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
58 COM INC SPON ADR REP A 31680Q104 146,959 5,248,519 SH   SOLE   5,248,519 0 0
AFFILIATED MANAGERS GROUP COM 008252108 2,419 16,645 SH   SOLE   16,645 0 0
ALIBABA GROUP HLDG LTD SPONSORED ADS 01609W102 293 3,335 SH   SOLE   3,335 0 0
ALIGN TECHNOLOGY INC COM 016255101 4,626 48,118 SH   SOLE   48,118 0 0
ALPHABET INC CAP STK CL A 02079K305 307,119 387,556 SH   SOLE   387,556 0 0
ALPHABET INC CAP STK CL C 02079K107 327,354 424,132 SH   SOLE   424,132 0 0
AMAZON COM INC COM 023135106 335,571 447,506 SH   SOLE   447,506 0 0
AMERICAN ELEC PWR INC COM 025537101 975 15,485 SH   SOLE   15,485 0 0
AMERICAN EXPRESS CO COM 025816109 49,818 672,484 SH   SOLE   672,484 0 0
ARCH CAP GROUP LTD ORD G0450A105 819 9,488 SH   SOLE   9,488 0 0
AT&T INC COM 00206R102 3,506 82,445 SH   SOLE   82,445 0 0
ATHENAHEALTH INC COM 04685W103 31,778 302,156 SH   SOLE   302,156 0 0
AUTOHOME INC SP ADR RP CL A 05278C107 1,268 50,167 SH   SOLE   50,167 0 0
BAIDU INC SPON ADR REP A 056752108 434,940 2,645,459 SH   SOLE   2,645,459 0 0
BERKSHIRE HATHAWAY INC DEL CL A 084670108 1,171,781 4,800 SH   SOLE   4,800 0 0
BERKSHIRE HATHAWAY INC DEL CL B NEW 084670702 644,836 3,956,534 SH   SOLE   3,956,534 0 0
BUILDERS FIRSTSOURCE INC COM 12008R107 54,931 5,007,377 SH   SOLE   5,007,377 0 0
CABLE ONE INC COM 12685J105 2,007 3,228 SH   SOLE   3,228 0 0
CAPITAL ONE FINL CORP COM 14040H105 104,688 1,200,000 SH   SOLE   1,200,000 0 0
CARMAX INC COM 143130102 647,271 10,052,354 SH   SOLE   10,052,354 0 0
CATERPILLAR INC DEL COM 149123101 635 6,848 SH   SOLE   6,848 0 0
CHARTER COMMUNICATIONS INC N CL A 16119P108 4,576 15,892 SH   SOLE   15,892 0 0
CHIPOTLE MEXICAN GRILL INC COM 169656105 203,614 539,633 SH   SOLE   539,633 0 0
COCA COLA CO COM 191216100 2,437 58,788 SH   SOLE   58,788 0 0
COSTCO WHSL CORP NEW COM 22160K105 70,474 440,162 SH   SOLE   440,162 0 0
CRESUD S A C I F Y A SPONSORED ADR 226406106 9,728 616,883 SH   SOLE   616,883 0 0
CVS HEALTH CORP COM 126650100 1,057 13,401 SH   SOLE   13,401 0 0
D R HORTON INC COM 23331A109 11,205 410,000 SH   SOLE   410,000 0 0
DANAHER CORP DEL COM 235851102 134,918 1,733,275 SH   SOLE   1,733,275 0 0
DENTSPLY SIRONA INC COM 24906P109 525,500 9,102,714 SH   SOLE   9,102,714 0 0
EDISON INTL COM 281020107 3,088 42,900 SH   SOLE   42,900 0 0
EMCOR GROUP INC COM 29084Q100 98,425 1,390,969 SH   SOLE   1,390,969 0 0
EXPEDITORS INTL WASH INC COM 302130109 423 7,978 SH   SOLE   7,978 0 0
EXXON MOBIL CORP COM 30231G102 4,080 45,201 SH   SOLE   45,201 0 0
FACEBOOK INC CL A 30303M102 532 4,624 SH   SOLE   4,624 0 0
FASTENAL CO COM 311900104 441,210 9,391,446 SH   SOLE   9,391,446 0 0
GOLDMAN SACHS GROUP INC COM 38141G104 171,340 715,555 SH   SOLE   715,555 0 0
GRAHAM HLDGS CO COM 384637104 1,653 3,228 SH   SOLE   3,228 0 0
HDFC BANK LTD ADR REPS 3 SHS 40415F101 946 15,592 SH   SOLE   15,592 0 0
HOME DEPOT INC COM 437076102 2,212 16,500 SH   SOLE   16,500 0 0
IAC INTERACTIVECORP COM 44919P508 78,090 1,205,275 SH   SOLE   1,205,275 0 0
IDEXX LABS INC COM 45168D104 3,253 27,741 SH   SOLE   27,741 0 0
INTERACTIVE BROKERS GROUP IN COM 45841N107 36,580 1,001,923 SH   SOLE   1,001,923 0 0
INTERNATIONAL BUSINESS MACHS COM 459200101 563 3,392 SH   SOLE   3,392 0 0
IRSA INVERSIONES Y REP S A GLOBL DEP RCPT 450047204 7,794 422,650 SH   SOLE   422,650 0 0
JACOBS ENGR GROUP INC DEL COM 469814107 281,325 4,935,528 SH   SOLE   4,935,528 0 0
JD COM INC SPON ADR CL A 47215P106 45,538 1,790,000 SH   SOLE   1,790,000 0 0
JOHNSON & JOHNSON COM 478160104 603 5,238 SH   SOLE   5,238 0 0
JPMORGAN CHASE & CO COM 46625H100 43,948 509,309 SH   SOLE   509,309 0 0
JPMORGAN CHASE & CO *W EXP 10/28/201 46634E114 61,978 1,400,000 SH   SOLE   1,400,000 0 0
LENNOX INTL INC COM 526107107 1,645 10,738 SH   SOLE   10,738 0 0
LIBERTY GLOBAL PLC SHS CL A G5480U104 6,932 226,598 SH   SOLE   226,598 0 0
LIBERTY MEDIA CORP DELAWARE COM A MEDIA GRP 531229870 4,157 132,612 SH   SOLE   132,612 0 0
LIBERTY MEDIA CORP DELAWARE COM C MEDIA GRP 531229854 280 8,953 SH   SOLE   8,953 0 0
LKQ CORP COM 501889208 5,517 180,000 SH   SOLE   180,000 0 0
MAKEMYTRIP LIMITED MAURITIUS SHS V5633W109 53,519 2,410,750 SH   SOLE   2,410,750 0 0
MASTERCARD INCORPORATED CL A 57636Q104 509,312 4,932,805 SH   SOLE   4,932,805 0 0
MCDONALDS CORP COM 580135101 1,563 12,845 SH   SOLE   12,845 0 0
MEDTRONIC PLC SHS G5960L103 214 3,000 SH   SOLE   3,000 0 0
MICROSOFT CORP COM 594918104 978 15,733 SH   SOLE   15,733 0 0
MOHAWK INDS INC COM 608190104 367,935 1,842,625 SH   SOLE   1,842,625 0 0
NOVO-NORDISK A S ADR 670100205 1,567 43,687 SH   SOLE   43,687 0 0
O REILLY AUTOMOTIVE INC NEW COM 67103H107 506,471 1,819,154 SH   SOLE   1,819,154 0 0
OCH ZIFF CAP MGMT GROUP CL A 67551U105 2,587 781,620 SH   SOLE   781,620 0 0
OMNICOM GROUP INC COM 681919106 183,238 2,152,957 SH   SOLE   2,152,957 0 0
PEPSICO INC COM 713448108 3,231 30,882 SH   SOLE   30,882 0 0
PERRIGO CO PLC SHS G97822103 109,470 1,315,276 SH   SOLE   1,315,276 0 0
PRAXAIR INC COM 74005P104 39,233 334,782 SH   SOLE   334,782 0 0
PRIMERICA INC COM 74164M108 208,055 3,008,752 SH   SOLE   3,008,752 0 0
PROCTER AND GAMBLE CO COM 742718109 4,656 55,380 SH   SOLE   55,380 0 0
PROGRESSIVE CORP OHIO COM 743315103 711 20,019 SH   SOLE   20,019 0 0
RYANAIR HLDGS PLC SPONSORED ADR NE 783513203 435 5,225 SH   SOLE   5,225 0 0
SCHLUMBERGER LTD COM 806857108 2,824 33,642 SH   SOLE   33,642 0 0
SCHWAB CHARLES CORP NEW COM 808513105 332,633 8,427,500 SH   SOLE   8,427,500 0 0
SIGNET JEWELERS LIMITED SHS G81276100 287 3,046 SH   SOLE   3,046 0 0
THIRD PT REINS LTD COM G8827U100 34,987 3,029,190 SH   SOLE   3,029,190 0 0
TIFFANY & CO NEW COM 886547108 159,602 2,061,244 SH   SOLE   2,061,244 0 0
TIME WARNER INC COM NEW 887317303 12,829 132,898 SH   SOLE   132,898 0 0
TJX COS INC NEW COM 872540109 743,861 9,900,983 SH   SOLE   9,900,983 0 0
TOLL BROTHERS INC COM 889478103 8,370 270,000 SH   SOLE   270,000 0 0
TRIMBLE INC COM 896239100 445 14,755 SH   SOLE   14,755 0 0
TRUPANION INC COM 898202106 27,853 1,794,650 SH   SOLE   1,794,650 0 0
UNION PAC CORP COM 907818108 6,200 59,800 SH   SOLE   59,800 0 0
VANGUARD BD INDEX FD INC SHORT TRM BOND 921937827 258 3,247 SH   SOLE   3,247 0 0
VANGUARD BD INDEX FD INC TOTAL BND MRKT 921937835 523 6,476 SH   SOLE   6,476 0 0
VISA INC COM CL A 92826C839 160,681 2,059,488 SH   SOLE   2,059,488 0 0
WATERS CORP COM 941848103 230,945 1,718,469 SH   SOLE   1,718,469 0 0
WAYFAIR INC CL A 94419L101 13,347 380,788 SH   SOLE   380,788 0 0
WELLS FARGO & CO NEW COM 949746101 287,290 5,213,029 SH   SOLE   5,213,029 0 0
WEST PHARMACEUTICAL SVSC INC COM 955306105 31,708 373,781 SH   SOLE   373,781 0 0
WOODWARD INC COM 980745103 718 10,401 SH   SOLE   10,401 0 0
YANDEX N V SHS CLASS A N97284108 54,419 2,703,355 SH   SOLE   2,703,355 0 0