Atlantic Coastal Acquisition Corp. II(ACABU) - Prospectus(update)

As filed with the U.S. Securities and Exchange Commission on November 28, 2025 Registration No. 333-291347 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 AMENDMENT NO. 1 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Abpro Holdings, Inc. (Exact Name of Registrant as Specified in its Charter) (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) Delaware 2834 87-1013956 (I.R.S. Employer Identificat ...