Our ratings on Mitsui Sumitomo Insurance Co. Ltd. (MSI; A+/Stable/A-1) reflect its position as a core operating entity of MS&AD Insurance Group, a very strong market position in both commercial and individual insurance, and an expanding overseas business, especially in Asia. At the same time, the ratings are constrained by the vulnerability of its capital to stock price fluctuations, weaker profitability than international peers, and continued difficulties in the domestic business environment, such as limited growth potential and intense competition. Based on Standard&Poor's Ratings Services' group rating methodology, MSI is classified as a core entity within MS&AD Insurance Group. This is due to the insurer's status as the group's largest operating subsidiary that engages in domestic non-life insurance
