Carderock Capital Management 13F-HR Quarterly holdings report by institutional manager

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	(x$1000)	PRN AMT	PRN	CALL	DISCRETION	MANAGER	SOLE	SHARED	NONE
Abbott Laboratories	COM	002824100	7,056	58,877	SH		SOLE		0	0	58,877
Accenture PLC Cl A	COM	G1151C101	11,836	42,847	SH		SOLE		0	0	42,847
Adobe Inc	COM	00724F101	8,896	18,714	SH		SOLE		0	0	18,714
Air Products & Chemicals	COM	009158106	5,023	17,854	SH		SOLE		0	0	17,854
Alphabet Inc	COM	02079K305	7,693	3,730	SH		SOLE		0	0	3,730
Amazon.com	COM	023135106	1,581	511	SH		SOLE		0	0	511
American Tower Corp	COM	03027X100	4,798	20,071	SH		SOLE		0	0	20,071
Ametek	COM	031100100	5,315	41,612	SH		SOLE		0	0	41,612
Amgen	COM	031162100	6,427	25,831	SH		SOLE		0	0	25,831
Amphenol Corp	COM	032095101	7,896	119,686	SH		SOLE		0	0	119,686
Ansys	COM	03662Q105	7,945	23,398	SH		SOLE		0	0	23,398
Aon PLC	COM	G0403H108	5,853	25,434	SH		SOLE		0	0	25,434
Apple Computer	COM	037833100	17,829	145,962	SH		SOLE		0	0	145,962
Aptargroup	COM	038336103	2,723	19,221	SH		SOLE		0	0	19,221
Automatic Data Proc	COM	053015103	4,615	24,489	SH		SOLE		0	0	24,489
Becton Dickinson & Co	COM	075887109	5,044	20,744	SH		SOLE		0	0	20,744
Berkshire Hathaway Cl B	COM	084670702	281	1,100	SH		SOLE		0	0	1,100
Bristol-Myers Squibb	COM	110122108	237	3,750	SH		SOLE		0	0	3,750
Cadence Design Sys	COM	127387108	4,580	33,433	SH		SOLE		0	0	33,433
Canadian National Railway Corp	COM	136375102	1,816	15,660	SH		SOLE		0	0	15,660
Chevron Texaco Corp	COM	166764100	391	3,731	SH		SOLE		0	0	3,731
Church & Dwight	COM	171340102	5,942	68,028	SH		SOLE		0	0	68,028
Cintas Corp	COM	172908105	3,419	10,018	SH		SOLE		0	0	10,018
Clorox Co	COM	189054109	294	1,525	SH		SOLE		0	0	1,525
Comcast Corp Cl A	COM	20030N101	1,640	30,312	SH		SOLE		0	0	30,312
Costar Group Com	COM	22160N109	2,498	3,039	SH		SOLE		0	0	3,039
Costco Wholesale	COM	22160K105	5,786	16,414	SH		SOLE		0	0	16,414
D R Horton Inc	COM	23331A109	932	10,456	SH		SOLE		0	0	10,456
Danaher Corp	COM	235851102	7,953	35,332	SH		SOLE		0	0	35,332
Ecolab	COM	278865100	5,582	26,074	SH		SOLE		0	0	26,074
Edward Lifesciences	COM	28176E108	3,838	45,882	SH		SOLE		0	0	45,882
Enphase Energy Inc	COM	29355A107	1,500	9,253	SH		SOLE		0	0	9,253
Equinix Inc REIT	COM	29444U700	1,787	2,630	SH		SOLE		0	0	2,630
Extra Space Storage	COM	30225T102	333	2,512	SH		SOLE		0	0	2,512
Exxon Mobil Corp	COM	30231G102	263	4,705	SH		SOLE		0	0	4,705
Fair Isaac Corp	COM	303250104	3,344	6,879	SH		SOLE		0	0	6,879
Fiserv	COM	337738108	6,303	52,949	SH		SOLE		0	0	52,949
Fortinet Inc	COM	34959E109	2,989	16,205	SH		SOLE		0	0	16,205
Garmin Ltd	COM	H2906T109	562	4,261	SH		SOLE		0	0	4,261
Home Depot	COM	437076102	6,563	21,501	SH		SOLE		0	0	21,501
Honeywell	COM	438516106	5,839	26,900	SH		SOLE		0	0	26,900
Idexx Labs	COM	45168D104	7,993	16,336	SH		SOLE		0	0	16,336
Illinois Tool Works	COM	452308109	5,570	25,143	SH		SOLE		0	0	25,143
Intuit	COM	461202103	7,851	20,496	SH		SOLE		0	0	20,496
J P Morgan Chase	COM	46625H100	3,974	26,106	SH		SOLE		0	0	26,106
Johnson & Johnson	COM	478160104	558	3,398	SH		SOLE		0	0	3,398
L3 Harris	COM	502431109	941	4,645	SH		SOLE		0	0	4,645
Laboratory Corp	COM	50540R409	6,660	26,116	SH		SOLE		0	0	26,116
Lauder Estee Cos Inc	COM	518439104	5,645	19,410	SH		SOLE		0	0	19,410
Marriott Intl New Cl A	COM	571903202	284	1,918	SH		SOLE		0	0	1,918
Mastercard Worldwide	COM	57636Q104	9,084	25,514	SH		SOLE		0	0	25,514
McCormick & Co	COM	579780206	5,460	61,242	SH		SOLE		0	0	61,242
Merck & Co New	COM	58933Y105	227	2,951	SH		SOLE		0	0	2,951
Mettler Toledo Intl	COM	592688105	6,170	5,339	SH		SOLE		0	0	5,339
Microsoft Corp	COM	594918104	9,821	41,656	SH		SOLE		0	0	41,656
Moody's Corp	COM	615369105	3,983	13,337	SH		SOLE		0	0	13,337
NextEra Energy	COM	65339F101	2,956	39,096	SH		SOLE		0	0	39,096
Nike Cl B	COM	654106103	7,668	57,705	SH		SOLE		0	0	57,705
O'Reilly Automotive New	COM	67103H107	3,949	7,785	SH		SOLE		0	0	7,785
Paychex	COM	704326107	582	5,935	SH		SOLE		0	0	5,935
Roper Technologies Inc	COM	776696106	5,109	12,666	SH		SOLE		0	0	12,666
S&P Global Inc	COM	78409V104	5,031	14,258	SH		SOLE		0	0	14,258
Sherwin-Williams Co	COM	824348106	4,702	6,371	SH		SOLE		0	0	6,371
Solaredge Tech	COM	83417M104	2,075	7,219	SH		SOLE		0	0	7,219
Starbucks Corp	COM	855244109	4,193	38,377	SH		SOLE		0	0	38,377
T-Mobile US Inc	COM	872590104	442	3,531	SH		SOLE		0	0	3,531
TRPrice Assoc	COM	74144T108	1,360	7,925	SH		SOLE		0	0	7,925
Taiwan Semiconductor	COM	874039100	14,046	118,755	SH		SOLE		0	0	118,755
Teleflex	COM	879369106	312	752	SH		SOLE		0	0	752
Thermo Fisher Scientific	COM	883556102	8,413	18,434	SH		SOLE		0	0	18,434
Toro Co	COM	891092108	6,307	61,153	SH		SOLE		0	0	61,153
Truist Finl Corp	COM	89832Q109	200	3,437	SH		SOLE		0	0	3,437
Union Pacific Corp	COM	907818108	464	2,104	SH		SOLE		0	0	2,104
UnitedHealth Grp	COM	91324P102	4,454	11,970	SH		SOLE		0	0	11,970
VISA Inc Com Cl A	COM	92826C839	252	1,192	SH		SOLE		0	0	1,192
Verizon Communication	COM	92343v104	209	3,594	SH		SOLE		0	0	3,594
Walt Disney Company	COM	254687106	207	1,120	SH		SOLE		0	0	1,120
Waste Connections Inc	COM	94106B101	2,372	21,971	SH		SOLE		0	0	21,971