of residence of the registered holder of the NioCorp Assumed Warrants. In the event that the conditions in the two immediately preceding sentences are not satisfied with respect to a NioCorp Assumed Warrant, the holder of such NioCorp Assumed Warrant will not be entitled to exercise such NioCorp Assumed Warrant and such NioCorp Assumed Warrant may have no value and expire worthless. In no event will the Company be required to net cash settle any NioCorp Assumed Warrant.

The NioCorp Assumed Warrants, and the underlying Common Shares issuable upon the exercise thereof, were registered under the Securities Act pursuant to the Company’s registration statement on Form S-4, originally filed on November 7, 2022, as subsequently amended, which was declared effective by the SEC on February 8, 2023. The ongoing registered offering of the Common Shares underlying the NioCorp Assumed Warrants is being conducted pursuant to the Company’s registration statement on Form S-3, originally filed on April 14, 2023, as subsequently post-effectively amended to convert such registration statement to Form S-1, which was declared effective on October 30, 2023.

The Company will have the right to call the public NioCorp Assumed Warrants for redemption at any time following the Closing Date:

The NioCorp Assumed Warrants issued to the Sponsor are not redeemable by the Company for so long as such NioCorp Assumed Warrants are held by the Sponsor, its members, or their respective affiliates or other permitted transferees. In addition, the Company may not exercise its redemption right if the issuance of Common Shares upon exercise of the NioCorp Assumed Warrants is not exempt from registration or qualification under applicable state blue sky laws or the Company is unable to effect such registration or qualification.

If the Company calls the public NioCorp Assumed Warrants for redemption as described above, the Company will have the option to require any holder that wishes to exercise its public NioCorp Assumed Warrant to do so on a “cashless basis.” In determining whether to require all holders to exercise their public NioCorp Assumed Warrants on a “cashless basis,” the Company will consider, among other factors, its cash position, the number of NioCorp Assumed Warrants that are outstanding and the dilutive effect on the Company’s shareholders of issuing the maximum number of Common Shares issuable upon the exercise of the NioCorp Assumed Warrants. If the Company takes advantage of this option, all holders of public NioCorp Assumed Warrants would pay the exercise price by surrendering their NioCorp Assumed Warrants for that number of Common Shares equal to the quotient obtained by dividing (x) the product of the number of Common Shares underlying the public NioCorp Assumed Warrants, multiplied by the difference between the exercise price of the NioCorp Assumed Warrants and the “fair market value” (defined below) by (y) the fair market value. The “fair market value” shall mean the average reported last sale price of the Common Shares for the 10 trading days ending on the third trading day prior to the date on which the notice of redemption is sent to the holders of public NioCorp Assumed Warrants. If the Company takes advantage of this option, the notice of redemption will contain the information necessary to calculate the number of Common Shares to be received upon exercise of the NioCorp Assumed Warrants, including the “fair market value” in such case. Requiring a cashless exercise in this manner will reduce the number of Common Shares to be issued and thereby lessen the dilutive effect of a redemption of the public NioCorp Assumed Warrants. If the Company calls the public NioCorp Assumed Warrants for redemption and does not take advantage of this option, the Sponsor, its members, and their respective affiliates and other permitted transferees would still be entitled to exercise their NioCorp Assumed Warrants for cash or on a cashless basis using the same formula described above that other NioCorp Assumed Warrant holders would have been required to use had all NioCorp Assumed Warrant holders been required to exercise their NioCorp Assumed Warrants on a cashless basis, as described in more detail below.

A holder of a NioCorp Assumed Warrant may notify the Company in writing in the event it elects to be subject to a requirement that such holder will not have the right to exercise such NioCorp Assumed Warrant, to the extent that after giving effect to such exercise, such holder (together with such holder’s affiliates), to the NioCorp Assumed Warrant Agent’s actual knowledge, would beneficially own in excess of 4.9% or 9.8% (or such other amount as a holder may specify) of the Common Shares outstanding immediately after giving effect to such exercise.

The NioCorp Assumed Warrants have certain anti-dilution and adjustments rights upon certain events.

The NioCorp Assumed Warrants may be exercised upon surrender of the certificate representing such NioCorp Assumed Warrants on or prior to the expiration date at the offices of the NioCorp Assumed Warrant Agent, with the exercise form on the reverse side of such certificate completed and executed as indicated, accompanied by full payment of the exercise price (or on a cashless basis, if applicable), by certified or official bank check payable to the order of the NioCorp Assumed Warrant Agent or by wire transfer, for the number of NioCorp Assumed Warrants being exercised. The NioCorp Assumed Warrant holders will not have the rights or privileges of holders of Common Shares or any attendant voting rights until they exercise their NioCorp Assumed Warrants and receive Common Shares. After the issuance of Common Shares upon exercise of the NioCorp Assumed Warrants, each holder will be entitled to one (1) vote for each Common Share held of record on all matters to be voted on by NioCorp shareholders.

If, upon exercise of the NioCorp Assumed Warrants, a holder would be entitled to receive a fractional interest in a share, the Company will, upon exercise, round down to the nearest whole number of Common Shares to be issued to the NioCorp Assumed Warrant holder.

The NioCorp Assumed Warrants were issued in registered form under the NioCorp Assumed Warrant Agreement. The NioCorp Assumed Warrant Agreement may be amended by the parties thereto without the consent of any registered holder (i) for the purpose of curing any ambiguity, or curing, correcting or supplementing any mistake, or adding or changing any other provisions with respect to matters or questions arising under NioCorp Assumed Warrant Agreement as the parties may deem necessary or desirable and that the parties deem shall not adversely affect the interest of the registered holders of the NioCorp Assumed Warrants, and (ii) to provide for the delivery of such kind and amount of Common Shares or other securities or property (including cash) receivable upon a reclassification, reorganization, merger or consolidation, or upon a dissolution following any such sale or transfer, that the holder of NioCorp Assumed Warrants would have received if such holder had exercised his, her or its NioCorp Assumed Warrants immediately prior to such event. All other modifications or amendments, including any amendment to increase the warrant price or shorten the exercise period, shall require the vote or written consent of the registered holders of a majority of the then outstanding public NioCorp Assumed Warrants. Any amendment solely to the NioCorp Assumed Warrants issued to the Sponsor and that are held by the Sponsor, its members, or their respective affiliates or other permitted transferees, shall require the vote or written consent of a majority of the holders of the then outstanding NioCorp Assumed Warrants issued to the Sponsor.

On January 26, 2023, NioCorp entered into the Securities Purchase Agreement (the “Yorkville Convertible Debt Financing Agreement”) with YA. Pursuant to the Yorkville Convertible Debt Financing Agreement, YA advanced a total amount of $15,360,000 to NioCorp in consideration of the issuance by NioCorp to YA of $16,000,000 aggregate principal amount of convertible debentures (the “Convertible Debentures”) at the time of Closing (the “Debenture Closing”). As of June 12, 2024, there was $550,000 aggregate principal amount of the Convertible Debentures outstanding.

Each Convertible Debenture issued under the Yorkville Convertible Debt Financing Agreement is an unsecured obligation of NioCorp, matures on September 17, 2024, which maturity may be extended for one six-month period in certain circumstances at the option of NioCorp, and incurs a simple interest rate obligation of 5.0% per annum (which will increase to 15.0% per annum upon the occurrence of an event of default). The outstanding principal amount of, accrued and unpaid interest, if any, on, and premium, if any, on the Convertible Debentures must be paid by NioCorp in cash when the same becomes due and payable under the terms of the Convertible Debentures at their stated maturity, upon their redemption or otherwise.

Subject to certain limitations contained within the Yorkville Convertible Debt Financing Agreement and the Convertible Debentures, including those as described below, holders of the Convertible Debentures will be entitled to convert the principal amount of, and accrued and unpaid interest, if any, on each Convertible Debenture, in whole or in part, from time to time over their term, into a number of Common Shares equal to the quotient of the principal amount and accrued and unpaid interest, if any, being converted divided by the Conversion Price. The “Conversion Price” means, as of any Conversion Date (as defined below) or other date of determination, the greater of (i) 90% of the average of the daily U.S. dollar volume-weighted average price of the Common Shares on the principal U.S. market for the Common Shares as reported by Bloomberg Financial Markets during the five consecutive trading days immediately preceding the date on which the holder exercises its conversion right in accordance with the requirements of the Yorkville Convertible Debt Financing Agreement (the “Conversion Date”) or other date of determination, but not lower than the Floor Price (as defined below), and (ii) the five-day volume-weighted average price of the Common Shares on the TSX (or on the principal U.S. market if the majority of the trading volume and value of the Common Shares occurred on Nasdaq during the relevant period) for the five consecutive trading days immediately prior to the Conversion Date or other date of determination less the maximum applicable discount allowed by the TSX. The “Floor Price” means a price of $2.1435 per share, which is equal to the lesser of (a) 30% of the average of the daily volume-weighted average price of the Common Shares on the principal U.S. market for the Common Shares as reported by Bloomberg Financial Markets during the five consecutive trading days immediately preceding the Debenture Closing and (b) 30% of the average of the volume-weighted average price of the Common Shares on the principal U.S. market for the Common Shares as reported by Bloomberg Financial Markets during the five consecutive trading days immediately following the Debenture Closing, subject to certain adjustments to give effect to any stock dividend, stock split, reverse stock split, recapitalization or similar event.

The terms of the Convertible Debentures restrict the number of Convertible Debentures that may be converted during each calendar month by YA at a Conversion Price below a fixed price equal to approximately $8.9422 (i.e., the quotient of $10.00 divided by 1.11829212 (being the number of Common Shares that were exchanged for each share of GXII at the Closing, after giving effect to the reverse stock split at a ratio of 10-for-1 effectuated by each of NioCorp and ECRC on the date of Closing (the “Reverse Stock Split”))), subject to adjustment to give effect to any stock dividend, stock split, reverse stock split, recapitalization or similar event. The Convertible Debentures are subject to customary anti-dilution adjustments.

The terms of the Convertible Debentures restrict the conversion of Convertible Debentures by YA if such a conversion would cause YA to exceed certain beneficial ownership thresholds in NioCorp or such a conversion would cause the aggregate number of Common Shares issued pursuant to the Yorkville Convertible Debt Financing Agreement to exceed the thresholds for issuance of Common Shares under the rules of Nasdaq, unless prior shareholder approval is obtained.

In conjunction with the Debenture Closing, NioCorp issued to YA pursuant to the Yorkville Convertible Debt Financing Agreement financing warrants (the “Financing Warrants”) to purchase 1,789,267 Common Shares, which is equal to the quotient of the principal amount of Convertible Debentures issued in such Debenture Closing divided by the “Exercise Price,” which is equal to approximately $8.9422 (i.e., the quotient of $10.00 divided by 1.11829212 (being the number of Common Shares that were exchanged for each share of GXII at the Closing, after giving effect to the reverse stock split at a ratio of 10-for-1 effectuated by each of NioCorp and ECRC on the Closing Date)), in each case, subject to adjustment to give effect to any stock dividend, stock split, reverse stock split, recapitalization or similar event.

The Financing Warrants are exercisable, in whole or in part, but not in increments of less than $50,000 aggregate Exercise Price (unless the remaining aggregate Exercise Price is less than $50,000), beginning on May 4, 2023 and may be exercised at any time prior to their expiration. Holders of the Financing Warrants may exercise their Financing Warrants, at their election, by paying the Exercise Price in cash or, if at any time there is no effective registration statement registering, or no current prospectus available for, the resale of the underlying Common Shares, on a cashless exercise basis. On each of the first 12 monthly anniversaries of September 17, 2023, 1/12th of the Financing Warrants will expire.

The Financing Warrants have customary anti-dilution adjustments to be determined in accordance with the requirements of the applicable stock exchanges.

The terms of the Financing Warrants restrict the exercise of Financing Warrants by YA if such an exercise would cause YA to exceed certain beneficial ownership thresholds in NioCorp or such an exercise would cause the aggregate number of Common Shares issued pursuant to the Yorkville Convertible Debt Financing Agreement to exceed the thresholds for issuance of Common Shares under the rules of Nasdaq, unless prior shareholder approval is obtained.

On April 12, 2024, the Company issued and sold to the YA and Lind Global Fund II LP (“Lind”), in a private placement (the “April 2024 Private Placement”), $8.0 million aggregate principal amount of unsecured notes (the “Notes”), pursuant to a Securities Purchase Agreement, dated April 11, 2024 (the “Purchase Agreement”), between the Company and each of YA and Lind, as purchasers (in such capacity, the “Purchasers”). Pursuant to the terms of the Notes, subject to certain exceptions as described below, on the first day of each calendar month, beginning on June 1, 2024 (excluding August 2024) (a “Payment Date”), the Company will be required to repay a portion of the outstanding balance of all of the Notes, on a pro-rata basis, in an amount equal to the sum of (i) $1.4 million of principal (or the outstanding principal if less than such amount) in the aggregate among all of the outstanding Notes, plus (ii) 8.0% of the principal amount being paid (the “Payment Premium”), and (iii) accrued and unpaid interest, if any, as of the Payment Date. The Company is required to make payments on each Payment Date until the entire outstanding principal is repaid, but will not have an obligation to make a payment on a Payment Date if the Equity Conditions (as defined below) are satisfied.

Pursuant to the Purchase Agreement, the Purchasers advanced an aggregate of $6.96 million to NioCorp in consideration of the issuance by NioCorp to the Purchasers of $8.0 million aggregate principal amount of Notes and Warrants (the “April 2024 Warrants”) to purchase up to 615,385 Common Shares (the “April 2024 Warrant Shares”). Each April 2024 Warrant is exercisable for one Common Share for cash or, if at any time there is no effective registration statement registering, or no current prospectus available for, the resale of the underlying Common Shares, on a cashless basis at the option of the holder, at a price per Common Share of $3.25 (the “April 2024 Exercise Price”), subject to adjustment for recapitalizations, stock splits, reverse stock splits or similar events, and expires April 12, 2027.

Subject to certain limitations, including those as described below, contained within the Notes, holders of the Notes will be entitled to convert the principal amount of, accrued and unpaid interest, if any, and any Payment Premium that has become due and payable on each Note, from time to time over their term, into a number of Common Shares equal to the quotient of the amount being converted divided by the fixed conversion price of $2.75 per Common Share (the “Fixed Conversion Price”) up to a maximum of 3,141,817 Common Shares (together with the April 2024 Warrant Shares, the “Underlying Shares”). The terms of the Notes restrict the conversion of the Notes by a holder if such a conversion or exercise would cause such holder to exceed certain beneficial ownership thresholds in NioCorp.

The Notes are the unsecured obligations of NioCorp and will mature on December 31, 2024. The Notes will incur a simple interest rate obligation of 0.0% per annum (which will increase to 18.0% per annum upon the occurrence of an event of default). The outstanding principal amount of, accrued and unpaid interest, if any, on, and the Payment Premium, if any, on the Notes must be paid by NioCorp in cash when the same becomes due and payable under the terms of the Notes at their stated maturity, upon their redemption or otherwise.

As mentioned above, NioCorp is required to make payments on each Payment Date until the entire outstanding principal is repaid, but will not have an obligation to make a payment on a Payment Date if the Equity Conditions are satisfied. The “Equity Conditions” means (i) on each of the five consecutive trading days prior a Payment Date (the “Measuring Period”) a registration statement registering the resale by the Purchasers of the Underlying Shares under the Securities Act (the “Underlying Shares Registration Statement”) is effective and available for the resale by the Purchasers of all Underlying Shares, (ii) NioCorp has no knowledge of any fact that would cause the Underlying Shares Registration Statement not to be effective and available for the resale of the Underlying Shares, (iii) on each day during the Measuring Period, the Common Shares are designated for quotation on Nasdaq, or on such other market or exchange on which the Common Shares are then listed or traded to the extent such other market or exchange is the principal U.S. trading market for the Common Shares (the “Principal U.S. Market”), and have not been suspended from trading nor have delisting or suspension of trading been threatened or pending, (iv) during the Measuring Period, an event of default has not occurred, (v) on each trading day during the Measuring Period, the daily U.S. dollar volume-weighted average price for a Common Share on the Principal U.S. Market as reported by Bloomberg Financial Markets is greater than 120% of the Fixed Conversion Price, (vi) on each trading day during the Measuring Period the average daily volume traded exceeded $500,000, and (vii) there is no limitation on conversion under the terms of Notes. In addition, any Payment Date and the amount payable to the holder of a Note on any such Payment Date may be modified from time to time upon mutual written consent of NioCorp and such holder.

Pursuant to the terms of the Notes, to the extent a holder is a party to Yorkville Equity Facility Financing Agreement, for so long as any amount remains outstanding under such holder’s Note, the amount of cash received by the Company as payment from such holder in respect of an Advance (as defined in the Yorkville Equity Facility Financing Agreement) is subject to a right of offset, exercisable in such holder’s sole discretion, against an equal amount of principal, accrued and unpaid interest, if any, and other amounts that have become due and payable under the Note, not to exceed $1.512 million in any calendar month.

The Notes may also be redeemed at NioCorp’s option at any time and from time to time over their term at a redemption price equal to the principal amount being redeemed, plus the Payment Premium, plus accrued and unpaid interest, if any, as of the redemption date.

The Notes contain events of default customary for instruments of their type (with customary grace periods, as applicable) and provide that, upon the occurrence of an event of default arising from certain events of bankruptcy or insolvency with respect to NioCorp, all outstanding Notes will become due and payable immediately without further action or notice. If any other type of event of default occurs and is continuing, then any holder may declare all of its Notes to be due and payable immediately.

Pursuant to a global guaranty agreement, dated as of April 11, 2024, among ECRC and 0896800 B.C. Ltd. (together with ECRC, the “Guarantors”), the Guarantors guaranteed the full, prompt and unconditional payment when due (whether at maturity, by acceleration or otherwise), and the performance of all liabilities, agreements and other obligations of NioCorp to the Purchasers contained in the Notes and the Purchase Agreement, to the extent such liabilities, agreements and obligations are payable in cash.

On April 12, 2024, in connection with the closing of the April 2024 Private Placement, the Company issued to the Purchasers, in proportion to the aggregate principal amount of Notes issued to each Purchaser, April 2024 Warrants to purchase the April 2024 Warrant Shares, which is equal to 25% of the aggregate principal amount of Notes issued to the Purchasers divided by the April 2024 Exercise Price, subject to any adjustment to give effect to any stock dividend, stock split or recapitalization.

The terms of the April 2024 Warrants restrict the exercise of the April 2024 Warrants by a holder if such an exercise would cause such holder to exceed certain beneficial ownership thresholds in NioCorp.

The April 2024 Warrants will be exercisable, in whole or in part, but not in increments of less than $50,000 aggregate April 2024 Exercise Price (unless the remaining aggregate April 2024 Exercise Price is less than $50,000), at any time on or before April 12, 2027. Holders of the April 2024 Warrants may exercise their April 2024 Warrants, at their election, by paying the April 2024 Exercise Price in cash or on a cashless exercise basis, if at any time there is no effective registration statement or prospectus available for the resale of the underlying Common Shares or an event of default under the Notes has occurred and is continuing.

The April 2024 Warrants are subject to adjustment for any stock dividend or other distribution, stock split, reverse stock split or recapitalization

The following description, together with the additional information we may include in any applicable prospectus supplement, summarizes the material terms and provisions of the Warrants that we may offer under this prospectus. While the terms we have summarized below will apply generally to any Warrants that we may offer under this prospectus, we will describe the particular terms of any series of Warrants in more detail in the applicable prospectus supplement. The terms of any Warrants offered under a prospectus supplement may differ from the terms described below.

We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from another report that we file with the SEC, the form of Warrant agreement or Warrant indenture, which may include a form of Warrant certificate, that describes the terms of the particular series of Warrants we are offering before the issuance of the related series of Warrants. The following summary of material provisions of the Warrants and the Warrant agreements and the Warrant indentures are subject to, and qualified in their entirety by reference to, all the provisions of the Warrant agreement or Warrant indenture, and Warrant certificate, applicable to a particular series of Warrants. We urge you to read the applicable prospectus supplement related to the particular series of Warrants that we sell under this prospectus, as well as the complete Warrant agreements, Warrant indentures and Warrant certificates that contain the terms of the Warrants.

We will describe in the applicable prospectus supplement the terms relating to Warrants being offered including:

Before exercising their Warrants, holders of Warrants will not have any of the rights of holders of the Common Shares purchasable upon such exercise, including the right to receive dividends, if any, or payments upon our liquidation, dissolution or winding up of our affairs or to exercise voting rights, if any.

Unless we otherwise specify in the applicable prospectus supplement, each Warrant will entitle the holder to purchase one Common Share at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the Warrants may exercise the Warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement, and after the close of business on the expiration date, unexercised Warrants will become void.

Holders of the Warrants may exercise the Warrants by delivering the Warrant certificate representing the Warrants to be exercised together with specified information, and paying the required amount to the Warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We intend to set forth in any Warrant agreement or Warrant indenture and in the applicable prospectus supplement the information that the holder of the Warrant will be required to deliver to the Warrant agent.

Upon receipt of the required payment and any Warrant certificate or other form required for exercise properly completed and duly executed at the corporate trust office of the Warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the Common Shares purchasable upon such exercise. If fewer than all of the Warrants represented by the Warrant or Warrant certificate are exercised, then we will issue a new Warrant or Warrant certificate for the remaining amount of Warrants. If we so indicate in the applicable prospectus supplement, holders of the Warrants may surrender securities as all or part of the exercise price for Warrants.

As specified in the applicable prospectus supplement, we may issue units consisting of one or more of the following: Common Shares, Warrants or any combination of such securities. The applicable prospectus supplement will describe:

We may distribute the securities from time to time in one or more transactions at:

We will describe the method of distribution of each series of securities in the applicable prospectus supplement.

We may determine the price or other terms of the securities offered under this prospectus by use of an electronic auction. We will describe how any auction will determine the price or any other terms, how potential investors may participate in the auction and the nature of the underwriters’ obligations in the related supplement to this prospectus.

Underwriters, dealers or agents may receive compensation in the form of discounts, concessions or commissions from us or our purchasers as their agents in connection with the sale of the securities. These underwriters, dealers or agents may be considered to be underwriters under the Securities Act. As a result, discounts, commissions or profits on resale received by underwriters, dealers or agents may be treated as underwriting discounts and commissions. Each prospectus supplement will identify any underwriter, dealer or agent, and describe any compensation received by them from us. We may grant underwriters who participate in the distribution of securities an option to purchase additional securities to cover over-allotments, if any, in connection with the distribution.

We may have agreements with the underwriters, dealers and agents to indemnify them against specified civil liabilities, including liabilities under the Securities Act. Underwriters, dealers and agents may engage in transactions with or perform services for us in the ordinary course of their businesses.

To the extent required, this prospectus may be amended and supplemented from time to time to describe a specific plan of distribution.

We may designate agents who agree to use their reasonable efforts to solicit purchases of our securities for the period of their appointment or to sell our securities on a continuing basis.

If we use underwriters for a sale of securities, the underwriters will acquire the securities for their own account. The underwriters may resell the securities in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. The underwriters will be obligated to purchase all the securities of the series offered if they purchase any of the securities of that series. We may change from time to time any initial public offering price and any discounts or concessions the underwriters allow or reallow or pay to dealers. We may use underwriters with whom we have a material relationship. We will describe the nature of any such relationship in any prospectus supplement naming any such underwriter.

We may also sell securities directly to one or more purchasers without using underwriters or agents. Underwriters, dealers and agents that participate in the distribution of the securities may be underwriters as defined in the Securities Act, and any discounts or commissions they receive from us and any profit on their resale of the securities may be treated as underwriting discounts and commissions under the Securities Act. We will identify in the applicable prospectus supplement any underwriters, dealers or agents and will describe their compensation.

Unless otherwise specified in the applicable prospectus supplement, each class or series of securities will be a new issue with no established trading market, other than our Common Shares, which are listed on The Nasdaq Global Market. We may elect to list any other class or series of securities on any exchange or market, but we are not obligated to do so. It is possible that one or more underwriters may make a market in a class or series of securities, but the underwriters will not be obligated to do so and may discontinue any market making at any time without notice. We cannot give any assurance as to the liquidity of the trading market for any of the securities.

Any underwriter may engage in over-allotment, stabilizing transactions, short covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Over-allotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Short covering transactions involve purchases of the securities in the open market after the distribution is completed to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of these activities at any time.

If we so indicate in the prospectus supplement, we may authorize agents, underwriters or dealers to solicit offers from certain types of institutions to purchase securities from us at the public offering price under delayed delivery contracts. These contracts would provide for payment and delivery on a specified date in the future. The contracts would be subject only to those conditions described in the prospectus supplement. The prospectus supplement will describe the commission payable for solicitation of those contracts.

The validity of the securities in respect of which this prospectus is being delivered will be passed upon for us by Blake, Cassels & Graydon LLP, Vancouver, British Columbia, Canada, relating to matters of British Columbia or Canadian law, and Jones Day, relating to matters of New York or U.S. federal law. Additional legal matters may be passed upon for us or any underwriters, dealers or agents by counsel that we will name in the applicable prospectus supplement.

The consolidated financial statements of NioCorp Developments Ltd. as of June 30, 2023 and 2022 and for each of the three years in the period ended June 30, 2023, incorporated by reference in this prospectus and in the registration statement have been so incorporated in reliance on the report of BDO USA, P.C., an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting. The report on the consolidated financial statements contains an explanatory paragraph regarding NioCorp Developments Ltd.’s ability to continue as a going concern.

The financial statements of GX Acquisition Corp. II as of December 31, 2022 and 2021 and for the years ended December 31, 2022 and 2021, have been audited by Marcum LLP, an independent registered public accounting firm, as set forth in their report (which contains an explanatory paragraph relating to substantial doubt about the ability of GX Acquisition Corp. II to continue as a going concern as described in Note 1 to GXII’s financial statements), and are incorporated by reference in this prospectus and in the registration statement of which this prospectus is a part have been so incorporated in reliance on such report given upon such firm as experts in auditing and accounting.

The technical report summary for the Elk Creek Project prepared in accordance with subpart 1300 of Regulation S-K (the “S-K 1300 Elk Creek Technical Report Summary”), which is incorporated by reference in this prospectus, and the information summarized or quoted from the S-K 1300 Elk Creek Technical Report Summary included or incorporated by reference in this prospectus have been so included or incorporated by reference with the consent of the following qualified persons, as such term is defined in Item 1300 of Regulation S-K, who prepared the S-K 1300 Elk Creek Technical Report Summary and reviewed and approved such information summarized or quoted therefrom included or incorporated by reference in this prospectus: Dahrouge Geological Consulting USA Ltd.; Understood Mineral Resources Ltd.; Optimize Group; Tetra Tech; Adrian Brown Consultants Inc.; Metallurgy Concept Solutions; Magemi Mining Inc.; L3 Process Development; Olsson; A2GC; Scott Honan, M.Sc, SME-RM, NioCorp; Cementation; Mahmood Khwaja, P.E., CDM Smith; and Wynand Marx, M.Eng, BBE Consulting. A matrix of the sections of the S-K 1300 Elk Creek Technical Report Summary for which each qualified person is responsible is included in the S-K 1300 Elk Creek Technical Report Summary. Except for Scott Honan, none of the qualified persons is affiliated with NioCorp. Mr. Honan is the Chief Operating Officer of NioCorp.

The following table sets forth the fees and expenses payable by us in connection with the sale and distribution of the securities being registered hereby. All amounts are estimates, except for the Securities and Exchange Commission (“SEC”) registration fee:

* These fees and expenses are calculated based on the securities offered and the number of issuances and, accordingly, cannot be estimated at this time.

The corporate laws of British Columbia allow NioCorp Developments Ltd. (“we,” “us,” “our,” “NioCorp” or the “Company”), and its corporate articles require it (subject to the provisions of the British Columbia Business Corporations Act (“BCBCA”) noted below and the undertakings provided in Item 17 below), to indemnify its directors, former directors, alternate directors and their heirs and legal personal representatives against all eligible penalties to which such person is or may be liable, and NioCorp must, after the final disposition of an eligible proceeding, pay the expenses actually and reasonably incurred by such person in respect of that proceeding. Each director and alternate director is deemed to have contracted with NioCorp on the terms of the indemnity contained in NioCorp’s articles.

In addition, under the BCBCA, NioCorp may pay, as they are incurred in advance of the final disposition of an eligible proceeding, the expenses actually and reasonably incurred by an eligible party in respect of that proceeding, provided that NioCorp first receives from the eligible party a written undertaking that, if it is ultimately determined that the payment of expenses is prohibited by the restrictions noted below, the eligible party will repay the amounts advanced.

Notwithstanding the provisions of NioCorp’s articles noted above, NioCorp must not indemnify an eligible party or pay the expenses of an eligible party, if any of the following circumstances apply:

In addition, if an eligible proceeding is brought against an eligible party by or on behalf of NioCorp or by or on behalf of an associated corporation, NioCorp must not do either of the following:

Notwithstanding any of the foregoing, and whether or not payment of expenses or indemnification has been sought, authorized or declined under the BCBCA or the articles of NioCorp, on the application of NioCorp or an eligible party, the Supreme Court of British Columbia may do one or more of the following:

Furthermore, we have entered into an indemnification agreement with each of our directors and executive officers. The indemnification agreements provide that NioCorp will, to the fullest extent possible under applicable law, subject to other specified limitations, indemnify and hold harmless the directors and executive officers against any and all costs and expenses reasonably incurred for, or in connection with, any civil, criminal, administrative, investigative or other proceeding, whether threatened, pending, continuing or completed, including but not limited to any act, matter, deed or thing whatsoever made, done, committed, permitted or acquiesced in.

provided, however, that paragraphs (i), (ii) and (iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Securities and Exchange Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Centennial, State of Colorado, on June 13, 2024.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

KNOW ALL PERSONS BY THESE PRESENTS, that each of the directors and officers of the registrant whose signature appears below constitutes and appoints Mark A. Smith and Neal Shah, or either of them, as true and lawful attorneys-in-fact and agents with full power of substitution and re-substitution, for him and in his name, place and stead, in any and all capacities to sign the Registration Statement filed herewith and any or all amendments to said Registration Statement (including post-effective amendments and Registration Statements filed pursuant to Rule 462 and otherwise), and to file the same, with all exhibits thereto, and other documents in connection therewith, the Securities and Exchange Commission granting unto said attorney-in-fact and agents the full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the foregoing, as to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agents or any of them, or his substitute, may lawfully do or cause to be done by virtue hereof.

British Columbia, Canada (State or other jurisdiction of incorporation or organization)		98-1262185 (I.R.S. Employer Identification Number)

7000 South Yosemite Street, Suite 115 Centennial, Colorado 80112 Tel: (720) 334-7066 (Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

CT Corporation System 28 Liberty Street Floor 42 New York, New York 10005 Tel: (212) 894-8940 (Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies of all communications, including communications sent to agent for service, should be sent to:

Christopher M. Kelly Andrew C. Thomas Jones Day North Point 901 Lakeside Avenue Cleveland, Ohio 44114 (216) 586-3939	Bob Wooder Kyle Misewich Blake, Cassels & Graydon LLP 1133 Melville Street Suite 3500 Vancouver, British Columbia V6E 4E5

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

	Amount to be paid
SEC registration fee	$	29,520.00
Legal fees and expenses		*
Accounting fees and expenses		*
Printing expenses		*
Total	$	*

Exhibit No.		Title
1.1*		Form of Underwriting Agreement
4.1(1)		Notice of Articles of NioCorp Developments Ltd., dated April 5, 2016
4.2(1)		Articles of NioCorp Developments Ltd., as amended, effective as of January 27, 2015
4.3*		Form of Warrant Agreement
4.4*		Form of Warrant Indenture
4.5*		Form of Warrant Certificate
4.6*		Form of Unit Agreement
5.1		Opinion of Blake, Cassels & Graydon LLP
5.2		Opinion of Jones Day
23.1		Consent of Blake, Cassels & Graydon LLP (included in Exhibit 5.1)
23.2		Consent of Jones Day (included in Exhibit 5.2)
23.3		Consent of BDO USA, P.C.
23.4		Consent of Marcum LLP
23.5		Consent of Dahrouge Geological Consulting USA Ltd.
23.6		Consent of Understood Mineral Resources Ltd.
23.7		Consent of Optimize Group Inc.
23.8		Consent of Tetra Tech
23.9		Consent of Adrian Brown Consultants Inc.
23.10		Consent of Magemi Mining Inc.
23.11		Consent of L3 Process Development
23.12		Consent of Olsson
23.13		Consent of A2GC
23.14		Consent of Metallurgy Concept Solutions
23.15		Consent of Scott Honan, M.Sc., SME-RM, NioCorp
23.16		Consent of Cementation
23.17		Consent of Mahmood Khwaja, P.E., CDM Smith
23.18		Consent of Wynand Marx, M.Eng., BBE Consulting
24.1		Power of Attorney, contained on signature page hereto
96.1(2)		S-K 1300 Elk Creek Technical Report Summary
107		Filing Fee Table

	(1)	Previously filed as an exhibit to the Company’s Draft Registration Statement on Form S-1 (Registration No. 377-01354) submitted to the Securities and Exchange Commission on July 26, 2016 and incorporated herein by reference.
	(2)	Previously filed as an exhibit to the Company’s Annual Report on Form 10-K (File No. 000-55710) filed with the Securities and Exchange Commission on September 6, 2022 and incorporated herein by reference.
	*	To be filed by amendment or as an exhibit to a report pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended and incorporated herein by reference.

About This Prospectus	ii
Where You Can Find More Information	iii
Information Incorporated by Reference	iv
Summary	1
Risk Factors	2
Cautionary Note Regarding Forward-Looking Statements	3
Use of Proceeds	5
Description of Capital Stock	6
Description of Warrants	14
Description of Units	16
Plan of Distribution	17
Legal Matters	19
Experts	20

	NIOCORP DEVELOPMENTS LTD.


	By:	/s/ Mark A. Smith
		Mark A. Smith
		President and Chief Executive Officer (Principal Executive Officer)

/s/ Mark A. Smith	President, Chief Executive Officer (Principal	June 13, 2024
Mark A. Smith	Executive Officer and Authorized U.S. Representative)
	and Chairman of the Board of Directors

/s/ Neal Shah	Chief Financial Officer (Principal Financial and	June 13, 2024
Neal Shah	Accounting Officer)

/s/ Michael J. Morris	Director	June 13, 2024
Michael J. Morris

/s/ David C. Beling	Director	June 13, 2024
David C. Beling

/s/ Nilsa Guerrero-Mahon	Director	June 13, 2024
Nilsa Guerrero-Mahon

/s/ Peter Oliver	Director	June 13, 2024
Peter Oliver

/s/ Dean C. Kehler	Director	June 13, 2024
Dean C. Kehler

/s/ Michael G. Maselli	Director	June 13, 2024
Michael G. Maselli