[Form 4] NioCorp Developments Ltd. Insider Trading Activity

Rhea-AI Filing Summary

NioCorp Developments Ltd. director Nilsa Guerrero-Mahon was granted a director stock option on 08/18/2025 to purchase 55,000 common shares at an exercise price of $4.35 per share. The filing states 34% of the options vested on the grant date and the remainder vests in equal installments on each anniversary of the grant date until August 18, 2027. The option term appears to expire in 2030 and is reported as directly owned by the reporting person. The Form 4 was signed by an attorney-in-fact on 08/20/2025.

Positive

• 55,000 options granted to director Nilsa Guerrero-Mahon at an exercise price of $4.35
• 34% of options vested immediately, with remaining vesting in equal annual installments through August 18, 2027

Negative

• None.

Insights

Securities Analyst

TL;DR: Director granted 55,000 options at $4.35 with partial immediate vesting and staged annual vesting through 2027.

The grant provides management-level compensation through equity-based incentives. Key specifics are the 55,000 option size, the $4.35 strike price, immediate vesting of 34% and the remaining vesting in equal annual installments until August 18, 2027. The reported ownership is direct and the option term extends to 2030. For investors, this is a routine insider grant disclosure rather than a market-moving transaction; it documents alignment of a director’s interests with shareholders via equity.

Corporate Governance Expert

TL;DR: Typical director equity award with staged vesting; disclosure complies with Section 16 reporting.

The Form 4 clearly reports the grant mechanics: grant date 08/18/2025, 34% vested immediately, remaining vesting on annual anniversaries through 08/18/2027, and a total of 55,000 options exercisable at $4.35. The filing is signed by an attorney-in-fact and lists the reporting person as a director. The disclosure meets the technical requirements for changes in beneficial ownership and provides the necessary vesting schedule information for governance review.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Guerrero-Mahon Nilsa

(Last) (First) (Middle)

C/O NIOCORP DEVELOPMENTS LTD.

7000 YOSEMITE STREET, SUITE 115

(Street)

CENTENNIAL CO 80112

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
NIOCORP DEVELOPMENTS LTD [ NB ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
08/18/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Director Stock Option (Right to Buy)	$4.35	08/18/2025		A		55,000		(1)	08/19/2030	Common Shares	55,000	$0	55,000	D

Explanation of Responses:

1. 34% of the options vested on the grant date and the remainder will vest in equal installments on each anniversary of the grant date until August 18, 2027.

	/s/ Neal S. Shah, as attorney-in-fact	08/20/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did NioCorp (NB) report on the Form 4 filed for Nilsa Guerrero-Mahon?

The Form 4 reports a grant of 55,000 director stock options on 08/18/2025 with an exercise price of $4.35.

How much of the option grant vested immediately for the director?

34% of the options vested on the grant date, with the remainder vesting in equal annual installments until August 18, 2027.

What is the ownership form reported for the granted options?

The filing reports the options as direct (D) beneficial ownership by the reporting person.

When was the Form 4 executed and filed?

The Form 4 shows the transaction date 08/18/2025 and was signed by an attorney-in-fact on 08/20/2025.

What is the expiration timeframe shown for the options?

The filing indicates the option term extends to 2030 (the document shows an expiration in 2030 associated with the grant).