A.M. Best has affirmed the financial strength rating of A (Excellent) and issuer credit ratings (ICR) of “a” of Platinum Underwriters Bermuda, Ltd. (Platinum) (Bermuda) and its strategic affiliate, Platinum Underwriters Reinsurance, Inc. (Baltimore, MD). A.M. Best also has affirmed the ICR of “bbb” of Platinum’s holding company, Platinum Underwriters Holdings, Ltd. (Platinum Holdings) (Bermuda) [NYSE:PTP], and the debt ratings of Platinum Holdings and Platinum Underwriters Finance, Inc . (Delaware). The outlook for all ratings is stable. (See below for a detailed list of the debt ratings.) The ratings reflect Platinum’s excellent risk-adjusted capitalization, stable management team, profitability-focused business strategy (which places a strong emphasis on cycle management) and solid enterprise risk management capabilities. The ratings also consider the organization’s market profile and low financial leverage. Platinum continues to execute its cycle management strategy on its streamlined and efficient operating platform, which has benefited the company through the generation of strong historical long-term returns, while maintaining excellent risk-adjusted capitalization. Although the market conditions are very competitive, the company remains focused on disciplined underwriting, risk management and profitability. Somewhat offsetting these strengths are A.M. Best’s concerns that Platinum’s resolute cycle management strategy may someday impede its ability to take optimum advantage of future market opportunities as they arise. While it may still be too early to fully evaluate the impact of such a strategy across the entire business cycle, A.M. Best will continue to monitor the organization’s business profile and market position. Factors that could lead to an upgrading of Platinum’s ratings include sustained, long-term favorable operating profitability, coupled with maintenance of strong risk-adjusted capital levels. Factors that could lead to a downgrading of Platinum’s ratings and/or a revision of the outlook to negative include unfavorable operating profitability trends, outsized catastrophe or investment losses relative to expectations and peers, significant adverse loss reserve development and/or a material decline in risk-adjusted capital.