Mr. Jim Sims reports

NIOCORP GRANTED MANAGEMENT CEASE TRADE ORDER

Niocorp Developments Ltd.'s principal regulator, the Ontario Securities Commission (OSC), has approved the company's application for, and has granted, a management cease trade order (MCTO).

As previously announced on Sept. 26, 2023, Niocorp applied for the MCTO due to the anticipated delay in filing its annual financial statements for the year ended June 30, 2023, the related management's discussion and analysis, and the chief executive officer and chief financial officer certifications relating to the annual financial statements (collectively, the required documents) before the Sept. 28, 2023, deadline. The closing of the company's previously announced business combination with GX Acquisition Corp. II, and the continuing complexities in integrating GX and accounting for the business combination resulted in the delay in filing the required documents.

The MCTO restricts all trading in securities of the company by Niocorp's chief executive officer and chief financial officer until such time as the required documents have been filed by the company and the MCTO has been revoked. The MCTO does not generally affect the ability of other shareholders of the company or the general investing public to trade in the company's securities.

The company confirms that it will comply with the provisions of the alternative information guidelines under National Policy 12-203 -- Management Cease Trade Orders by issuing biweekly default status reports in the form of news releases for as long as the required documents have not been filed. The company confirms that there is no material information concerning the affairs of the company that has not been generally disclosed as of the date of this press release.

In addition, as a United States Securities and Exchange Commission (SEC) reporting issuer, Niocorp filed a Form 12b-25 notice of late filing with the SEC on Sept. 29, 2023, to provide for an extension to file its annual report on Form 10-K through Oct. 13, 2023.

Pursuant to the MCTO, Niocorp will have until Nov. 28, 2023, to file the required documents with the applicable Canadian regulatory authorities. Niocorp's management is working diligently to remedy the situation and anticipates filing the required documents prior to the filing deadline.

Niocorp intends to provide updates on further developments in respect of this matter promptly following their occurrence.

About Niocorp Developments Ltd.

Niocorp is developing a critical mineral project in southeast Nebraska that is expected to produce niobium, scandium and titanium subject to the receipt of sufficient project financing. The company also is evaluating the potential to produce several rare earths from the Elk Creek project. Niobium is used to produce specialty alloys, as well as high-strength, low-alloy steel, which is a lighter, stronger steel used in automotive, structural and pipeline applications. Scandium is a specialty metal that can be combined with aluminum to make alloys with increased strength and improved corrosion resistance. Scandium is also a critical component of advanced solid oxide fuel cells. Titanium is used in various lightweight alloys, is a key component of pigments used in paper, paint and plastics, and is also used for aerospace applications, armour and medical implants. Magnetic rare earths, such as neodymium, praseodymium, terbium and dysprosium, are critical to the making of neodymium-iron-boron magnets, which are used across a wide variety of defence and civilian applications.

We seek Safe Harbor.