[SCHEDULE 13G] NioCorp Developments Ltd. SEC Filing

Rhea-AI Filing Summary

Citadel entities and founder Kenneth Griffin have crossed the 5 % ownership threshold in NioCorp Developments Ltd. (NB) and therefore filed this Schedule 13G.

The filing discloses aggregated beneficial ownership of 3,903,395 common shares, equal to ≈5.4 % of the 72.65 million shares outstanding as cited in NioCorp’s 18 Jul 2025 prospectus. Within this total, Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC jointly report 3,772,972 shares (5.2 %), while Citadel Securities controls 130,423 shares (0.2 %). All voting and dispositive powers are shared; no party reports sole power.

The position is reported under Rule 13d-1(b), signalling a passive investment. Certification language states the shares were “not acquired … to change or influence control.” The stake includes 69 shares issuable upon warrant conversion.

This is Citadel’s first publicly reported ownership above the 5 % threshold in NB, potentially indicating incremental institutional interest, but the filing provides no operational or financial commentary.

Positive

• Citadel and Kenneth Griffin now hold a 5.4 % stake, introducing a high-profile institutional owner.
• Market-making presence of Citadel Securities may enhance trading liquidity for NB shares.

Negative

• Stake is filed on Schedule 13G, indicating no activist or strategic intent—limited catalyst potential.
• Ownership remains relatively small versus total float, limiting Citadel’s influence on corporate decisions.

Insights

Securities Analyst

TL;DR – Citadel’s 5.4 % passive stake modestly boosts institutional credibility and liquidity for NB.

Crossing the 5 % line obliges disclosure, but the scale—3.9 M shares—remains modest versus NioCorp’s 72.6 M float. Citadel’s multi-strategy funds hold 5.2 %, while its market-making arm retains 0.2 %, suggesting both investment and trading interests. Because the filing is on Form 13G, it denotes passive intent, reducing probability of activist pressure. Still, Citadel’s reputation can attract other institutions, narrow bid-ask spreads via Citadel Securities, and potentially lower the company’s cost of capital. Absent earnings data, the stake is modestly positive but not transformational.

Corporate Governance Expert

TL;DR – Passive filing signals no governance agenda; control dynamics unchanged.

A 13G, unlike a 13D, conveys that Citadel and Griffin have no present intention to influence strategy or board composition. All powers are shared and there is zero sole voting authority. At 5.4 %, the group cannot single-handedly dictate outcomes and would need alliances to effect change. Therefore, shareholders should not expect near-term governance shifts. The filing does, however, establish a public baseline; if Citadel later increases or changes intent, new disclosures would be required within mandated timeframes. Impact is neutral for control considerations.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

NioCorp Developments Ltd.

(Name of Issuer)

Common Shares, without par value (the "Shares")

(Title of Class of Securities)

654484609

(CUSIP Number)

07/18/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 654484609

1

Names of Reporting Persons

Citadel Advisors LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 3,772,972.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 3,772,972.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,772,972.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.2 %

12

Type of Reporting Person (See Instructions)

IA, HC, OO

Comment for Type of Reporting Person: The percentages reported in this Schedule 13G are based upon 72,649,342 Shares outstanding comprised of (i) 72,649,273 Shares outstanding as of July 15, 2025 (according to the issuer's prospectus as filed with the Securities and Exchange Commission on July 18, 2025), and (ii) 69 Shares issuable upon conversion of certain warrants held by affiliates of the reporting persons. Except as described in the preceding sentence, all Shares for the holdings of the reporting persons reported in this Schedule 13G are as of the opening of the market on July 25, 2025.

SCHEDULE 13G

CUSIP No. 654484609

1

Names of Reporting Persons

Citadel Advisors Holdings LP

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 3,772,972.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 3,772,972.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,772,972.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.2 %

12

Type of Reporting Person (See Instructions)

HC, PN

SCHEDULE 13G

CUSIP No. 654484609

1

Names of Reporting Persons

Citadel GP LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 3,772,972.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 3,772,972.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,772,972.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.2 %

12

Type of Reporting Person (See Instructions)

HC, OO

SCHEDULE 13G

CUSIP No. 654484609

1

Names of Reporting Persons

Citadel Securities LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 130,423.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 130,423.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

130,423.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

0.2 %

12

Type of Reporting Person (See Instructions)

BD, OO

SCHEDULE 13G

CUSIP No. 654484609

1

Names of Reporting Persons

Citadel Securities Group LP

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 130,423.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 130,423.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

130,423.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

0.2 %

12

Type of Reporting Person (See Instructions)

HC, PN

SCHEDULE 13G

CUSIP No. 654484609

1

Names of Reporting Persons

Citadel Securities GP LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 130,423.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 130,423.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

130,423.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

0.2 %

12

Type of Reporting Person (See Instructions)

HC, OO

SCHEDULE 13G

CUSIP No. 654484609

1

Names of Reporting Persons

Kenneth Griffin

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 3,903,395.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 3,903,395.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,903,395.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.4 %

12

Type of Reporting Person (See Instructions)

HC, IN

SCHEDULE 13G

Item 1.
(a)	Name of issuer: NioCorp Developments Ltd.
(b)	Address of issuer's principal executive offices: 7000 South Yosemite Street, Suite 115 Centennial, CO, 80112
Item 2.
(a)	Name of person filing: 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 (Ireland) Designated Activity Company, an Ireland 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 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).
(b)	Address or principal business office or, if none, residence: The address of each of the Reporting Persons is 830 Brickell Plaza, Miami, Florida 33131.
(c)	Citizenship: 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.
(d)	Title of class of securities: Common Shares, without par value (the "Shares")
(e)	CUSIP No.: 654484609
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may be deemed to beneficially own 3,772,972 Shares. 2. Citadel Securities LLC may be deemed to beneficially own 130,423 Shares. 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC may be deemed to beneficially own 130,423 Shares. 4. Mr. Griffin may be deemed to beneficially own 3,903,395 Shares.
(b)	Percent of class: 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 5.2% of the Shares outstanding. 2. The number of Shares that Citadel Securities LLC may be deemed to beneficially own constitutes 0.2% 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 0.2% of the Shares outstanding. 4. The number of Shares that Mr. Griffin may be deemed to beneficially own constitutes 5.4% of the Shares outstanding.
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 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
	(ii) Shared power to vote or to direct the vote: 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 3,772,972 2. Citadel Securities LLC: 130,423 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 130,423 4. Mr. Griffin: 3,903,395
	(iii) Sole power to dispose or to direct the disposition of: 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
	(iv) Shared power to dispose or to direct the disposition of: 1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 3,772,972 2. Citadel Securities LLC: 130,423 3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 130,423 4. Mr. Griffin: 3,903,395
Item 5.	Ownership of 5 Percent or Less of a Class.
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

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.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Citadel Advisors LLC

Signature:	/s/ Seth Levy
Name/Title:	Seth Levy, Authorized Signatory
Date:	07/25/2025

Citadel Advisors Holdings LP

Signature:	/s/ Seth Levy
Name/Title:	Seth Levy, Authorized Signatory
Date:	07/25/2025

Citadel GP LLC

Signature:	/s/ Seth Levy
Name/Title:	Seth Levy, Authorized Signatory
Date:	07/25/2025

Citadel Securities LLC

Signature:	/s/ Seth Levy
Name/Title:	Seth Levy, Authorized Signatory
Date:	07/25/2025

Citadel Securities Group LP

Signature:	/s/ Seth Levy
Name/Title:	Seth Levy, Authorized Signatory
Date:	07/25/2025

Citadel Securities GP LLC

Signature:	/s/ Seth Levy
Name/Title:	Seth Levy, Authorized Signatory
Date:	07/25/2025

Kenneth Griffin

Signature:	/s/ Seth Levy
Name/Title:	Seth Levy, attorney-in-fact*
Date:	07/25/2025

Comments accompanying signature: * 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.

Exhibit Information

Exhibit 99.1 - Joint Filing Agreement

FAQ

Why did Citadel file a Schedule 13G on NioCorp (NB)?

Citadel entities and Kenneth Griffin exceeded the 5 % ownership threshold, triggering the passive reporting requirement under Rule 13d-1(b).

How many NioCorp shares does Citadel now own?

Citadel Advisors–related entities report 3,772,972 shares; Citadel Securities holds 130,423 shares, for a combined 3,903,395 shares including warrants.

What percentage of NioCorp’s outstanding shares is held by Kenneth Griffin?

Griffin is deemed to beneficially own 5.4 % of outstanding shares.

Does the filing indicate activist intentions by Citadel?

No. A Schedule 13G denotes a passive investment; the certification states the shares were not acquired to influence control.

When were the share counts calculated?

Holdings are as of the market open on 25 Jul 2025, using NioCorp’s outstanding share count disclosed 18 Jul 2025.

Where is NioCorp’s outstanding share count sourced?

The figure of 72,649,342 shares comes from NioCorp’s prospectus filed with the SEC on 18 Jul 2025.