NIOCORP DEVELOPMENTS LTD

Disclosure Controls and Procedures

The management of NioCorp Developments Ltd. has evaluated, under the supervision of and with the participation of the Chief Executive Officer (“CEO”) and the Chief Financial Officer (“CFO”), the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of September 30, 2026. Based on that evaluation, the CEO and the CFO have concluded that, as of September 30, 2026, our disclosure controls and procedures were not effective due to the material weakness in internal control over financial reporting described below.

Notwithstanding the material weakness in our internal control over financial reporting, our CEO and CFO have concluded that the interim condensed consolidated financial statements included in this Quarterly Report on Form 10-Q fairly present, in all material respects, our financial position, results of operations and cash flows for the periods presented in conformity with U.S. GAAP.

Material Weakness in Internal Control over Financial Reporting

As previously disclosed in Part II, Item 9A, “Controls and Procedures,” of our Annual Report on Form 10-K, management identified a material weakness in our internal control over financial reporting, as defined in Rules 13a-15(f) and 15d-15(f) of the Exchange Act, which is described below.

Material Weakness

A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of our annual or interim consolidated financial statements will not be prevented or detected on a timely basis.

Management concluded that the one material weakness disclosed in the Company’s Annual Report on Form 10-K continued to exist as of September 30, 2026. That material weakness relates to a deficiency in the principles associated with the control activities component of internal control, based on the criteria set forth in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission:

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Control Activities: Management did not maintain effective controls over the design and implementation of process-level control activities related to vendor banking information.

The material weakness described above could result in a misstatement of account balances or disclosures that would result in a material misstatement to the annual or interim consolidated financial statements that would not be prevented or timely detected. The material weakness did not result in any misstatement of the Company’s consolidated financial statements.

Remediation Plan

To address the material weakness existing as of September 30, 2026 described above, we are continuing to implement a remediation plan. These actions include the following:

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We have designed and implemented process-level controls over the initiation, verification, approval and recording of changes to vendor banking information, including independent verification of each change request through a call-back or comparable out-of-band confirmation to a previously validated contact, segregation of duties between the requestor and the approver of changes to vendor data, and periodic management review of a system-generated report of all changes to vendor master data.

The process of designing and maintaining effective internal control over financial reporting is a continuous effort that requires management to anticipate and react to changes in our business, economic and regulatory environments and to expend significant resources. As we continue to evaluate our internal control over financial reporting, we may take additional actions to remediate the material weakness or modify the remediation actions described above.

While we continue to devote significant time and attention to these remediation efforts, the material weakness will not be considered remediated until the controls operate for a sufficient period of time, and management has concluded, through testing, that these controls are effective. Management currently expects to complete these actions during fiscal year 2027.

Changes in Internal Control over Financial Reporting

Other than as discussed above, there has been no change in our internal control over financial reporting during the quarter ended September 30, 2026, that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.