NIOCORP DEVELOPMENTS LTD — Major Shareholding Notification 2025

Nov 14, 2025

xml version="1.0" encoding="UTF-8"? SCHEDULE 13G/A 0001104659-25-070922 Field: Pseudo-Tag; ID: Name; Data: CITADEL ADVISORS LLC 0001423053 XXXXXXXX LIVE 1 Common Shares, without par value (the "Shares") 09/30/2025 0001512228 NioCorp Developments Ltd. 654484609 7000 South Yosemite Street, Suite 115 Centennial CO 80112 Rule 13d-1(c) Citadel Advisors LLC DE 0.00 7606069.00 0.00 7606069.00 7606069.00 N 7.9 IA HC OO The percentages reported in this Schedule 13G are based upon 96,499,877 Shares outstanding as of September 26, 2025 (according to the issuer's prospectus as filed with the Securities and Exchange Commission on September 29, 2025). Citadel Advisors Holdings LP DE 0.00 7606069.00 0.00 7606069.00 7606069.00 N 7.9 HC PN Citadel GP LLC DE 0.00 7606069.00 0.00 7606069.00 7606069.00 N 7.9 HC OO Citadel Securities LLC DE 0.00 345182.00 0.00 345182.00 345182.00 N 0.4 BD OO Citadel Securities Group LP DE 0.00 345182.00 0.00 345182.00 345182.00 N 0.4 HC PN Citadel Securities GP LLC DE 0.00 345182.00 0.00 345182.00 345182.00 N 0.4 HC OO Kenneth Griffin X1 0.00 7951251.00 0.00 7951251.00 7951251.00 N 8.2 HC IN NioCorp Developments Ltd. 7000 South Yosemite Street, Suite 115, Centennial, CO, 80112 This Schedule 13G is being jointly filed by Citadel Advisors LLC ("Citadel Advisors"), Citadel Advisors Holdings LP ("CAH"), Citadel GP LLC ("CGP"), Citadel Securities LLC ("Citadel Securities"), Citadel Securities Group LP ("CALC4"), Citadel Securities GP LLC ("CSGP") and Mr. Kenneth Griffin (collectively with Citadel Advisors, CAH, CGP, Citadel Securities, CALC4 and CSGP, the "Reporting Persons") with respect to the Shares of the above-named issuer owned by Citadel Multi-Strategy Equities Master Fund Ltd., a Cayman Islands company ("CM"), Citadel Multi-Strategy Equities (Ireland) DAC, an Ireland designated activity company ("CMSI"), and Citadel Securities. Such owned Shares may include other instruments exercisable for or convertible into Shares. Citadel Advisors is the portfolio manager for CM and CMSI. CAH is the sole member of Citadel Advisors. CGP is the general partner of CAH. CALC4 is the non-member manager of Citadel Securities. CSGP is the general partner of CALC4. Mr. Griffin is the President and Chief Executive Officer of CGP, and owns a controlling interest in CGP and CSGP. The filing of this statement shall not be construed as an admission that any of the Reporting Persons is the beneficial owner of any securities covered by the statement other than the securities actually owned by such person (if any). The address of each of the Reporting Persons is 830 Brickell Plaza, Miami, Florida 33131. Each of Citadel Advisors, CGP, Citadel Securities and CSGP is organized as a limited liability company under the laws of the State of Delaware. Each of CALC4 and CAH is organized as a limited partnership under the laws of the State of Delaware. Mr. Griffin is a U.S. citizen. Y 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may be deemed to beneficially own 7,606,069 Shares. 2. Citadel Securities LLC may be deemed to beneficially own 345,182 Shares. 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC may be deemed to beneficially own 345,182 Shares. 4. Mr. Griffin may be deemed to beneficially own 7,951,251 Shares. 1. The number of Shares that each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may be deemed to beneficially own constitutes 7.9% of the Shares outstanding. 2. The number of Shares that Citadel Securities LLC may be deemed to beneficially own constitutes 0.4% of the Shares outstanding. 3. The number of Shares that each of Citadel Securities Group LP and Citadel Securities GP LLC may be deemed to beneficially own constitutes 0.4% of the Shares outstanding. 4. The number of Shares that Mr. Griffin may be deemed to beneficially own constitutes 8.2% of the Shares outstanding. 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 0 2. Citadel Securities LLC: 0 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 0 4. Mr. Griffin: 0 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 7,606,069 2. Citadel Securities LLC: 345,182 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 345,182 4. Mr. Griffin: 7,951,251 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 0 2. Citadel Securities LLC: 0 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 0 4. Mr. Griffin: 0 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 7,606,069 2. Citadel Securities LLC: 345,182 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 345,182 4. Mr. Griffin: 7,951,251 Y Y Y Y Y N By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. Citadel Advisors LLC /s/ Seth Levy Seth Levy, Authorized Signatory 11/14/2025 Citadel Advisors Holdings LP /s/ Seth Levy Seth Levy, Authorized Signatory 11/14/2025 Citadel GP LLC /s/ Seth Levy Seth Levy, Authorized Signatory 11/14/2025 Citadel Securities LLC /s/ Seth Levy Seth Levy, Authorized Signatory 11/14/2025 Citadel Securities Group LP /s/ Seth Levy Seth Levy, Authorized Signatory 11/14/2025 Citadel Securities GP LLC /s/ Seth Levy Seth Levy, Authorized Signatory 11/14/2025 Kenneth Griffin /s/ Seth Levy Seth Levy, attorney-in-fact* 11/14/2025 * Seth Levy is signing on behalf of Kenneth Griffin as attorney-in-fact pursuant to a power of attorney previously filed with the Securities and Exchange Commission, and hereby incorporated by reference herein. The power of attorney was filed as an attachment to a filing by Citadel Advisors LLC on Schedule 13G for Allakos Inc. on October 13, 2023.