Mountain Lake (MLAAU) sponsor cancels 6,000 Class B founder shares

Rhea-AI Filing Summary

Mountain Lake Acquisition Corp. II reported a restructuring-related insider transaction involving its sponsor. Mountain Lake Acquisition Sponsor II LLC returned 6,000 Class B ordinary shares to the company for no consideration, and these shares were cancelled because the underwriters’ over-allotment option was not exercised in full.

The Class B ordinary shares automatically convert into Class A ordinary shares on a one-for-one basis at the initial business combination or earlier at the holder’s option, and they have no expiration date. CEO Paul Grinberg and CFO Douglas Horlick, as managing members of the sponsor, may be deemed beneficial owners of the sponsor’s Class B shares but disclaim beneficial ownership beyond their pecuniary interest.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Grinberg Paul, MOUNTAIN LAKE ACQUISITION SPONSOR II LLC, Horlick Douglas

Role CEO | 10% Owner | CFO

Type	Security	Shares	Price	Value
Other	Class B Ordinary Shares	6,000	$0.00	--

Holdings After Transaction: Class B Ordinary Shares — 12,000,000 shares (Direct)

Footnotes (1)

1. As described in the registration statement on Form S-1 (File No. 333-291833) of Mountain Lake Acquisition Corp. II (the "Issuer") under the heading "Description of Securities - Founder Shares," the Class B ordinary shares will automatically convert into Class A ordinary shares at the time of the Issuer's initial business combination, or at any time prior to the Issuer's initial business combination, at the option of the holder, on a one-for-one basis, subject to certain adjustments. The Class B ordinary shares have no expiration date. As contemplated in connection with the initial public offering of the Issuer, 6,000 Class B ordinary shares of the Issuer held by Mountain Lake Acquisition Sponsor II LLC (the "Sponsor") were returned to the Issuer for no consideration and cancelled because the underwriters' over-allotment option was not exercised in full. Paul Grinberg and Douglas Horlick are the managing members of the Sponsor and hold voting and investment discretion with respect to the Class B ordinary shares held of record by the Sponsor. As such, Messrs. Grinberg and Horlick may be deemed to have beneficial ownership of the securities held of record by the Sponsor. Messrs. Grinberg and Horlick disclaim any beneficial ownership except to the extent of their pecuniary interest therein.

Form 4 Insider Transactions: What Each Field Means →

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^*

Grinberg Paul

(Last) (First) (Middle)

930 TAHOE BLVD STE 802 PMB 45

(Street)

INCLINE VILLAGE NEVADA 89451

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Mountain Lake Acquisition Corp. II [ MLAAU ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/16/2026

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

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

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

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
Class B Ordinary Shares	(1)	03/16/2026		J(2)			6,000	(1)	(1)	Class A Ordinary Shares	6,000	$0	12,000,000(3)	D(3)

1. Name and Address of Reporting Person^*

Grinberg Paul

(Last) (First) (Middle)

930 TAHOE BLVD STE 802 PMB 45

(Street)

INCLINE VILLAGE NEVADA 89451

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

MOUNTAIN LAKE ACQUISITION SPONSOR II LLC

(Last) (First) (Middle)

930 TAHOE BLVD STE 802 PMB 45

(Street)

INCLINE VILLAGE NEVADA 89451

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

Horlick Douglas

(Last) (First) (Middle)

930 TAHOE BLVD STE 802 PMB 45

(Street)

INCLINE VILLAGE NEVADA 89451

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

Explanation of Responses:

1. As described in the registration statement on Form S-1 (File No. 333-291833) of Mountain Lake Acquisition Corp. II (the "Issuer") under the heading "Description of Securities - Founder Shares," the Class B ordinary shares will automatically convert into Class A ordinary shares at the time of the Issuer's initial business combination, or at any time prior to the Issuer's initial business combination, at the option of the holder, on a one-for-one basis, subject to certain adjustments. The Class B ordinary shares have no expiration date.

2. As contemplated in connection with the initial public offering of the Issuer, 6,000 Class B ordinary shares of the Issuer held by Mountain Lake Acquisition Sponsor II LLC (the "Sponsor") were returned to the Issuer for no consideration and cancelled because the underwriters' over-allotment option was not exercised in full.

3. Paul Grinberg and Douglas Horlick are the managing members of the Sponsor and hold voting and investment discretion with respect to the Class B ordinary shares held of record by the Sponsor. As such, Messrs. Grinberg and Horlick may be deemed to have beneficial ownership of the securities held of record by the Sponsor. Messrs. Grinberg and Horlick disclaim any beneficial ownership except to the extent of their pecuniary interest therein.

	/s/ Paul Grinberg	03/18/2026
	/s/ Paul Grinberg, Managing Member of Mountain Lake Acquisition Sponsor II LLC	03/18/2026
	/s/ Douglas Horlick	03/18/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did Mountain Lake Acquisition Corp. II (MLAAU) report?

Mountain Lake’s sponsor returned 6,000 Class B ordinary shares to the company for no consideration, and these shares were cancelled because the IPO underwriters’ over-allotment option was not fully exercised, making this a restructuring-type adjustment rather than a market trade.

How do Mountain Lake Acquisition Corp. II’s Class B shares convert into Class A shares?

Class B ordinary shares automatically convert into Class A ordinary shares on a one-for-one basis at the initial business combination, or earlier at the holder’s option, subject to adjustments. The filing also notes these Class B shares have no expiration date, defining their long-term structure.

Why were 6,000 Class B shares of Mountain Lake Acquisition Corp. II cancelled?

The 6,000 Class B ordinary shares held by the sponsor were returned to Mountain Lake for no consideration and cancelled because the IPO underwriters’ over-allotment option was not exercised in full, aligning the sponsor’s founder share allocation with the final IPO size.

Who may be deemed beneficial owners of Mountain Lake Acquisition Corp. II sponsor shares?

CEO Paul Grinberg and CFO Douglas Horlick are managing members of the sponsor and hold voting and investment discretion over its Class B shares. They may be deemed beneficial owners but explicitly disclaim beneficial ownership except to the extent of their pecuniary interest in those securities.

Does the reported Mountain Lake Acquisition Corp. II Form 4 involve open-market buying or selling?

No, the transaction is coded as an “other acquisition or disposition” and reflects sponsor-held shares returned to the issuer and cancelled. It does not represent open-market buying or selling activity and is categorized as a restructuring-type adjustment in the transaction summary.