---
schema_version: "secwatch.filing_event.v1"
accession: "0001213900-26-067269"
form_type: "8-K"
ticker: "KEYY"
cik: "0002102771"
company_name: "Keystone Acquisition Corp."
filed_at: "2026-06-10T19:08:07+00:00"
generated_at: "2026-06-10T19:09:13.171396+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Keystone Acquisition Corp. closes $287.5M IPO and $8.5M private placement

## Summary
- IPO of 28,750,000 units at $10.00/unit raised $287.5M gross.
- Private placement of 8,468,750 warrants at $1.00 each raised $8.47M.
- $288.2M placed in trust account at $10.025 per unit.
- Transaction costs totaled $17.87M including $11.5M deferred underwriting.
- As of June 4, 2026, working capital outside trust was $1.26M.

## SEC filing metadata
- accession: 0001213900-26-067269
- form_type: 8-K
- ticker: KEYY
- cik: 0002102771
- company_name: Keystone Acquisition Corp.
- filed_at: 2026-06-10T19:08:07+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/2102771/000121390026067269/0001213900-26-067269-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/2102771/000121390026067269/ea0294122-8k_keystone.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001213900-26-067269
- JSON: https://secwatch.observer/filing/0001213900-26-067269.json
- Plain text: https://secwatch.observer/filing/0001213900-26-067269.txt

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