Sompo Japan Insurance Under Review with Positive Implications for Credit Ratings

AM Best has placed the credit ratings of Sompo Japan Insurance Inc. and its subsidiaries under review with positive implications, following the announcement of its acquisition of Aspen Insurance Holdings Limited for approximately $3.5 billion. The transaction is expected to close in the first half of 2026 and could accelerate geographic diversification and enhance the group's presence in the global property/casualty market. The ratings will remain under review pending the completion of the transaction.

AM Best, a leading global credit rating agency, has placed the financial strength rating (FSR) and long-term issuer credit ratings (Long-Term ICR) of Sompo Japan Insurance Inc. and its subsidiaries under review with positive implications. The move follows the company's announcement of a definitive merger agreement to acquire Aspen Insurance Holdings Limited (Aspen) for approximately USD 3.5 billion in an all-cash transaction. The acquisition is expected to close in the first half of 2026, subject to regulatory approvals.

The FSR of A+ (Superior) and the Long-Term ICR of "aa-" (Superior) for Sompo Japan Insurance Inc. and its subsidiaries, including Endurance Assurance Corporation, Endurance Specialty Insurance Limited, and Sompo America Insurance Company, have been placed under review. Additionally, the Long-Term ICR of "a-" (Excellent) for Sompo International Holdings Ltd. (SIH), the intermediate holding company, and the Long-Term Issue Credit Rating of "a-" (Excellent) on $335 million 7% senior unsecured notes due by 2034, guaranteed by SIH, are also under review.

The under review status reflects the potential material benefits in Sompo's business profile following the acquisition of Aspen, which could accelerate geographic diversification and lead to a significant enhancement in its presence in the global property/casualty (re)insurance market. Aspen is a global (re)insurance player with a diversified underwriting portfolio and expertise in specialty lines.

Upon completion of the transaction, Aspen will become a subsidiary of SIH, the intermediate holding company under Sompo Japan Insurance Inc. The ratings will remain under review with positive implications pending the completion of the transaction and until AM Best can evaluate fully the impact on Sompo Japan Insurance Inc.'s rating fundamentals.

The transaction is expected to close in the first half of 2026, subject to regulatory approvals. Ratings are communicated to rated entities prior to publication, and unless stated otherwise, the ratings were not amended subsequent to that communication.

For more information, visit AM Best's website at [AM Best](https://www.ambest.com).

References:

[1] https://finance.yahoo.com/news/am-best-places-credit-ratings-165100122.html