Brian J. Costanzo serves as Executive at MARKEL CORP, where they oversee executive responsibilities. Since joining the company, Brian J. Costanzo has executed 17 insider transactions totaling $0, demonstrating a balanced approach to their equity position. Their most recent transaction on Feb 24, 2026 involved receiving (via award) 654.64 shares valued at $0.
Brian J. Costanzo currently holds 1,611.18 shares of MARKEL CORP (MKL), valued at approximately $0. This represents their equity stake as Executive.
Based on SEC Form 4 filings, Brian J. Costanzo has been a net neutral trader of MKL stock. They have purchased $0 and sold $0 worth of shares.
Brian J. Costanzo's most recent insider trade was on Feb 24, 2026, when they sold 654.64 shares at $0.00 per share.
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| $1602.62 |
| Discretionary |
| Dec 2, 2025 | MKL | $44.8K | Payment | 21.72 | $2060.83 | Discretionary |
| Sep 30, 2025 | MKL | $3.0K | Other | 1.85 | $1624.66 | Discretionary |
| Jun 30, 2025 | MKL | $3.5K | Other | 2.21 | $1580.87 | Discretionary |
| Jun 28, 2024 | MKL | $2.8K | Other | 2.18 | $1282.46 | Discretionary |
| Mar 28, 2024 | MKL | $2.4K | Other | 1.97 | $1220.99 | Discretionary |
| Feb 20, 2024 | MKL | $0 | Award | 94 | $N/A | Discretionary |
| Feb 20, 2024 | MKL | $0 | Award | 108 | $N/A | Discretionary |
| Dec 29, 2023 | MKL | $2.8K | Other | 2.32 | $1206.92 | Discretionary |
| Dec 5, 2023 | MKL | $21.0K | Payment | 15 | $1401.29 | Discretionary |
| Sep 29, 2023 | MKL | $2.4K | Other | 2.06 | $1164.51 | Discretionary |
| Jun 30, 2023 | MKL | $1.5K | Other | 1.37 | $1101.99 | Discretionary |
| May 16, 2023 | MKL | $0 | Award | 29 | $N/A | Discretionary |
| Mar 31, 2023 | MKL | $1.3K | Other | 1.19 | $1085.80 | Discretionary |
| Feb 14, 2023 | MKL | $0 | Award | 54 | $N/A | Discretionary |
| Feb 15, 2022 | MKL | $0 | Award | 69 | $N/A | Discretionary |