Churchill Capital Corp IX — Current Report (Form 8-K)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): December 2, 2025

CHURCHILL CAPITAL CORP IX

(Exact name of registrant as specified in its charter)

640 Fifth Avenue, 14th Floor

New York, NY 10019

(Address of principal executive offices, including zip code)

Registrant’s telephone number, including area code: (212) 380-7500

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. ☐

Item 1.01 Entry into a Material Definitive Agreement

On December 2, 2025, Churchill Capital Corp IX (the “Company”) issued an unsecured promissory note (the “Note”) in the aggregate principal amount of up to $1,500,000 to Churchill Sponsor IX LLC (the “Sponsor”), the Company’s sponsor, for the Company’s working capital needs. The Note does not bear interest and matures upon the earlier of the closing of an initial business combination by the Company and the Company’s liquidation.

Amounts outstanding under the Note are convertible, at the option of the Sponsor, into units of the Company (the “Conversion Units”), at a conversion price of $10.00 per Conversion Unit, with each unit consisting of one share of the Company’s Class A ordinary share, par value $0.0001 per share (“Class A Ordinary Share”), and one-quarter of one warrant, with each whole warrant exercisable for one Class A Ordinary Share at $11.50 per share, subject to adjustment as provided in the Company’s Registration Statement on Form S-1 filed in connection with its initial public offering (“IPO”). The Conversion Units will be identical to the private placement units issued to the Sponsor at the time of the Company’s IPO. The Conversion Units are entitled to registration rights.

The foregoing description of the Note is qualified in its entirety by reference to the full text of the Note, which is filed with this Current Report on Form 8-K as Exhibit 10.1 and is incorporated herein by reference.

Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

The disclosure contained in Item 1.01 of this Current Report on Form 8-K is incorporated by reference in this Item 2.03.

Item 9.01. Financial Statements and Exhibits

(c) Exhibits:

SIGNATURE

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