Carderock Capital Management Inc reported 68 positions worth $434.34M for the quarter ended Sep 30, 2026, down 4.5% on the prior quarter. It opened 6 new positions, added to 18, trimmed 33 and exited 3. Its largest holding is Lam Research Corp at 4.8% of the portfolio.
Reported 13F market value at each quarter end. A change mixes trading with price moves in the positions held.
Dollar value of shares bought and sold each quarter, at that quarter’s price. It counts trading only, not price changes.
How many positions were opened, added to, trimmed or closed each quarter.
Share of reported value in each sector at every quarter end.
| Holding | Change | Change % | Trade Value | Weight |
|---|---|---|---|---|
| WAT Waters Corp | +6,987 | +94.2% | $3.07M | 1.46% |
| AMZN Amazon Com Inc | +7,652 | – | $1.91M | 0.439% |
| MSFT Microsoft Corp | +2,521 | +9.2% | $1.29M | 3.54% |
| BR Broadridge Financial Solutions, Inc. | +6,928 | – | $1.12M | 0.257% |
| AJG Arthur J. Gallagher & Co. | +4,617 | +28.3% | $1.05M | 1.1% |
| VMC Vulcan Materials CO | +3,696 | – | $904.15K | 0.208% |
| ETN Eaton Corp plc | +2,037 | +22.2% | $875.32K | 1.11% |
| MA Mastercard Inc | +1,367 | +5.6% | $753.86K | 3.27% |
| AZN Astrazeneca Plc | +4,282 | – | $691.42K | 0.159% |
| CMI Cummins Inc | +1,184 | – | $611.62K | 0.141% |
| Holding | Change | Change % | Trade Value | Weight |
|---|---|---|---|---|
| WSO Watsco Inc | -11.5K | -100.0% | $4.80M | Exited |
| LRCX Lam Research Corp | -10.2K | -13.8% | $3.34M | 4.81% |
| HD Home Depot, Inc. | -8,453 | -42.2% | $2.40M | 0.758% |
| FTNT Fortinet, Inc. | -10.2K | -11.1% | $1.82M | 3.34% |
| MPWR Monolithic Power Systems, Inc. | -1,247 | -12.1% | $1.68M | 2.81% |
| PWR Quanta Services, Inc. | -2,095 | -10.7% | $1.35M | 2.59% |
| ISRG Intuitive Surgical Inc | -2,905 | -16.0% | $1.18M | 1.43% |
| APH Amphenol Corp | -13.7K | -6.4% | $1.15M | 3.87% |
| PH Parker-Hannifin Corp | -1,092 | -9.8% | $1.04M | 2.2% |
| GWW W.W. Grainger, Inc. | -679 | -9.9% | $845.87K | 1.78% |
| Holding | Shares | Trade Value | Weight |
|---|---|---|---|
| AMZN Amazon Com Inc | +7,652 | $1.91M | 0.439% |
| BR Broadridge Financial Solutions, Inc. | +6,928 | $1.12M | 0.257% |
| VMC Vulcan Materials CO | +3,696 | $904.15K | 0.208% |
| AZN Astrazeneca Plc | +4,282 | $691.42K | 0.159% |
| CMI Cummins Inc | +1,184 | $611.62K | 0.141% |
| HCA HCA Healthcare, Inc. | +1,182 | $504.41K | 0.116% |
| # | Activity | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | LRCX Lam Research Corp | Technology | 63.6K | $20.91M | 4.81% | -10.2K | -13.8% | Reduced | 0.01% |
| 2 | GOOGL Alphabet Inc. | Technology | 56.3K | $19.38M | 4.46% | -153 | -0.3% | Reduced | 0% |
| 3 | AAPL Apple Inc. | Technology | 51.0K | $16.97M | 3.91% | -946 | -1.8% | Reduced | 0% |
| 4 | APH Amphenol Corp | Industrials | 199.5K | $16.81M | 3.87% | -13.7K | -6.4% | Reduced | 0.01% |
| 5 | MSFT Microsoft Corp | Technology | 30.0K | $15.36M | 3.54% | +2,521 | +9.2% | Added | 0% |
| 6 | LLY ELI LILLY & Co | Healthcare | 12.7K | $14.67M | 3.38% | -139 | -1.1% | Reduced | 0% |
| 7 | FTNT Fortinet, Inc. | Technology | 81.2K | $14.52M | 3.34% | -10.2K | -11.1% | Reduced | 0.01% |
| 8 | TMO Thermo Fisher Scientific Inc. | Healthcare | 21.4K | $14.44M | 3.32% | +529 | +2.5% | Added | 0.01% |
| 9 | MA Mastercard Inc | Financial Services | 25.7K | $14.19M | 3.27% | +1,367 | +5.6% | Added | 0% |
| 10 | NVDA Nvidia Corp | Technology | 55.3K | $12.64M | 2.91% | -1,197 | -2.1% | Reduced | 0% |
| 11 | MPWR Monolithic Power Systems, Inc. | Technology | 9,054 | $12.20M | 2.81% | -1,247 | -12.1% | Reduced | 0.02% |
| 12 | HEI Heico Corp | Industrials | 39.1K | $11.85M | 2.73% | -1,008 | -2.5% | Reduced | 0.07% |
| 13 | AME Ametek Inc/ | Industrials | 46.5K | $11.52M | 2.65% | +662 | +1.4% | Added | 0.02% |
| 14 | PWR Quanta Services, Inc. | Industrials | 17.5K | $11.26M | 2.59% | -2,095 | -10.7% | Reduced | 0.01% |
| 15 | MNST Monster Beverage Corp | Consumer Staples | 246.9K | $10.28M | 2.37% | -1,802 | -0.7% | Reduced | 0.01% |
Tip. Select a row to see that position’s full history at Carderock Capital Management.
As of its Q3 2026 13F filing, Carderock Capital Management Inc’s five largest positions were Lam Research Corp (LRCX) at 4.8%, Alphabet Inc. (GOOGL) at 4.5%, Apple Inc. (AAPL) at 3.9%, Amphenol Corp (APH) at 3.9%, Microsoft Corp (MSFT) at 3.5% of the reported portfolio.
Carderock Capital Management Inc reported a 13F portfolio worth $434.34M across 68 positions for Q3 2026. That is down 4.5% from the previous quarter.
Its largest purchases by value were Waters Corp ($3.07M), Amazon Com Inc ($1.91M), Microsoft Corp ($1.29M). It opened 6 new positions.
Its largest sales by value were Watsco Inc ($4.80M), Lam Research Corp ($3.34M), Home Depot, Inc. ($2.40M). It exited 3 positions entirely.
From the Form 13F-HR reports Carderock Capital Management Inc files with the SEC each quarter, within 45 days of quarter end. A 13F lists long positions in US-listed equities and options; it excludes short positions, cash, bonds and most non-US holdings.
13F data reflects long positions in US-listed equities and options as reported to the SEC up to 45 days after quarter end. It excludes short positions, cash, bonds and most non-US securities, so it is not a complete picture of a manager’s assets.