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

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COLUMN 1COLUMN 2COLUMN 3COLUMN 4COLUMN 5COLUMN 6COLUMN 7COLUMN 8
VALUESHRS ORSH/PUT/INVESTMENTOTHERVOTING AUTHORITY
NAME OF ISSUERTITLE OF CLASSCUSIP(x$1000)PRN AMTPRNCALLDISCRETIONMANAGERSOLESHAREDNONE
ALPHABET INCCAP STK CL A02079K30537,77621,554SH SOLE 21,55400
ALPHABET INCCAP STK CL C02079K10737,65021,491SH SOLE 21,49100
AMAZON COM INCCOM02313510698,45730,230SH SOLE 30,23000
APPLE INCCOM037833100132,9671,002,088SH SOLE 1,002,08800
BERKSHIRE HATHAWAY INC DELCL B NEW0846707029,762,74742,104,399SH SOLE 42,104,39900
CANADIAN NATL RY COCOM1363751021,865,17316,979,268SH SOLE 16,979,26800
CATERPILLAR INCCOM1491231012,049,70111,260,857SH SOLE 11,260,85700
COCA-COLA FEMSA SAB DE CVSPONSORD ADR REP191241108286,4996,214,719SH SOLE 6,214,71900
CROWN CASTLE INTL CORP NEWCOM22822V101848,9445,332,900SH SOLE 5,332,90000
ECOLAB INCCOM278865100944,7204,366,426SH SOLE 4,366,42600
FEDEX CORPCOM31428X106785,3503,024,999SH SOLE 3,024,99900
GRUPO TELEVISA SASPON ADR REP ORD40049J206139,08416,879,104SH SOLE 16,879,10400
LIBERTY GLOBAL PLCSHS CL AG5480U10451,3352,119,515SH SOLE 2,119,51500
LIBERTY GLOBAL PLCSHS CL CG5480U12086,0713,639,349SH SOLE 3,639,34900
LIBERTY LATIN AMERICA LTDCOM CL AG9001E1023,077276,443SH SOLE 276,44300
LIBERTY LATIN AMERICA LTDCOM CL CG9001E1287,508676,979SH SOLE 676,97900
SCHRODINGER INCCOM80810D103552,8086,981,664SH SOLE 6,981,66400
TWITTER INCCOM90184L10214,752272,420SH SOLE 272,42000
UNITED PARCEL SERVICE INCCL B911312106762,0654,525,329SH SOLE 4,525,32900
WALMART INCCOM9311421031,672,57211,603,000SH SOLE 11,603,00000
WASTE MGMT INC DELCOM94106L1092,197,46918,633,672SH SOLE 18,633,67200