UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2025 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number: 001-42607 Dune Acquisition Corp. II (Exact name of registrant as specified in its charter) | Cayman Islands | N/A | | --- | --- | | (Sta ...

Financial Performance - For the three months ended September 30, 2025, the company reported a net income of $1,335,424, primarily from interest income on marketable securities of $1,514,706, offset by costs of $179,282 [121]. - The company generated non-operating income from interest on marketable securities, with net income for the nine months ended September 30, 2025, totaling $2,048,349 [121]. - The company incurred a net loss of $16,230 for the period from inception (September 13, 2024) through September 30, 2024, due to formation and administrative costs [122]. Initial Public Offering - The company completed its Initial Public Offering on May 8, 2025, raising gross proceeds of $143,750,000 from the sale of 14,375,000 Units at $10.00 per Unit [123]. - Total transaction costs incurred during the Initial Public Offering amounted to $6,637,469, which included a cash underwriting fee of $550,000 and deferred underwriting fees of $5,750,000 [124]. Financial Position - As of September 30, 2025, the company had marketable securities held in the Trust Account amounting to $146,497,545, including approximately $2,388,170 of interest income [127]. - As of September 30, 2025, the company had cash of $401,902 and a working capital surplus of $401,633, intended for identifying and evaluating target businesses [132]. - The company has no off-balance sheet arrangements or long-term liabilities, except for an agreement with the Sponsor for $15,000 per month for administrative support [134]. Future Capital Needs - The company may need to raise additional capital through loans or investments to meet working capital needs, raising concerns about its ability to continue as a going concern [133]. - The company intends to use substantially all funds in the Trust Account to complete its Business Combination, with remaining proceeds for working capital and growth strategies [127].

Financial Performance - The company had a net income of $761,019 for the three months ended June 30, 2025, primarily from interest income of $873,464 on marketable securities held in the Trust Account[117]. - For the six months ended June 30, 2025, the company reported a net income of $712,925, with interest income of $973,464 offset by formation and administrative costs of $160,539[118]. Initial Public Offering (IPO) - The Initial Public Offering (IPO) generated gross proceeds of $143,750,000 from the sale of 14,375,000 Units, including an over-allotment option[119]. - Following the IPO, a total of $144,109,375 was placed in the Trust Account, with transaction costs amounting to $6,637,469[120]. Trust Account and Securities - As of June 30, 2025, the company held marketable securities in the Trust Account valued at $144,982,390, including approximately $873,464 of interest income[122]. Cash and Financing - The company had cash of $589,755 as of June 30, 2025, intended for identifying and evaluating target businesses[123]. - The company does not have any long-term debt or off-balance sheet arrangements as of June 30, 2025[126]. - The company does not anticipate needing to raise additional funds for operating expenses but may require financing for a Business Combination if significant redemptions occur[125]. Business Combination - The company may seek to extend the Combination Period, which requires public shareholder approval and may affect its Nasdaq listing[115]. - The company incurred monthly fees of $15,000 for administrative support starting May 6, 2025, until the completion of the Business Combination[127].

As filed with the U.S. Securities and Exchange Commission on April 29, 2025. Registration No. 333-285639 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ____________________ AMENDMENT NO. 2 TO FORM S-1 REGISTRATION STATEMENT Cayman Islands 6770 N/A (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) (I.R.S. Employer Identification Number) 700 S. Rosemary Avenue, Suite 204 West Palm Beach, FL 33401 Telephone: (917) 74 ...

As filed with the U.S. Securities and Exchange Commission on March 25, 2025. Registration No. 333-285639 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 ____________________ DUNE ACQUISITION CORPORATION II (Exact name of registrant as specified in its charter) ____________________ Cayman Islands 6770 N/A (State or other jurisdiction of incorporation or organization) (Primary Stand ...

As filed with the U.S. Securities and Exchange Commission on March 7, 2025. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ____________________ FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 ____________________ DUNE ACQUISITION CORPORATION II (Exact name of registrant as specified in its charter) ____________________ Cayman Islands 6770 N/A (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classificat ...