Brian J. Costanzo
CIK 1873434 · View on SEC EDGAR ↗
First SEC filing: Aug. 23, 2021 · Latest: Aug. 23, 2021
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Insider transactions
Price change vs current quote, split-adjusted for corporate actions since the filing — not benchmarked, not annualized, not size-weighted
No open-market trades on record; showing all filings.
| Date | Ticker | Code | Shares | Price | Value | Owned after | Δ own | A/D | vs now |
|---|---|---|---|---|---|---|---|---|---|
| June 30, 2026 | MKL | J | 2 | $1617.19 | $3,234 | 1,632 Direct | +0.12% | Acquired | 10.9% (price as of 2026-08-21) |
| Dec. 31, 2025 | MKL | J | 2 | $1602.62 | $3,205 | 957 Direct | +0.21% | Acquired | 11.9% (price as of 2026-08-21) |
| Sept. 30, 2025 | MKL | J | 2 | $1624.66 | $3,249 | 976 Direct | +0.21% | Acquired | 10.4% (price as of 2026-08-21) |
| March 31, 2025 | MKL | J | 2 | $1459.76 | $2,920 | 972 Direct | +0.21% | Acquired | 22.9% (price as of 2026-08-21) |
| Feb. 18, 2025 | MKL | A | 379 | — | — | 970 Direct | +64.13% | Acquired | (price as of 2026-08-21) |
| Dec. 31, 2024 | MKL | J | 2 | $1336.81 | $2,674 | 591 Direct | +0.34% | Acquired | 34.2% (price as of 2026-08-21) |
| Dec. 5, 2024 | MKL | F | 21 | $1759.04 | $36,940 | 588 Direct | -3.45% | Disposed | 2.0% (price as of 2026-08-21) |
| Sept. 30, 2024 | MKL | J | 2 | $1333.29 | $2,667 | 609 Direct | +0.33% | Acquired | 34.5% (price as of 2026-08-21) |
| June 28, 2024 | MKL | J | 2 | $1282.46 | $2,565 | 608 Direct | +0.33% | Acquired | 39.9% (price as of 2026-08-21) |
| March 28, 2024 | MKL | J | 2 | $1220.99 | $2,442 | 605 Direct | +0.33% | Acquired | 46.9% (price as of 2026-08-21) |
| Feb. 20, 2024 | MKL | A | 108 | — | — | 604 Direct | +21.77% | Acquired | (price as of 2026-08-21) |
| Feb. 20, 2024 | MKL | A | 94 | — | — | 496 Direct | +23.38% | Acquired | (price as of 2026-08-21) |
| Dec. 29, 2023 | MKL | J | 2 | $1206.92 | $2,414 | 402 Direct | +0.50% | Acquired | 48.6% (price as of 2026-08-21) |
| Dec. 5, 2023 | MKL | F | 15 | $1401.29 | $21,019 | 399 Direct | -3.62% | Disposed | 28.0% (price as of 2026-08-21) |
| Sept. 29, 2023 | MKL | J | 2 | $1164.51 | $2,329 | 414 Direct | +0.49% | Acquired | 54.0% (price as of 2026-08-21) |
| June 30, 2023 | MKL | J | 1 | $1101.99 | $1,102 | 412 Direct | +0.24% | Acquired | 62.8% (price as of 2026-08-21) |
| May 16, 2023 | MKL | A | 29 | — | — | 411 Direct | +7.59% | Acquired | (price as of 2026-08-21) |
| March 31, 2023 | MKL | J | 1 | $1085.80 | $1,086 | 382 Direct | +0.26% | Acquired | 65.2% (price as of 2026-08-21) |
| Feb. 14, 2023 | MKL | A | 54 | — | — | 381 Direct | +16.51% | Acquired | (price as of 2026-08-21) |
| Feb. 15, 2022 | MKL | A | 69 | — | — | 322 Direct | +27.27% | Acquired | (price as of 2026-08-21) |
P = Open-market purchase · S = Sale · A = Grant/award · M = Option exercise · G = Gift · F = Tax withholding
Insider transactions are not a recommendation; sales are often driven by liquidity or tax reasons.
Initial ownership (Form 3) 2 holdings
Securities held when first becoming an insider, per SEC Form 3.
Compensation (DEF 14A)
Matched by name from proxy statements (DEF 14A) — verify against the filing.
MKL
CFO| Fiscal year | Salary | Bonus | Stock awards | Option awards | Non-equity incentive | Pension change | Other | Total |
|---|---|---|---|---|---|---|---|---|
| 2025 | $500,000 | — | $1,335,397 | — | $850,000 | — | $33,910 | — |
| 2024 | $500,000 | — | $649,126 | — | $525,000 | — | $34,100 | — |
| 2023 | $367,181 | — | $175,973 | — | $341,528 | — | $31,256 | — |
Figures from the Summary Compensation Table of the company's proxy statement (DEF 14A). Compensation is not a recommendation.