X0303 4 2011-04-27 0 0001171500 PLATINUM UNDERWRITERS HOLDINGS LTD PTP 0001014160 CARMICHAEL DAN R C/O PLATINUM UNDERWRITERS HOLDINGS, LTD. 69 PITTS BAY ROAD, 3RD FLOOR PEMBROKE D0 HM 08 BERMUDA 1 0 0 0 Common Shares 2011-04-27 4 M 0 1362 0.00 A 58085 D Share units 2011-04-27 4 M 0 1362 0.00 D Common Shares 1362 0 D Share units 2011-04-27 4 A 0 1341 0.00 A Common Shares 1341 1341 D 1-for-1 These share units were awarded on April 29, 2010 pursuant to the Company's 2010 Share Incentive Plan. On the date of the Company's 2011 Annual General Meeting of Shareholders, the Company issued to the reporting person one Common Share of the Company for each of the share units awarded to the reporting person. These shares were awarded on April 27, 2011 pursuant to the Company's 2010 Share Incentive Plan. On the earlier to occur of the first anniversary of the date of the grant or the date of the Company's next Annual General Meeting of Shareholders, the Company will issue to the reporting person one Common Share of the Company for each of the share units awarded to the reporting person, subject to the reporting person's continued service with the Company through the applicable vesting date. Christina M. Parker, Attorney-in-fact 2011-04-27