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MICHAEL OREILLY

CIK 1192729 · Vice Chairman · last filed 2026-06-17

MICHAEL OREILLY is a Vice Chairman who has filed 52 SEC Form 4 insider transactions across 3 companies since 2007. The most recent filing, for MKL, was dated Jun 17, 2026. Across all open-market trades the lifetime net is −$13.1M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $91.2M across reported positions. 28 SEC filings were submitted jointly with MARKEL GROUP INC.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$91.24M

Companies

3

Total Filings

52

Lifetime Open-Market Net

-$13.12M

Filer Profile

Reported Address
15 MOUNTAIN VIEW RD
WARREN, NJ 07059
Related Filers
MARKEL GROUP INC. — 28 joint filings, latest 2026-06-17
Profile details as reported on the filer's SEC submissions — for individual insiders the address is often in care of the issuer. Related filers are identified from jointly filed SEC submissions and shared reported addresses. View filings on SEC EDGAR.

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
MKL Director 3,934 $1784.18 $7.02M $0 25 2026-06-17
ALTERRA CAPITAL HOLDINGS Ltd (ALTE) Delisted Director 24,000 — — $189.8K 4 2012-05-09
CB Vice Chairman 248,999 $338.25 $84.22M -$13.31M 22 2008-05-07

Recent Filings

52 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2026-06-17 MKL Other (J) +89 $150.0K EDGAR
2026-05-22 MKL Grant (A) +89 $0 EDGAR
2025-06-17 MKL Other (J) +80 $140.0K EDGAR
2025-05-23 MKL Grant (A) +88 $0 EDGAR
2024-06-17 MKL Other (J) +100 $140.0K EDGAR
2024-05-23 MKL Grant (A) +100 $0 EDGAR
2023-06-16 MKL Other (J) +116 $140.0K EDGAR
2023-05-18 MKL Grant (A) +122 $0 EDGAR
2022-05-16 MKL Other (J) +117 $140.0K EDGAR
2022-05-13 MKL Grant (A) +129 $0 EDGAR
Showing 1–10 of 52
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Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.