SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-A FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES PURSUANT TO SECTION 12(b) OR 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934. Aspen Insurance Holdings Limited -------------------------------- (Exact Name of Registrant as Specified in Its Charter) Bermuda Not Applicable ------------------------------ ------------------- (Jurisdiction of Incorporation (IRS Employer or Organization) Identification No.) Victoria Hall 11 Victoria Street Hamilton HM 11 Bermuda (Address of Principal Executive Offices) If this form relates to the registration of a If this form relates to the registration of a class of securities pursuant to Section 12(b) class of securities pursuant to Section 12(g) of the Exchange Act and is effective of the Exchange Act and is effective pursuant to General Instruction A.(c), check pursuant to General Instruction A.(d), check the following box. [ x ] the following box. [ ] Securities Act registration statement file number to which this form relates: 333-110435 Securities to be registered pursuant to Section 12(b) of the Act: Name of Each Exchange on Which Each Title of Each Class to be so Registered Class is to be Registered - ------------------------------------------- ----------------------------------- Ordinary Shares, Par Value 0.15144558(cents) New York Stock Exchange per share (the "Ordinary Shares") Securities to be registered pursuant to Section 12(g) of the Act: None (Title of Class) ITEM 1. DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED A description of the Ordinary Shares to be registered hereunder is set forth under the captions "Description of Share Capital" and "Shares Eligible for Future Sale" in the registrant's registration statement on Form F-1, Registration No. 333-110435, filed with the Securities and Exchange Commission on November 12, 2003, and thereafter amended and supplemented (the "Registration Statement"), which description is hereby incorporated by reference. Any form of prospectus that constitutes part of the Registration Statement and is filed by the registrant pursuant to Rule 424(b) under the Securities Act of 1933, as amended, shall be deemed incorporated herein by reference. ITEM 2. EXHIBITS Not applicable. 2 SIGNATURE Pursuant to the requirements of Section 12 of the Securities Exchange Act of 1934, the Registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized. ASPEN INSURANCE HOLDINGS LIMITED By: /s/ Julian Cusack ------------------------ Julian Cusack Chief Financial Officer DATED: November 25, 2003 3