According to recent filings covering the 90 days ending February 10, 2026, the three most significant insider holders at Core & Main are Executive Chair Stephen O Leclair (70.74K shares), Chief Executive Officer Mark R Witkowski (35.85K shares), President Bradford A Cowles (20.19K shares).
| Holder | Position | Shares | Report Date |
|---|---|---|---|
| Stephen O Leclair | Executive Chair | 70,736 | 08 Jul, 2025 |
| Mark R Witkowski | Chief Executive Officer | 35,847 | 20 Aug, 2025 |
| Bradford A Cowles | President | 20,188 | 17 Mar, 2025 |
| John R Schaller | Executive Vice President | 19,689 | 30 May, 2025 |
| John Weldon Stephens | Chief Accounting Officer | 16,837 | 16 Sep, 2025 |
| Michael G. Huebert | President | 15,634 | 23 Jul, 2025 |
| Bhavani Amirthalingam | 15,156 | 26 Jun, 2025 | |
| Orvin T Kimbrough | 13,961 | 21 Jul, 2025 | |
| Margaret Newman | 13,958 | 26 Jun, 2025 | |
| Dennis G Gipson | 13,958 | 26 Jun, 2025 | |
| Kathleen M Mazzarella | 13,958 | 26 Jun, 2025 | |
| Robert M Buck | 13,050 | 26 Jun, 2025 | |
| Laura K Schneider | Chief Human Resources Officer | 12,873 | 05 Jun, 2025 |
| Carla D Harper | Senior Vp And Human Resources | 11,766 | 05 Sep, 2025 |
| Mark G Whittenburg | General Counsel And Secretary | 9,691 | 10 Jun, 2025 |
| Robyn L Bradbury | Chief Financial Officer | 8,577 | 23 Jul, 2025 |
| Jeffrey D Giles | Evp And Corporate Development | 6,660 | 28 Jan, 2026 |
| James D Hope | 4,967 | 26 Jun, 2025 | |
| James G Castellano | 4,638 | 26 Jun, 2025 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 26 Jan, 2026 | Jeffrey D Giles | Class A Common Stock | A | 4,377 | $0.00 | 6,660 | D | A |
| 12 Sep, 2025 | John Weldon Stephens | Class A Common Stock | A | 12,717 | $20.81 | 16,837 | D | M |
| 12 Sep, 2025 | John Weldon Stephens | - | - | 16,837 | D | |||
| 03 Sep, 2025 | Carla D Harper | - | - | 11,766 | D | |||
| 03 Sep, 2025 | Carla D Harper | Class A Common Stock | A | 2,091 | $0.00 | 11,766 | D | A |
| 18 Aug, 2025 | Mark R Witkowski | Class A Common Stock | D | 100,000 | $64.08 | 35,847 | D | S |
| 18 Aug, 2025 | Mark R Witkowski | Class A Common Stock | A | 100,000 | $0.00 | 135,847 | D | C |
| 22 Jul, 2025 | Michael G. Huebert | Class A Common Stock | D | 1,337 | $65.03 | 15,634 | D | F |
| 22 Jul, 2025 | Robyn L Bradbury | Class A Common Stock | D | 5,000 | $64.51 | 8,555 | D | S |
| 22 Jul, 2025 | Robyn L Bradbury | Class A Common Stock | A | 5,000 | $0.00 | 13,555 | D | C |
| 22 Jul, 2025 | Robyn L Bradbury | - | - | 13,555 | D | |||
| 18 Jul, 2025 | James G Castellano | - | - | 43,994 | I | |||
| 18 Jul, 2025 | James G Castellano | Class A Common Stock | A | 34,674 | $0.00 | 43,994 | I | C |
| 18 Jul, 2025 | James G Castellano | Class A Common Stock | D | 43,994 | $61.98 | 0 | I | S |
| 18 Jul, 2025 | James G Castellano | - | - | 0 | I | |||
| 18 Jul, 2025 | Orvin T Kimbrough | Class A Common Stock | A | 5 | $0.00 | 13,963 | D | J |
| 18 Jul, 2025 | Orvin T Kimbrough | Class A Common Stock | D | 5 | $0.00 | 3 | I | J |
| 18 Jul, 2025 | Orvin T Kimbrough | Class A Common Stock | A | 23,957 | $0.00 | 37,920 | D | C |
| 18 Jul, 2025 | Orvin T Kimbrough | - | - | 13,958 | D | |||
| 18 Jul, 2025 | Orvin T Kimbrough | - | - | 37,920 | D |