As filed with the Securities and Exchange Commission on May 1, 2024. Registration No. 333-278192 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Churchill Capital Corp IX (Exact Name of Registrant as Specified in its Charter) Cayman Islands 6770 86-1885237 (State or Other Jurisdiction of Incorporation or Organization) (Primary Standard Industrial Classification Code Number) (IRS Employer Identification Number) 640 Fifth Avenue, 14th Floor New York, NY 10019 Telephone: (212) 380-7500 (Addres ...