# DUDLEY & SHANLEY, INC.

> Institutional holdings reported to the SEC as of Q3 2026 on Form 13F. CIK 883511. Source: https://holderbook.com/funds/883511-dudley-shanley-inc/

- Reported value: $629.2M
- Positions: 36
- Weight of the ten largest: 46.4%
- Filed: 2026-10-06

A 13F reports long US equity positions only. Short positions, bonds, foreign listings, private holdings and cash are not visible, so this is not the manager's whole book.

## Holdings

| Security | Ticker | Value | Shares | Weight | Quarters held |
|---|---|---|---|---|---|
| WHEATON PRECIOUS METALS CORP | [WPM](https://holderbook.com/stocks/WPM/) | $56.4M | 421,408 | 9.0% | 29 |
| AMETEK INC | [AME](https://holderbook.com/stocks/AME/) | $31.5M | 127,243 | 5.0% | 32 |
| VISA INC | [V](https://holderbook.com/stocks/V/) | $30.3M | 84,419 | 4.8% | 20 |
| ECOLAB INC | [ECL](https://holderbook.com/stocks/ECL/) | $27.2M | 99,043 | 4.3% | 32 |
| SERVICE CORP INTL | [SCI](https://holderbook.com/stocks/SCI/) | $26.1M | 342,425 | 4.1% | 32 |
| AMPHENOL CORP | [APH](https://holderbook.com/stocks/APH/) | $25.9M | 307,828 | 4.1% | 16 |
| ANALOG DEVICES INC | [ADI](https://holderbook.com/stocks/ADI/) | $25.6M | 64,639 | 4.1% | 15 |
| AON PLC | [AON](https://holderbook.com/stocks/AON/) | $23.6M | 85,202 | 3.7% | 27 |
| DONALDSON INC | [DCI](https://holderbook.com/stocks/DCI/) | $22.6M | 260,170 | 3.6% | 11 |
| FASTENAL CO | [FAST](https://holderbook.com/stocks/FAST/) | $22.5M | 454,940 | 3.6% | 4 |
| FERGUSON ENTERPRISES INC | [FERG](https://holderbook.com/stocks/FERG/) | $22.3M | 100,032 | 3.5% | 8 |
| PROGRESSIVE CORP | [PGR](https://holderbook.com/stocks/PGR/) | $21.6M | 104,152 | 3.4% | 28 |
| AMERICAN WTR WKS CO INC NEW | [AWK](https://holderbook.com/stocks/AWK/) | $20.8M | 160,550 | 3.3% | 15 |
| SCHWAB CHARLES CORP | [SCHW](https://holderbook.com/stocks/SCHW/) | $20.7M | 211,965 | 3.3% | 11 |
| TYLER TECHNOLOGIES INC | [TYL](https://holderbook.com/stocks/TYL/) | $20.5M | 64,400 | 3.3% | 1 |
| ROPER TECHNOLOGIES INC | [ROP](https://holderbook.com/stocks/ROP/) | $20.0M | 57,325 | 3.2% | 32 |
| ALLISON TRANSMISSION HLDGS I | [ALSN](https://holderbook.com/stocks/ALSN/) | $19.9M | 175,274 | 3.2% | 22 |
| KORNIT DIGITAL LTD | [KRNT](https://holderbook.com/stocks/KRNT/) | $19.4M | 1,168,545 | 3.1% | 16 |
| FEDERAL SIGNAL CORP | [FSS](https://holderbook.com/stocks/FSS/) | $19.3M | 174,050 | 3.1% | 3 |
| KADANT INC | [KAI](https://holderbook.com/stocks/KAI/) | $19.0M | 72,782 | 3.0% | 16 |
| XYLEM INC | [XYL](https://holderbook.com/stocks/XYL/) | $17.2M | 170,310 | 2.7% | 3 |
| RYAN SPECIALTY HOLDINGS INC | [RYAN](https://holderbook.com/stocks/RYAN/) | $17.2M | 465,889 | 2.7% | 20 |
| DANAHER CORP DEL | [DHR](https://holderbook.com/stocks/DHR/) | $15.8M | 71,195 | 2.5% | 27 |
| WATSCO INC | [WSO](https://holderbook.com/stocks/WSO/) | $15.6M | 51,565 | 2.5% | 15 |
| NEXGEN ENERGY LTD | [NXE](https://holderbook.com/stocks/NXE/) | $11.2M | 1,225,500 | 1.8% | 32 |
| AGILENT TECHNOLOGIES INC | [A](https://holderbook.com/stocks/A/) | $11.1M | 64,550 | 1.8% | 9 |
| BADGER METER INC | [BMI](https://holderbook.com/stocks/BMI/) | $10.5M | 84,600 | 1.7% | 4 |
| WATERS CORP | [WAT](https://holderbook.com/stocks/WAT/) | $10.4M | 23,590 | 1.6% | 3 |
| HEICO CORP NEW | [HEI](https://holderbook.com/stocks/HEI/) | $5.8M | 19,000 | 0.9% | 20 |
| MICROSOFT CORP | [MSFT](https://holderbook.com/stocks/MSFT/) | $5.4M | 10,569 | 0.9% | 32 |
| PFIZER INC | [PFE](https://holderbook.com/stocks/PFE/) | $4.7M | 165,000 | 0.7% | 2 |
| GENERAC HLDGS INC | [GNRC](https://holderbook.com/stocks/GNRC/) | $3.3M | 16,150 | 0.5% | 16 |
| FISERV INC | [FISV](https://holderbook.com/stocks/FISV/) | $2.8M | 62,449 | 0.4% | 32 |
| ORMAT TECHNOLOGIES INC | [ORA](https://holderbook.com/stocks/ORA/) | $2.4M | 26,100 | 0.4% | 20 |
| VIPER ENERGY INC | [VNOM](https://holderbook.com/stocks/VNOM/) | $307.2K | 7,700 | 0.0% | 4 |
| ATHA Energy Corp. | [SASKF](https://holderbook.com/stocks/SASKF/) | $79.8K | 118,000 | 0.0% | 3 |

## What the disclosed book did

Not the fund's return. This is the change in value of the positions disclosed on Form 13F, had they been left untouched, against SPY over the same quarter ends.

| Quarter | Book | Market | Difference | Priced |
|---|---|---|---|---|
| Q2 2026 | +4.3% | +14.8% | -10.6% | 100% |
| Q1 2026 | -1.5% | -4.6% | +3.2% | 100% |
| Q4 2025 | +0.2% | +2.4% | -2.1% | 100% |
| Q3 2025 | +2.4% | +7.8% | -5.4% | 100% |
| Q2 2025 | +4.6% | +10.5% | -5.8% | 100% |
| Q1 2025 | +3.6% | -4.6% | +8.2% | 100% |
| Q4 2024 | -1.8% | +2.1% | -4.0% | 100% |
| Q3 2024 | +10.2% | +5.4% | +4.8% | 100% |

## Quarter by quarter

| Quarter | Value | Positions |
|---|---|---|
| Q3 2026 | $629.2M | 36 |
| Q2 2026 | $662.3M | 37 |
| Q1 2026 | $611.2M | 37 |
| Q4 2025 | $622.2M | 33 |
| Q3 2025 | $621.5M | 32 |
| Q2 2025 | $636.8M | 36 |
| Q1 2025 | $635.1M | 36 |
| Q4 2024 | $647.6M | 37 |
| Q3 2024 | $639.7M | 36 |
| Q2 2024 | $581.9M | 36 |
| Q1 2024 | $592.6M | 36 |
| Q4 2023 | $561.0M | 34 |