Amphenol Corporation
US ˙ NYSE ˙ US0320951017

SecurityAPH / Amphenol Corporation
InstitutionDudley & Shanley, Inc.
Latest Disclosed Ownership245,751 shares
Latest Disclosed Value $ 31,050,639
Dudley & Shanley, Inc. reports 13.13% decrease in ownership of APH / Amphenol Corporation

On April 8, 2026 - Dudley & Shanley, Inc. filed a 13F-HR form disclosing ownership of 245,751 shares of Amphenol Corporation (US:APH) valued at $31,050,639 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 9, 2026 disclosing 282,911 shares of Amphenol Corporation. This represents a change in shares of -13.13% during the quarter. The current value of the position is $34,112,696 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-04-08 2026-03-31 13F Amphenol COM 032095101 245,751 -37,160 -13.13 31,051 -18.79 4.9109
2026-01-09 2025-12-31 13F Amphenol COM 032095101 282,911 -33,685 -10.64 38,233 -2.41 6.1447
2025-10-08 2025-09-30 13F Amphenol COM 032095101 316,596 -111,404 -26.03 39,179 -7.30 6.3038
2025-07-09 2025-06-30 13F Amphenol COM 032095101 428,000 -10,940 -2.49 42,265 46.80 6.6369
2025-04-09 2025-03-31 13F Amphenol COM 032095101 438,940 -10 -0.00 28,790 -5.56 4.5333
2025-01-03 2024-12-31 13F Amphenol COM 032095101 438,950 580 0.13 30,485 6.73 4.7077
2024-12-23 2024-09-30 13F Amphenol COM 032095101 438,370 1,700 0.39 28,564 -2.90 4.4652
2024-07-09 2024-06-30 13F Amphenol COM 032095101 436,670 214,215 96.30 29,418 14.65 5.0555
2024-04-19 2024-03-31 13F Amphenol COM 032095101 222,455 2,230 1.01 25,660 17.54 4.3299
2024-01-12 2023-12-31 13F Amphenol COM 032095101 220,225 -2,670 -1.20 21,831 16.61 3.8916
2023-10-13 2023-09-30 13F Amphenol COM 032095101 222,895 -5 -0.00 18,721 -1.14 3.5395
2023-07-21 2023-06-30 13F Amphenol COM 032095101 222,900 0 0.00 18,935 3.95 3.4193
2023-04-13 2023-03-31 13F Amphenol COM 032095101 222,900 142,595 177.57 18,215 197.92 3.4938
2023-01-18 2022-12-31 13F/A-1 Amphenol COM 032095101 80,305 80,305 6,114 1.3773
2023-01-13 2022-12-31 13F Amphenol COM 032095101 80,305 80,305 6 1.3354
2022-10-18 2022-09-30 13F Amphenol COM 032095101 0 -222,120 -100.00 0 -100.00
2022-07-14 2022-06-30 13F Amphenol COM 032095101 222,120 -53,345 -19.37 14,300 -31.10 3.2034
2022-04-18 2022-03-31 13F Amphenol COM 032095101 275,465 0 0.00 20,756 -13.85 3.8614
2022-01-18 2021-12-31 13F Amphenol COM 032095101 275,465 275,465 24,092 4.1707
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.