S-1Accepted May 4, 5:15 PM ET

Keystone Acquisition Corp. S-1

KEYYKeystone Acquisition Corp.

sec.gov View full filing

Accepted (ET)

5:15 PM

May 4, 2026

Filed

May 4, 2026

Documents

Size

10.6 MB

Summary

Summary not available

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Filing details

Company: Keystone Acquisition Corp.
Ticker: KEYY
CIK: 0002102771
Form: S-1
Accepted: May 4, 5:15 PM ET
Filed: May 4, 2026
Size: 10.6 MB
Accession: 0001213900-26-051706

Documents · 59

ea0272937-04.htmPrimary
REGISTRATION STATEMENT
ea027293704ex1-1_keystone.htm
FORM OF UNDERWRITING AGREEMENT
ea027293704ex3-1_keystone.htm
MEMORANDUM AND ARTICLES OF ASSOCIATION
ea027293704ex3-2_keystone.htm
FORM OF AMENDED AND RESTATED MEMORANDUM AND ARTICLES OF ASSOCIATION
ea027293704ex4-1_keystone.htm
SPECIMEN UNIT CERTIFICATE
ea027293704ex4-2_keystone.htm
SPECIMEN ORDINARY SHARE CERTIFICATE
ea027293704ex4-4_keystone.htm
FORM OF WARRANT AGREEMENT BETWEEN EFFICIENCY AND THE REGISTRANT
ea027293704ex5-1_keystone.htm
OPINION OF PILLSBURY WINTHROP SHAW PITTMAN LLP
ea027293704ex5-2_keystone.htm
OPINION OF MAPLES AND CALDER (CAYMAN) LLP, CAYMAN ISLANDS COUNSEL TO THE REGISTRANT
ea027293704ex10-1_keystone.htm
FORM OF LETTER AGREEMENT AMONG THE REGISTRANT, KEYSTONE INTERNATIONAL ACQUISITION MANAGEMENT LLC AND EACH OF THE OFFICERS AND DIRECTORS OF THE REGISTRANT
ea027293704ex10-2_keystone.htm
FORM OF INVESTMENT MANAGEMENT TRUST AGREEMENT BETWEEN EFFICIENCY AND THE REGISTRANT
ea027293704ex10-3_keystone.htm
FORM OF REGISTRATION RIGHTS AGREEMENT AMONG THE REGISTRANT, KEYSTONE INTERNATIONAL ACQUISITION MANAGEMENT LLC AND THE HOLDERS SIGNATORY THERETO
ea027293704ex10-4_keystone.htm
FORM OF PRIVATE PLACEMENT WARRANTS PURCHASE AGREEMENT BETWEEN THE REGISTRANT AND KEYSTONE INTERNATIONAL ACQUISITION MANAGEMENT LLC
ea027293704ex10-5_keystone.htm
FORM OF PRIVATE PLACEMENT WARRANTS PURCHASE AGREEMENT BETWEEN THE REGISTRANT AND THE UNDERWRITERS
ea027293704ex10-6_keystone.htm
FORM OF INDEMNITY AGREEMENT
ea027293704ex10-7_keystone.htm
PROMISSORY NOTE ISSUED TO KEYSTONE INTERNATIONAL ACQUISITION MANAGEMENT LLC
ea027293704ex10-8_keystone.htm
SECURITIES SUBSCRIPTION AGREEMENT BETWEEN KEYSTONE INTERNATIONAL ACQUISITION MANAGEMENT LLC AND THE REGISTRANT
ea027293704ex10-9_keystone.htm
FORM OF ADMINISTRATIVE SERVICES AND INDEMNIFICATION AGREEMENT
ea027293704ex14-1_keystone.htm
FORM OF CODE OF ETHICS
ea027293704ex23-1_keystone.htm
CONSENT OF WITHUMSMITH+BROWN, PC
ea027293704ex99-1_keystone.htm
AUDIT COMMITTEE CHARTER
ea027293704ex99-2_keystone.htm
COMPENSATION COMMITTEE CHARTER
ea027293704ex99-3_keystone.htm
CLAWBACK POLICY
ea027293704ex99-4_keystone.htm
CONSENT OF SPEAKER JOHN BOEHNER
ea027293704ex99-5_keystone.htm
CONSENT OF PAUL Y. CHO
ea027293704ex99-6_keystone.htm
CONSENT OF MARTIN PAYNE
ea027293704ex-fee_keystone.htm
FILING FEE TABLE
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