The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE

OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8

COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
ALPHABET INC CAP STK CL C 02079K107 1,179 570 SH   DFND 1 0 570 0
ALPHABET INC CAP STK CL A 02079K305 1,444 700 SH   DFND 1 0 700 0
ALPHABET INC CAP STK CL A 02079K305 255,354 123,807 SH   DFND 1 0 123,807 0
ALPHABET INC CAP STK CL C 02079K107 177,437 85,775 SH   DFND 1 0 85,775 0
AMAZON COM INC COM 023135106 774 250 SH   DFND 1 0 250 0
BERKSHIRE HATHAWAY INC DEL CL A 084670108 115,711 300 SH   DFND 1 0 300 0
BERKSHIRE HATHAWAY INC DEL CL B NEW 084670702 8,119 31,780 SH   DFND 1 0 31,780 0
CREDIT ACCEP CORP MICH COM 225310101 68,444 190,000 SH   DFND 1 0 190,000 0
FACEBOOK INC CL A 30303M102 55,961 190,000 SH   DFND 1 0 190,000 0
INTERACTIVE BROKERS GROUP IN COM CL A 45841N107 1,612 22,074 SH   DFND 1 0 22,074 0
MARKEL CORP COM 570535104 2,650 2,325 SH   DFND 1 0 2,325 0
MERCADOLIBRE INC COM 58733R102 471 320 SH   DFND 1 0 320 0
MERCADOLIBRE INC COM 58733R102 1,619 1,100 SH   DFND 1 0 1,100 0
MICROSOFT CORP COM 594918104 182,368 773,500 SH   DFND 1 0 773,500 0
MICROSOFT CORP COM 594918104 2,358 10,000 SH   DFND 1 0 10,000 0
SALESFORCE COM INC COM 79466L302 31,781 150,000 SH   DFND 1 0 150,000 0
SLACK TECHNOLOGIES INC COM CL A 83088V102 31,691 780,000 SH   DFND 1 0 780,000 0
SLACK TECHNOLOGIES INC COM CL A 83088V102 6,095 150,000 SH   DFND 1 0 150,000 0
TUCOWS INC COM NEW 898697206 7,053 91,000 SH   DFND 1 0 91,000 0
TUCOWS INC COM NEW 898697206 7,410 95,612 SH   DFND 1 0 95,612 0
TUCOWS INC COM NEW 898697206 2,170 28,000 SH   DFND 1 0 28,000 0
TUCOWS INC COM NEW 898697206 108,006 1,393,627 SH   DFND 1 0 1,393,627 0
WABTEC CORP COM 929740108 919 11,612 SH   DFND 1 0 11,612 0
WIX COM LTD SHS M98068105 72,597 260,000 SH   DFND 1 0 260,000 0