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
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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 FIGI (to the nearest dollar) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
Abbott Laboratories COM 002824100   559,555 5,385 SH   SOLE   0 0 5,385
Accenture PLC Cl A COM G1151C101   6,367,059 20,985 SH   SOLE   0 0 20,985
Air Products & Chemicals COM 009158106   6,288,162 24,368 SH   SOLE   0 0 24,368
Alphabet Inc COM 02079K305   12,082,374 66,332 SH   SOLE   0 0 66,332
Ametek COM 031100100   7,768,519 46,599 SH   SOLE   0 0 46,599
Amphenol Corp COM 032095101   11,625,300 172,559 SH   SOLE   0 0 172,559
Ansys COM 03662Q105   2,587,432 8,048 SH   SOLE   0 0 8,048
Aon PLC COM G0403H108   5,513,432 18,780 SH   SOLE   0 0 18,780
Apple Computer COM 037833100   12,386,773 58,811 SH   SOLE   0 0 58,811
Arch Cap Group Ltd COM G0450A105   9,710,864 96,252 SH   SOLE   0 0 96,252
Arthur J. Gallagher & Co COM 363576109   311,172 1,200 SH   SOLE   0 0 1,200
Automatic Data Proc COM 053015103   7,651,924 32,058 SH   SOLE   0 0 32,058
Berkshire Hathaway Cl B COM 084670702   396,630 975 SH   SOLE   0 0 975
CSX Corp COM 126408103   229,132 6,850 SH   SOLE   0 0 6,850
Cadence Design Sys COM 127387108   10,091,430 32,791 SH   SOLE   0 0 32,791
Chevron Corp COM 166764100   673,701 4,307 SH   SOLE   0 0 4,307
Chipotle Mexican Grill COM 169656105   7,214,147 115,150 SH   SOLE   0 0 115,150
Church & Dwight COM 171340102   5,860,927 56,529 SH   SOLE   0 0 56,529
Cintas Corp COM 172908105   11,489,166 16,407 SH   SOLE   0 0 16,407
Coca Cola Co COM 191216100   206,862 3,250 SH   SOLE   0 0 3,250
Costco Wholesale Co COM 22160K105   9,244,491 10,876 SH   SOLE   0 0 10,876
Danaher Corp COM 235851102   5,277,831 21,124 SH   SOLE   0 0 21,124
Digital Realty Trust REIT COM 253868103   258,485 1,700 SH   SOLE   0 0 1,700
Exxon Mobil Corp COM 30231G102   429,743 3,733 SH   SOLE   0 0 3,733
Fair Isaac Corp COM 303250104   9,183,544 6,169 SH   SOLE   0 0 6,169
Fiserv COM 337738108   8,011,794 53,756 SH   SOLE   0 0 53,756
Fortinet Inc COM 34959E109   8,146,334 135,164 SH   SOLE   0 0 135,164
Freeport-McMoran Copper & Gold COM 35671D857   243,000 5,000 SH   SOLE   0 0 5,000
Grainger (WW) COM 384802104   3,877,828 4,298 SH   SOLE   0 0 4,298
Heico Corp COM 422806109   8,115,254 36,292 SH   SOLE   0 0 36,292
Hershey Foods Corp COM 427866108   3,301,403 17,959 SH   SOLE   0 0 17,959
Home Depot COM 437076102   7,020,431 20,394 SH   SOLE   0 0 20,394
Honeywell Intl Inc COM 438516106   1,049,549 4,915 SH   SOLE   0 0 4,915
Idex Corp COM 45167R104   225,746 1,122 SH   SOLE   0 0 1,122
Idexx Labs COM 45168d104   7,193,021 14,764 SH   SOLE   0 0 14,764
Illinois Tool Works COM 452308109   4,913,366 20,735 SH   SOLE   0 0 20,735
Ingersoll Rand COM 45687V106   6,992,318 76,974 SH   SOLE   0 0 76,974
Intuit COM 461202103   7,249,026 11,030 SH   SOLE   0 0 11,030
Intuitive Surgical COM 46120E602   9,593,635 21,566 SH   SOLE   0 0 21,566
Johnson & Johnson COM 478160104   219,240 1,500 SH   SOLE   0 0 1,500
Lam Research Corp COM 512807108   11,532,325 10,830 SH   SOLE   0 0 10,830
Lilly Eli & Co COM 532457108   7,030,276 7,765 SH   SOLE   0 0 7,765
Lockheed Martin Corp COM 539830109   1,956,682 4,189 SH   SOLE   0 0 4,189
Marriott Intl New Cl A COM 571903202   415,361 1,718 SH   SOLE   0 0 1,718
Mastercard Worldwide COM 57636Q104   11,398,251 25,837 SH   SOLE   0 0 25,837
Mettler Toledo Intl COM 592688105   1,477,253 1,057 SH   SOLE   0 0 1,057
Microsoft Corp COM 594918104   13,980,149 31,279 SH   SOLE   0 0 31,279
Monolithic Power Systems COM 609839105   7,862,656 9,569 SH   SOLE   0 0 9,569
Monster Beverage Corp COM 61174X109   1,891,906 37,876 SH   SOLE   0 0 37,876
Moody's Corp COM 615369105   8,491,842 20,174 SH   SOLE   0 0 20,174
Nvidia Corp COM 67066G104   3,839,129 31,076 SH   SOLE   0 0 31,076
O'Reilly Automotive New COM 67103H107   8,208,754 7,773 SH   SOLE   0 0 7,773
Parker Hannifin Corp COM 701094104   10,573,958 20,905 SH   SOLE   0 0 20,905
Paychex COM 704326107   349,752 2,950 SH   SOLE   0 0 2,950
Quanta Svcs COM 74762e102   7,602,627 29,921 SH   SOLE   0 0 29,921
Roper Technologies Inc COM 776696106   7,715,942 13,689 SH   SOLE   0 0 13,689
S&P Global Inc COM 78409V104   8,676,930 19,455 SH   SOLE   0 0 19,455
Sherwin-Williams Co COM 824348106   7,845,426 26,289 SH   SOLE   0 0 26,289
Steris PLC COM g8473t100   7,009,693 31,929 SH   SOLE   0 0 31,929
Stryker Corp COM 863667101   6,397,380 18,802 SH   SOLE   0 0 18,802
TRPrice Assoc COM 74144T108   1,164,631 10,100 SH   SOLE   0 0 10,100
Thermo Fisher Scientific COM 883556102   6,572,958 11,886 SH   SOLE   0 0 11,886
UnitedHealth Grp COM 91324P102   5,321,767 10,450 SH   SOLE   0 0 10,450
Waste Connections Inc COM 94106B101   7,478,753 42,648 SH   SOLE   0 0 42,648
Watsco COM 942622200   5,163,736 11,147 SH   SOLE   0 0 11,147
iShares Dow Jones Select Div F COM 464287168   213,651 1,766 SH   SOLE   0 0 1,766
iShares US Tech ETF COM 464287721   451,500 3,000 SH   SOLE   0 0 3,000
DFA US Core Equity 1 ISHARES 233203413   213,262 5,281 SH   SOLE   0 0 5,281
Vanguard 500 Index Fd ISHARES 922908710   1,761,994 3,498 SH   SOLE   0 0 3,498