SEC Insider Transactions from Witkowski Mark R.

Last updated: 2026-03-15 09:23 UTC | Total transactions: 38

Mark R. Witkowski, CEO of Core & Main, Inc. ($CNM), sold shares on the open market three times over the past year for a total of $12.5 million. His latest sale occurred on August 18, 2025. These transactions rank 948th among 11,700 insiders by sale value, trailing the average of $8.6 million across 6.4 trades per person. Witkowski made no open market purchases in this period.

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Transaction Date Company Ticker Insider Name Title Transaction Type Security Shares Price Shares Owned Following Total Shares Outstanding % of Owned % of Outstanding
March 12, 2026 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer A Options (Rights to Buy) 131382 $0.00 131,382.0000 198,302,805 9999.99% 0.07%
March 12, 2026 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer A Class A Common Stock 18372 $0.00 51,119.0000 198,302,805 56.10% 0.01%
March 11, 2026 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer F Class A Common Stock 1685 $49.16 32,747.0000 198,302,805 4.89% 0.00%
March 10, 2026 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer F Class A Common Stock 937 $49.38 34,432.0000 198,302,805 2.65% 0.00%
March 9, 2026 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer F Class A Common Stock 478 $49.96 35,369.0000 198,302,805 1.33% 0.00%
Aug. 18, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer C Class A Common Stock 100000 $0.00 135,847.0000 201,442,750 278.96% 0.05%
Aug. 18, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer S Class A Common Stock 100000 $64.08 35,847.0000 201,442,750 73.61% 0.05%
Aug. 18, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer J Class B Common Stock and Limited Partnership Interests 100000 $0.00 616,250.0000 201,442,750 13.96% 0.05%
Aug. 18, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer J Class B Common Stock and Limited Partnership Interests 100000 $0.00 716,250.0000 201,442,750 16.23% 0.05%
Aug. 18, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer C Class B Common Stock and Limited Partnership Interests 100000 $0.00 616,250.0000 201,442,750 13.96% 0.05%
July 17, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer C Class B Common Stock and Limited Partnership Interests 100000 $0.00 716,250.0000 201,442,750 12.25% 0.05%
July 17, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer J Class B Common Stock and Limited Partnership Interests 100000 $0.00 816,250.0000 201,442,750 13.96% 0.05%
July 17, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer J Class B Common Stock and Limited Partnership Interests 100000 $0.00 716,250.0000 201,442,750 12.25% 0.05%
July 17, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer S Class A Common Stock 27669 $61.63 35,847.0000 201,442,750 43.56% 0.01%
July 17, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer S Class A Common Stock 72331 $61.12 63,516.0000 201,442,750 53.24% 0.04%
July 17, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer C Class A Common Stock 100000 $0.00 135,847.0000 201,442,750 278.96% 0.05%
March 31, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer A Options (Rights to Buy) 73458 $0.00 73,458.0000 201,442,750 9999.99% 0.04%
March 31, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Executive Officer A Class A Common Stock 10092 $0.00 35,847.0000 201,442,750 39.18% 0.01%
March 13, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer A Options (Rights to Buy) 53094 $0.00 53,094.0000 201,442,750 9999.99% 0.03%
March 13, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer A Class A Common Stock 7296 $0.00 25,755.0000 201,442,750 39.53% 0.00%
March 11, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer F Class A Common Stock 925 $46.55 18,459.0000 201,442,750 4.77% 0.00%
March 7, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer F Class A Common Stock 536 $47.87 20,380.0000 201,442,750 2.56% 0.00%
March 10, 2025 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer F Class A Common Stock 996 $46.69 19,384.0000 201,442,750 4.89% 0.00%
March 13, 2023 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer F Class A Common Stock 1054 $21.45 22,844.0000 246,217,004 4.41% 0.00%
March 11, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer F Class A Common Stock 999 $48.29 21,845.0000 227,818,077 4.37% 0.00%
March 11, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer F Class A Common Stock 929 $48.29 20,916.0000 227,818,077 4.25% 0.00%
May 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer J Class B Common Stock and Limited Partnership Interests 50000 $0.00 816,250.0000 227,818,077 5.77% 0.02%
May 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer J Class B Common Stock and Limited Partnership Interests 50000 $0.00 866,250.0000 227,818,077 6.13% 0.02%
May 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer C Class B Common Stock and Limited Partnership Interests 50000 $0.00 816,250.0000 227,818,077 5.77% 0.02%
May 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer S Class A Common Stock 50000 $59.50 23,898.0000 227,818,077 67.66% 0.02%
May 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer C Class A Common Stock 50000 $0.00 73,898.0000 227,818,077 209.22% 0.02%
April 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer C Class A Common Stock 50000 $0.00 73,898.0000 227,818,077 209.22% 0.02%
April 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer J Class B Common Stock and Limited Partnership Interests 50000 $0.00 916,250.0000 227,818,077 5.77% 0.02%
April 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer C Class B Common Stock and Limited Partnership Interests 50000 $0.00 866,250.0000 227,818,077 5.46% 0.02%
April 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer S Class A Common Stock 50000 $58.51 23,898.0000 227,818,077 67.66% 0.02%
April 8, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer J Class B Common Stock and Limited Partnership Interests 50000 $0.00 866,250.0000 227,818,077 5.46% 0.02%
March 7, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer A Options (Rights to Buy) 36726 $0.00 36,726.0000 227,818,077 9999.99% 0.02%
March 7, 2024 Core & Main, Inc. $CNM Witkowski Mark R Chief Financial Officer A Class A Common Stock 4677 $0.00 23,898.0000 227,818,077 24.33% 0.00%