Fitch Ratings has affirmed the ratings of Allied World Assurance Company Holdings, Ltd (Allied World) as follows:

--Issuer Default Rating (IDR) at 'A';

--Senior debt at 'A-'.

Fitch has also affirmed the 'A+' Insurer Financial Strength (IFS) ratings of Allied World's property/casualty and reinsurance subsidiaries. A full list of ratings follows at the end of this release.

The Rating Outlook is Stable.

KEY RATING DRIVERS

Fitch's affirmation of Allied World's ratings reflects the company's consistently strong underwriting profitability, low financial leverage, solid capitalization and well-managed reserve risk. The ratings also reflect potential volatility from large catastrophe-related events, recent significant growth rate in primary premiums offset somewhat by decreases in the reinsurance portfolio, potential adverse development due to the relatively large proportion of its reserves derived from longer duration casualty lines of business, and allocation to higher yielding alternative investments.

In addition, the ratings reflect Fitch's negative sector outlook on global reinsurance, as the fundamentals of the reinsurance sector have deteriorated with declining premium pricing and weakening of terms and conditions, particularly for property catastrophe risk. This is leading to consolidation in the reinsurance sector as companies aim to enhance their relative competitive positions.

AWH's market position and size/scale is characterized as 'Medium' by Fitch when measured by net written premium and equity. Allied World maintains a unique portfolio of business lines relative to its Bermuda peers and includes a mix of primary insurance and reinsurance business.

Allied World reported 8.8% growth in North American Insurance gross premiums written (GPW) in the first half of 2015, particularly in its General Casualty book of business. Increases in GPW in the Global Markets Insurance segment were largely a result of the inclusion of premium from the acquisition of the Hong Kong and Singapore operations of Royal & Sun Alliance Insurance Plc. (RSA) into Allied World's results at mid-year 2015. Premium increases were largely offset however with a 13.9% decrease in reinsurance GPW. Total growth in net premiums written in the first half of 2015 (1H15) was limited to 3.8%.

Allied World reported a calendar-year combined ratio of 94% through six-months 2015, following a six-month 2014 ratio of 85.1% as the company reported catastrophe losses of $25 million related to the New South Wales storms and $20 million of non-catastrophe weather and fire related losses in the period. Allied World reported decreased net earnings of $134 million through six-months 2015, generating an annualized net return on equity of 7.2%.

Allied World's results have benefited from favorable reserve development that averaged 13.7% of net earned premiums from 2010-2014. Allied World reported $85 million of reserve releases through the first six months of 2015, representing 7% of net earned premium.

Fitch views Allied World's capitalization as strong, with metrics such as GAAP operating (net premiums written-to-total shareholders' equity) and net leverage ratios of 0.6x and 2.2x as of year-end 2014, which are at median guidelines for the 'AA' rating category. Allied World has historically used a conservative amount of operating leverage relative to (re)insurer peers, averaging 0.54x in the five years between 2010-2014.

Total shareholders' equity decreased by 4.1% to $3.6 billion at June 30, 2015, as positive net earnings were offset by $246 million of share repurchase activity during the first six months of the year. Allied World uses a moderate amount of financial leverage in its capital structure. At June 30, 2015, debt securities represented approximately 18.5% of the company's almost $4.5 billion of capital.

RATING SENSITIVITIES

Key rating triggers that could result in a downgrade include:

--Deterioration in reinsurance sector fundamentals or consolidation in the reinsurance landscape that Fitch viewed as weakening Allied World's competitive position, operating profile or overall profitability;

--Failure to maintain a multi-year average calendar-year combined ratio of 100% or better;

--Growth in premiums considerably greater than peers;

--Significant adverse reserve development;

--Material loss of capital that leads to an increase in underwriting leverage above a 1.0x net written premiums-to-equity ratio or financial leverage increasing above 25%;

--Catastrophe loss experience that greatly exceeds the company's probable maximum loss estimates.

Key rating triggers that could lead to an upgrade include:

--Enhanced scale and relative competitive position with maintenance of current operating performance in the challenging reinsurance environment;

--Material improvement in key financial metrics (e.g. net premiums written to equity) to more overcapitalized levels;

--Underwriting results and returns on capital in line with higher rated property/casualty (re)insurer peers.

FULL LIST OF RATING ACTIONS

Fitch affirms the following ratings with a Stable Outlook:

Allied World Assurance Company Holdings, Ltd

--IDR at 'A';

--$500 million 7.50% senior notes due Aug. 1, 2016 at 'A-';

--$300 million 5.50% senior notes due Nov. 1, 2020 at 'A-'.

Allied World Assurance Company, Ltd

Allied World Assurance Company (U.S.) Inc.

Allied World National Assurance Company

Allied World Insurance Company

--IFS at 'A+'.

Additional information is available on www.fitchratings.com

Applicable Criteria

Insurance Rating Methodology (pub. 14 Jul 2015)

https://www.fitchratings.com/creditdesk/reports/report_frame.cfm?rpt_id=868367

Additional Disclosures

Dodd-Frank Rating Information Disclosure Form

https://www.fitchratings.com/creditdesk/press_releases/content/ridf_frame.cfm?pr_id=988761

Solicitation Status

https://www.fitchratings.com/gws/en/disclosure/solicitation?pr_id=988761

Endorsement Policy

https://www.fitchratings.com/jsp/creditdesk/PolicyRegulation.faces?context=2&detail=31

ALL FITCH CREDIT RATINGS ARE SUBJECT TO CERTAIN LIMITATIONS AND DISCLAIMERS. PLEASE READ THESE LIMITATIONS AND DISCLAIMERS BY FOLLOWING THIS LINK: HTTP://FITCHRATINGS.COM/UNDERSTANDINGCREDITRATINGS. IN ADDITION, RATING DEFINITIONS AND THE TERMS OF USE OF SUCH RATINGS ARE AVAILABLE ON THE AGENCY'S PUBLIC WEBSITE 'WWW.FITCHRATINGS.COM'. PUBLISHED RATINGS, CRITERIA AND METHODOLOGIES ARE AVAILABLE FROM THIS SITE AT ALL TIMES. FITCH'S CODE OF CONDUCT, CONFIDENTIALITY, CONFLICTS OF INTEREST, AFFILIATE FIREWALL, COMPLIANCE AND OTHER RELEVANT POLICIES AND PROCEDURES ARE ALSO AVAILABLE FROM THE 'CODE OF CONDUCT' SECTION OF THIS SITE. FITCH MAY HAVE PROVIDED ANOTHER PERMISSIBLE SERVICE TO THE RATED ENTITY OR ITS RELATED THIRD PARTIES. DETAILS OF THIS SERVICE FOR RATINGS FOR WHICH THE LEAD ANALYST IS BASED IN AN EU-REGISTERED ENTITY CAN BE FOUND ON THE ENTITY SUMMARY PAGE FOR THIS ISSUER ON THE FITCH WEBSITE.

Fitch RatingsPrimary AnalystChristopher A. Grimes, CFADirector+1-312-368-3263Fitch Ratings, Inc.70 W. Madison StreetChicago, IL 60602orSecondary AnalystBrian C. Schneider, CPA, CPCU, AReSenior Director+1-312-606-2321orCommittee ChairpersonMark E. Rouck, CFA, CPASenior Director+1-312-368-2085orMedia Relations:Alyssa Castelli, +1-212-908-0540alyssa.castelli@fitchratings.com