Amphenol Corporation
US ˙ NYSE ˙ US0320951017

SecurityAPH / Amphenol Corporation
InstitutionJ. Stern & Co. LLP
Latest Disclosed Ownership499,402 shares
Latest Disclosed Value $ 63,099,443
J. Stern & Co. LLP reports 99.35% decrease in ownership of APH / Amphenol Corporation

On May 15, 2026 - J. Stern & Co. LLP filed a 13F-HR form disclosing ownership of 499,402 shares of Amphenol Corporation (US:APH) valued at $63,099,443 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on February 24, 2026 disclosing 76,769,791 shares of Amphenol Corporation. This represents a change in shares of -99.35% during the quarter. The current value of the position is $69,321,992 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)
2026-05-15 2026-03-31 13F AMPHENOL CL A 032095101 499,402 -76,270,389 -99.35 63,099 -17.81 6.1168
2026-02-24 2025-12-31 13F/A-1 Amphenol CL A 032095101 76,769,791 75,964,718 9,435.76 76,770 -22.94 6.5427
2026-02-17 2025-12-31 13F Amphenol CL A 032095101 76,769,791 75,964,718 76,770 6.5427
2025-11-14 2025-09-30 13F Amphenol Class A 032095101 805,073 -66,736 -7.65 99,628 27.38 7.5385
2025-08-14 2025-06-30 13F Amphenol Class A 032095101 871,809 26,690 3.16 78,212 41.10 6.6810
2025-05-14 2025-03-31 13F Amphenol COM 032095101 845,119 71,421 9.23 55,431 3.16 5.3118
2025-02-14 2024-12-31 13F Amphenol CL A 032095101 773,698 24,446 3.26 53,733 10.06 5.0610
2024-11-13 2024-09-30 13F Amphenol Corp CL A 032095101 749,252 35,339 4.95 48,821 1.51 5.2028
2024-08-14 2024-06-30 13F AMPHENOL CORP CL A 032095101 713,913 320,224 81.34 48,096 5.91 5.7264
2024-05-15 2024-03-31 13F Amphenol Corp Class A 032095101 393,689 75,678 23.80 45,412 41.25 5.7427
2024-02-22 2023-12-31 13F/A-1 AMPHENOL CORP CL A 032095101 318,011 318,011 32,151 5.8555
2024-02-13 2023-12-31 13F Amphenol Corp CL A 032095101 318,011 318,011 32,151 5.8555
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.