8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

Current Report

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 11, 2015

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, AG

(Exact Name of Registrant as Specified in Charter)

Switzerland	001-32938	98-0681223
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(I.R.S. Employer Identification No.)

Gubelstrasse 24Park Tower, 15th Floor

6300 Zug, Switzerland

(Address of Principal Executive Offices and Zip Code)

Registrant’s telephone number, including area code: 41-41-768-1080

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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Item 7.01. Regulation FD Disclosure.

On or after May 13, 2015, representatives of Allied World Assurance Company Holdings, AG (the “Company”) will present to various investors the information about the Company described in the slides attached to this report as Exhibit 99.1, which are incorporated by reference herein.

The information in Item 7.01 of this report is being furnished, not filed, pursuant to Regulation FD. Accordingly, the information in Item 7.01 of this report will not be incorporated by reference into any registration statement filed by the Company under the Securities Act of 1933, as amended, unless specifically identified therein as being incorporated therein by reference. The furnishing of the information in this report is not intended to, and does not, constitute a determination or admission by the Company that the information in this report is material or complete, or that investors should consider this information before making an investment decision with respect to any security of the Company.

Cautionary Statement Regarding Forward-Looking Statements

Any forward-looking statements made in the presentation in Exhibit 99.1 reflect our current views with respect to future events and financial performance and are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Such statements involve risks and uncertainties, which may cause actual results to differ materially from those set forth in these statements. For example, our forward-looking statements could be affected by risks that the acquisitions of the Hong Kong and Singapore operations of Royal & Sun Alliance Insurance plc (“RSA”) disrupt our current plans and operations; the ability to retain key personnel; the ability to recognize the benefits of the RSA acquisitions; the amount of costs, fees, expenses and charges related to the RSA acquisitions; pricing and policy term trends; increased competition; the adequacy of our loss reserves; negative rating agency actions; greater frequency or severity of unpredictable catastrophic events; the impact of acts of terrorism and acts of war; the Company or its subsidiaries becoming subject to significant income taxes in the United States or elsewhere; changes in regulations or tax laws; changes in the availability, cost or quality of reinsurance or retrocessional coverage; adverse general economic conditions; and judicial, legislative, political and other governmental developments, as well as management’s response to these factors, and other factors identified in our filings with the U.S. Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date on which they are made. We are under no obligation (and expressly disclaim any such obligation) to update or revise any forward-looking statement that may be made from time to time, whether as a result of new information, future developments or otherwise.

Item 9.01. Financial Statements and Exhibits.

(d)Exhibits

ExhibitNumber	Description
99.1	Slides from presentation by management.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, AG

Dated: May 11, 2015             By: /s/ Wesley D. Dupont          

Name: Wesley D. Dupont

Title: Executive Vice President & General Counsel

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EXHIBIT INDEX

ExhibitNumber	Description
99.1	Slides from presentation by management.

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EX-99.1

I N V E S T O R P R E S E N T A T I O N 1 S T Q U A R T E R 2 0 1 5

Cautionary note regarding forward-looking statements Any forward-looking statements made in this presentation reflect our current views with respect to future events and financial performance and are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Such statements involve risks and uncertainties, which may cause actual results to differ materially from those set forth in these statements. For example, our forward-looking statements could be affected by risks that the acquisitions of the Hong Kong and Singapore operations of Royal & Sun Alliance Insurance plc (“RSA”) disrupt our current plans and operations; the ability to retain key personnel; the ability to recognize the benefits of the RSA acquisitions; the amount of costs, fees, expenses and charges related to the RSA acquisitions; pricing and policy term trends; increased competition; the adequacy of our loss reserves; negative rating agency actions; greater frequency or severity of unpredictable catastrophic events; the impact of acts of terrorism and acts of war; the company or its subsidiaries becoming subject to significant income taxes in the United States or elsewhere; changes in regulations or tax laws; changes in the availability, cost or quality of reinsurance or retrocessional coverage; adverse general economic conditions; and judicial, legislative, political and other governmental developments, as well as management’s response to these factors, and other factors identified in our filings with the U.S. Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date on which they are made. We are under no obligation (and expressly disclaim any such obligation) to update or revise any forward-looking statement that may be made from time to time, whether as a result of new information, future developments or otherwise. 2

Agenda  Executive Summary  Operating Segments  North American Insurance  Global Markets Insurance  Reinsurance  Financial Highlights  Conclusion  Appendix

General Casualty 22% Professional Liability 15% Healthcare 9% Specialty Reinsurance 7% Property Reinsurance 15% General Property 8% Other 12% Programs 4% (1) Allied World – A Niche Mix of Specialty Lines 4 Niche specialty insurance and reinsurance products offered across a global platform with operations in the United States, Bermuda, Canada, Lloyd’s, Europe, Hong Kong, Singapore and Australia Emphasis on insurance and casualty lines with opportunistic reinsurance and property capabilities Customer focus o Moving closer to clients o Demonstrated expertise in markets in which we underwrite o A “go to” market for targeted lines and industry verticals such as healthcare and real estate/construction 74% Casualty / 26% Property Total TTM March 2015 GPW: $2,915M We are a leading specialist insurance company with a broad range of product offerings, global capabilities and significant U.S. focus (1) Other includes the followings lines: general aviation, marine cargo, trade credit, North American M&A, primary construction, surety, energy, environmental and inland marine. Insurance 70% Reinsurance 30%

Experienced Management: Shifting the Business Focus 5 Since 2007, Allied World has built out a full U.S. specialty franchise, and more recently, has focused on developing its Global Markets Insurance 2007 GPW: $1,506M Total TTM March 2015 GPW: $2,915M Allied World 2007 Build out via expansion in Europe and Asia, including the launch of Syndicate 2232 at Lloyd’s, and the acquisitions of RSA’s Hong Kong and Singapore operations, which are expected to add ~$250M of additional annual premiums Post the 2008 Darwin acquisition, the North American Insurance segment has increased significantly with focus on small and middle market account primary and specialty business Reinsurance segment is flexible, with a strong U.S. and international presence Allied World TODAY Global Markets Insurance 17% North American Insurance 48% Reinsurance 30% North American Insurance 60% (1) 2008 Darwin GPW of $301M. Reinsurance 35% Gross premiums written have largely doubled over eight years, representing a CAGR of 10%

Allied World’s Evolution Allied World Zug office opens Build out of additional North American Insurance lines, including Defense Base Act, Surety, Construction, and Environmental, as well as Crop Reinsurance Build out of European platform including Aviation, Marine, Onshore Construction and Primary Casualty Launched a direct and facultative insurance business in Miami (1) In the fourth quarter of 2012, Allied World Financial Services entered into four strategic partnerships with Cunningham Lindsey, MatlinPatterson, Aeolus Capital Management and Crescent Capital Group. 6 2 0 0 8 2 0 0 9 2 0 1 0 2 0 1 1 2 0 1 2 2 0 1 3 2 0 1 4 2 0 1 5 Significant milestones achieved over the past seven years have shaped a global franchise

Strategy of Hiring Focused, Experienced Leadership 7 Targeted growth driven by key teams with seasoned experience and a shared culture Year Added Underwriting Team Senior Underwriters Average Years Industry Experience Selected Former Experience 2009 Defense Base Act 7 20 AIG, ACE 2011 Crop Reinsurance 1 28 Platinum 2011 Inland Marine 8 15 Axis, OneBeacon 2012 Construction 2 14 AIG, Markel 2012 Environmental 7 12 AIG, Tokio Marine 2012 U.S. M&A 4 12 AIG, Gulf, Banking/Finance/Legal Roles 2013 Aviation 3 15 Alterra/Markel 2013 Marine 3 21 Alterra, CV Starr, AIG, RSA 2013 Primary Casualty 3 37 XL Insurance, HCC 2013 Surety 7 10 AIG, American Safety, International Fidelity 2014 Architects & Engineers 2 35 AIG 2014 Onshore Construction 5 21 AIG, Munich Re, Tokio Marine, RSA 2014 Property Energy 2 35 Arch (1) (1) Senior underwriters are Assistant Vice President level and above; (2) Construction (North America); (3) Marine consists of Marine Cargo and Marine Liability; (4) North America Architects & Engineers; (5) Onshore Construction (Global Markets); (6) Canada Property Energy. (2) (3) (4) (5) (6)

0.3% 7.7% 6.1% 2.0% 5.5% 2.6% 3.1% 1.2% 1.0% 4.8% 4.2% 3.3% 2.5% 2.1% 1.9% 2.1% 2.3% 2.1% 2008 2009 2010 2011 2012 2013 2014 Q1 2014 Q1 2015 Total Return Annualized Book yield Investment Strategy 8 o Focus on total investment return as a key driver of book value growth; net investment income is one component o All investments categorized as “trading”, with mark-to- market flowing through income statement o Similar treatment of cash and derivatives o Senior management incentive compensation includes a focus on net income o Emphasis on detailed transparency o Maintain a short duration, overweight credit position in core fixed income o Continue to build out the non-core portfolio including equity investments via Allied World Financial Services (1) Prior to the 2009 move from an “available for sale” portfolio to a trading portfolio, which impacts the presentation of returns from the non-core portfolio. Total Investment Return ($MM) and Total Investment Portfolio ($BN) Book Yield vs. Total Return Focused on maximizing total return performance via a diversified portfolio (1) (1) $309 $301 $244 $196 $167 $158 $177 $48 $45 ($273) $77 $286 $10 $306 $59 $89 $54 $45 ($16) $179 ($61) ($46) ($18) Net investment income Realized gains (losses) Change in unrealized gains (losses) $20 $557 $469 $160 $455 $217 $6.9 $7.5 $8.0 $8.1 $8.8 $8.4 $8.5 $8.5 $8.6 $266 2008 2009 2010 2011 2012 2013 2014 Q1 2014 Q1 2015 $102 $90

$2,417 $3,213 $3,075 $3,149 $3,326 $3,520 $3,778 $3,829 $499 $499 $798 $798 $798 $798 $818 $819 -$646 -$682 -$1,475 -$1,658 -$1,975 -$2,197 -$2,449 -$2,708 $2,916 $3,712 $3,873 $3,947 $4,124 $4,318 $4,596 $4,648 $15.35 $19.85 $24.76 $26.70 $30.86 $34.20 $38.27 $38.99 2008 2009 2010 2011 2012 2013 2014 Q1 2015 Accumulated Share and Warrant Repurchases & Dividends Debt Shareholders' Equity Diluted Book Value per Share Active Capital Management Improves Shareholder Value 9 Capital Management History Share Repurchases: o Over $2.2(3) billion of shares and warrants repurchased since December 2007 o Approximately $175 million of remaining authorization in share repurchase program as of May 2015; plan expiring in May 2016 Dividends: o Increased the dividend 15% in April 2015 to $1.04 per share after an annual dividend increase of 35% and 33% in 2014 and 2013, respectively o Over $430(2) million of common dividends paid since going public in 2006 Conservative Capital Position: o Financial leverage of 17.6% at March 2015 (In millions, except for per share amounts) (1) Excludes $243.8 million syndicated loan that was repaid on February 23, 2009. (2) Includes dividends paid in April 2015. (3) Includes shares repurchased from Exor S.A. in May 2015. (1) (2,3) Diluted book value per share has more than doubled since 2008

39.3% 40.2% 43.5% 48.0% 51.2% 58.6% 64.5% 65.9% 69.7% 72.6% 80.3% 88.2% 90.5% 104.1% Allied World RLI W.R. Berkley Markel XL Arch ProAssurance Axis HCC Endurance Aspen Navigators Hanover Argo Superior Value Creation 10 Growth in book value per share calculated by taking change in book value per share from March 31, 2010 through March 31, 2015 adjusted for regular and special dividends. Diluted book value per share used when available; financial data is as of March 31, 2015. (1) Includes dividend of $0.225 per share declared in Q1 2015. Source: SNL Financial, Company filings. Peer Average = 62.5% Allied World CAGR = 15.3% (1) Five Year Growth in Book Value per Share April 2010 – March 2015

Agenda  Executive Summary  Operating Segments  North American Insurance  Global Markets Insurance  Reinsurance  Financial Highlights  Conclusion  Appendix

North American Insurance Segment 12 Specialty franchise with niche product offerings and expertise across primary and excess lines Healthcare 13% Inland Marine 4% Primary General Casualty 14% Programs 7% D&O Private 3% D&O Public 9% E&O 9% Environmental 4% Excess General Casualty 19% M&A 5% General Property 11% Property and casualty insurance for small and middle-market and Fortune 1000 companies through 13 offices in North America: o Fortune 1000-focused Bermuda platform is the largest direct business in Bermuda o Branch office network across the U.S. and Canada brings increased access to low limit accounts Industry verticals strategy: o Focused on servicing products in select specialty industry classes, including healthcare, private/non-profit, and public entity/construction Specialty product capabilities Admitted and excess & surplus lines (E&S) capabilities in all 50 states Total TTM March 2015 GPW: $1,751M Primary Construction 2%

Global Markets Insurance Segment 13 A targeted global presence poised for further growth Focused European and Lloyd’s expansion has driven growth Lloyd’s Syndicate 2232: o Launched own Managing Agency at Lloyd’s in April 2014 o Increased capacity and new lines added Specialty product capabilities: o Recent entry into aviation, marine cargo and liability, onshore construction and primary casualty RSA Hong Kong and Singapore: o Will materially increase Allied World’s Asian platform by providing access to attractive business and distribution o Acquisitions completed on April 1, 2015 General Casualty 14% Professional Lines 32% Aviation 13% Marine 6% General Property 13% SME 5% Trade Credit 11% Total TTM March 2015 GPW: $283M (1) SME: Small to medium enterprise. Healthcare 6% (1)

Reinsurance Segment 14 Flexibility to take advantage of opportunities as they arise Total TTM March 2015 GPW: $881M Global CAT 15% Global Property 5% North American Property 11% North American General Casualty 14% Global Casualty 7% Specialty 4% Crop 11% North American CAT 20% Professional Liability 7% • Opportunistic positioning and ability to size up or down with market conditions o Strategic partnership with Aeolus Capital Management • U.S. operation has access to U.S. regional business and strong local relationships o Property reinsurance capabilities that focus on small and medium account regional carriers • Strategic Bermuda platform o Property catastrophe, property per risk, workers’ compensation catastrophe, accident & health and specialty casualty • Miami, Singapore and Swiss offices and Lloyd’s Syndicate 2232 increase global reach and drive targeted growth Global Marine & Aerospace 6%

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Agenda  Executive Summary  Operating Segments  North American Insurance  Global Markets Insurance  Reinsurance  Financial Highlights  Conclusion  Appendix

Operating Results 2011 2012 2013 2014 Q1 2014 Q1 2015 Underwriting Income $59 $97 $278 $323 $107 $68 Operating Income $184 $203 $364 $415 $130 $92 Net Income $275 $493 $418 $490 $177 $124 Operating Return on Average Equity 6.0% 6.3% 10.6% 11.4% 14.6% 9.6% Net Income Return on Average Equity 8.9% 15.3% 12.2% 13.4% 19.8% 13.1% Combined Ratio 95.9% 94.5% 86.2% 85.2% 79.9% 88.1% Cash Flow from Operations $548 $629 $114 $417 $303 $318 Total Financial Statement Portfolio Return 2.0% 5.5% 2.6% 3.1% 1.2% 1.0% Ending Diluted Book Value per Share $26.70 $30.86 $34.20 $38.27 $35.68 $38.99 Growth in Diluted Book Value per Share 7.8% 15.6% 10.8% 11.9% 4.4% 1.9% Financial Highlights 17 Allied World has reported consistently strong results despite a competitive landscape, financial turbulence and catastrophe activity ($ in millions, except per share amounts)

22.5% 26.7% 30.2% 32.8% 30.1% 29.4% 30.2% 30.3% 30.9% 30.1% 30.5% 32.2% 33.3% 33.3% 33.8% 33.9% 35.0% 35.3% 2007 2008 2009 2010 2011 2012 2013 2014 Q1 2015 Allied World Peer Average Expense Ratio Advantage 18 Note: GAAP expense ratio; financial data is as of March 31, 2015. (1) Peer average includes ACGL, AGII, AHL, AXS, ENH, HCC, MKL, NAVG, PRA, RLI, THG, WRB, and XL. (2) April 1, 2015 close. Source: SNL Financial, Company filings. A 4.4 point advantage compared to peers (1) Our competitive expense ratio has been maintained over the course of the build-out of the U.S. and European platforms, the launch of Lloyd's Syndicate 2232, and the acquisitions of RSA’s Hong Kong and Singapore operations(2)

Growth Balanced with Underwriting Profitability 19 Consistent performance despite strong topline growth and a presence in varied lines of business Five Year Performance Average Combined Ratio vs. Growth in Net Premiums Earned ProAssurance not shown on chart (five year average combined ratio of 67.3% with net premium earned five-year CAGR of 5.1%). Financial data is as of March 31, 2015. Source: SNL Financial, Company filings. Allied World Arch Argo Aspen Axis Endurance Hanover HCC Markel Navigators XL RLI W.R. Berkley (5%) 0% 5% 10% 15% 20% 80% 85% 90% 95% 100% 105% N e t P re m iu ms Ea rn e d F iv e -y e ar C A G R 5 Year Average Combined Ratio

AY 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY Total CY Original Loss Ratio 70.1% 65.3% 75.9% 103.1% 59.6% 58.4% 55.6% 45.9% 52.0% 65.8% 65.1% 56.0% 54.9% 57.2% Prior Year Development 0.0% -4.9% -5.8% -3.6% -8.2% -10.2% -24.2% -18.8% -23.0% -17.4% -9.7% -9.0% -9.7% -11.2% AY Original Loss Ratio 70.1% 70.1% 81.7% 106.7% 67.7% 68.6% 79.8% 64.7% 75.1% 83.2% 74.9% 65.0% 64.7% 68.4% 2002 2003 ($57) ($57) 2004 (27) (53) (79) 2005 (8) (46) 6 (49) 2006 (16) (43) (45) (8) (113) 2007 6 (34) (77) (6) (26) (137) 2008 (9) (88) (100) (74) (8) (34) (313) 2009 (17) (57) (118) (103) 12 2 32 (248) 2010 4 (11) (57) (147) (54) (25) (23) (1) (313) 2011 (0) (1) (22) (90) (42) (69) (22) (28) 20 (254) 2012 4 (4) (9) (11) (82) (91) (35) (8) 11 53 (170) 2013 15 (3) (12) (14) (25) (48) (52) (26) (38) 7 16 (180) 2014 5 (2) (6) 12 (25) (39) (10) (69) (44) (7) 18 (45) ($213) 2015 (0) (1) (3) (3) (2) (8) 7 (28) (23) (6) 15 (3) (7) (64) Subsequent Development (99) (342) (444) (443) (253) (311) (103) (161) (74) 47 49 (49) (7) ($2,189) Loss Ratio Points -22.9% -29.2% -32.4% -32.6% -18.2% -23.2% -8.0% -12.2% -5.4% 3.2% 2.8% -2.4% -0.3% AY Developed 47.2% 40.9% 49.3% 74.1% 49.5% 45.4% 71.9% 52.5% 69.6% 86.5% 77.7% 62.6% 64.4% 68.4% Cat Losses 16.3% 28.0% 9.2% 5.9% 18.1% 9.9% 0.7% 3.0% AY Developed Excl. Cat Losses 47.2% 40.9% 33.0% 46.1% 49.5% 45.4% 62.7% 52.5% 63.7% 68.4% 67.8% 61.9% 61.4% 68.4% Case Incurred through 2015 Q1 45.1% 36.2% 47.6% 63.2% 40.5% 42.9% 59.4% 37.9% 56.1% 58.5% 52.5% 31.1% 21.6% 6.9% Remaining IBNR / EP Ratio @ 2015 Q1 2.0% 4.8% 1.7% 10.9% 9.0% 2.5% 12.5% 14.6% 13.5% 28.0% 25.1% 31.5% 42.7% 61.5% Strong Underwriting Results Since Inception 20 Historical Loss Ratios Through March 2015 ($MM) (2) (1) Pro-forma including Darwin development since inception. (2) Case incurred loss ratios by year are not directly comparable to our financial statements as reinsurance case incurred losses shown above are on a treaty year basis. (1)

Prudent Reserving Philosophy 21 $113 $137 $313 $248 $313 $254 $170 $180 $213 $49 $64 2006 2007 2008 2009 2010 2011 2012 2013 2014 Q1 2014 Q1 2015 o Net reserves approximately 4.2% above mid-point of range at March 31, 2015 o Over $2.1 billion net favorable reserve development since inception o 74% of net reserves are IBNR Net Prior Year Reserve Releases(1) ($MM) (1) Pro-forma including Darwin development since inception. March 31, 2015 Total: $4.5B Net Loss & LAE Reserve Mix at March 31, 2015 Case North American Insurance 15% IBNR Global Markets Insurance 7% Case Global Markets Insurance 2% IBNR Reinsurance 24% Case Reinsurance 9% IBNR North American Insurance 43%

Below Investment Grade Credit 4.1% Below Investment Grade Securitized 4.5% Equities 9.9% Hedge Funds 4.6% Private Equity Funds 4.2% Other Private Securities (AWFS) 1.6% Investment Portfolio Breakout 22 Core Assets 71.1% Non-Core Assets 28.9% Total Investment Portfolio at March 31, 2015: $8,637M Core assets include: cash and cash equivalents (6.5%), U.S. government securities (17.0%), U.S. government agencies (1.3%), non-U.S. government securities (2.2%), state, municipalities and political subdivisions (1.5%), mortgage-backed securities (11.3%), investment grade corporate securities (23.2%), and investment grade asset-backed securities (8.1%).

1.7% 1.4% 1.1% 1.1% 1.1% 1.0% 1.0% 1.0% 1.0% 0.9% 0.9% 0.7% 0.6% 0.5% MKL THG ACGL AHL PRA AWH WRB HCC RLI ENH NAVG AXS AGII XL 6.7% 5.4% 2.9% 4.1% -0.1% 1.7% 0.7% 0.4% 1.0% 0.7% -0.9% 1.4% 2.7% 1.4% 0.5% 0.6% 7.7% 6.1% 2.0% 5.5% 2.6% 3.1% 1.2% 1.0% 2009 2010 2011 2012 2013 2014 Q1 2014 Q1 2015Return from Non-Core Strategy Return from Fixed Income Strategy Customized Benchmark Investment Portfolio Return and Peer Comparison 23 • Portfolio was > 95% core fixed income in 2008 and has moved to a 71/29% core/non-core split at present • Returns from the non-core piece have generally had a disproportionately positive impact on the total investment return Composition of Allied World Total Investment Return March 31, 2015 Total Return(2) Financial data as of March 31, 2015. (1) Blend of Barclays Aggregate benchmarks representative of the underlying sectors of our portfolio. (2) Source: Company filings. Peer Average = 1.0% (1) We have increased our allocation to investment strategies outside of the core fixed income portfolio

4.1% 5.2% 6.1% 6.2% 7.3% 7.6% 7.9% 10.5% 10.8% 11.9% 12.0% 13.1% 13.8% 14.8% Arch W.R. Berkley Allied World ProAssurance RLI XL Argo Hanover Markel Navigators Aspen Endurance HCC Axis Peer Comparisons – Net Income ROE 24 Financial data is as of March 31, 2015. Source: SNL Financial, Company filings. Peer Average = 9.0% Five Year Average Quarterly Annualized Net Income ROE April 2010 – March 2015

Agenda  Executive Summary  Operating Segments  North American Insurance  Global Markets Insurance  Reinsurance  Financial Highlights  Conclusion  Appendix

Conclusion 26 Allied World is attractively valued given its demonstrated ability to grow book value Five Year Growth in Book Value per Share (through March 2015) vs. Price to Book Value @ May 7, 2015 Growth in book value per share calculated by taking change in diluted book value per share from March 31, 2010 through March 31, 2015 adjusted for dividends. Diluted book value per share used when available; RLI not shown on chart (five year growth in book value per share of 80% with price to book value of 2.49x as of May 7, 2015). Financial data is as of Q1 2015; trading data is as of May 7, 2015. (1)Includes dividend of $0.225 per share declared in Q1 2015. (1) Allied World Arch Argo Aspen Axis Endurance Hanover HCC Markel Navigators XL ProAssurance W.R. Berkley 0.7x 0.9x 1.1x 1.3x 1.5x 30% 45% 60% 75% 90% 105% 120% P ri ce t o D ilu te d B o o k V al u e P e r Sh ar e Five Year Growth in Diluted Book Value Per Share

Conclusion 27 Allied World has generated sector leading total value creation Five Year Value Creation CAGR vs. Total Stock Return CAGR Five year value creation calculated by taking the change in diluted book value per share from March 31, 2010 through March 31, 2015 adjusted for dividends. Diluted book value per share used when available. Total stock return calculated by taking the change in end-of-day stock price from April 1, 2010 through March 31, 2015 adjusted for dividends; financial data is as of Q1 2015. (1 Includes dividend of $0.225 per share declared in Q1 2015. (1) Allied World RLI Arch W.R. Berkley Aspen Axis Endurance Hanover HCC Navigators ProAssurance Argo Markel XL 10.0% 15.0% 20.0% 25.0% 6% 8% 10% 12% 14% 16% To ta l S to ck R e tu rn C A G R Five Year Value Creation CAGR R2 = 0.59

Agenda  Executive Summary  Operating Segments  North American Insurance  Global Markets Insurance  Reinsurance  Financial Highlights  Conclusion  Appendix

Non-GAAP Financial Measures In presenting the company's results, management has included and discussed in this presentation certain non generally accepted accounting principles ("non- GAAP") financial measures within the meaning of Regulation G as promulgated by the U.S. Securities and Exchange Commission. Management believes that these non-GAAP measures, which may be defined differently by other companies, better explain the company's results of operations in a manner that allows for a more complete understanding of the underlying trends in the company's business. However, these measures should not be viewed as a substitute for those determined in accordance with generally accepted accounting principles ("U.S. GAAP"). "Operating income" is an internal performance measure used in the management of the company’s operations and represents after-tax operational results excluding, as applicable, net realized investment gains or losses, net impairment charges recognized in earnings, net foreign exchange gain or loss and other non- recurring items. The company excludes net realized investment gains or losses, net impairment charges recognized in earnings, net foreign exchange gain or loss, and other non-recurring items from the calculation of operating income because these amounts are heavily influenced by and fluctuate in part according to the availability of market opportunities and other factors. The company has excluded from operating income the termination fee received from Transatlantic Holdings, Inc. in 2011 as this is a non-recurring item. In addition to presenting net income determined in accordance with U.S. GAAP, the company believes that showing operating income enables investors, analysts, rating agencies and other users of the company’s financial information to more easily analyze our results of operations and underlying business performance. Operating income should not be viewed as a substitute for U.S. GAAP net income. The company has included "diluted book value per share" because it takes into account the effect of dilutive securities; therefore, the company believes it is an important measure of calculating shareholder returns. "Annualized net income return on average shareholders' equity" ("ROAE") is calculated using average shareholders’ equity, excluding the average after tax unrealized gains (or losses) on investments. Unrealized gains (losses) on investments are primarily the result of interest rate and credit spread movements and the resultant impact on fixed income securities. Such gains (losses) are not related to management actions or operational performance, nor are they likely to be realized. Therefore, the company believes that excluding these unrealized gains (losses) provides a more consistent and useful measurement of operating performance, which supplements U.S. GAAP information. In calculating ROAE, the net income (loss) available to shareholders for the period is multiplied by the number of such periods in a calendar year in order to arrive at annualized net income (loss) available to shareholders. The company presents ROAE as a measure that is commonly recognized as a standard of performance by investors, analysts, rating agencies and other users of its financial information. "Annualized operating return on average shareholders' equity" is calculated using operating income (as defined above and annualized in the manner described for net income (loss) available to shareholders under ROAE above), and average shareholders' equity, excluding the average after tax unrealized gains (losses) on investments. Unrealized gains (losses) are excluded from equity for the reasons outlined in the annualized net income return on average shareholders' equity explanation above. See slides 30 – 32 for a reconciliation of non-GAAP measures used in this presentation to their most directly comparable U.S. GAAP measures. 29

Non-GAAP Financial Measures - Reconciliations 30 ALLIED WORLD ASSURANCE COMPANY HOLDINGS, AG UNAUDITED OPERATING INCOME RECONCILIATION (Expressed in thousands of United States dollars, except share and per share amounts) Three Months Ended March 31, 2015 2014 Net income $ 124,356 $ 176,972 Add after tax effect of: Net realized investment gains (42,572) (47,164) Foreign exchange loss 9,897 49 Operating income $ 91,681 $ 129,857 Weighted average common shares outstanding: Basic 95,935,551 99,545,187 Diluted 97,577,029 101,584,662 Basic per share data: Net income $ 1.30 $ 1.78 Add after tax effect of: Net realized investment gains (0.44) (0.47) Foreign exchange loss 0.10 0.00 Operating income $ 0.96 $ 1.31 Diluted per share data: Net income $ 1.27 $ 1.74 Add after tax effect of: Net realized investment gains (0.44) (0.46) Foreign exchange loss 0.10 0.00 Operating income $ 0.93 $ 1.28

Non-GAAP Financial Measures - Reconciliations 31 ALLIED WORLD ASSURANCE COMPANY HOLDINGS, AG UNAUDITED ANNUALIZED RETURN ON SHAREHOLDERS' EQUITY RECONCILIATION (Expressed in thousands of United States dollars, except for percentage information) Three Months Ended March 31, 2015 2014 Opening shareholders' equity $ 3,778,291 $ 3,519,826 Deduct: accumulated other comprehensive income — — Adjusted opening shareholders' equity 3,778,291 3,519,826 Closing shareholders' equity $ 3,829,067 $ 3,616,678 Deduct: accumulated other comprehensive income — — Adjusted closing shareholders' equity 3,829,067 3,616,678 Average shareholders' equity $ 3,803,679 $ 3,568.252 Net income available to shareholders $ 124,356 $ 176,972 Annualized net income available to shareholders 497,424 707,888 Annualized return on average shareholders' equity - net income av ilable to shareholders 13.1 % 19.8 % Operating income available to shareholders $ 91,681 $ 129,857 Annualized operating income available to shareholders 366,724 519,428 Annualized return on average shareholders' equity - operating income available to shareholders 9.6 % 14.6 %

Non-GAAP Financial Measures - Reconciliations 32 ALLIED WORLD ASSURANCE COMPANY HOLDINGS, AG UNAUDITED DILUTED BOOK VALUE PER SHARE RECONCILIATION (Expressed in thousands of United States dollars, except share and per share amounts) As of As of March 31, December 31, 2015 2014 Price per share at period end $ 40.40 $ 37.92 Total shareholders' equity $ 3,829,067 $ 3,778,291 Basic common shares outstanding 95,444,669 96,195,482 Add: unvested restricted share units 843,607 502,506 Add: performance based equity awards 596,224 616,641 Add: employee share purchase plan 30,504 42,176 Add: dilutive options outstanding 2,212,247 2,426,674 Weighted average exercise price per share $ 16.73 $ 16.41 Deduct: options bought back via treasury method (916,111) (1,050,151) Common shares and common share equivalents outstanding 98,211,140 98,733,328 Basic book value per common share $ 40.12 $ 39.28 Diluted book value per common share $ 38.99 $ 38.27