Mitsui Sumitomo Insurance Co Ltd

In its 13F for Q1 2026 (holdings as of March 31, 2026, filed May 14, 2026), Mitsui Sumitomo Insurance Co Ltd reported 1 stock position worth $3.9 billion. Its top holding was WR Berkley (WRB) at 100.0% of the portfolio. Compared with Q4 2025, it added to 1. The biggest buy was WR Berkley (WRB, shares +16%).

Most Recent 13F
Q2 2026
Location
Tokyo, M0
CIK
0001142206
Portfolio Value
$3.9B (Q1 2026)
SEC Filing
0001193125-26-222668 ↗ filed May 14, 2026

Holdings Value

0$1.0B$2.0B$3.0B$4.0B$5.0B Q4 2025: $3.5B Q4 2025 Q1 2026: $3.9B $3.9B Q1 2026 Q2 2026: $4.1B Q2 2026

Holdings 1 stocks · $3.9B
WRB WR Berkley Corp. filed as BERKLEY W R CORP 100.00% 58,780,450 $3.9B Add +16.3%

Portfolio Sells Q4 2025 → Q1 2026
None this quarter.

Portfolio Buys Q4 2025 → Q1 2026
WRB WR Berkley Corp. Add +16.3% 100.00% 0.00

All Filings

QuarterPositions13F Reported ValueTop Holdings
Q2 2026 1$4.1BWRB
Q1 2026 1$3.9BWRB
Q4 2025 1$3.5BWRB