NioCorp Set to Be Added to the Russell 3000 Index

CENTENNIAL, May 24, 2023 - NioCorp Developments Ltd. ("NioCorp" or the "Company") (NASDAQ:NB) (TSX:NB) is pleased to announce that it is set to join the broad-market Russell 3000 Index at the conclusion of the 2023 Russell indexes annual reconstitution, effective after the US market opens on June 26, 2023, according to a preliminary list of additions posted May 19, 2023.

Annual Russell indexes reconstitution captures the 4,000 largest US stocks as of April 28, ranking them by total market capitalization. Membership in the US all-cap Russell 3000 Index, which remains in place for one year, means automatic inclusion in the large-cap Russell 1000 Index or small-cap Russell 2000 Index, as well as the appropriate growth and value style indexes. FTSE Russell determines membership for its Russell indexes primarily through objective, market-capitalization rankings and style attributes. Overall, more than $12.1 trillion in investor assets track the Russell indexes, and 69% of actively managed US equity institutional assets are benchmarked to a Russell US Index.

"Being added to the Russell 3000 is another big step forward for NioCorp, after uplisting to the Nasdaq, and we believe it will significantly raise NioCorp's global visibility with institutional investment firms that have index funds that track Russell indexes," said Mark A. Smith, NioCorp CEO and Executive Chairman.

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FOR MORE INFORMATION:
Jim Sims, Corporate Communications Officer, NioCorp Developments Ltd., 720-639-4650, jim.sims@niocorp.com

@NioCorp $NB $NB.TO #niobium #scandium #titanium #rareearths #neodymium #praseodymium #dysprosium #terbium @FTSERussell #RussellRecon

ABOUT NIOCORP

NioCorp is developing a critical minerals project in Southeast Nebraska that will produce niobium, scandium, and titanium. The Company also is evaluating the potential to produce several rare earths from the Project. Niobium is used to produce specialty alloys as well as High Strength, Low Alloy ("HSLA") 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 and is a key component of pigments used in paper, paint and plastics and is also used for aerospace applications, armor, and medical implants. Magnetic rare earths, such as neodymium, praseodymium, terbium, and dysprosium are critical to the making of Neodymium-Iron-Boron ("NdFeB") magnets, which are used across a wide variety of defense and civilian applications.

ABOUT FTSE RUSSELL

FTSE Russell is a global index leader that provides innovative benchmarking, analytics and data solutions for investors worldwide. FTSE Russell calculates thousands of indexes that measure and benchmark markets and asset classes in more than 70 countries, covering 98% of the investable market globally. FTSE Russell index expertise and products are used extensively by institutional and retail investors globally. Approximately $20.1 trillion is currently benchmarked to FTSE Russell indexes. For over 30 years, leading asset owners, asset managers, ETF providers and investment banks have chosen FTSE Russell indexes to benchmark their investment performance and create ETFs, structured products and index-based derivatives. A core set of universal principles guides FTSE Russell index design and management: independent committees of leading market participants inform a transparent rules-based methodology. FTSE Russell is focused on applying the highest industry standards in index design and governance and embraces the IOSCO Principles. FTSE Russell is also focused on index innovation and customer partnerships as it seeks to enhance the breadth, depth and reach of its offering. FTSE Russell is wholly owned by London Stock Exchange Group. For more information, visit www.ftserussell.com.

FORWARD-LOOKING STATEMENTS
This press release contains forward-looking statements within the meaning of the United States Private Securities Litigation Reform Act of 1995 and forward-looking information within the meaning of applicable Canadian securities laws. Forward-looking statements may include, but are not limited to, statements about NioCorp's expection that it will be added to the Russell 3000 index and investment from institutional investors. Forward-looking statements are typically identified by words such as "plan," "believe," "expect," "anticipate," "intend," "outlook," "estimate," "forecast," "project," "continue," "could," "may," "might," "possible," "potential," "predict," "should," "would" and other similar words and expressions, but the absence of these words does not mean that a statement is not forward-looking.

The forward-looking statements are based on the current expectations of the management of NioCorp and are inherently subject to uncertainties and changes in circumstances and their potential effects and speak only as of the date of such statement. There can be no assurance that future developments will be those that have been anticipated. Forward-looking statements reflect material expectations and assumptions. Such expectations and assumptions are inherently subject to uncertainties and contingencies regarding future events and, as such, are subject to change. Forward-looking statements involve a number of risks, uncertainties or other factors that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to, those discussed and identified in public filings made by NioCorp with the SEC and with the applicable Canadian securities regulatory authorities and the following: NioCorp's ability to operate as a going concern; NioCorp's requirement of significant additional capital; NioCorp's limited operating history; NioCorp's history of losses; 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; current and future off take agreements, joint ventures, and partnerships; NioCorp's ability to attract qualified management; the effects of the COVID-19 pandemic or other 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; changes in demand for and price of commodities (such as fuel and electricity) and currencies; changes or disruptions in the securities markets; legislative, political or economic developments; the need to obtain permits and comply with laws and regulations and other regulatory requirements; 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 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 any of the assumptions made by the management of NioCorp prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements.

All subsequent written and oral forward-looking statements concerning the matters addressed herein and attributable to NioCorp or any person acting on its behalf are expressly qualified in their entirety by the cautionary statements contained or referred to herein. Except to the extent required by applicable law or regulation, NioCorp undertakes no obligation to update these forward-looking statements to reflect events or circumstances after the date hereof to reflect the occurrence of unanticipated events.

SOURCE: NioCorp Developments Ltd.