UNITED STATES

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

(Amendment No. 1)*

Under the Securities Exchange Act of 1934

M3-Brigade Acquisition III Corp.

(Name of Issuer)

Class A Common Stock, par value $0.0001 per share

(Titles of Class of Securities)

552635104

(CUSIP Number)

December 31, 2023

(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)

The remainder of this cover page shall be filled out of a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended (the “Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 552635104

SCHEDULE 13G

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1	NAME OF REPORTING PERSON OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Cantor Fitzgerald Securities
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP	(a) ☐ (b) ☐
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION New York

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5	SOLE VOTING POWER 0
	6	SHARED VOTING POWER 0*
	7	SOLE DISPOSITIVE POWER 0
	8	SHARED DISPOSITIVE POWER 0*

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0*
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES	☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0.0%
12	TYPE OF REPORTING PERSON PN

FOOTNOTE:

Consists of 0 shares of common stock.

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SCHEDULE 13G

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1	NAME OF REPORTING PERSON OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Cantor Fitzgerald, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP	(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
	6	SHARED VOTING POWER 0*
	7	SOLE DISPOSITIVE POWER 0
	8	SHARED DISPOSITIVE POWER 0*

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0*
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES	☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0.0%
12	TYPE OF REPORTING PERSON PN

FOOTNOTES:

Consists of 0 shares of common stock.

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SCHEDULE 13G

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1	NAME OF REPORTING PERSON OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON CF Group Management, Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP	(a) ☐ (b) ☐
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION New York

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	5	SOLE VOTING POWER 0
	6	SHARED VOTING POWER 0*
	7	SOLE DISPOSITIVE POWER 0
	8	SHARED DISPOSITIVE POWER 0*

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0*
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES	☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0.0%
12	TYPE OF REPORTING PERSON CO

FOOTNOTES:

Consists of 0 shares of common stock.

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SCHEDULE 13G

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1	NAME OF REPORTING PERSON OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Howard W. Lutnick
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP	(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
	6	SHARED VOTING POWER 0*
	7	SOLE DISPOSITIVE POWER 0
	8	SHARED DISPOSITIVE POWER 0*

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0*
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES	☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 0.0%
12	TYPE OF REPORTING PERSON IN

FOOTNOTE:

Consists of 0 shares of common stock.

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SCHEDULE 13G

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Item 1(a).	Name of Issuer:

	M3-Brigade Acquisition III Corp.

Item 1(b).	Address of Issuer’s Principal Executive Offices:

	1700 Broadway, 19th Floor New York, New York 10019

Item 2(a).	Name of Person Filing:

	Cantor Fitzgerald Securities, Cantor Fitzgerald, L.P., CF Group Management, Inc. and Howard W. Lutnick (collectively, the “Reporting Persons”).
Item 2(b).	Address of Principal Business Office or, if none, Residence:

	110 East 59th Street New York, New York 10022
Item 2(c).	Citizenship:

	Cantor Fitzgerald Securities is a general partnership formed in New York. Cantor Fitzgerald, L.P. is a Delaware limited partnership, CF Group Management, Inc. is a New York corporation and Mr. Lutnick is a citizen of the United States of America.

Item 2(d).	Titles of Classes of Securities:

	Class A Common Stock, par value $0.0001 per share.

Item 2(e).	CUSIP Number:

	552635104

Item 3.

If This Statement is Filed Pursuant to Rule 13d-1(b), or 13d-2(b) or (c), Check Whether the Person Filing is a(n):

(a)	☐	Broker or dealer registered under Section 15 of the Exchange Act (15 U.S.C. 78o).
(b)	☐	Bank as defined in Section 3(a)(6) of the Exchange Act (15 U.S.C. 78c).
(c)	☐	Insurance company as defined in Section 3(a)(19) of the Exchange 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)	☐	Investment adviser in accordance with §240.13d-1(b)(1)(ii)(E).
(f)	☐	Employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F).
(g)	☐	Parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G).
(h)	☐	Savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813).
(i)	☐	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)	☐	Non-U.S. institution, in accordance with § 240.13d-1(b)(1)(ii)(J).
(k)	☐	Group in accordance with §240.13d-1(b)(1)(ii)(K).

If filing as a non-U.S. institution in accordance with §240. 13d-1(b)(1)(ii)(J), please specify the type of institution: ___________

CUSIP No. 552635104

SCHEDULE 13G

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Item 4.

Ownership

The responses to Items 5-11 of the cover pages of this Schedule 13G are incorporated herein by reference.

As of December 31, 2023, the Reporting Persons may be deemed to beneficially own an aggregate of 0 shares of Class A Common Stock, par value $0.0001 per share (“Common Stock”) of M3-Brigade Acquisition III Corp. (the “Issuer”), representing 0.0% of the Issuer’s outstanding Common Stock.

The percentage of the Common Stock held by the Reporting Persons is based on 30,000,000 shares of Common Stock outstanding as of August 18, 2023 as reported in the Issuer’s quarterly report on Form 10-Q filed with the Securities and Exchange Commission on August 18, 2023 and assumes no exercise of any warrants held by the Reporting Persons.

Cantor Fitzgerald Securities (“CFS”) was the record holder of the securities reported herein.

CF Group Management, Inc. is the managing general partner of Cantor Fitzgerald, L.P. (“Cantor”) and directly or indirectly controls the managing general partners of CFS. Mr. Lutnick is Chairman and Chief Executive of CF Group Management, Inc. (“CFGM”) and trustee of CFGM's sole stockholder. Cantor, indirectly, holds a majority of the ownership interests of CFS. As such, each of Cantor, CFGM and Mr. Lutnick may be deemed to have beneficial ownership of the securities directly held by CFS. Each such entity or person disclaims any beneficial ownership of the reported shares other than to the extent of any pecuniary interest they may have therein, directly or indirectly.

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SCHEDULE 13G

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Item 5.	Ownership of Five Percent or Less of a Class.

	If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following ☒.

Item 6.	Ownership of More than Five 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.

	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.	Certification.

By signing below the undersigned certifies that, to the best of his or its 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.

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SCHEDULE 13G

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SIGNATURE

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

Dated: February 12, 2024

CANTOR FITZGERALD SECURITIES

By:	/s/ Howard W. Lutnick
	Name:	Howard W. Lutnick
	Title:	Chief Executive Officer

CANTOR FITZGERALD, L.P.

By:	/s/ Howard W. Lutnick
	Name:	Howard W. Lutnick
	Title:	Chief Executive Officer

CF GROUP MANAGEMENT, INC.

By:	/s/ Howard W. Lutnick
	Name:	Howard W. Lutnick
	Title:	Chief Executive Officer

HOWARD W. LUTNICK

By:	/s/ Howard W. Lutnick
	Howard W. Lutnick

[Schedule 13G – M3-Brigade Acquisition III Corp. – February 2024]

CUSIP No. 552635104

SCHEDULE 13G

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Exhibit Index

Exhibit No.		Description
99.1		Joint Filing Agreement, dated as of February 12, 2024, by and among the Reporting Persons

M3-Brigade Acquisition III Corp. SC 13G/A