Comparable stake leader
BlackRock, Inc.
SEC ownership of Core & Main, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001856525.
Disclosed value leader
BlackRock, Inc.
Comparable rows
50/50
Latest evidence
07 Apr 2026
- Symbol
- CNM on NYSE
- SEC evidence covered
- 13F, 13D/G, and 3/4/5
- Largest SEC-reported holder
- BlackRock, Inc.
- Latest 13D/G holder
- BlackRock, Inc.
- Latest parsed evidence date
- 07 Apr 2026
- CIK
- 0001856525
- Location
- St. Louis, MO
Ownership snapshot
2 signals
Issuer
2 identity fields
Ownership snapshot
Top shareholders of Core & Main, Inc. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
BlackRock, Inc.
Disclosed value leader
BlackRock, Inc.
Comparable rows
50/50
Latest evidence
07 Apr 2026
13F
13D/G
3/4/5
Lead comparable stake: 10%
13D/G row: BlackRock, Inc.
Showing 1-8 of 50 holder rows.
Quick read
BlackRock, Inc. leads the comparable SEC ownership view at 10%.
50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Comparable ownership
Top 5
BlackRock, Inc.
10%
Select Equity Group, L.P.
4.1%
MORGAN STANLEY
2.7%
Bhavani Amirthalingam
0.01%
Kathleen M. Mazzarella
0.01%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| BlackRock, Inc. |
13F
13D/G
Company
|
10%
from 13D/G
|
$948,777,609
19,206,024 shares
|
— | 31 Mar 2026 |
| Select Equity Group, L.P. |
13D/G
13F
Company
|
4.1%
|
$440,489,433
7,778,376 shares
|
-$108,397,182 | 31 Dec 2025 |
| MORGAN STANLEY |
13F
13D/G
Company
|
2.7%
from 13D/G
|
$268,522,771
5,435,680 shares
|
— | 31 Mar 2026 |
| Bhavani Amirthalingam |
3/4/5
Director
|
0.01%
|
$806,753
15,156 shares
|
— | 24 Jun 2025 |
| Kathleen M. Mazzarella |
3/4/5
Director
|
0.01%
|
$747,348
14,040 shares
|
— | 24 Jun 2025 |
| Robert M. Buck |
3/4/5
Director
|
0.01%
|
$694,651
13,050 shares
|
— | 24 Jun 2025 |
| James D. Hope |
3/4/5
Director
|
0%
|
$351,772
6,939 shares
|
+$99,971 | 07 Apr 2026 |
| Jackie M. Burkhardt |
3/4/5
General Counsel and CCO
|
0%
|
$314,470
6,051 shares
|
— | 01 Apr 2026 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to selling over the last 12 months. Net value: -$32,078,213.
Buys
$99,971
Insiders: 1
Sells
$32,178,183
Insiders: 7
Net
-$32,078,213
Shares: -521,679
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 1,972
Shares: 523,651
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 1,972 | 5,000 | $99,971 | $262,724 | -$162,754 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 518,651 | $0 | $31,915,459 | -$31,915,459 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 26 reporting-owner rows connected to Core & Main, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
26
Largest Forms 3/4/5 holder
Mark G. Whittenburg
Net 12M change
-$29,507,918
Latest report
17 Apr 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Mark G. Whittenburg | General Counsel and Secretary | $16,872,241 | -$3,001,255 | -15% | Mixed | 11 Mar 2026 |
| Dennis G. Gipson | Director | $12,399,910 | Mixed | 24 Jun 2025 | ||
| John W. Stephens | Chief Accounting Officer | $6,693,803 | Mixed | 11 Mar 2026 | ||
| LeClair Stephen O | Executive Chair, Director | $3,868,956 | -$7,767,601 | -67% | Mixed | 09 Mar 2026 |
| Mark R. Witkowski | Chief Executive Officer, Director | $2,990,461 | -$12,534,598 | -81% | Mixed | 11 Mar 2026 |
| Margaret M. Newman | Director | $2,964,563 | Mixed | 24 Jun 2025 | ||
| Bradford A. Cowles | President | $1,491,223 | Mixed | 11 Mar 2026 | ||
| Michael G. Huebert | President | $1,482,214 | Mixed | 11 Mar 2026 | ||
| John R. Schaller | Executive Vice President | $1,082,895 | Filing P/S | 28 May 2025 | ||
| Orvin T. Kimbrough | Director | $862,344 | -$1,480,094 | -63% | Mixed | 18 Jul 2025 |
| Carla D. Harper | Senior VP, Human Resources | $811,629 | Mixed | 11 Mar 2026 | ||
| Bhavani Amirthalingam | Director | $806,753 | Mixed | 24 Jun 2025 | ||
| Kathleen M. Mazzarella | Director | $747,348 | Mixed | 24 Jun 2025 | ||
| Laura K. Schneider | Chief Human Resources Officer | $724,092 | Filing P/S | 03 Jun 2025 | ||
| Robert M. Buck | Director | $694,651 | Mixed | 24 Jun 2025 | ||
| Robyn L. Bradbury | Chief Financial Officer | $661,607 | -$2,097,558 | -76% | Mixed | 17 Apr 2026 |
| Jeffrey D. Giles | EVP, Corporate Development | $566,338 | Mixed | 12 Mar 2026 | ||
| James D. Hope | Director | $351,772 | +$99,971 | +40% | Filing P/S | 07 Apr 2026 |
| Jackie M. Burkhardt | General Counsel and CCO | $314,470 | Mixed | 01 Apr 2026 | ||
| James G. Castellano | Director | $279,903 | -$2,726,783 | -91% | Mixed | 18 Jul 2025 |
Recent insider transactions for Core & Main, Inc.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Robyn L. Bradbury | CNM | Class A Common Stock | Sale | -28.6% | $262,724 | $52.54 | -5,000 | 12,500 | 17 Apr 2026 | Direct |
| Robyn L. Bradbury | CNM | Class A Common Stock | Conversion of derivative security | 40% | 5,000 | 17,500 | 17 Apr 2026 | Direct | ||
| Robyn L. Bradbury | CNM | Class B Common Stock and Limited Partnership Interests | Conversion of derivative security | -100% | -5,000 | 0 | 17 Apr 2026 | Direct | ||
| Robyn L. Bradbury | CNM | Class B Common Stock and Limited Partnership Interests | Other | 5,000 | 5,000 | 17 Apr 2026 | Direct | |||
| Robyn L. Bradbury | CNM | Class B Common Stock and Limited Partnership Interests | Other | -3.18% | -5,000 | 152,447 | 17 Apr 2026 | By LLC | ||
| James D. Hope | CNM | Class A Common Stock | Purchase | 39.7% | $99,971 | $50.70 | 1,972 | 6,939 | 07 Apr 2026 | Direct |
| M. Susan Hardwick | CNM | Class A Common Stock | Award | 580 | 580 | 01 Apr 2026 | Direct | |||
| Jeffrey D. Giles | CNM | Class A Common Stock | Award | 45.4% | 3,021 | 9,681 | 12 Mar 2026 | Direct | ||
| Jeffrey D. Giles | CNM | Options (Rights to Buy) | Award | 21,585 | 21,585 | 12 Mar 2026 | Direct | |||
| Robyn L. Bradbury | CNM | Class A Common Stock | Award | 62.8% | 4,824 | 12,500 | 12 Mar 2026 | Direct | ||
| Robyn L. Bradbury | CNM | Options (Rights to Buy) | Award | 34,488 | 34,488 | 12 Mar 2026 | Direct | |||
| Mark R. Witkowski | CNM | Class A Common Stock | Award | 56.1% | 18,372 | 51,119 | 12 Mar 2026 | Direct | ||
| Mark R. Witkowski | CNM | Options (Rights to Buy) | Award | 131,382 | 131,382 | 12 Mar 2026 | Direct | |||
| Bradford A. Cowles | CNM | Class A Common Stock | Award | 38.5% | 7,086 | 25,491 | 12 Mar 2026 | Direct | ||
| Bradford A. Cowles | CNM | Options (Rights to Buy) | Award | 50,676 | 50,676 | 12 Mar 2026 | Direct | |||
| John W. Stephens | CNM | Class A Common Stock | Award | 5.69% | 936 | 17,374 | 12 Mar 2026 | Direct | ||
| John W. Stephens | CNM | Options (Rights to Buy) | Award | 6,684 | 6,684 | 12 Mar 2026 | Direct | |||
| Michael G. Huebert | CNM | Class A Common Stock | Award | 70.8% | 10,500 | 25,337 | 12 Mar 2026 | Direct | ||
| Michael G. Huebert | CNM | Options (Rights to Buy) | Award | 37,539 | 37,539 | 12 Mar 2026 | Direct | |||
| Carla D. Harper | CNM | Class A Common Stock | Award | 21.6% | 2,463 | 13,874 | 12 Mar 2026 | Direct | ||
| Carla D. Harper | CNM | Options (Rights to Buy) | Award | 17,598 | 17,598 | 12 Mar 2026 | Direct | |||
| Mark G. Whittenburg | CNM | Class A Common Stock | Tax liability | -3.74% | -331 | 8,525 | 11 Mar 2026 | Direct | ||
| Robyn L. Bradbury | CNM | Class A Common Stock | Tax liability | -5% | -404 | 7,676 | 11 Mar 2026 | Direct | ||
| Mark R. Witkowski | CNM | Class A Common Stock | Tax liability | -4.89% | -1,685 | 32,747 | 11 Mar 2026 | Direct | ||
| Bradford A. Cowles | CNM | Class A Common Stock | Tax liability | -3.19% | -607 | 18,405 | 11 Mar 2026 | Direct | ||
| John W. Stephens | CNM | Class A Common Stock | Tax liability | -0.65% | -107 | 16,438 | 11 Mar 2026 | Direct | ||
| Michael G. Huebert | CNM | Class A Common Stock | Tax liability | -2.92% | -447 | 14,837 | 11 Mar 2026 | Direct | ||
| Carla D. Harper | CNM | Class A Common Stock | Tax liability | -0.77% | -89 | 11,411 | 11 Mar 2026 | Direct | ||
| Mark G. Whittenburg | CNM | Class A Common Stock | Tax liability | -5.92% | -557 | 8,856 | 10 Mar 2026 | Direct | ||
| Carla D. Harper | CNM | Class A Common Stock | Tax liability | -1.62% | -189 | 11,500 | 10 Mar 2026 | Direct | ||
| John W. Stephens | CNM | Class A Common Stock | Tax liability | -1.18% | -198 | 16,545 | 10 Mar 2026 | Direct | ||
| Bradford A. Cowles | CNM | Class A Common Stock | Tax liability | -3.75% | -741 | 19,012 | 10 Mar 2026 | Direct | ||
| Mark R. Witkowski | CNM | Class A Common Stock | Tax liability | -2.65% | -937 | 34,432 | 10 Mar 2026 | Direct | ||
| Stephen O LeClair | CNM | Class A Common Stock | Tax liability | -4.45% | -3,081 | 66,136 | 10 Mar 2026 | Direct | ||
| Robyn L. Bradbury | CNM | Class A Common Stock | Tax liability | -2.47% | -205 | 8,080 | 10 Mar 2026 | Direct | ||
| Mark G. Whittenburg | CNM | Class A Common Stock | Tax liability | -2.87% | -278 | 9,413 | 09 Mar 2026 | Direct | ||
| Carla D. Harper | CNM | Class A Common Stock | Tax liability | -0.65% | -77 | 11,689 | 09 Mar 2026 | Direct | ||
| John W. Stephens | CNM | Class A Common Stock | Tax liability | -0.56% | -94 | 16,743 | 09 Mar 2026 | Direct | ||
| Michael G. Huebert | CNM | Class A Common Stock | Tax liability | -2.24% | -350 | 15,284 | 09 Mar 2026 | Direct | ||
| Bradford A. Cowles | CNM | Class A Common Stock | Tax liability | -2.15% | -435 | 19,753 | 09 Mar 2026 | Direct | ||
| Mark R. Witkowski | CNM | Class A Common Stock | Tax liability | -1.33% | -478 | 35,369 | 09 Mar 2026 | Direct | ||
| Stephen O LeClair | CNM | Class A Common Stock | Tax liability | -2.15% | -1,519 | 69,217 | 09 Mar 2026 | Direct | ||
| Robyn L. Bradbury | CNM | Class A Common Stock | Tax liability | -3.16% | -270 | 8,285 | 09 Mar 2026 | Direct | ||
| Jeffrey D. Giles | CNM | Class A Common Stock | Award | 191.7% | 4,377 | 6,660 | 26 Jan 2026 | Direct | ||
| Jeffrey D. Giles | CNM | Options (Rights to Buy) | Award | 10,617 | 10,617 | 26 Jan 2026 | Direct | |||
| Mark G. Whittenburg | CNM | Class B Common Stock and Limited Partnership Interests | Gift | -10.1% | -25,500 | 227,312 | 31 Dec 2025 | By LLC | ||
| John W. Stephens | CNM | Class A Common Stock | Options Exercise | 308.7% | 12,717 | 16,837 | 12 Sep 2025 | Direct | ||
| John W. Stephens | CNM | Options (Rights to Buy) | Options Exercise | -100% | -12,717 | 0 | 12 Sep 2025 | Direct | ||
| Carla D. Harper | CNM | Class A Common Stock | Award | 21.6% | 2,091 | 11,766 | 03 Sep 2025 | Direct | ||
| Mark R. Witkowski | CNM | Class A Common Stock | Sale | -73.6% | $6,408,210 | $64.08 | -100,000 | 35,847 | 18 Aug 2025 | Direct |
* marks a reported price that did not pass the local price check.