Platinum Underwriters Holdings, Ltd. Comments on Loss Estimates for Second and First Quarter 2011 Catastrophes

Platinum Underwriters Holdings, Ltd. PTP today announced that it expects losses from catastrophes in the second quarter of 2011 and increases to its loss estimates for catastrophes in the first quarter of 2011 will have a net negative impact of approximately $74.8 million on the Company's second quarter 2011 results. The net negative impact from these events includes an estimate of losses and loss adjustment expenses, net of retrocessional coverage, reinstatement premiums, taxes and the expected impact of foreign exchange rates. Approximately $28.0 million of the estimated net negative impact relates to the severe weather in the Midwest and Southeast regions of the United States during April and May of 2011 and is based on the Company's portfolio modeling, discussions with brokers and clients, market share analysis and a review of the Company's in-force contracts. The balance of the estimated net negative impact relates to an increase of the Company's loss estimates for catastrophes in the first quarter of 2011 and is based primarily on information received from clients.