NEW YORK (Standard&Poor's CreditWire) June 7, 2001--Standard&Poor's today assigned its triple-'B'-minus senior debt rating to Markel Corp.'s (Markel) $100 million zero-coupon convertible debt issue. At the same time, Standard&Poor's affirmed various ratings on Markel and related entities (see list). The outlook remains negative. The debt issue represents a drawdown on Markel's $475 million shelf registration, which was filed in January 2001. Standard&Poor's expects financial leverage at the holding company to remain unchanged from current levels, as proceeds from the debt offering are expected to be used to replace existing debt. The current ratings reflect Markel's lower-than-historical (albeit improving) operating earnings and fixed-charge coverageas well as its adequate capitalization. Partially offsetting these concerns