NEW YORK (Standard & Poor's) Aug. 14, 2006--Standard & Poor's Ratings Services said today it assigned its 'BBB-' senior debt rating to Markel Corp.'s (Markel) proposed $100 million to $150 million callable senior debentures due 2046. At the same time, Standard & Poor's affirmed its 'BBB-' counterparty credit rating on Markel. The outlook remains stable. "The counterparty credit rating on Markel reflects its very strong competitive position and operating performance (excluding a large hurricane loss in third-quarter 2005) in some of its operating segments and its geographic diversification," explained Standard & Poor's credit analyst Jason Jones. Partially offsetting these strengths is the relatively weak performance in Markel's international operations, especially in the discontinued operations, the company's somewhat high financial leverage,