{"url_path":"/sec/keyy/8-k/2026-06-08/cover-page","section_key":"cover-page","section_title":"Cover Page","topic":"sec","document":{"doc_type":"8-K","doc_date":"2026-06-08","source_url":"https://www.sec.gov/Archives/edgar/data/2102771/0001213900-26-066255-index.html","accession_number":"0001213900-26-066255","cik":"0002102771","ticker":"KEYY","issuer_name":"Keystone Acquisition Corp.","edgar_url":"https://www.sec.gov/Archives/edgar/data/2102771/0001213900-26-066255-index.html","primary_entity_key":"0002102771","primary_entity_name":"Keystone Acquisition Corp."},"word_count":383,"has_tables":true,"body_markdown":"false\n--12-31\n0002102771\n00-0000000\n\n0002102771\n\n2026-06-02\n2026-06-02\n\n0002102771\n\nKEYYU:UnitsEachConsistingOfOneClassOrdinaryShare0.0001ParValueAndOnehalfOfOneRedeemableWarrantMember\n\n2026-06-02\n2026-06-02\n\n0002102771\n\nKEYYU:ClassOrdinarySharesParValue0.0001PerShareMember\n\n2026-06-02\n2026-06-02\n\n0002102771\n\nKEYYU:WarrantsEachWholeWarrantExercisableForOneClassOrdinaryShareAtExercisePriceOf11.50PerShareMember\n\n2026-06-02\n2026-06-02\n\niso4217:USD\n\nxbrli:shares\n\niso4217:USD\n\nxbrli:shares\n\n \n\n \n\n**UNITED STATES\nSECURITIES AND EXCHANGE COMMISSION\nWashington, D.C. 20549**\n\n \n\n**FORM 8-K**\n\n \n\n**CURRENT REPORT**\n\n \n\n**PURSUANT TO SECTION 13 OR 15(d) OF THE\nSECURITIES EXCHANGE ACT OF 1934**\n\n** **\n\nDate of Report (Date of earliest event reported):\n**June 2, 2026**\n\n** **\n\n**KEYSTONE ACQUISITION CORP. **\n\n(Exact name of registrant as specified in its charter)\n\n \n\n**Cayman Islands**\n \n**001-43320**\n \n**N/A**\n\n(State or other jurisdiction\n\nof incorporation)\n \n(Commission File Number)\n \n(IRS Employer\n\nIdentification No.)\n\n** **\n\n**142 West 57th Street**\n\n**11th Floor**\n\n**New York, New York 10019**\n\n(Address of principal executive offices, including\nzip code)\n\n \n\nRegistrant’s telephone number, including\narea code: **(408) 482-7532**\n\n \n\n**Not Applicable**\n\n****(Former name or former address, if changed since last report)\n\n \n\nSecurities registered pursuant to Section 12(b)\nof the Act:\n\n \n\nTitle of each class\n \nTrading Symbol(s)\n \nName of each exchange on which registered\n\n**Units, each consisting of one Class A ordinary share, $0.0001 par value, and one-half of one redeemable warrant**\n \n**KEYYU**\n \n**The Nasdaq Stock Market LLC**\n\n**Class A ordinary shares, par value $0.0001 per share**\n \n**KEYY**\n \n**The Nasdaq Stock Market LLC**\n\n**Warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 per share**\n \n**KEYYW**\n \n**The Nasdaq Stock Market LLC**\n\n \n\nCheck the appropriate box below if the Form 8-K\nfiling is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:\n\n \n\n☐\nWritten communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)\n\n \n \n\n☐\nSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)\n\n \n \n\n☐\nPre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))\n\n \n \n\n☐\nPre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))\n\n** **\n\nIndicate by check mark whether the registrant\nis an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the\nSecurities Exchange Act of 1934 (§240.12b-2 of this chapter).\n\n \n\nEmerging growth company ☒\n\n \n\nIf an emerging growth company, indicate by check\nmark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting\nstandards provided pursuant to Section 13(a) of the Exchange Act. ☐"}