13F Insight
DOSSIER · 13F-HR · Q3 2026

DUDLEY & SHANLEY, INC.

$629M in tracked AUM across 37 positions as of Q3 2026.

D&
CIK 0000883511 · last filed Sep 30, 2026
Total AUM
$629M
as of Q3 2026
Holdings
37
—
positions
Whale Score
63
63
tracked
Activity
—
no data
changes this Q
AI Analysis · Q3 2026

SEC 13F Filing Analysis: Dudley & Shanley, Inc. Report Period: Q4 2025 (Report Date: 2025-12-31)

1. Portfolio Overview

Dudley & Shanley, Inc. has reported a significant transformation in its investment portfolio for the quarter ending December 31, 2025. The firm experienced a substantial increase in assets under management (AUM), with the total portfolio value surging by 217.3%, rising from $196.07M to $622.21M. This dramatic capital infusion coincides with a strategic o...

The portfolio remains relatively concentrated, holding 34 securities. However, the construction of the portfolio is balanced; no single position exceeds 13% of the total value, and the top 10 holdings account for approximately 55% of the portfolio. The fund demonstrates a "core-satellite" approach where a significant portion of capital is deployed into high-conviction, large-cap industrial and technology names, supplemented by smaller positions in specialized sectors like water utilities and uranium.

2. Key Holdings

The top holdings reflect a strong preference for quality compounders and industry leaders, particularly within the industrials and technology sectors.

Analysis generated by 13F Insight from SEC Form 13F filing data · Q3 2026. Methodology

Quarter at a glance — Q3 2026

Position-change comparison pending.

No quarter-over-quarter changes available.

Top 10 holdings

By portfolio weight as of Q3 2026.

#HoldingValueSharesWeight
01
WPM
Wheaton Precious Mtls
$56M421K9.0%02
AME
Ametek Inc.
$32M127K5.0%03
V
Visa Inc.
$30M84K4.8%04
ECL
Ecolab Inc.
$27M99K4.3%05
SCI
Service Corp. Int'l
$26M342K4.1%06
APH
Amphenol Corp.
$26M308K4.1%07
ADI
Analog Devices
$26M65K4.1%08
G0403H108
Aon plc
$24M85K3.7%09
DCI
Donaldson Co., Inc.
$23M260K3.6%10
FAST
Fastenal Co.
$23M455K3.6%

Filing history

2026Q3Sep 30
$629M▼ 5.0%
37 positionsView →2026Q2Jun 30
$662M▲ 8.4%
38 positionsView →2026Q1Mar 31
$611M▼ 1.8%
38 positionsView →2025Q4Dec 31
$622M▲ 0.1%
34 positionsView →2025Q3Sep 30
$622M▼ 2.4%
33 positionsLocked2025Q2Jun 30
$637M▲ 0.3%
37 positionsLocked2025Q1Mar 31
$635M▼ 1.9%
37 positionsLocked2024Q4Dec 31
$648M▲ 1.2%
38 positionsLocked2024Q3Sep 30
$640M▲ 9.9%
37 positionsLocked2024Q2Jun 30
$582M▼ 1.8%
37 positionsLocked2024Q1Mar 31
$593M▲ 5.6%
37 positionsLocked2023Q4Dec 31
$561M▲ 6.1%
35 positionsLocked
Showing 12 of 100