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
ALIBABA GROUP HLDG LTDSPONSORED ADS01609W102162,390552,383SH SOLE 552,38300
ALPHABET INCCAP STK CL A02079K30563,17843,107SH SOLE 43,10700
ALPHABET INCCAP STK CL C02079K10763,16542,981SH SOLE 42,98100
AMAZON COM INCCOM023135106190,37260,460SH SOLE 60,46000
APPLE INCCOM037833100232,1042,004,176SH SOLE 2,004,17600
BERKSHIRE HATHAWAY INC DELCL B NEW08467070210,030,41147,104,399SH SOLE 47,104,39900
BOSTON PROPERTIES INCCOM10112110188,2751,099,310SH SOLE 1,099,31000
CANADIAN NATL RY COCOM1363751021,823,32717,126,874SH SOLE 17,126,87400
CATERPILLAR INC DELCOM1491231011,679,55711,260,857SH SOLE 11,260,85700
COCA-COLA FEMSA SAB DE CVSPONSORD ADR REP191241108253,0636,214,719SH SOLE 6,214,71900
CROWN CASTLE INTL CORP NEWCOM22822V101887,9285,332,900SH SOLE 5,332,90000
ECOLAB INCCOM278865100872,5874,366,426SH SOLE 4,366,42600
FEDEX CORPCOM31428X106760,8483,024,999SH SOLE 3,024,99900
GRUPO TELEVISA SASPON ADR REP ORD40049J206104,31316,879,104SH SOLE 16,879,10400
LIBERTY GLOBAL PLCSHS CL AG5480U10444,5312,119,515SH SOLE 2,119,51500
LIBERTY GLOBAL PLCSHS CL CG5480U12074,7343,639,349SH SOLE 3,639,34900
LIBERTY LATIN AMERICA LTDCOM CL AG9001E1023,056370,424SH SOLE 370,42400
LIBERTY LATIN AMERICA LTDCOM CL CG9001E1287,613935,282SH SOLE 935,28200
SCHRODINGER INCCOM80810D103236,6794,981,664SH SOLE 4,981,66400
TWITTER INCCOM90184L10212,123272,420SH SOLE 272,42000
UBER TECHNOLOGIES INCCOM90353T10097626,767SH SOLE 26,76700
UNITED PARCEL SERVICE INCCL B911312106754,0564,525,329SH SOLE 4,525,32900
WALMART INCCOM9311421031,623,37611,603,000SH SOLE 11,603,00000
WASTE MGMT INC DELCOM94106L1092,108,77318,633,672SH SOLE 18,633,67200