---
schema_version: "secwatch.filing_event.v1"
accession: "0000947484-24-000063"
form_type: "8-K"
ticker: "ACGL"
cik: "0000947484"
company_name: "ARCH CAPITAL GROUP LTD."
filed_at: "2024-05-01T23:59:59+00:00"
generated_at: "2026-06-03T03:50:18.758001+00:00"
event_type: "m_and_a"
sentiment: "neutral"
materiality_score: 0.3
calibrated_materiality_score: 0.3
confidence: "medium"
source: SEC EDGAR
---

# Arch Capital completes sale of Castel Underwriting to Ryan Specialty

## Summary
- Castel Underwriting Agencies Limited sold to a Ryan Specialty subsidiary on May 1, 2024.
- Castel is a London-based managing general underwriting platform.
- Financial terms of the transaction were not disclosed in the filing.

## SEC filing metadata
- accession: 0000947484-24-000063
- form_type: 8-K
- ticker: ACGL
- cik: 0000947484
- company_name: ARCH CAPITAL GROUP LTD.
- filed_at: 2024-05-01T23:59:59+00:00
- event_type: m_and_a
- sentiment: neutral
- materiality_score: 0.3
- calibrated_materiality_score: 0.3
- confidence: medium
- sec_items: 7.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/947484/000094748424000063/0000947484-24-000063-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/947484/000094748424000063/acgl-20240501.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000947484-24-000063
- JSON: https://secwatch.observer/filing/0000947484-24-000063.json
- Plain text: https://secwatch.observer/filing/0000947484-24-000063.txt

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