Mitsui Sumitomo Insurance Co., Ltd.

Activist investor & 5%+ owner · SC 13D/13G filings

Total Filings

Stocks Covered

Latest Filing

Mar 5, 2026

Filings

W. R. BERKLEY CORPORATION

SC 13D/A · Mar 5, 2026

15.7%

58.8M shares

W. R. Berkley Corporation

SC 13D/A · Feb 7, 2026

14.9%

56.5M shares

W. R. BERKLEY CORPORATION

SC 13D/A · Jan 15, 2026

13.9%

52.7M shares

W. R. BERKLEY CORPORATION

SC 13D · Dec 11, 2025

12.8%

48.6M shares