AM Best has upgraded its financial strength and issuer credit ratings on Ironshore and affiliated operating companies.

The move, from A- to A, reflects the Bermudan insurer’s “strong risk-adjusted capitalisation, enhanced business profile as a specialty casualty underwriter and highly experienced management team”.

Ironshore has developed a select portfolio of global specialty business and continues to attract highly qualified professionals, the ratings agency says.

“These strengths are partially offset by Ironshore’s limited operating history and significant growth in medium-tail casualty classes of business during a soft phase of the casualty market.”

The outlook for all ratings has been revised from positive to stable.