Item 1.01. Entry into a Material Definitive Agreement. The Business Combination Agreement

Item 7.01 Regulation FD Disclosure. The Company and CAC have prepared a presentation that will be used by the parties in making presentations with respect to, among other things, the Business Combination. Attached hereto as Exhibit 99.1 and incorporated into this Item 7.01 by reference is a copy of the presentation. The information in this Item 7.01, including Exhibit 99.1, shall not be deemed “filed” for any purpose, including for the purposes of Section 18 of the Exchange Act or otherwise subject to the liabilities of that Section. The information in this Item 7.01, including Exhibit 99.1, shall not be deemed incorporated by reference into any filing under the Securities Act or the Exchange Act regardless of any general incorporation language in the filing. Forward-Looking Statements This Current Report on Form 8-K contains certain statements that are not historical facts and are forward-looking statements within the meaning of the federal securities laws with respect to the proposed business combination among CAC, Pubco, Merger Sub, the Company and the Seller (the “ Business Combination”), including without limitation statements regarding the anticipated benefits of the proposed Business Combination, the anticipated timing of the proposed Business Combination, the implied enterprise value, future financial condition and performance of the combined company after the Closing and expected financial impacts of the proposed Business Combination, the satisfaction of closing conditions to the proposed Business Combination, the level of redemptions of CAC’s public shareholders and the products and markets and expected future performance and market opportunities of the combined company. These forward-looking statements generally are identified by the words “believe,” “project,” “expect,” “anticipate,” “estimate,” “intend,” “think,” “strategy,” “future,” “opportunity,” “potential,” “plan,” “seeks,” “may,” “should,” “will,” “would,” “will be,” “will continue,” “will likely result,” and similar expressions, but the absence of these words does not mean that a statement is not forward-looking. Forward-looking statements are predictions, projections and other statements about future events that are based on current expectations and assumptions and, as a result, are subject to risks and uncertainties. These forward-looking statements are provided for illustrative purposes only and are not intended to serve as, and must not be relied on as, a guarantee, an assurance, a prediction or a definitive statement of fact or probability. Actual events and circumstances are difficult or impossible to predict and will differ from assumptions. Many factors could cause actual future events to differ materially from the forward-looking statements in this communication, including but not limited to: (i) the risk that the proposed Business Combination may not be completed in a timely manner or at all, which may adversely affect the price of CAC’s securities; (ii) the risk that the proposed Business Combination may not be completed by CAC’s business combination deadline; (iii) the failure to satisfy the conditions to the consummation of the proposed Business Combination, including the approval of the BCA by the shareholders of CAC, the satisfaction of the closing requirements and the receipt of certain governmental, regulatory and third party approvals; (iv) the occurrence of any event, change or other circumstance that could give rise to the termination of the BCA; (v) redemptions exceeding anticipated levels; (vi) the failure to meet Nasdaq initial listing standards in connection with the consummation of the proposed Business Combination; (vii) the effect of the announcement or pendency of the proposed Business Combination on the Company’s business relationships, operating results, and business generally; (viii) risks that the proposed Business Combination disrupts current plans and operations of the Company and the Seller; (ix) the outcome of any legal proceedings that may be instituted against CAC, Pubco, the Company or the Seller related to the BCA or the proposed Business Combination; (x) changes in the markets in which the Company competes, including with respect to its competitive landscape, technology evolution, or regulatory changes; (xi) changes in domestic and global general economic conditions; (xii) the risk that Pubco and the Company may not be able to execute its growth strategies; (xiii) risks related to supply chain disruptions; (xiv) the risk that Pubco may not be able to develop and maintain effective internal controls; (xv) costs related to the proposed Business Combination and the failure to realize anticipated benefits of the proposed Business Combination or to realize estimated pro forma results and underlying assumptions, including with respect to estimated shareholders redemptions; (xvi) the ability to recognize the anticipated benefits of the proposed Business Combination and to achieve commercialization and development plans, and identify and realize additional opportunities, which may be affected by, among other things, competition, the ability of the Company to grow and manage growth economically and hire and retain key employees; (xvii) inability to achieve successful results or to obtain licensing of third-party intellectual property rights for future discovery and development of the Company’s projects; (xviii) failure to commercialize products and achieve market acceptance of such products; (xix) the risk that the Company will need to raise additional capital to execute its business plan, which may not be available on acceptable terms or at all; (xx) the risk that Pubco, post-combination, experiences difficulties in managing its growth and expanding operations; (xxi) the risk of product liability or regulatory lawsuits or proceedings relating to the Company’s business; (xxii) risks associated with intellectual property protection; (xxiii) the risk that the Company is unable to secure or protect its intellectual property; and (xxiv) those factors discussed in CAC’s and Pubco’s filings with the SEC and that will be contained in the Registration Statement relating to the proposed Business Combination. The foregoing list of factors is not exhaustive. You should carefully consider the foregoing factors and the other risks and uncertainties that will be described in the “ Risk Factors” section of the Registration Statement on Form F-4 (the “ Registration Statement”) and the amendments thereto, and other documents to be filed by CAC and Pubco from time to time with the SEC. These filings identify and address other important risks and uncertainties that could cause actual events and results to differ materially from those contained in the forward-looking statements. Forward-looking statements speak only as of the date they are made. Readers are cautioned not to put undue reliance on forward-looking statements, and while the Pubco and CAC may elect to update these forward-looking statements at some point in the future, they assume no obligation to update or revise these forward-looking statements, whether as a result of new information, future events or otherwise, except as required by applicable law. None of Pubco, the Seller, the Company or CAC gives any assurance that Pubco, the Seller, the Company or CAC will achieve expectations. These forward-looking statements should not be relied upon as representing Pubco’s, CAC’s, the Seller’s or the Company’s assessments as of any date subsequent to the date of this Current Report. Accordingly, undue reliance should not be placed upon the forward-looking statements. Additional Information About the Proposed Business Combination and Where to Find It In connection witht he BCA and the Business Combination, Pubco intends to file relevant materials with the SEC, including the Registration Statement, which will include a proxy statement of CAC and a prospectus for the registration of Pubco securities in connection with the Business Combination. THE PARTIES URGE THEIR INVESTORS, SHAREHOLDERS, AND OTHER INTERESTED PERSONS TO READ, WHEN AVAILABLE, THE PRELIMINARY PROXY STATEMENT/PROSPECTUS AND DEFINITIVE PROXY STATEMENT/PROSPECTUS, IN EACH CASE WHEN FILED WITH THE SEC AND DOCUMENTS INCORPORATED BY REFERENCE THEREIN BECAUSE THESE DOCUMENTS WILL CONTAIN IMPORTANT INFORMATION ABOUT CAC, PUBCO, THE SELLER AND THE PROPOSED BUSINESS COMBINATION. After the registration statement is declared effective by the SEC, the definitive proxy statement/prospectus and other relevant documents will be mailed to the shareholders of CAC as of the record date in the future to be established for voting on the Business Combination and will contain important information about the Business Combination and related matters. Shareholders of CAC and other interested persons are advised to read, when available, these materials (including any amendments or supplements thereto) and any other relevant documents in connection with CAC’s solicitation of proxies for the meeting of shareholders to be held to approve, among other things, the Business Combination, because they will contain important information about CAC, Pubco, the Seller and the Business Combination. Shareholders and other interested persons will also be able to obtain copies of the preliminary proxy statement/prospectus, the definitive proxy statement/prospectus, and other relevant materials in connection with the Business Combination, without charge, once available, at the SEC’s website at www. sec. gov or by directing a request to: Columbus Acquisition Corp, 14 Prudential Tower, Singapore 049712, telephone: +1 949 899 1827. The information contained on, or that may be accessed through, the websites referenced in this Form 8-K in each case is not incorporated by reference into, and is not a part of, this Form 8-K. Participants in the Solicitation CAC, Pubco, the Seller, and their respective directors, executive officers, other members of management, and employees, under SEC rules, may be deemed participants in the solicitation of proxies of CAC’s shareholders in connection with the Business Combination. Investors and security holders may obtain more detailed information regarding the names and interests in the Business Combination of the directors and officers of CAC, Pubco and the Seller in the registration statement on Form F-4 to be filed with the SEC by Pubco, which will include the proxy statement of CAC for the Business Combination. Information about CAC’s directors and executive officers is also available in CAC’s filings with the SEC. Non-Solicitation This Current Report on Form 8-K is not a proxy statement or solicitation of a proxy, consent or authorization with respect to any securities or in respect of the Business Combination and shall not constitute an offer to sell or a solicitation of an offer to buy any securities, or a solicitation of any vote or approval, nor shall there be any sale of securities in any state or jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of the Securities Act of 1933, as amended, or an exemption therefrom.

Item 9.01 Exhibits. (d) Exhibits The following exhibits are being filed herewith: Exhibit No. Description 2.1* Business Combination Agreement, dated as of November 9, 2025, by and among Columbus Acquisition Corp, WISeSat. Space Holdings Corp., WISeSat Merger Sub Corp., WISeSat. Space Corp., and WISeKey International Holding Ltd. 10.1 Sponsor Agreement, dated as of November 9, 2025, by and among Hercules Capital Management VII Corp, WISeSat. Space Corp., WISeSat. Space Holdings Corp., and Columbus Acquisition Corp. 10.2 Insider Letter Amendment, dated as of November 9, 2025, by and among Columbus Acquisition Corp, WISeSat. Space Holdings Corp., Hercules Capital Management VII Corp, WISeSat. Space Corp., and the undersigned individuals therein. 10.3 Lock-up Agreement, dated as of November 9, 2025, by and among WISeSat. Space Holdings Corp., Columbus Acquisition Corp, and the undersigned therein. ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── 10.4 Form 99.1 Presentation 104 Cover Page Interactive Data File (embedded within the Inline XBRL document) Certain exhibits and schedules to this Exhibit have been omitted in accordance with Regulation S-K Item 601(b)(2). SPAC agrees to furnish supplementally a copy of all omitted exhibits and schedules to the SEC upon its request. SIGNATURES 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. Dated: November 13, 2025 ────────────────────────────────────────────────────────── COLUMBUS ACQUISITION CORP By: /s/ Fen Zhang Name: Fen Zhang Title: Chief Executive Officer