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 1,429 570 SH   DFND 1 0 570 0
ALPHABET INC CAP STK CL A 02079K305 1,709 700 SH   DFND 1 0 700 0
ALPHABET INC CAP STK CL A 02079K305 302,311 123,807 SH   DFND 1 0 123,807 0
ALPHABET INC CAP STK CL C 02079K107 214,980 85,775 SH   DFND 1 0 85,775 0
AMAZON COM INC COM 023135106 860 250 SH   DFND 1 0 250 0
BERKSHIRE HATHAWAY INC DEL CL A 084670108 125,580 300 SH   DFND 1 0 300 0
BERKSHIRE HATHAWAY INC DEL CL B NEW 084670702 8,832 31,780 SH   DFND 1 0 31,780 0
CREDIT ACCEP CORP MICH COM 225310101 86,281 190,000 SH   DFND 1 0 190,000 0
FACEBOOK INC CL A 30303M102 66,065 190,000 SH   DFND 1 0 190,000 0
INTERACTIVE BROKERS GROUP IN COM CL A 45841N107 1,780 27,074 SH   DFND 1 0 27,074 0
INTERACTIVE BROKERS GROUP IN COM CL A 45841N107 2,629 40,000 SH   DFND 1 0 40,000 0
MARKEL CORP COM 570535104 2,759 2,325 SH   DFND 1 0 2,325 0
MERCADOLIBRE INC COM 58733R102 1,402 900 SH   DFND 1 0 900 0
MERCADOLIBRE INC COM 58733R102 2,025 1,300 SH   DFND 1 0 1,300 0
MICROSOFT CORP COM 594918104 209,541 773,500 SH   DFND 1 0 773,500 0
MICROSOFT CORP COM 594918104 2,709 10,000 SH   DFND 1 0 10,000 0
SALESFORCE COM INC COM 79466L302 36,641 150,000 SH   DFND 1 0 150,000 0
SLACK TECHNOLOGIES INC COM CL A 83088V102 34,554 780,000 SH   DFND 1 0 780,000 0
TUCOWS INC COM NEW 898697206 7,309 91,000 SH   DFND 1 0 91,000 0
TUCOWS INC COM NEW 898697206 8,835 110,000 SH   DFND 1 0 110,000 0
TUCOWS INC COM NEW 898697206 2,490 31,000 SH   DFND 1 0 31,000 0
TUCOWS INC COM NEW 898697206 111,936 1,393,627 SH   DFND 1 0 1,393,627 0
WIX COM LTD SHS M98068105 75,473 260,000 SH   DFND 1 0 260,000 0