Page 1

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 FORM 10 - Q × Quarterly report pursuant to Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 for the quarterly period ended March 31 , 2021 ☐ period from or Transition report pursuant to Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 for the transition to Commission File Number : 001-15811 MARKEL CORPORATION ( Exact name of registrant as specified in its charter ) Virginia ( State or other jurisdiction of incorporation or organization ) 54-1959284 ( I.R.S. Employer Identification No. ) 4521 Highwoods Parkway , Glen Allen , Virginia 23060-6148 ( Address of principal executive offices ) ( Zip Code ) ( 804 ) 747-0136 ( Registrant's telephone number , including area code ) Securities registered pursuant to Section 12 ( b ) of the Act : Title of each class Common Stock , no par value Trading Symbol ( s ) MKL Name of exchange on which registered New York Stock Exchange Indicate by check mark whether the registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes × No □ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T ( §232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes x No ☐ Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definitions of " large accelerated filer , " " accelerated filer , " " smaller reporting company , " and " emerging growth company " in Rule 12b - 2 of the Exchange Act . Large accelerated filer Smaller reporting company ☐ Accelerated filer Emerging growth company ☐ ☐ Non - accelerated filer If an emerging growth company , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Exchange Act ) . Yes ☐ No x Number of shares of the registrant's common stock outstanding at April 21 , 2021 : 13,758,155