---
schema_version: "secwatch.filing_event.v1"
accession: "0001213900-26-066255"
form_type: "8-K"
ticker: "KEYY"
cik: "0002102771"
company_name: "Keystone Acquisition Corp."
filed_at: "2026-06-08T19:37:22+00:00"
generated_at: "2026-06-08T19:38:28.490175+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# Keystone Acquisition Corp. closes $287.5M SPAC IPO, appoints John Boehner to board

## Summary
- IPO of 28.75M units at $10.025/unit, including full over-allotment; gross proceeds $287.5M.
- Concurrent private placement of 8.47M warrants at $1.00/warrant to sponsor and underwriters; trust funded $288.2M.
- Target sectors: US industrial development (energy transition, critical minerals, shipbuilding, semiconductors, data centers, digital assets).
- Board adds former Speaker John Boehner, Paul Cho, Martin Payne as independent directors; Boehner chairs Compensation Committee.

## SEC filing metadata
- accession: 0001213900-26-066255
- form_type: 8-K
- ticker: KEYY
- cik: 0002102771
- company_name: Keystone Acquisition Corp.
- filed_at: 2026-06-08T19:37:22+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 1.01, 3.02, 5.02, 5.03, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/2102771/000121390026066255/0001213900-26-066255-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/2102771/000121390026066255/ea0293899-8k_keystone.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001213900-26-066255
- JSON: https://secwatch.observer/filing/0001213900-26-066255.json
- Plain text: https://secwatch.observer/filing/0001213900-26-066255.txt

## Key facts
- Equity Issuances
  Keystone Acquisition Corp. issued an aggregate of 8,468,750 warrants of warrant to the Sponsor and the Representatives for $1.00 per Private Placement Warrant.
  - Security: warrant
  - Shares: an aggregate of 8,468,750 warrants
  - Purchaser: the Sponsor and the Representatives
  - Consideration: $1.00 per Private Placement Warrant
  source text: On June 4, 2026, simultaneously with the closing of the IPO, pursuant to the Private Placement Warrants Purchase Agreements, the Company completed the private sale of an aggregate of 8,468,750 warrants (the “ Private Placement Warrants ”) to the Sponsor and the Representatives at a purchase price of $1.00 per Private Placement Warrant, generating gross proceeds to the Company of $8,468,750.
  evidence_url: https://www.sec.gov/Archives/edgar/data/2102771/000121390026066255/0001213900-26-066255-index.htm
- Executive change
  John A. Boehner was appointed as Director at Keystone Acquisition Corp..
  - Action: appointed
  - Role: Director
  source text: On June 2, 2026, in connection with the IPO, Speaker John A. Boehner, Paul Y. Cho and Martin Payne were appointed to the board of directors of the Company (the “ Board ”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/2102771/000121390026066255/0001213900-26-066255-index.htm
- Executive change
  Martin Payne was appointed as Director at Keystone Acquisition Corp..
  - Action: appointed
  - Role: Director
  source text: On June 2, 2026, in connection with the IPO, Speaker John A. Boehner, Paul Y. Cho and Martin Payne were appointed to the board of directors of the Company (the “ Board ”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/2102771/000121390026066255/0001213900-26-066255-index.htm
- Executive change
  Paul Y. Cho was appointed as Director at Keystone Acquisition Corp..
  - Action: appointed
  - Role: Director
  source text: On June 2, 2026, in connection with the IPO, Speaker John A. Boehner, Paul Y. Cho and Martin Payne were appointed to the board of directors of the Company (the “ Board ”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/2102771/000121390026066255/0001213900-26-066255-index.htm
- Governance Changes
  Keystone Acquisition Corp.: Adopted Amended and Restated Memorandum and Articles of Association in connection with IPO (effective 2026-06-02).
  - Change: charter amendment
  - Effective: 2026-06-02
  source text: On June 2, 2026, in connection with the IPO, the Company adopted its Amended and Restated Memorandum and Articles of Association (the “ Amended Articles ”), effective the same day.
  evidence_url: https://www.sec.gov/Archives/edgar/data/2102771/000121390026066255/0001213900-26-066255-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.