UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): February 24, 2023

M3-BRIGADE ACQUISITION II CORP.

(Exact name of registrant as specified in its charter)

1700 Broadway, 19th Floor

New York, New York 10019

(Address of principal executive offices, including zip code)

(212) 202-2200

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Explanatory Note

This Form 8-K/A is filed by M3-Brigade Acquisition Corp. II (the “Company”) to amend and restate paragraph 1 of Item 1.01 of the Company’s Form 8-K filed with the Securities and Exchange Commission on February 24, 2023 (the “Form 8-K”).

Paragraph 1 of Item 1.01 of the Form 8-K is hereby amended and restated as follows:

On February 24, 2023, M3-Brigade Acquisition Corp. II (the “Company”) and M3-Brigade Sponsor II LP (the “Sponsor”) entered into a non-redemption agreement (“Non-Redemption Agreement”) with one or more unaffiliated third party or parties in exchange for such third party or third parties agreeing not to redeem an aggregate of 400,000 shares of the Company’s Class A common stock sold in its initial public offering (“Non-Redeemed Shares”) in connection with the special meeting of the stockholders called by the Company (the “Special Meeting”) to consider and approve an extension of time for the Company to consummate an initial business combination (the “Extension Proposal”) from March 8, 2023 to December 8, 2023 (the “Extension”). In exchange for the foregoing commitments not to redeem such Non-Redeemed Shares, the Sponsor has agreed to transfer to such third party or third parties an aggregate of 100,000 shares of the Company’s Class B common stock held by the Sponsor promptly upon consummation of the Extension if they continue to hold such Non-Redeemed Shares through the Special Meeting. Pursuant to the Underwriting Agreement, dated as of March 3, 2021, by and between the Company and Cantor Fitzgerald & Co. (“Cantor Fitzgerald”), which was filed as Exhibit 1.1 to the Company’s Form 8-K filed with the Securities and Exchange Commission on March 9, 2021, Cantor Fitzgerald has consented in writing to the transfers of the Company’s Class B common stock contemplated by the Non-Redemption Agreements. The Sponsor intends to enter into additional Non-Redemption Agreements prior to the Special Meeting.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

-2-