X0202 SCHEDULE 13D/A 0002147714 XXXXXXXX LIVE 1 Class A Ordinary Shares, $0.0001 par value 09/21/2026 false 0002123955 G7115W109 Pinnacle Acquisition Corporation

375 South County Road, Suite 220 Palm Beach FL 33480

Steven K. Hudson (561) 309-3447 375 South County Road, Suite 220 Palm Beach FL 33480 0002147714 N Steven Kenneth Hudson PF N X1 1250000.00 5225000.00 1250000.00 5225000.00 6475000.00 N 25.67 IN (1) Includes 225,000 of the Issuer's Class A ordinary shares, $0.0001 par value ("Class A Ordinary Shares") and 5,000,000 of the Issuer's Class B ordinary shares, $0.0001 par value ("Class B Ordinary Shares" and, together with the Class A Ordinary Shares, the "Ordinary Shares"), which are automatically convertible into Class A Ordinary Shares at the time of the Issuer's initial business combination on a one-for-one basis, or at any time prior to the Issuer's initial business combination, at the option of the holder, subject to adjustment as more fully described under the heading "Description of Securities--Founder Shares" in the Issuer's registration statement on Form S-1 (File No. 333-297618). The 225,000 Class A Ordinary Shares are included in units (each unit consisting of one Class A Ordinary Share and one right to receive one-eighth (1/8) of a Class A Ordinary Share upon the consummation of an initial business combination), acquired pursuant to a Private Placement Units Purchase Agreement by and between PAC Sponsor, LLC (the "Sponsor") and the Issuer. Steven K. Hudson, Chairman and Chief Executive Officer of the Issuer, and AVR Capital Holdings, LLC, an affiliate of Andrew Rechtschaffen, a director of the Issuer, are the co-managing members of the Sponsor and control the management of the Sponsor, including the exercise of voting and investment discretion over the securities held by the Sponsor. Mr. Hudson disclaims any beneficial ownership of the reported shares other than to the extent of any pecuniary interest he may have therein, directly or indirectly. (2) Represents Class A Ordinary Shares that are included in the units (each unit consisting of one Class A Ordinary Share and a right to automatically receive one-eighth (1/8) of one Class A Ordinary Share upon consummation of the Issuer's initial business combination) (the "Public Units") purchased at the Issuer's initial public offering (the "IPO"). Class A Ordinary Shares, $0.0001 par value Pinnacle Acquisition Corporation 375 South County Road, Suite 220 Palm Beach FL 33480 Explanatory Note This Amendment No. 1 ("Amendment No. 1") amends and supplements the Schedule 13D filed with the Securities and Exchange Commission (the "SEC") on August 17, 2026 (the "Schedule 13D") relating to the Class A Ordinary Shares and Class A Ordinary Shares issuable upon conversion of Class B Ordinary Shares of the Issuer. Capitalized terms used herein without definition shall have the meaning set forth in the Schedule 13D. Item 4 of the Schedule 13D is hereby amended and supplemented by adding the following: On September 21, 2026, 750,000 Class B Ordinary Shares were surrendered for no consideration by the Sponsor and cancelled by the Issuer, pursuant to contractual arrangements under the Founder Share Purchase Agreement with the Issuer, because the underwriters did not exercise their over-allotment option. Item 5(a) - (c) of the Schedule 13D is hereby amended and restated in its entirety by inserting the following information: The aggregate number and percentage of Ordinary Shares beneficially owned by the Reporting Person (on the basis of a total of 25,225,000 Ordinary Shares, including 20,225,000 Class A Ordinary Shares and 5,000,000 Class B Ordinary Shares outstanding, as of September 21, 2026) are as follows: Amount beneficially owned: 6,475,000 Percentage: 25.67%. The aggregate number and percentage of Ordinary Shares beneficially owned by the Reporting Person (on the basis of a total of 25,225,000 Ordinary Shares, including 20,225,000 Class A Ordinary Shares and 5,000,000 Class B Ordinary Shares outstanding, as of September 21, 2026) are as follows: Number of shares to which the Reporting Person has: i. Sole power to vote or to direct the vote: 1,250,000 ii. Shared power to vote or to direct the vote: 5,225,000 iii. Sole power to dispose or to direct the disposition of: 1,250,000 iv. Shared power to dispose or to direct the disposition of: 5,225,000 The Reporting Person is a co-managing member of the Sponsor and shares the control and management of the Sponsor, including the exercise of voting and investment discretion over the securities held by the Sponsor. The Reporting Person disclaims any beneficial ownership of the reported shares other than to the extent of any pecuniary interest he may have therein, directly or indirectly. The Reporting Person has not effected any transactions of the Issuer's Ordinary Shares during the 60 days preceding the date of this report, except as described in Items 4 and 6 of this Amendment No.1 which information is incorporated herein by reference. Item 6 of the Schedule 13D is hereby amended and supplemented to include the following: The responses to Items 4 and 5 of this Amendment No. 1 are incorporated by reference into this Item 6. Steven Kenneth Hudson /s/ Steven K. Hudson 09/23/2026