Japanese Major Insurer Makes Bold $40 Million Purchase of U.S. Insurance Stocks

Between February 17 and 18, Japan’s Mitsui Sumitomo Insurance, under a predetermined trading plan, net purchased approximately 560,000 shares of W. R. Berkley Corporation common stock on the open market. The total purchase cost was about $40 million (roughly KRW 58 billion), raising Mitsui Sumitomo’s direct stake to around 57 million shares. In its disclosure, parent company MS&AD Insurance Group denied any beneficial ownership beyond the economic interest threshold and rejected any status as a concert party with existing counterparties.

In its late-January announcement of fourth-quarter and full-year 2025 results, W. R. Berkley reported record-high underwriting profit, net income and investment income, delivering a double-digit return on equity. The stock closed at $69.70 on February 13—more than 10% below its 52-week high—and some long-term investors have slightly trimmed their holdings since the third quarter of 2025.

Headquartered in Greenwich, Connecticut, W. R. Berkley is a commercial property and casualty (P&C) insurance and reinsurance holding company with strengths in specialty lines and small-to-medium-enterprise commercial insurance. Mitsui Sumitomo Insurance and MS&AD Insurance Group are leading Asian P&C insurers that have expanded their global portfolios through equity stakes in and partnerships with North American and European insurers.