---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-066218"
form_type: "8-K"
ticker: "WRB"
cik: "0000011544"
company_name: "BERKLEY W R CORP"
filed_at: "2025-03-28T23:59:59+00:00"
generated_at: "2026-05-24T02:55:04.861452+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Mitsui Sumitomo to buy 15% of W.R. Berkley shares; Berkley family keeps stake

## Summary
- MSI to purchase 15% of WRB common stock via open-market/private transactions from third parties only.
- Berkley family (owning ~16%) will not sell any shares; will retain two board seats.
- After MSI reaches 4.9% ownership, MSI agrees to vote with Berkley family recommendations.
- At 12.5%, Berkley family will nominate an MSI director designee for Board approval.
- Investment subject to regulatory approvals; expected to close by end of March 2026.

## SEC filing metadata
- accession: 0001193125-25-066218
- form_type: 8-K
- ticker: WRB
- cik: 0000011544
- company_name: BERKLEY W R CORP
- filed_at: 2025-03-28T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/11544/000119312525066218/0001193125-25-066218-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/11544/000119312525066218/d934374d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-066218
- JSON: https://secwatch.observer/filing/0001193125-25-066218.json
- Plain text: https://secwatch.observer/filing/0001193125-25-066218.txt

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