Platinum Underwriters (PTP) 8-K Platinum Underwriters Holdings, LTD. Reports Record

Exhibit 99.2

Financial Supplement

Financial Information

as of June 30, 2010

(UNAUDITED)

The following supplement of information is provided to assist in your understanding of

Platinum Underwriters Holdings, Ltd.

This report is for informational purposes only.  It should be read in conjunction with

documents filed with the Securities and Exchange Commission by Platinum Underwriters Holdings, Ltd.,

including the Company's Annual Report on Form 10-K and Quarterly Report on Form 10-Q.

Our Investor Relations Department can be reached at (441) 298-0760.

Platinum Underwriters Holdings, Ltd.
Overview
June 30, 2010
Address:	Investor Information:
Platinum Underwriters Holdings, Ltd.	Lily Outerbridge
The Belvedere Building	Vice President, Director of Investor Relations
69 Pitts Bay Road	Tel:  (441) 298-0760
Pembroke, HM 08  Bermuda	Fax:  (441) 296-0528
Website:  www.platinumre.com	Email: louterbridge@platinumre.com

Definitions and presentation:

All financial information contained herein is unaudited except for the information for the fiscal year ended December 31, 2009.   Certain amounts in prior periods have been reclassified to conform to current period presentation.  Amounts may not reconcile exactly due to rounding differences.

In presenting the Company's results, management has included certain schedules containing financial measures that are not calculated under standards or rules that comprise accounting principles generally accepted in the United States (GAAP). Such measures, including segment underwriting income or loss, operating income or loss, related underwriting ratios and fully converted book value per common share, are referred to as non-GAAP. These non-GAAP measures may be defined or calculated differently by other companies.  Management believes these measures, which are used to monitor the results of operations, allow for a more complete understanding of the underlying business.  These measures should not be viewed as a substitute for those determined in accordance with GAAP.  Reconciliations of such measures to the m ost comparable GAAP figures are included within this financial supplement in accordance with Regulation G.

Safe Harbor Statement Regarding Forward-Looking Statements:

This financial supplement contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934 (the “Exchange Act”).  Forward-looking statements are based on our current plans or expectations that are inherently subject to significant business, economic and competitive uncertainties and contingencies.  These uncertainties and contingencies can affect actual results and could cause actual results to differ materially from those expressed in any forward-looking statements made by, or on behalf of, us.  In particular, statements using words such as “may,” “should,” “estimate,” “expect,” “anticipate,” “intend,” “believe,” “predict,” “potential,” or words of similar import generally involve forward-looking statements.  The inclusion of forward-looking statements in this financial supplement should not be considered as a representation by us or any other person that our current plans or expectations will be achieved.  Numerous factors could cause our actual results to differ materially from those in forward-looking statements, including, but not limited to, severe catastrophic events over which we have no control, the effectiveness of our loss limitation methods and pricing models, the adequacy of our liability for unpaid losses and loss adjustment expenses, our ability to maintain our A.M. Best Company, Inc. and Standard & Poor’s ratings, our ability to raise capital on acceptable terms if necessary, the cyclicality of the property and casualty reinsurance business, the highly competitive nature of the property and casualty reinsurance industry, our a bility to maintain our business relationships with reinsurance brokers, the availability of retrocessional reinsurance on acceptable terms, market volatility and interest rate and currency exchange rate fluctuation, tax, regulatory or legal restrictions or limitations applicable to us or the property and casualty reinsurance business generally, general political and economic conditions, including the effects of civil unrest, acts of terrorism, war or a prolonged United States or global economic downturn or recession; and changes in our plans, strategies, objectives, expectations or intentions, which may happen at any time at our discretion.  As a consequence, our future financial condition and results may differ from those expressed in any forward-looking statements made by, or on behalf of, us.  The foregoing factors should not be construed as exhaustive.  Additionally, forward-looking statements speak only as of the date they are made, and we undertake no obligation to revise or update forward-looking statements to reflect new information or circumstances after the date hereof or to reflect the occurrence of future events.

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Platinum Underwriters Holdings, Ltd.

Table of Contents

Section:	Page:
Financial Highlights:
a. Financial Highlights	3
Balance Sheet:
a. Condensed Consolidated Balance Sheets	4
Statements of Operations:
a. Condensed Consolidated Statements of Operations and Comprehensive Income - Summary	5
b. Condensed Consolidated Statements of Operations and Comprehensive Income - by Quarter	6
Other Company Data:
a. Computation of Net Operating Income and Net Operating Income per Diluted Common Share	7
b. Key Ratios, Share Data, Ratings	8
Earnings and Book Value Per Common Share Analysis:
a. Computation of Basic and Diluted Earnings Per Common Share - Summary	9
b. Computation of Basic and Diluted Earnings Per Common Share - by Quarter	10
c. Book Value Per Common Share	11
Cash Flow Statement:
a. Condensed Consolidated Statements of Cash Flows - Summary	12
b. Condensed Consolidated Statements of Cash Flows - by Quarter	13
Segment Data:
a. Segment Reporting - Three Month Summary	14
b. Segment Reporting - Six Month Summary	15
c. Property and Marine Segment - by Quarter	16
d. Casualty Segment - by Quarter	17
e. Finite Risk Segment - by Quarter	18
Net Premiums Written Data:
a. Net Premiums Written - Supplemental Information	19
b. Premiums by Line of Business - Three Month Summary	20
c. Premiums by Line of Business - Six Month Summay	21
Investments:
a. Investment Portfolio	22
b. Available-for-Sale Security Detail	23
c. Corporate Bonds Detail	24
d. Net Realized Gains on Investments and Net Impairment Losses on Investments	25
Loss Reserves:
a. Analysis of Losses and Loss Adjustment Expenses	26
b. Summary of Favorable (Unfavorable) Development of Losses and Related Premiums & Commissions	27
Exposures:
a. Estimated Exposures to Peak Zone Property Catastrophe Losses	28

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Platinum Underwriters Holdings, Ltd.

Financial Highlights

June 30, 2010

($ in thousands, except share data)

	Three Months Ended						Six Months Ended
	June 30,			June 30,			June 30,			June 30,
	2010			2009			2010			2009
Highlights
Net premiums written	$	151,718			208,117			399,145		$	453,389
Net premiums earned		191,432			232,462			411,610			480,214
Underwriting income		62,182			53,526			64,956			102,830
Net investment income		35,372			44,077			72,877			78,323
Net operating income (a)		83,677			90,937			106,976			159,483
Net realized gains on investments		49,489			10,794			54,946			31,364
Net impairment losses on investments		(3,410	)		(3,256	)		(21,512	)		(6,664	)
Net income attributable to common shareholders	$	124,139			98,130			139,560		$	181,751
Total assets	$	4,934,749			4,968,138			4,934,749		$	4,968,138
Investments and cash		4,528,013			4,399,258			4,528,013			4,399,258
Total shareholders' equity		2,105,435			1,952,704			2,105,435			1,952,704
Unpaid losses and loss adjustment expenses	$	2,224,026			2,394,330			2,224,026		$	2,394,330
Per share data
Common shares outstanding		41,095			49,778			41,095			49,778
Weighted average common shares outstanding - basic		43,225			50,580			44,322			50,105
Adjusted weighted average common shares outstanding - diluted		46,249			51,594			47,365			52,744
Net income per common share - basic	$	2.87			1.94			3.15		$	3.63
Net income per common share - diluted		2.68			1.90			2.95			3.47
Operating income per common share - diluted		1.81			1.76			2.26			3.02
Dividends per common share		0.08			0.08			0.16			0.16
Book value per common share	$	51.23			39.23			51.23		$	39.23

(a) See computation of net operating income on page 7.

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Platinum Underwriters Holdings, Ltd.

Condensed Consolidated Balance Sheets

($ in thousands, except share data)

	June 30,		March 31,		December 31,		September 30,		June 30,
	2010		2010		2009		2009		2009
Assets
Investments	$	3,335,914		3,754,054		3,660,515		3,953,620	$	4,049,472
Cash, cash equivalents and short-term investments		1,192,099		761,774		709,134		460,171		349,786
Reinsurance premiums receivable		160,729		320,724		269,912		272,489		261,817
Accrued investment income		28,373		32,031		29,834		32,646		33,813
Reinsurance balances (prepaid and recoverable)		28,036		28,025		29,710		31,171		24,715
Deferred acquisition costs		38,994		43,381		40,427		45,581		43,720
Funds held by ceding companies		85,030		85,695		84,478		85,211		120,232
Other assets		65,574		68,346		197,568		276,733		84,583
Total assets	$	4,934,749		5,094,030		5,021,578		5,157,622	$	4,968,138
Liabilities
Unpaid losses and loss adjustment expenses	$	2,224,026		2,378,253		2,349,336		2,373,151	$	2,394,330
Unearned premiums		168,545		205,606		180,609		209,951		190,757
Debt obligations		250,000		250,000		250,000		250,000		250,000
Commissions payable		57,370		96,451		90,461		93,013		121,780
Other liabilities		129,373		80,076		73,441		61,442		58,567
Total liabilities		2,829,314		3,010,386		2,943,847		2,987,557		3,015,434
Total shareholders' equity		2,105,435		2,083,644		2,077,731		2,170,065		1,952,704
Total liabilities and shareholders' equity	$	4,934,749		5,094,030		5,021,578		5,157,622	$	4,968,138
Book value per common share  (a)	$	51.23		46.59		45.22		43.55	$	39.23

(a) Book value per common share is determined by dividing shareholders' equity by actual common shares outstanding.

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Platinum Underwriters Holdings, Ltd.

Condensed Consolidated Statements of Operations and Comprehensive Income - Summary

($ in thousands, except share data)

	Three Months Ended						Six Months Ended
	June 30,			June 30,			June 30,			June 30,
	2010			2009			2010			2009
Revenue
Net premiums earned	$	191,432			232,462			411,610		$	480,214
Net investment income		35,372			44,077			72,877			78,323
Net realized gains on investments		49,489			10,794			54,946			31,364
Net impairment losses on investments		(3,410	)		(3,256	)		(21,512	)		(6,664	)
Other income (expense)		(144	)		5,212			129			5,444
Total revenue		272,739			289,289			518,050			588,681
Expenses
Net losses and loss adjustment expenses		71,475			124,945			236,043			269,109
Net acquisition expenses		44,088			38,338			81,417			78,494
Net changes in fair value of derivatives		30			106			2,345			2,523
Operating expenses		20,160			22,906			41,901			43,774
Net foreign currency exchange (gains) losses		(67	)		(537	)		(1,296	)		459
Interest expense		4,709			4,756			9,469			9,511
Total expenses		140,395			190,514			369,879			403,870
Income before income tax expense		132,344			98,775			148,171			184,811
Income tax expense		8,205			645			8,611			1,759
Net income		124,139			98,130			139,560			183,052
Preferred dividends		-			-			-			1,301
Net income attributable to common shareholders	$	124,139			98,130			139,560		$	181,751
Basic
Weighted average common shares outstanding		43,225			50,580			44,322			50,105
Basic earnings per common share	$	2.87			1.94			3.15		$	3.63
Diluted
Adjusted weighted average common shares outstanding		46,249			51,594			47,365			52,744
Diluted earnings per common share	$	2.68			1.90			2.95		$	3.47
Comprehensive income
Net income	$	124,139			98,130			139,560		$	183,052
Other comprehensive income, net of deferred taxes		34,833			64,958			82,705			63,382
Comprehensive income	$	158,972			163,088			222,265		$	246,434

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Platinum Underwriters Holdings, Ltd.

Condensed Consolidated Statements of Operations and Comprehensive Income - by Quarter

($ in thousands, except share data)

	Three Months Ended
	June 30,			March 31,			December 31,			September 30,			June 30,
	2010			2010			2009			2009			2009
Revenue
Net premiums earned	$	191,432			220,178			227,584			229,538		$	232,462
Net investment income		35,372			37,505			40,871			44,747			44,077
Net realized gains on investments		49,489			5,457			24,713			22,553			10,794
Net impairment losses on investments		(3,410	)		(18,102	)		(5,864	)		(5,075	)		(3,256	)
Other income (expense)		(144	)		273			(1,138	)		(1,222	)		5,212
Total revenue		272,739			245,311			286,166			290,541			289,289
Expenses
Net losses and loss adjustment expenses		71,475			164,568			109,993			99,240			124,945
Net acquisition expenses		44,088			37,329			47,916			50,009			38,338
Net changes in fair value of derivatives		30			2,315			2,913			4,305			106
Operating expenses		20,160			21,741			25,698			25,210			22,906
Net foreign currency exchange gains		(67	)		(1,229	)		(242	)		(616	)		(537	)
Interest expense		4,709			4,760			4,759			4,757			4,756
Total expenses		140,395			229,484			191,037			182,905			190,514
Income before income tax expense		132,344			15,827			95,129			107,636			98,775
Income tax expense (benefit)		8,205			406			4,358			(1,832	)		645
Net income		124,139			15,421			90,771			109,468			98,130
Preferred dividends		-			-			-			-			-
Net income attributable to common shareholders	$	124,139			15,421			90,771			109,468		$	98,130
Basic
Weighted average common shares outstanding		43,225			45,431			48,294			49,660			50,580
Basic earnings per common share	$	2.87			0.34			1.88			2.20		$	1.94
Diluted
Adjusted weighted average common shares outstanding		46,249			48,494			51,466			52,039			51,594
Diluted earnings per common share	$	2.68			0.32			1.76			2.10		$	1.90
Comprehensive income
Net income	$	124,139			15,421			90,771			109,468		$	98,130
Other comprehensive income (loss), net of deferred taxes		34,833			47,872			(36,726	)		106,570			64,958
Comprehensive income	$	158,972			63,293			54,045			216,038		$	163,088

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Platinum Underwriters Holdings, Ltd.

Computation of Net Operating Income and Net Operating Income per Diluted Common Share

($ in thousands, except share data)

	Three Months Ended						Six Months Ended
	June 30,			June 30,			June 30,			June 30,
	2010			2009			2010			2009
Net income attributable to common shareholders	$	124,139			98,130			139,560		$	181,751
Adjustments for:
Net realized gains on investments, net of tax		(43,382	)		(9,633	)		(48,541	)		(28,796	)
Net impairment losses on investments, net of tax		2,966			2,985			17,227			6,084
Net foreign currency exchange (gains) losses, net of tax		(46	)		(544	)		(1,270	)		443
Net operating income (a)	$	83,677			90,937			106,976		$	159,483
Per diluted common share:
Net income attributable to common shareholders	$	2.68			1.90			2.95		$	3.45
Less:
Net realized gains on investments		(0.94	)		(0.19	)		(1.02	)		(0.55	)
Net impairment losses on investments		0.06			0.06			0.36			0.12
Net foreign currency exchange (gains) losses		(0.00	)		(0.01	)		(0.03	)		0.01
Net operating income (b)	$	1.81			1.76			2.26		$	3.02
Adjusted weighted average common shares outstanding - diluted		46,249			51,594			47,365			52,744

(a) Operating income represents net income after taxes excluding net realized gains and losses on investments, net impairment losses on investments and net foreign exchange gains and losses.

(b) Operating income per diluted common share is calculated by dividing operating income by diluted weighted average shares outstanding for the period.

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Platinum Underwriters Holdings, Ltd.

Key Ratios, Share Data, Ratings

	As of and for the Three Months Ended
	June 30,			March 31,			December 31,			September 30,			June 30,
	2010			2010			2009			2009			2009
Key Ratios
Combined ratio (%)		67.4	%		98.7	%		77.3	%		72.3	%		76.9	%
Invested assets to shareholders' equity ratio	2.15:1			2.17:1			2.10:1			2.03:1			2.25:1
Debt to total capital (%)		10.6	%		10.7	%		10.7	%		10.3	%		11.3	%
Net premiums written (annualized) to shareholders' equity		0.29			0.47			0.39			0.45			0.43
Share Data
Book value per common share (a)	$	51.23			46.59			45.22			43.55		$	39.23
Common shares outstanding (000's)		41,095			44,722			45,943			49,827			49,778
Market Price Per Common Share
High	$	39.28			38.89			39.45			36.87		$	30.67
Low		35.06			34.60			34.63			28.07			27.12
Close	$	36.29			37.08			38.29			35.84		$	28.59
Industry Ratings
Financial Strength Rating
A.M. Best Company, Inc.		A			A			A			A			A
Standard & Poor's Ratings Services		A			A			A			n/a			n/a
Counterparty Credit Ratings (senior unsecured)
A.M. Best Company, Inc.	bbb			bbb			bbb			bbb			bbb
Standard & Poor's Ratings Services	BBB+			BBB+			BBB+			BBB			BBB
Supplemental Data
Total employees		145			145			146			146			146
See Definitions and Presentation on page 1.

(a) Book value per common share is determined by dividing shareholders' equity by actual common shares outstanding.

n/a = not applicable

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Platinum Underwriters Holdings, Ltd.

Computation of Basic and Diluted Earnings Per Common Share - Summary

($ in thousands, except share data)

	Three Months Ended				Six Months Ended
	June 30,		June 30,		June 30,		June 30,
	2010		2009		2010		2009
Earnings
Basic
Net income attributable to common shareholders	$	124,139		98,130		139,560	$	181,751
Diluted
Net income attributable to common shareholders		124,139		98,130		139,560		181,751
Effect of dilutive securities:
Preferred share dividends		-		-		-		1,301
Adjusted net income for diluted earnings per common share	$	124,139		98,130		139,560	$	183,052
Common Shares
Basic
Weighted average common shares outstanding		43,225		50,580		44,322		50,105
Diluted
Weighted average common shares outstanding		43,225		50,580		44,322		50,105
Effect of dilutive securities:
Conversion of preferred shares		-		-		-		1,525
Common share options		2,583		665		2,562		738
Restricted common shares and common share units		441		349		481		376
Adjusted weighted average common shares outstanding		46,249		51,594		47,365		52,744
Earnings Per Common Share
Basic earnings per common share	$	2.87		1.94		3.15	$	3.63
Diluted earnings per common share	$	2.68		1.90		2.95	$	3.47

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Platinum Underwriters Holdings, Ltd.

Computation of Basic and Diluted Earnings Per Common Share - by Quarter

($ in thousands, except share data)

	Three Months Ended
	June 30,		March 31,		December 31,		September 30,		June 30,
	2010		2010		2009		2009		2009
Earnings
Basic
Net income attributable to common shareholders	$	124,139		15,421		90,771		109,468	$	98,130
Diluted
Net income attributable to common shareholders		124,139		15,421		90,771		109,468		98,130
Effect of dilutive securities:
Preferred share dividends		-		-		-		-		-
Adjusted net income for diluted earnings per common share	$	124,139		15,421		90,771		109,468	$	98,130
Common Shares
Basic
Weighted average common shares outstanding		43,225		45,431		48,294		49,660		50,580
Diluted
Weighted average common shares outstanding		43,225		45,431		48,294		49,660		50,580
Effect of dilutive securities:
Conversion of preferred shares		-		-		-		-		-
Common share options		2,583		2,540		2,623		1,950		665
Restricted common shares and common share units		441		523		549		429		349
Adjusted weighted average common shares outstanding		46,249		48,494		51,466		52,039		51,594
Earnings Per Common Share
Basic earnings per common share	$	2.87		0.34		1.88		2.20	$	1.94
Diluted earnings per common share	$	2.68		0.32		1.76		2.10	$	1.90

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Platinum Underwriters Holdings, Ltd.

Book Value Per Common Share

($ and share data in thousands)

	June 30,		December 31,
	2010		2009
Price per share at period end	$	36.29	$	38.29
Shareholders' equity	$	2,105,435	$	2,077,731
Add: Assumed exercise of share options		50,396		69,647
Shareholders' equity - diluted	$	2,155,831	$	2,147,378
Basic common shares outstanding		41,095		45,943
Add: Shareholder share options (a)		2,282		2,529
Add: Management and directors' options (b)		1,689		2,238
Add: Directors' and officers' restricted common share units (c)		856		933
Diluted common shares outstanding		45,922		51,643
Book Value Per Common Share
Basic book value per common share	$	51.23	$	45.22
Fully converted book value per common share	$	46.95	$	41.58
See Definitions and Presentation on page 1.

(a) Options with a price of $27.00.

(b) Options with a price below $36.29, the closing share price at June 30, 2010.

(c) As of June 30, 2010 there were 41,095 common shares issued and outstanding.  Included in this number were 309 of restricted common shares issued but unvested.

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Platinum Underwriters Holdings, Ltd.

Condensed Consolidated Statements of Cash Flows - Summary

($ in thousands)

	Three Months Ended						Six Months Ended
	June 30,			June 30,			June 30,			June 30,
	2010			2009			2010			2009
Net cash provided by (used in) operating activities	$	(12,897	)		54,292			21,527		$	323,886
Net cash provided by (used in) investing activities		728,210			9,821			607,150			(694,960	)
Net cash used in financing activities		(140,564	)		(43,743	)		(200,627	)		(110,698	)
Effect of exchange rate changes on foreign currency cash		(5,517	)		6,485			(8,560	)		4,692
Net increase (decrease) in cash and cash equivalents	$	569,232			26,855			419,490		$	(477,080	)

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Platinum Underwriters Holdings, Ltd.

Condensed Consolidated Statements of Cash Flows - by Quarter

($ in thousands)

		Three Months Ended
		June 30,	March 31,	December 31,	September 30,		June 30,
		2010	2010	2009	2009		2009
Net cash provided by (used in) operating activities	$	(12,897)	34,424	54,720	98,591	$	54,292
Net cash provided by (used in) investing activities		728,210	(121,060)	365,976	(21,305)		9,821
Net cash used in financing activities		(140,564)	(60,063)	(150,835)	(2,705)		(43,743)
Effect of exchange rate changes on foreign currency cash		(5,517)	(3,043)	640	1,765		6,485
Net increase (decrease) in cash and cash equivalents	$	569,232	(149,742)	270,501	76,346	$	26,855

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Platinum Underwriters Holdings, Ltd.

Segment Reporting - Three Month Summary

($ in thousands)

	Three Months Ended June 30, 2010												Three Months Ended June 30, 2009
	Property and Marine			Casualty			Finite Risk			Total			Property and Marine			Casualty			Finite Risk			Total
Net premiums written	$	74,105			72,628			4,985		$	151,718		$	113,405			87,459			7,253		$	208,117
Net premiums earned		100,550			85,166			5,716			191,432			128,316			99,161			4,985			232,462
Net losses and loss adjustment expenses		35,010			40,058			(3,593	)		71,475			62,807			61,042			1,096			124,945
Net acquisition expenses		17,218			18,752			8,118			44,088			13,526			20,406			4,406			38,338
Other underwriting expenses		7,720			5,654			313			13,687			9,123			6,130			400			15,653
Total underwriting expenses		59,948			64,464			4,838			129,250			85,456			87,578			5,902			178,936
Segment underwriting income (loss)	$	40,602			20,702			878			62,182		$	42,860			11,583			(917	)		53,526
Net investment income											35,372												44,077
Net realized gains on investments											49,489												10,794
Net impairment losses on investments											(3,410	)											(3,256	)
Net changes in fair value of derivatives											(30	)											(106	)
Net foreign currency exchange gains											67												537
Other income (expense)											(144	)											5,212
Corporate expenses not allocated to segments											(6,473	)											(7,253	)
Interest expense											(4,709	)											(4,756	)
Income before income tax expense										$	132,344											$	98,775
GAAP underwriting ratios:
Net loss and loss adjustment expense		34.8	%		47.0	%		(62.9	%)		37.3	%		48.9	%		61.6	%		22.0	%		53.7	%
Net acquisition expense		17.1	%		22.0	%		142.0	%		23.0	%		10.5	%		20.6	%		88.4	%		16.5	%
Other underwriting expense		7.7	%		6.6	%		5.5	%		7.1	%		7.1	%		6.2	%		8.0	%		6.7	%
Combined		59.6	%		75.6	%		84.6	%		67.4	%		66.5	%		88.4	%		118.4	%		76.9	%
Statutory underwriting ratios:
Net loss and loss adjustment expense		34.8	%		47.0	%		(62.9	%)		37.3	%		48.9	%		61.6	%		22.0	%		53.7	%
Net acquisition expense		20.3	%		23.3	%		159.0	%		26.3	%		10.0	%		20.4	%		66.3	%		16.4	%
Other underwriting expense		10.4	%		7.8	%		6.3	%		9.0	%		8.0	%		7.0	%		5.5	%		7.5	%
Combined		65.5	%		78.1	%		102.4	%		72.6	%		66.9	%		89.0	%		93.8	%		77.6	%
See Definitions and Presentation on page 1.

The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

The Statutory underwriting ratios are based on statutory accounting principles and are calculated as follows:

 (1) Net losses & LAE are divided by net premiums earned;

 (2) Net acquisition expenses are divided by net premiums written and exclude changes in deferred acquisition costs; and

 (3) Other underwriting expenses are divided by net premiums written.

- 14 -

Platinum Underwriters Holdings, Ltd.

Segment Reporting - Six Month Summary

($ in thousands)

	Six Months Ended June 30, 2010												Six Months Ended June 30, 2009
	Property and Marine			Casualty			Finite Risk			Total			Property and Marine			Casualty			Finite Risk			Total
Net premiums written	$	220,890			166,379			11,876		$	399,145		$	255,140			185,473			12,776		$	453,389
Net premiums earned		228,356			173,068			10,186			411,610			261,987			209,121			9,106			480,214
Net losses and loss adjustment expenses		161,637			71,588			2,818			236,043			140,258			120,183			8,668			269,109
Net acquisition expenses		33,449			36,479			11,489			81,417			30,890			46,627			977			78,494
Other underwriting expenses		16,419			12,124			651			29,194			17,282			11,799			700			29,781
Total underwriting expenses		211,505			120,191			14,958			346,654			188,430			178,609			10,345			377,384
Segment underwriting income (loss)	$	16,851			52,877			(4,772	)		64,956		$	73,557			30,512			(1,239	)		102,830
Net investment income											72,877												78,323
Net realized gains on investments											54,946												31,364
Net impairment losses on investments											(21,512	)											(6,664	)
Net changes in fair value of derivatives											(2,345	)											(2,523	)
Net foreign currency exchange gains (losses)											1,296												(459	)
Other income											129												5,444
Corporate expenses not allocated to segments											(12,707	)											(13,993	)
Interest expense											(9,469	)											(9,511	)
Income before income tax expense										$	148,171											$	184,811
GAAP underwriting ratios:
Net loss and loss adjustment expense		70.8	%		41.4	%		27.7	%		57.3	%		53.5	%		57.5	%		95.2	%		56.0	%
Net acquisition expense		14.6	%		21.1	%		112.8	%		19.8	%		11.8	%		22.3	%		10.7	%		16.3	%
Other underwriting expense		7.2	%		7.0	%		6.4	%		7.1	%		6.6	%		5.6	%		7.7	%		6.2	%
Combined		92.6	%		69.5	%		146.9	%		84.2	%		71.9	%		85.4	%		113.6	%		78.5	%
Statutory underwriting ratios:
Net loss and loss adjustment expense		70.8	%		41.4	%		27.7	%		57.3	%		53.5	%		57.5	%		95.2	%		56.0	%
Net acquisition expense		15.1	%		21.1	%		99.6	%		20.1	%		11.3	%		22.1	%		12.7	%		15.7	%
Other underwriting expense		7.4	%		7.3	%		5.5	%		7.3	%		6.8	%		6.4	%		5.5	%		6.6	%
Combined		93.3	%		69.8	%		132.8	%		84.7	%		71.6	%		86.0	%		113.4	%		78.3	%
See Definitions and Presentation on page 1.

The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

The Statutory underwriting ratios are based on statutory accounting principles and are calculated as follows:

 (1) Net losses & LAE are divided by net premiums earned;

 (2) Net acquisition expenses are divided by net premiums written and exclude changes in deferred acquisition costs; and

 (3) Other underwriting expenses are divided by net premiums written.

- 15 -

Platinum Underwriters Holdings, Ltd.

Property and Marine Segment - by Quarter

($ in thousands)

	Three Months Ended
	June 30,			March 31,			December 31,			September 30,			June 30,
	2010			2010			2009			2009			2009
Net premiums written	$	74,105			146,785			114,423			147,448		$	113,405
Net premiums earned		100,550			127,806			133,934			132,567			128,316
Net losses and loss adjustment expenses		35,010			126,627			64,081			46,307			62,807
Net acquisition expenses		17,218			16,231			19,281			16,821			13,526
Other underwriting expenses		7,720			8,699			10,406			9,643			9,123
Total underwriting expenses		59,948			151,557			93,768			72,771			85,456
Segment underwriting income (loss)	$	40,602			(23,751	)		40,166			59,796		$	42,860
GAAP underwriting ratios:
Net loss and loss adjustment expense		34.8	%		99.1	%		47.8	%		34.9	%		48.9	%
Net acquisition expense		17.1	%		12.7	%		14.4	%		12.7	%		10.5	%
Other underwriting expense		7.7	%		6.8	%		7.8	%		7.3	%		7.1	%
Combined		59.6	%		118.6	%		70.0	%		54.9	%		66.5	%
Statutory underwriting ratios:
Net loss and loss adjustment expense		34.8	%		99.1	%		47.8	%		34.9	%		48.9	%
Net acquisition expense		20.3	%		12.5	%		15.0	%		12.8	%		10.0	%
Other underwriting expense		10.4	%		5.9	%		9.1	%		6.5	%		8.0	%
Combined		65.5	%		117.5	%		71.9	%		54.2	%		66.9	%
See Definitions and Presentation on page 1.

The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

The Statutory underwriting ratios are based on statutory accounting principles and are calculated as follows:

 (1) Net losses & LAE are divided by net premiums earned;

 (2) Net acquisition expenses are divided by net premiums written and exclude changes in deferred acquisition costs; and

 (3) Other underwriting expenses are divided by net premiums written.

- 16 -

Platinum Underwriters Holdings, Ltd.

Casualty Segment - by Quarter

($ in thousands)

	Three Months Ended
	June 30,			March 31,			December 31,			September 30,			June 30,
	2010			2010			2009			2009			2009
Net premiums written	$	72,628			93,751			82,548			88,467		$	87,459
Net premiums earned		85,166			87,902			89,189			90,591			99,161
Net losses and loss adjustment expenses		40,058			31,530			47,085			59,243			61,042
Net acquisition expenses		18,752			17,727			22,821			19,393			20,406
Other underwriting expenses		5,654			6,470			7,094			6,751			6,130
Total underwriting expenses		64,464			55,727			77,000			85,387			87,578
Segment underwriting income	$	20,702			32,175			12,189			5,204		$	11,583
GAAP underwriting ratios:
Net loss and loss adjustment expense		47.0	%		35.9	%		52.8	%		65.4	%		61.6	%
Net acquisition expense		22.0	%		20.2	%		25.6	%		21.4	%		20.6	%
Other underwriting expense		6.6	%		7.4	%		8.0	%		7.5	%		6.2	%
Combined		75.6	%		63.5	%		86.4	%		94.3	%		88.4	%
Statutory underwriting ratios:
Net loss and loss adjustment expense		47.0	%		35.9	%		52.8	%		65.4	%		61.6	%
Net acquisition expense		23.3	%		19.3	%		24.2	%		21.2	%		20.4	%
Other underwriting expense		7.8	%		6.9	%		8.6	%		7.6	%		7.0	%
Combined		78.1	%		62.1	%		85.6	%		94.2	%		89.0	%
See Definitions and Presentation on page 1.

The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

The Statutory underwriting ratios are based on statutory accounting principles and are calculated as follows:

 (1) Net losses & LAE are divided by net premiums earned;

 (2) Net acquisition expenses are divided by net premiums written and exclude changes in deferred acquisition costs; and

 (3) Other underwriting expenses are divided by net premiums written.

- 17 -

Platinum Underwriters Holdings, Ltd.

Finite Risk Segment - by Quarter

($ in thousands)

	Three Months Ended
	June 30,			March 31,			December 31,			September 30,			June 30,
	2010			2010			2009			2009			2009
Net premiums written	$	4,985			6,891			3,884			7,675		$	7,253
Net premiums earned		5,716			4,470			4,461			6,380			4,985
Net losses and loss adjustment expenses		(3,593	)		6,411			(1,173	)		(6,310	)		1,096
Net acquisition expenses		8,118			3,371			5,814			13,795			4,406
Other underwriting expenses		313			338			370			342			400
Total underwriting expenses		4,838			10,120			5,011			7,827			5,902
Segment underwriting income (loss)	$	878			(5,650	)		(550	)		(1,447	)	$	(917	)
GAAP underwriting ratios:
Net loss and loss adjustment expense		(62.9	%)		143.4	%		(26.3	%)		(98.9	%)		22.0	%
Net acquisition expense		142.0	%		75.4	%		130.3	%		216.2	%		88.4	%
Other underwriting expense		5.5	%		7.6	%		8.3	%		5.4	%		8.0	%
Combined		84.6	%		226.4	%		112.3	%		122.7	%		118.4	%
Statutory underwriting ratios:
Net loss and loss adjustment expense		(62.9	%)		143.4	%		(26.3	%)		(98.9	%)		22.0	%
Net acquisition expense		159.0	%		56.6	%		145.8	%		184.2	%		66.3	%
Other underwriting expense		6.3	%		4.9	%		9.5	%		4.5	%		5.5	%
Combined		102.4	%		204.9	%		129.0	%		89.8	%		93.8	%
See Definitions and Presentation on page 1.

The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

The Statutory underwriting ratios are based on statutory accounting principles and are calculated as follows:

 (1) Net losses & LAE are divided by net premiums earned;

 (2) Net acquisition expenses are divided by net premiums written and exclude changes in deferred acquisition costs; and

 (3) Other underwriting expenses are divided by net premiums written.

- 18 -

Platinum Underwriters Holdings, Ltd.

Net Premiums Written - Supplemental Information

($ in thousands)

	Three Months Ended				Six Months Ended
	June 30,		June 30,		June 30,		June 30,
	2010		2009		2010		2009
Property and Marine
Excess-of-loss	$	54,290		73,438		176,812	$	163,278
Proportional		19,815		39,967		44,078		91,862
Subtotal Property and Marine		74,105		113,405		220,890		255,140
Casualty
Excess-of-loss		70,183		76,927		150,014		162,251
Proportional		2,445		10,532		16,365		23,222
Subtotal Casualty		72,628		87,459		166,379		185,473
Finite Risk
Excess-of-loss		-		-		-		(8	)
Proportional		4,985		7,253		11,876		12,784
Subtotal Finite Risk		4,985		7,253		11,876		12,776
Combined Segments
Excess-of-loss		124,473		150,365		326,826		325,521
Proportional		27,245		57,752		72,319		127,868
Total	$	151,718		208,117		399,145	$	453,389
	Three Months Ended				Six Months Ended
	June 30,		June 30,		June 30,		June 30,
	2010		2009		2010		2009
Property and Marine
United States	$	39,994		79,758		121,682	$	169,905
International		34,111		33,647		99,208		85,235
Subtotal Property and Marine		74,105		113,405		220,890		255,140
Casualty
United States		60,367		76,620		142,748		162,533
International		12,261		10,839		23,631		22,940
Subtotal Casualty		72,628		87,459		166,379		185,473
Finite Risk
United States		4,985		7,253		11,876		12,776
International		-		-		-		-
Subtotal Finite Risk		4,985		7,253		11,876		12,776
Combined Segments
United States		105,346		163,631		276,306		345,214
International		46,372		44,486		122,839		108,175
Total	$	151,718		208,117		399,145	$	453,389

- 19 -

Platinum Underwriters Holdings, Ltd.

Premiums by Line of Business - Three Month Summary

($ in thousands)

	Three Months Ended June 30, 2010								Three Months Ended June 30, 2009
	Gross			Net			Net		Gross		Net		Net
	Premiums			Premiums			Premiums		Premiums		Premiums		Premiums
	Written			Written			Earned		Written		Written		Earned
Property and Marine
North American Property Proportional	$	1,980			1,980			2,217		1,732		1,732	$	2,827
North American Property Catastrophe		25,689			15,466			30,235		26,046		26,046		27,041
North American Property Risk		10,398			10,763			13,577		25,058		17,985		18,810
Other Property		12,561			12,561			12,388		35,385		35,385		35,351
Marine / Aviation Proportional		1,837			1,837			2,190		2,869		2,869		2,868
Marine / Aviation Excess		2,734			2,745			2,898		4,552		4,552		5,752
International Property Proportional		4,367			4,367			4,135		4,305		4,305		5,908
International Property Catastrophe		21,949			21,934			29,944		17,528		17,508		26,501
International Property Risk		2,452			2,452			2,966		3,023		3,023		3,258
Subtotal		83,967			74,105			100,550		120,498		113,405		128,316
Casualty
Clash		3,874			3,874			3,751		3,930		3,930		3,901
1st Dollar GL		2,884			2,884			2,740		3,785		3,785		4,521
1st Dollar Other		1,353			1,353			843		1,250		1,250		1,429
Casualty Excess		50,683			50,683			53,985		60,802		60,802		68,658
Accident & Health		5,732			5,732			9,568		5,087		5,087		6,648
International Casualty		7,716			7,716			6,002		8,066		8,066		9,308
International Motor		783			783			889		757		757		876
Financial Lines		(397	)		(397	)		7,388		3,782		3,782		3,820
Subtotal		72,628			72,628			85,166		87,459		87,459		99,161
Finite Risk
Finite Property		-			-			-		-		-		-
Finite Casualty		4,985			4,985			5,716		7,253		7,253		4,985
Subtotal		4,985			4,985			5,716		7,253		7,253		4,985
Total	$	161,580			151,718			191,432		215,210		208,117	$	232,462

- 20 -

Platinum Underwriters Holdings, Ltd.

Premiums by Line of Business - Six Month Summary

($ in thousands)

	Six Months Ended June 30, 2010						Six Months Ended June 30, 2009
	Gross		Net		Net		Gross			Net			Net
	Premiums		Premiums		Premiums		Premiums			Premiums			Premiums
	Written		Written		Earned		Written			Written			Earned
Property and Marine
North American Property Proportional	$	4,019		4,019		3,390		3,560			3,560		$	6,744
North American Property Catastrophe		68,034		57,809		68,125		55,837			54,586			52,881
North American Property Risk		29,348		27,494		30,921		43,147			35,447			36,452
Other Property		33,999		33,999		33,759		78,640			78,640			78,424
Marine / Aviation Proportional		3,016		3,016		3,830		6,110			6,110			5,720
Marine / Aviation Excess		6,458		6,469		6,735		8,820			8,858			12,186
International Property Proportional		8,169		8,169		7,494		8,893			8,893			11,487
International Property Catastrophe		78,081		74,527		68,855		54,797			52,917			52,233
International Property Risk		5,388		5,388		5,247		6,129			6,129			5,860
Subtotal		236,512		220,890		228,356		265,933			255,140			261,987
Casualty
Clash		7,766		7,766		7,583		8,353			8,353			8,226
1st Dollar GL		5,478		5,478		5,445		8,005			8,005			9,830
1st Dollar Other		2,630		2,630		1,937		2,797			2,797			2,999
Casualty Excess		106,262		106,262		112,707		121,959			121,959			142,545
Accident & Health		20,826		20,826		18,317		17,248			17,248			14,085
International Casualty		13,042		13,042		12,856		18,329			18,329			20,457
International Motor		1,847		1,847		1,829		1,602			1,602			1,602
Financial Lines		8,528		8,528		12,394		7,180			7,180			9,377
Subtotal		166,379		166,379		173,068		185,473			185,473			209,121
Finite Risk
Finite Property		-		-		-		(8	)		(8	)		(8	)
Finite Casualty		11,876		11,876		10,186		12,784			12,784			9,114
Subtotal		11,876		11,876		10,186		12,776			12,776			9,106
Total	$	414,767		399,145		411,610		464,182			453,389		$	480,214

- 21 -

Platinum Underwriters Holdings, Ltd.

Investment Portfolio

($ in thousands)

	June 30, 2010								December 31, 2009
			Weighted			Weighted Average					Weighted			Weighted Average
			Average			Market Yield					Average			Market Yield
	Fair Value		Book Yield			to Maturity			Fair Value		Book Yield			to Maturity
Available-for-sale securities
U.S. Government	$	1,056,045		2.7	%		2.4	%	$	608,697		2.9	%		3.0	%
U.S. Government agencies		100,893		0.9	%		0.5	%		101,082		0.6	%		0.2	%
Corporate bonds		472,446		5.1	%		3.2	%		476,986		5.1	%		3.7	%
Commercial mortgage-backed securities		217,300		4.9	%		5.5	%		215,020		5.5	%		7.0	%
Residential mortgage-backed securities		189,813		4.5	%		6.0	%		714,703		4.6	%		5.5	%
Asset-backed securities		29,410		1.4	%		9.9	%		59,699		2.6	%		6.6	%
Municipal bonds		1,029,585		4.6	%		3.8	%		759,501		4.2	%		3.4	%
Non-U.S. governments		76,967		2.9	%		1.7	%		578,364		3.1	%		2.5	%
Total Fixed Maturities		3,172,459		3.9	%		3.4	%		3,514,052		4.0	%		3.8	%
Preferred Stocks		2,090		26.6	%		10.3	%		3,897		29.8	%		13.2	%
Total	$	3,174,549		3.9	%		3.4	%	$	3,517,949		4.0	%		3.8	%
Trading securities
Insurance-linked securities	$	25,901		10.7	%		7.8	%	$	25,682		10.7	%		8.5	%
Non-U.S. dollar denominated securities:
U.S. Government agencies		15,254		1.9	%		1.4	%		16,423		1.9	%		1.8	%
Corporate bonds		64		4.5	%		2.0	%		77		4.5	%		2.1	%
Non-U.S. governments		120,146		3.6	%		1.9	%		100,384		4.6	%		3.1	%
Total	$	161,365		4.6	%		2.8	%	$	142,566		5.4	%		3.9	%
	June 30, 2010								December 31, 2009
	Amount		% of Total						Amount		% of Total
Credit quality of investment portfolio*
Aaa	$	1,781,755		53.4	%				$	2,341,963		64.0	%
Aa		676,748		20.3	%					517,404		14.1	%
A		512,333		15.3	%					404,711		11.1	%
Baa		261,976		7.9	%					315,275		8.6	%
Below investment grade		103,102		3.1	%					81,162		2.2	%
Total	$	3,335,914		100.0	%				$	3,660,515		100.0	%
Credit quality
Weighted average credit quality	Aa2								Aa2
* Rated using external rating agencies (primarily Moody's).
(Aaa-Best Quality; Aa-High Quality; A-Upper to Medium Quality, Baa - Investment Grade)

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Platinum Underwriters Holdings, Ltd.

Available-for-Sale Security Detail

($ in thousands)

	June 30, 2010
			Unrealized			Credit			Weighted
	Fair Value		Gain (Loss)			Quality	Duration		Average Life
Available-for-sale securities
U.S. Government	$	1,056,045	$	21,849		Aaa		6.3
U.S. Government agencies		100,893		893		Aaa		0.3
Corporate bonds:
Industrial		310,355		15,974		A3		3.4
Finance		15,236		(1,407	)	Baa2		6.6
Utilities		66,391		3,006		A3		4.2
Insurance		57,243		3,020		A3		4.5
Preferreds with maturity date		23,221		(3,294	)	Baa2		7.2
Subtotal		472,446		17,299		A3		3.9
Commercial mortgage-backed securities		217,300		(106	)	Aa2		3.8		4.7
Residential mortgage-backed securities:
U.S. Government agency residential mortgage-backed securities		93,620		3,813		Aaa		1.4		2.9
Non-agency residential mortgage-backed securities		89,117		(38,894	)	Ba2		-		3.5
Alt-A residential mortgage-backed securities		7,076		(6,319	)	Caa2		-		4.3
Subtotal		189,813		(41,400	)	A3		0.7		3.3
Asset-backed securities:
Asset-backed securities		19,595		(331	)	Aaa		-		4.9
Sub-prime asset-backed securities		9,815		(11,852	)	B2		-		10.7
Subtotal		29,410		(12,183	)	A2		-		6.8
Municipal bonds		1,029,585		37,435		Aa2		6.8
Non-U.S. governments		76,967		1,709		Aa1		2.4
Preferred stocks		2,090		1,278		Ba3		5.3
Total	$	3,174,549	$	26,774		Aa2		5.2

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Platinum Underwriters Holdings, Ltd.

Corporate Bonds Detail

($ in thousands)

	June 30, 2010
					Unrealized			Credit
	Par Value		Fair Value		Gain (Loss)			Quality
Largest Holdings by Issuer
Wal-Mart Stores, Inc.	$	16,950		19,315	$	596		Aa2
MetLife, Inc.		17,897		19,117		1,356			A1
Philip Morris International Inc.		14,000		15,903		1,269			A2
Hewlett-Packard Company		13,100		14,642		1,020			A2
BHP Billiton Limited		13,000		14,255		1,083			A1
Bank of America Corporation		17,500		13,918		(3,425	)	Baa3
Diageo plc		10,500		12,016		710			A3
Marathon Oil Corporation		10,000		11,643		730		Baa1
HCC Insurance Holdings, Inc.		10,000		10,245		167		Baa1
AT&T Inc.		9,250		10,203		864			A2
Anglo American plc		8,000		9,991		(41	)	Baa1
Consolidated Edison, Inc.		9,400		9,972		559			A3
Kraft Foods Inc.		9,200		9,815		256		Baa2
Rio Tinto plc		7,250		8,983		404		Baa1
Telefonica, S.A.		8,500		8,835		263		Baa1
The Southern Company		7,525		7,715		193			A2
Snap-On Incorporated		7,000		7,698		653		Baa1
Canadian National Railway Company		6,900		7,380		509			A3
EOG Resources, Inc.		6,660		7,139		272			A3
Pfizer Inc.	$	6,000		6,658	$	616			A1

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Platinum Underwriters Holdings, Ltd.

Net Realized Gains on Investments and Net Impairment Losses on Investments

($ in thousands)

	Three Months Ended					Six Months Ended
	June 30,		June 30,			June 30,		June 30,
	2010		2009			2010		2009
Net realized gains on investments by entity:
Subsidiary domiciled in Bermuda	$	32,041		7,485			36,646	$	24,022
Subsidiaries domiciled in the United States		17,448		3,316			18,300		7,338
Subsidiary domiciled in the United Kingdom		-		(7	)		-		4
Total	$	49,489		10,794			54,946	$	31,364
Net realized gains on investments by type:
Sale of securities	$	47,891		7,999			52,602	$	29,768
Mark-to-market on trading securities		1,598		2,795			2,344		1,596
Total	$	49,489		10,794			54,946	$	31,364
Net impairment losses on investments by entity:
Subsidiary domiciled in Bermuda	$	2,142		2,481			9,269	$	5,008
Subsidiaries domiciled in the United States		1,268		775			12,243		1,656
Total	$	3,410		3,256			21,512	$	6,664
Net impairment losses on investments by type of security:
Commercial mortgage-backed securities	$	-		345			7,731	$	980
Residential mortgage-backed securities		1,792		2,334			2,740		3,759
Asset-backed securities		1,618		577			11,041		717
Preferred stocks		-		-			-		1,208
Total	$	3,410		3,256			21,512	$	6,664

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Platinum Underwriters Holdings, Ltd.

Analysis of Losses and Loss Adjustment Expenses

($ in thousands)

	Analysis of Losses and Loss Adjustment Expenses
	Six Months Ended June 30, 2010 (a)												Twelve Months Ended December 31, 2009 (b)
	Gross			Ceded			Net			Paid to Incurred %			Gross			Ceded		Net			Paid to Incurred %
Paid losses and loss adjustment expenses	$	344,838			5,663		$	339,175			143.7	%	$	620,332			13,122	$	607,210			126.9	%
Change in unpaid losses and loss adjustment expenses		(104,546	)		(1,414	)		(103,132	)					(126,020	)		2,848		(128,868	)
Losses and loss adjustment expenses incurred	$	240,292			4,249		$	236,043					$	494,312			15,970	$	478,342
	Analysis of Unpaid Losses and Loss Adjustment Expenses
	As of June 30, 2010												As of December 31, 2009
	Gross			Ceded			Net			%			Gross			Ceded		Net			%
Outstanding losses and loss adjustment expenses	$	697,458			8,972		$	688,486			31.1	%	$	680,487			9,169	$	671,318			28.8	%
Incurred but not reported		1,526,568			3,883			1,522,685			68.9	%		1,668,849			5,159		1,663,690			71.2	%
Unpaid losses and loss adjustment expenses	$	2,224,026			12,855		$	2,211,171			100.0	%	$	2,349,336			14,328	$	2,335,008			100.0	%
(a) Gross and ceded losses and loss adjustment expenses incurred includes effects of foreign currency exchange rate gains and losses of $20,764 and $59, respectively.
(b) Gross and ceded losses and loss adjustment expenses incurred includes effects of foreign currency exchange rate gains and losses of $19 and $11,850, respectively.

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Platinum Underwriters Holdings, Ltd.

Summary of Favorable (Unfavorable) Development of Losses and Related Premiums & Commissions

($ in thousands)

	Three Months Ended June 30, 2010											Three Months Ended June 30, 2009
	Property and Marine			Casualty		Finite Risk			Total			Property and Marine			Casualty			Finite Risk			Total
Non-Catastrophe Favorable (Unfavorable) Development
Net loss development related to prior years	$	20,468			22,616		7,809		$	50,893		$	66			13,471			2,612		$	16,149
Net premium adjustments related to prior years' losses		546			136		-			682			616			450			-			1,066
Net commission adjustments related to prior years' losses		(2,999	)		648		(6,586	)		(8,937	)		5,308			3,920			(3,113	)		6,115
Net favorable (unfavorable) development		18,015			23,400		1,223			42,638			5,990			17,841			(501	)		23,330
Catastrophe Favorable (Unfavorable) Development
Net loss development related to prior years		(691	)		2		-			(689	)		(1,113	)		-			-			(1,113	)
Net premium adjustments related to prior years' losses		(1,874	)		-		-			(1,874	)		1,338			-			-			1,338
Net commission adjustments related to prior years' losses		-			-		-			-			-			-			-			-
Net favorable (unfavorable) development		(2,565	)		2		-			(2,563	)		225			-			-			225
Total net favorable (unfavorable) development	$	15,450			23,402		1,223		$	40,075		$	6,215			17,841			(501	)	$	23,555
	Six Months Ended June 30, 2010											Six Months Ended June 30, 2009
	Property and Marine			Casualty		Finite Risk			Total			Property and Marine			Casualty			Finite Risk			Total
Non-Catastrophe Favorable (Unfavorable) Development
Net loss development related to prior years	$	39,113			55,955		4,692		$	99,760		$	997			36,666			(2,225	)	$	35,438
Net premium adjustments related to prior years' losses		989			430		-			1,419			1,264			(156	)		-			1,108
Net commission adjustments related to prior years' losses		(3,854	)		3,566		(9,176	)		(9,464	)		5,699			3,631			1,596			10,926
Net favorable (unfavorable) development		36,248			59,951		(4,484	)		91,715			7,960			40,141			(629	)		47,472
Catastrophe Favorable (Unfavorable) Development
Net loss development related to prior years		(691	)		5		-			(686	)		(3,528	)		(57	)		59			(3,526	)
Net premium adjustments related to prior years' losses		(1,466	)		-		-			(1,466	)		1,698			-			-			1,698
Net commission adjustments related to prior years' losses		-			-		-			-			-			-			-			-
Net favorable (unfavorable) development		(2,157	)		5		-			(2,152	)		(1,830	)		(57	)		59			(1,828	)
Total net favorable (unfavorable) development	$	34,091			59,956		(4,484	)	$	89,563		$	6,130			40,084			(570	)	$	45,644

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Platinum Underwriters Holdings, Ltd.

Estimated Exposures to Peak Zone Property Catastrophe Losses

As of July 1, 2010

($ in millions)

Estimated Probable Maximum Losses by Zone and Peril
		20 Year Return Period					100 Year Return Period				250 Year Return Period
Zones	Perils	Estimated Gross Loss			Estimated Net Loss		Estimated Gross Loss		Estimated Net Loss		Estimated Gross Loss		Estimated Net Loss
United States / Caribbean	Hurricane	$	175			144		377		312		437	$	372
United States	Earthquake		12			12		234		234		305		305
Pan-European	Windstorm		135			92		279		195		336		250
Japan	Earthquake		13			13		132		132		282		282
Japan	Typhoon	$	6			6		66		66		75	$	75
Indicative Catastrophe Scenarios
Catastrophe Scenarios		Estimated Company Net Loss Interquartile Range
Category 3 U.S. / Caribbean Hurricane		$	12	-		33
Category 4 U.S. / Caribbean Hurricane			16	-		72
Magnitude 6.9 California Earthquake			0	-		3
Magnitude 7.5 California Earthquake		$	0	-		9

The Company has developed the estimates of losses expected from certain catastrophes for its portfolio of property, marine, workers’ compensation, personal accident contracts and catastrophe contributions from insurance-linked securities using commercially available catastrophe models, which are applied and adjusted by the Company.  These estimates include assumptions regarding the location, size and magnitude of an event, the frequency of events, the construction type and damageability of property in a zone, and the cost of rebuilding property in a zone, among other assumptions.  These estimates do not include any losses that may be expected to arise from the Company’s casualty portfolio as a result of such catastrophes.  Return period refers to the frequency with which losses of a given amount o r greater are expected to occur.

Gross loss estimates are before income tax and net of reinstatement premiums.  Net loss estimates are before income tax, net of reinstatement premiums, and net of retrocessional recoveries.  Ranges shown for indicative catastrophe scenarios are interquartile reflecting the middle 50% of indications.  That is, 25% of indications fall below the low end of a given range and 25% of indications fall above the high end of that range.  Thus, an actual event may produce losses that fall materially outside the indicated ranges.

The estimates set forth above are based on assumptions that are inherently subject to significant uncertainties and contingencies.  These uncertainties and contingencies can affect actual losses and could cause actual losses to differ materially from those expressed above.  In particular, modeled loss estimates do not necessarily accurately predict actual losses, and may significantly misestimate actual losses.  Such estimates, therefore, should not be considered as a representation of actual losses.  Investors should not rely on the foregoing information when considering investment in the Company.  The Company undertakes no duty to update or revise such information to reflect the occurrence of future events.

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