NEW YORK (Standard & Poor's) Feb. 26, 2003--Standard & Poor's Ratings Services said today that it assigned its 'BBB-' senior debt rating to Virginia-based Markel Corp.'s (Markel) $200 million 2003 Series A 6.80% senior notes due 2013. The notes issuance represents a drawdown on Markel's $475 million shelf registration, which was filed in January 2001. "The rating on the notes reflects Markel's strong business position in the specialty insurance market, good capital adequacy at the operating companies, and improved financial leverage over recent years," said Standard & Poor's credit analyst Laline Carvalho. Partially offsetting these factors is the group's poor consolidated operating performance in 2000 and 2001, following its acquisition of Markel International (formerly Terra Nova (Bermuda) Holdings Ltd.) in