🕵️ CORE & MAIN, Inc. ($CNM)
SEC insider & ownership activity, last 12 months · CIK 1856525 · every row links its SEC filing
Over the last 12 months insiders sold $6.7M against $195K of open-market buying. Mark R. Witkowski sold $6.4M through a 10b5-1 trading plan in 1 lots (Aug). No red-flag 8-Ks in the window.
Monthly net open-market insider flow, last 12 months (up = net buying)
Insider flow
1 buyer, $195K (2 lots) · 2 sellers, $6.7M (3 lots)
| Insider | Buys | Bought | Sells | Sold | Last |
|---|---|---|---|---|---|
| Mark R. Witkowski | 0 | – | 1 | $6.4M | Aug 18, 2025 |
| Robyn L. Bradbury | 0 | – | 2 | $263K | Apr 17, 2026 |
| James D. Hope | 2 | $195K | 0 | – | Jul 6, 2026 |
5%+ holders
| Holder | Stake | Class | Schedule | Event | |
|---|---|---|---|---|---|
| Blackrock, Inc. | 10.1% | 13G | Apr 7, 2026 | filing ↗ | |
| Capital World Investors | 6.2% | 13G | May 14, 2026 | filing ↗ | |
| Vanguard Capital Management | 5.3% | 13G | Apr 29, 2026 | filing ↗ | |
| Morgan Stanley | 5.2% | 13G | May 5, 2025 | filing ↗ |
Planned insider sales (Form 144)
| Seller | Planned | Approx. sale date | |
|---|---|---|---|
| Mark G. Whittenburg | $2.4M | Jun 30, 2026 | filing ↗ |
| Mark G. Whittenburg | $931K | May 29, 2026 | filing ↗ |
| Mark G. Whittenburg | $1.1M | May 27, 2026 | filing ↗ |
| Stephen O. Leclair | $20.3M | Apr 20, 2026 | filing ↗ |
| Robyn L. Bradbury | $1.8M | Apr 17, 2026 | filing ↗ |
| Stephen O. Leclair | $7.0M | Apr 16, 2026 | filing ↗ |
| Stephen O. Leclair | $16.8M | Apr 15, 2026 | filing ↗ |
| John R. Schaller | $1.1M | Jan 13, 2026 | filing ↗ |
| John R. Schaller | $2.9M | Jan 5, 2026 | filing ↗ |
Material events (8-K)
| Item | Event date | |
|---|---|---|
| Material agreement (1.01) | Jul 1, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jul 1, 2026 | filing ↗ |
| Other events (8.01) | Jun 25, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jun 25, 2026 | filing ↗ |
| Shareholder vote (5.07) | Jun 23, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jun 23, 2026 | filing ↗ |
| Other events (8.01) | Jun 22, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jun 22, 2026 | filing ↗ |
| Earnings (2.02) | Jun 10, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jun 10, 2026 | filing ↗ |
| Other events (8.01) | Apr 9, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Apr 9, 2026 | filing ↗ |
| Officer/director changes (5.02) | Mar 25, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Mar 25, 2026 | filing ↗ |
| Earnings (2.02) | Mar 24, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Mar 24, 2026 | filing ↗ |
| Earnings (2.02) | Dec 9, 2025 | filing ↗ |
| Other events (8.01) | Dec 9, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Dec 9, 2025 | filing ↗ |
| Earnings (2.02) | Sep 9, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Sep 9, 2025 | filing ↗ |
| Officer/director changes (5.02) | Aug 18, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Aug 18, 2025 | filing ↗ |