TABLE OF CONTENTS
Section 7 — Regulation FD
Item 7.01 Regulation FD Disclosure
Following the publication of Aspen Insurance Holdings Limited’s (the “Company” or “Aspen”)
earnings release and financial supplement on October 29, 2008, the impairment charge for the
quarter and nine months ended September 30, 2008 increased from the reported $44.5 million to $55.8
million due to the sale of certain bonds in financial institutions after the quarter-end. Where we
assess unrealized losses on securities to be temporary at the balance sheet date, we incur no
impairment charge, as we maintain the ability and intent to hold these securities until their
market values recover to amortized cost.
Subsequent to September 30, 2008, we sold a portion of our holdings in the bonds of certain
financial institutions, receiving $87.5 million in proceeds from the sales. As at September 30,
2008 we recognized impairment charges on these holdings of $11.3 million, based on their value at
that date. As the fair value of these bonds appreciated between September 30, 2008, and the dates
of their disposal, we will recognize a realized gain of $6.7 million, pre-tax, in the fourth
quarter of 2008, in relation to such holdings and in accordance with the current accounting
standards. This reflects the reversal of a portion of the $11.3 million impairment charge
accounted for at September 30, 2008.
Attached as Exhibit 99.1 is an updated earnings release supplement for the period ended
September 30, 2008, reflecting the above-mentioned adjustments.
In addition, the information about the Company described in the slides attached to this report
as Exhibit 99.2 will be presented by the Chief Executive Officer and Chief Financial Officer of the
Company to various investors starting November 11, 2008 and throughout the months of November and
December. The Company furnishes the attached presentation which includes general information about
the Company, its diversification and its impact on performance, current performance and outlook,
2008 third quarter and nine months results, current market rates and conditions and 2008 Guidance
as at the Company’s earnings call on October 30, 2008. The attached slides also update the
earnings slide presentation filed with the SEC on October 31, 2008 to reflect the above-mentioned
adjustments.
Safe Harbor for Forward-Looking Statements
Some of the statements in Exhibit 99.1 include forward-looking statements which reflect our current
views with respect to future events and financial performance. Such statements may include
forward-looking statements both with respect to us in general and the insurance and reinsurance
sectors specifically, both as to underwriting and investment matters. Statements that include the
words “expect,” “intend,” “plan,” “believe,” “project,” “anticipate,” “seek,” “will,” “estimate,”
“aim,” “may,” “guidance,” “continue,” and similar statements of a future or forward-looking nature
identify forward-looking statements in Exhibit 99.2 for purposes of the U.S. federal securities
laws or otherwise. We intend these forward-looking statements to be covered by the safe harbor
provisions for forward-looking statements in the Private Securities Litigation Reform Act of 1995.
All forward-looking statements address matters that involve risks and uncertainties. Accordingly,
there are or may be important factors that could cause actual results to differ from those
indicated in the forward-looking statements. See slide 2 of the attached presentation on Exhibit
99.2 for such factors as well as our Annual Report on Form 10-K filed with the SEC.
Forward-looking statements speak only as of the date on which they are made, and we undertake no
obligation publicly to update or revise any forward-looking statement, whether as a result of new
information, future developments or otherwise.
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