Core & Main, Inc.
US ˙ NYSE ˙ US21874C1027

SecurityCNM / Core & Main, Inc.
InstitutionJanus Henderson Group Plc
Latest Disclosed Ownership3,377,281 shares
Latest Disclosed Value $ 166,867,185
Janus Henderson Group Plc reports 26.96% decrease in ownership of CNM / Core & Main, Inc.

On May 18, 2026 - Janus Henderson Group Plc filed a 13F-HR/A form disclosing ownership of 3,377,281 shares of Core & Main, Inc. (US:CNM) valued at $166,837,681 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 4,623,727 shares of Core & Main, Inc.. This represents a change in shares of -26.96% during the quarter. The current value of the position is $175,517,294 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)
2026-05-18 2026-03-31 13F/A-1 CORE & MAIN CL A 21874C102 3,377,281 -1,246,446 -26.96 166,867 -30.55 0.0797
2026-05-15 2026-03-31 13F CORE & MAIN CL A 21874C102 3,377,281 -1,246,446 166,867 0.0310
2026-02-17 2025-12-31 13F CORE & MAIN CL A 21874C102 4,623,727 -534,309 -10.36 240,273 -13.46 0.1076
2025-11-14 2025-09-30 13F CORE & MAIN CL A 21874C102 5,158,036 317,453 6.56 277,657 -4.96 0.1268
2025-08-14 2025-06-30 13F CORE & MAIN CL A 21874C102 4,840,583 -4,691 -0.10 292,139 24.34 0.1432
2025-05-15 2025-03-31 13F CORE & MAIN CL A 21874C102 4,845,274 -85,622 -1.74 234,945 -6.39 0.1288
2025-02-14 2024-12-31 13F CORE & MAIN CL A 21874C102 4,930,896 -84,971 -1.69 250,992 12.69 0.1276
2024-11-14 2024-09-30 13F CORE & MAIN CL A 21874C102 5,015,867 -27,862 -0.55 222,733 -9.75 0.1140
2024-08-14 2024-06-30 13F CORE & MAIN CL A 21874C102 5,043,729 -161,999 -3.11 246,802 -17.18 0.1322
2024-05-15 2024-03-31 13F CORE & MAIN CL A 21874C102 5,205,728 -913,401 -14.93 297,995 20.52 0.1626
2024-02-14 2023-12-31 13F CORE & MAIN CL A 21874C102 6,119,129 969,599 18.83 247,265 66.43 0.1475
2023-11-14 2023-09-30 13F CORE & MAIN CL A 21874C102 5,149,530 -614,754 -10.66 148,567 -17.76 0.0973
2023-08-14 2023-06-30 13F CORE & MAIN CL A 21874C102 5,764,284 -2,080,354 -26.52 180,647 -0.31 0.1123
2023-05-15 2023-03-31 13F CORE & MAIN CL A 21874C102 7,844,638 31,789 0.41 181,208 20.11 0.1195
2023-02-14 2022-12-31 13F CORE & MAIN CL A 21874C102 7,812,849 -59,285 -0.75 150,868 -15.72 0.1078
2023-01-13 2022-09-30 13F/A-1 CORE & MAIN CL A 21874C102 7,872,134 1,215,618 18.26 179,011 20.60 0.1341
2022-11-14 2022-09-30 13F CORE & MAIN CL A 21874C102 7,872,134 1,215,618 179,011 0.1340
2022-08-15 2022-06-30 13F CORE & MAIN CL A 21874C102 6,656,516 -28,251 -0.42 148,437 -8.20 0.1024
2022-05-16 2022-03-31 13F CORE & MAIN CL A 21874C102 6,684,767 1,365,400 25.67 161,702 0.19 0.0781
2022-02-14 2021-12-31 13F CORE & MAIN CL A 21874C102 5,319,367 -53,944 -1.00 161,391 14.60 0.0673
2021-11-16 2021-09-30 13F CORE & MAIN CL A 21874C102 5,373,311 5,373,311 140,826 0.0616
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.