International Marine Underwriters (IMU) offers a full range of ocean and inland marine insurance products.

A.W.G. Dewar's tuition refund plan protects schools and parents from the financial consequences of a student's withdrawal or dismissal from school.

OneBeacon Accident and Health focuses on analyzing and developing unique accident solutions and programs for the transportation, youth sports and corporate accident marketplace. We also provide medical excess coverages including medical stop loss for self-funded employers, as well as provider excess of loss insurance and HMO reinsurance for managed care organizations.

OneBeacon Financial Services offers property and casualty coverages for commercial banks, savings banks and savings and loan institutions, security broker-dealers, investment advisors, insurance companies and credit unions.

OneBeacon Management Liability offers D&O, EPL, fiduciary liability and crime insurance for nonprofits and private for-profit companies.


OneBeacon Environmental specializes in environmental risk solutions designed to address a variety of exposures for a broad range of businesses, including multiline casualty placements for the environmental industry.

OneBeacon Architects and Engineers offers professional liability coverage solutions targeted for this customer segment.

OneBeacon Technology Insurance solely focuses on the technology industry, making it a source for technology insurance and risk management needs.

OneBeacon Entertainment provides specialized commercial insurance products, including professional liability coverages, for the entertainment, sports and leisure industries.

OneBeacon Surety Group offers a broad range of commercial, custom and miscellaneous bonds targeting middle-market, Fortune 2500 companies.

OneBeacon Specialty Property provides excess property and inland marine solutions that augment primary policies or self-insured retentions.

OneBeacon Program Group provides a full range of multi-line package insurance solutions for select specialty programs overseen by dedicated MGAs, MGUs and Program Administrators.

OneBeacon Healthcare Group provides professional liability coverages and other specialized coverages for hospitals, physicians and complex risks; free-standing medical facilities; senior living organizations; and managed care organizations.

OneBeacon Government Risks provides solutions for midsized municipalities and counties, special districts and other publicly funded agencies.

OneBeacon Financial Institutions specializes in professional liability, management liability and fidelity coverages for a broad range of financial institutions.