Mitsui Sumitomo Insurance and Aioi Nissay Dowa are set to merge in April 2027, a move aimed at creating Japan's largest nonlife insurer. The consolidation is intended to improve operational efficiency amid a shrinking domestic market, but it also raises concerns about increasing market concentration and potential risks of oligarchic influence.

An analyst noted that Mitsui Sumitomo Insurance Group's plan to acquire a 15% stake in WR Berkley may not lead to a takeover soon, positioning the move as a strategic long-term financial maneuver amid a high price-to-book trading environment.

Mitsui Sumitomo Insurance Co., along with other major insurers, was fined by Japan’s Fair Trade Commission for committing nine antitrust violations by colluding to adjust insurance fees in advance. The fine, part of a broader crackdown on non-competitive practices, highlights unethical business conduct that undermines consumer welfare and market fairness.

Mitsui Sumitomo Insurance Group, along with three other major non-life insurers, was ordered by Japan’s Finance Minister to end anti‐competitive practices aimed at artificially inflating premiums. The order requires the company to review and revamp its management controls to restore trust and comply with antitrust laws.

Japan's financial watchdog ordered Mitsui Sumitomo Insurance Group, along with three other major insurers, to reform its operations following findings of collusive behavior that inflated insurance premiums. The regulator demanded accountability from management and drastic operational reforms to safeguard market integrity.

On December 19, 2023, the Japan Fair Trade Commission raided four major insurers, including Mitsui Sumitomo Insurance Group, as part of an investigation into alleged cartel activities involving premium fixing and unreasonable trade constraints that violate antimonopoly laws.

Mitsui released its Anti-Slavery & Human Trafficking Statement for the fiscal year ended March 2023, detailing comprehensive measures including supplier questionnaire surveys, face-to-face inspections, corrective actions for non-compliant suppliers, and extensive employee training initiatives to ensure compliance with human rights standards.

The article details a significant update to supply chain management practices, where a human rights clause was added to standard purchase contracts in May 2023 and due diligence efforts have been expanded into high-risk sectors. This proactive initiative is designed to ensure suppliers adhere to sustainable and ethical standards, including the mitigation of forced labor and child labor risks.