Exhibit 12

Arch Capital Group Ltd. and Subsidiaries

Computation of Ratio of Earnings to Fixed Charges and Preference Dividends

(in thousands, except ratios)

	Years Ended December 31,
	2010			2009			2008		2007			2006
Income before income taxes	$	850,456		$	897,653		$	304,505	$	873,544		$	739,893
Equity in net (income) loss of investees	(56,035		)	(183,038		)	166,326		(8,877		)	(3,102		)
Fixed charges	35,018			30,074			29,673		27,032			26,386
Income available for fixed charges	$	829,439		$	744,689		$	500,504	$	891,699		$	763,177
Fixed charges:
Interest and amortization on indebtedness	30,007			24,440			23,838		22,093			22,090
Estimate of interest component within rental expense net of sublease (income) (1)	5,011			5,634			5,835		4,939			4,296
Total fixed charges	35,018			30,074			29,673		27,032			26,386
Preference dividends	25,844			25,844			25,844		25,844			20,655
Total fixed charges and preference dividends	60,862			55,918			55,517		52,876			47,041
Ratio of earnings to fixed charges	23.7			24.8			16.9		33.0			28.9
Ratio of earnings to fixed charges and preference dividends	13.6			13.3			9.0		16.9			16.2

(1)  Represents a reasonable approximation of the interest cost component of rental expense net of sublease (income) incurred by the Company.