| Insider | Role | Shares | Value | Buys | Sells |
|---|---|---|---|---|---|
| Date | Ticker | Insider | Role | Type | Shares | Price | Value | Chg% | SEC |
|---|---|---|---|---|---|---|---|---|---|
| Insider | Role | Shares | Value | Buys | Sells |
|---|---|---|---|---|---|
| Date | Ticker | Insider | Role | Type | Shares | Price | Value | Chg% | SEC |
|---|---|---|---|---|---|---|---|---|---|
Chief Executive Officer | Chief Financial Officer
1 company
Mark R Witkowski is Chief Executive Officer at CNM. Mark R Witkowski's net worth is not public. Form 4 filings only show shares in the companies where this person is an insider; those holdings are worth an estimated $1.4M at current prices.
Our model assigns Mark R Witkowski a middling insider score of 54/100, based on 8 past trades. Over a 12-month horizon, 50.0% of those trades were profitable, with an average 12-month return of -7.8%.
The CNM filings lean toward selling, a net 420,000 shares.
Mark R Witkowski has 19 Form 4 filings on record from March 2022 to October 2026, all as Chief Executive Officer at Core & Main (CNM), 2022–2026.
The 57 reported transactions were 18 other transactions, 9 tax withholdings, 9 open-market sales and 8 conversions, plus smaller numbers of other types.
Counted by filing, the open-market trades come to no purchases and 8 sales worth about $22.2M.
The largest open-market sale was 100,000 shares of CNM at an average $64.08 on August 18, 2025, about $6.4M. Twelve months later CNM was down 30%.
All 8 sales since April 2023 were made under a Rule 10b5-1 trading plan, set up in advance.
| Date | Ticker | Role | Type | Shares | Price | Value | Chg% | 3M | 12M | SEC |
|---|---|---|---|---|---|---|---|---|---|---|
| Aug 18, 2025 | CNM Core & Main, Inc. | Chief Executive Officer | Sell10b5-1 | 100,000 | $64.08 | $6,408,210.00 | -73.6% | -30.7% | -29.9% | |
| Jul 17, 2025 | CNM Core & Main, Inc. | Chief Executive Officer | Sell10b5-1 | 100,000 | $61.26 | $6,126,387.75 | -73.6% | -16.0% | -26.9% | |
| May 8, 2024 | CNM Core & Main, Inc. | Chief Financial Officer | Sell10b5-1 | 50,000 | $59.50 | $2,975,005.00 | -67.7% | -20.3% | -13.0% | |
| Apr 8, 2024 | CNM Core & Main, Inc. | Chief Financial Officer | Sell10b5-1 | 50,000 | $58.51 | $2,925,730.00 | -67.7% | -15.2% | -24.0% | |
| Nov 15, 2023 | CNM Core & Main, Inc. | Chief Financial Officer | Sell10b5-1 | 40,000 | $34.01 | $1,360,480.00 | -67.5% | +28.3% | +23.4% | |
| Nov 9, 2023 | CNM Core & Main, Inc. | Chief Financial Officer | Sell10b5-1 | 20,000 | $32.10 | $642,022.00 | -51.0% | +33.0% | +37.3% | |
| Oct 4, 2023 | CNM Core & Main, Inc. | Chief Financial Officer | Sell10b5-1 | 20,000 | $30.02 | $600,330.00 | -51.0% | +31.4% | +41.0% | |
| Sep 25, 2023 | CNM Core & Main, Inc. | Chief Financial Officer | Sell10b5-1 | 40,000 | $28.44 | $1,137,740.00 | -67.5% | +39.6% | +54.0% |