Table of Contents RESERVES - ESTIMATES AND UNCERTAINTIES Property and Casualty Claim and Claim Adjustment Expense Reserves The level of reserves we maintain represents our best estimate, as of a particular point in time, of what the ultimate settlement and administration of claims will cost based on our assessment of facts and circumstances known at that time. Reserves are not an exact calculation of liability but instead are complex estimates that we derive, generally utilizing a variety of actuarial reserve estimation techniques, from numerous assumptions and expectations about future events, both internal and external, many of which are highly uncertain. As noted below, we review our reserves for each segment of our business periodically, and any such review could result in the need to increase reserves in amounts which could be material and could adversely affect our results of operations, equity, business and insurer financial strength and corporate debt ratings. Further information on reserves is provided in Note E to the Consolidated Financial Statements included under Item 8. We maintain loss reserves to cover our estimated ultimate unpaid liability for claim and claim adjustment expenses, including the estimated cost of the claims adjudication process, for claims that have been reported but not yet settled (case reserves) and claims that have been incurred but not reported (IBNR). IBNR includes a provision for development on known cases as well as a provision for late reported incurred claims. Claim and claim adjustment expense reserves are reflected as liabilities and are included on the Consolidated Balance Sheets under the heading “Insurance Reserves.” Adjustments to prior year reserve estimates, if necessary, are reflected in results of operations in the period that the need for such adjustments is determined. The carried case and IBNR reserves as of each balance sheet date are provided in the Segment Results section of this MD&A and in Note E to the Consolidated Financial Statements included under Item 8. As discussed in the Risk Factors discussion within Item 1A, there is a risk that our recorded reserves are insufficient to cover our estimated ultimate unpaid liability for claims and claim adjustment expenses. Unforeseen emerging or potential claims and coverage issues are difficult to predict and could materially adversely affect the adequacy of our claim and claim adjustment expense reserves and could lead to future reserve additions. In addition, our property and casualty insurance subsidiaries also have actual and potential exposures related to A&EP claims, which could result in material losses. To mitigate the risks posed by our exposure to A&EP claims and claim adjustment expenses, we completed a transaction with NICO under which substantially all of our legacy A&EP liabilities were ceded to NICO effective January 1, 2010. See Note E to the Consolidated Financial Statements included under Item 8 for further discussion about the transaction with NICO, its impact on our results of operations and the deferred retroactive reinsurance gain. In developing claim and claim adjustment expense (“loss” or “losses”) reserve estimates, our actuaries perform detailed reserve analyses that are staggered throughout the year. The data is organized at a reserve group level. A reserve group can be a line of business covering a subset of insureds such as commercial automobile liability for small or middle market customers, it can encompass several lines of business provided to a specific set of customers such as aging services, or it can be a particular type of claim such as construction defect. Every reserve group is reviewed at least once during the year, but most are reviewed more frequently. The analyses generally review losses gross of ceded reinsurance and apply the ceded reinsurance terms to the gross estimates to establish estimates net of reinsurance. In addition to the detailed analyses, we review actual loss emergence for all products each quarter. Most of our business can be characterized as long-tail. For long-tail business, it will generally be several years between the time the business is written and the time when all claims are settled. Our long-tail exposures include commercial automobile liability, workers' compensation, general liability, medical professional liability, other professional liability and management liability coverages, assumed reinsurance run-off and products liability. Short-tail exposures include property, commercial automobile physical damage, marine, surety and warranty. Specialty, Commercial and International contain both long-tail and short-tail exposures. Corporate & Other contains run-off long-tail exposures. Various methods are used to project ultimate losses for both long-tail and short-tail exposures. Establishing Property & Casualty Reserve Estimates 20