A.M. Best Co. has affirmed the financial strength rating of A+ (Superior) of Jupiter Insurance Ltd of Guernsey. The rating outlook remains stable.

The rating reflects the company's superior risk-adjusted capitalisation and operating performance.

A partially offsetting factor is the company's high dependence on one large contract. Jupiter is a single parent captive of BP plc, which is an integrated oil and gas company.

Best said it believes that Jupiter's prospective risk-adjusted capitalisation is likely to remain superior. At year-end 2004, an anticipated 50% increase in retained earnings is likely to further strengthen capitalisation.

In addition, the company's practice of not using reinsurance leads to a low level of credit risk exposure.

The concentration risk, arising from the fact that most of investments are placed within the group, has been factored into the rating.