X0202 4 2008-02-20 0 0001171500 PLATINUM UNDERWRITERS HOLDINGS LTD PTP 0001354076 Porter Robert S THE BELVEDERE BUILDING 69 PITTS BAY ROAD, 2ND FLOOR PEMBROKE D0 HM 08 BERMUDA 0 1 0 0 CEO - Platinum Bermuda Share units 2008-02-20 4 A 0 6265 A Common Shares 6265 6265 D Non-qualified Option (Right to Buy) 33.92 2008-02-20 4 A 0 29150 A 2018-02-20 Common Shares 29150 29150 D Share units 2008-02-20 4 A 0 12530 A Common Shares 12530 12530 D 1-for-1 These share units were awarded under the 2006 Share Incentive Plan (the "SIP") of Platinum Underwriters Holdings, Ltd. (the "Company"). Pursuant to the Company's Policy for Awards under the SIP, the date of grant of this award is February 21, 2008. 50% of these share units will vest on February each of the third and fourth anniversaries of the date of grant. On each of these vesting dates, the Company will issue to the reporting person one Common Share of the Company for each vested share unit, reduced by the number of Common Shares which are equal in Fair Market Value (as defined in the SIP) on such date to the reporting person's tax withholding obligation. Not applicable. The option, which was awarded under the SIP, vests in four equal installments on each of the first four anniversaries of the date of grant. Pursuant to the Company's Policy for Awards under the SIP, the date of grant of this award is February 21, 2008. These share units were awarded pursuant to the Company's Amended and Restated Annual Incentive Plan. Pursuant to the Company's Policy for Awards under the SIP, the date of grant of this award is February 21, 2008. The share units are fully vested and will be paid to the reporting person 30 days after the date of grant in the form of one Common Share of the Company for each share unit awarded to the reporting person, reduced by the number of Common Shares which are equal in Fair Market Value (as defined in the SIP) on such date to the reporting person's tax withholding obligation. Michael E. Lombardozzi 2008-02-22