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 1, 2014

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, AG

(Exact Name of Registrant as Specified in Charter)

Lindenstrasse 8

6340 Baar

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:

Item 5.03.  Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.

Allied World Assurance Company Holdings, AG (the “Company”) held its 2014 Annual General Meeting of Shareholders on May 1, 2014 (the “2014 Annual Shareholder Meeting”). At the 2014 Annual Shareholder Meeting, the Company’s shareholders approved the proposals listed in Item 5.07. The amendments to the Company’s Articles of Association (the “Articles of Association”) to (1) elect annually (i) each director individually, (ii) the Chairman of the Company’s board of directors (the “Board”), (iii) the members of the Compensation Committee, and (iv) the independent proxy (Proposal 1); (2) effect a 3-for-1 split of the Company’s common shares (Proposal 12); and (3) extend the Board’s ability to issue authorized share capital until May 1, 2016 (Proposal 13) are effective immediately and are reflected in the Company’s amended and restated Articles of Association attached hereto as Exhibit 3.1 and incorporated herein by reference. The amendments to the Articles of Association to reduce the Company’s share capital through the cancellation of a portion of shares held in treasury (Proposal 10) will become effective upon the registration of such amendment with the Commercial Register in the Canton of Zug, Switzerland, at which time the Company will file amended and restated Articles of Association.

Item 5.07.  Submission of Matters to a Vote of Security Holders.

The Company’s shareholders considered the following proposals, each of which is described in greater detail in the Company’s definitive proxy statement dated March 14, 2014.

Proposal 1          Approval of Amendments to the Articles of Association for Annual Elections

The Company’s shareholders approved amendments to the Articles of Association to elect annually (i) each director individually, (ii) the Chairman of the Board, (iii) the members of the Compensation Committee and (iv) the independent proxy.

Proposal 2          Election of Directors

The Company’s shareholders elected the following directors to hold office until the Company’s Annual Shareholder Meeting in 2015:

Proposal 3          Election of Chairman of the Board

The Company’s shareholders elected Scott A. Carmilani as the Chairman of the Board to hold office until the Company’s Annual Shareholder Meeting in 2015.

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Proposal 4          Election of Compensation Committee Members

The Company’s shareholders elected the following directors as members of the Compensation Committee of the Board to serve until the Company’s Annual Shareholder Meeting in 2015:

Proposal 5          Election of the Independent Proxy

The Company’s shareholders elected Buis Buergi AG as the independent proxy to serve at and until the conclusion of the Company’s Annual Shareholder Meeting in 2015.

Proposal 6          Advisory Vote on Named Executive Officer Compensation

The Company’s shareholders approved an advisory vote on the Company’s named executive officer compensation.

Proposal 7          Approval of the Company’s Annual Report and Financial Statements

The Company’s shareholders approved the Company’s 2013 Annual Report and its consolidated financial statements and audited statutory financial statements for the year ended December 31, 2013.

Proposal 8          Approval of Retention of Disposable Profits

The Company’s shareholders approved the retention of disposable profits.

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Proposal 9          Approval of Dividend Payments

The Company’s shareholders approved the payment of dividends to the Company’s shareholders from general legal reserve from capital contributions.

Proposal 10          Approval of Cancellation of Treasury Shares

The Company’s shareholders approved an amendment to the Articles of Association to reduce the Company’s share capital through the cancellation of a portion of shares held in treasury.

Proposal 11          Approval of New Share Repurchase Program

The Company’s shareholders approved a new $500 million share repurchase program.

Proposal 12          Approval of 3-for-1 Split of Common Shares

The Company’s shareholders approved a 3-for-1 split of the Company’s common shares.

Proposal 13          Approval of Extension of Board’s Ability to Issue Authorized Share Capital

The Company’s shareholders approved an amendment to the Articles of Association to extend the Board’s ability to issue authorized share capital until May 1, 2016.

Proposal 14          Election of Auditors

The Company’s shareholders elected Deloitte & Touche Ltd. as the Company’s independent auditor and Deloitte AG as the Company’s statutory auditor, each to serve until the Company’s Annual Shareholder Meeting in 2015.

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Proposal 15          Election of Special Auditor

The Company’s shareholders elected PricewaterhouseCoopers AG as the Company’s special auditor to serve until the Company’s Annual Shareholder Meeting in 2015.

Proposal 16          Approval of Granting a Discharge

The Company’s shareholders approved a discharge to the Company’s Board and executive officers from liabilities for their actions during the year ended December 31, 2013.

Item 9.01.  Financial Statements and Exhibits.

(d)          Exhibits

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SIGNATURE

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.

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