Strong competitive position in excess and surplus lines of business. Significant deleveraging of balance sheet. Concerns about performance of 2008 and 2009 accident years, due to market deterioration. Potential for adverse reserve development on legacy reserves. Significant investment risk, albeit reduced from historical levels. The unsolicited counterparty credit rating on Markel Corp. (NYSE: MKL) is based on the company's strong competitive position in the excess and surplus (E&S) market and the significant deleveraging of its balance sheet. These strengths are partially offset by the deteriorating market conditions' effect on its operating performance, the potential for adverse reserve development on legacy reserves, and significant investment risk, albeit reduced from historical levels. Markel has a strong competitive position in the E&S market
