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REID TARLTON CAMPBELL

CIK 1378156 · President · last filed 2026-05-22

REID TARLTON CAMPBELL is a President who has filed 50 SEC Form 4 insider transactions across 1 company since 2007. The most recent filing, for WTM, was dated May 22, 2026. Across all open-market trades the lifetime net is −$14.7M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $22.5M across reported positions. 51 SEC filings were submitted jointly with WHITE MOUNTAINS INSURANCE GROUP LTD.

"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

$22.49M

Companies

1

Total Filings

50

Lifetime Open-Market Net

-$14.67M

Filer Profile

Reported Address
C/O WHITE MOUNTAINS INSURANCE GROUP
80 SOUTH MAIN STREET
HANOVER, NH 03755
Related Filers
WHITE MOUNTAINS INSURANCE GROUP LTD — 51 joint filings, latest 2026-05-22
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
WTM Director 10,694 $2103.49 $22.49M -$14.67M 50 2026-05-22

Recent Filings

50 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
2026-05-22 WTM Grant (A) +135 $0 EDGAR
2025-12-22 WTM Sell (S) −5,000 $0 EDGAR
2025-12-22 WTM Sell (S) −5,000 -$10.25M EDGAR
2025-11-26 WTM Gift (G) −50 $0 EDGAR
2025-05-23 WTM Grant (A) +150 $0 EDGAR
2024-05-24 WTM Grant (A) +165 $0 EDGAR
2024-03-21 WTM Gift (G) −55 $0 EDGAR
2024-02-23 WTM Grant (A) +45 $0 EDGAR
2024-01-02 WTM Tax (F) −710 -$1.07M EDGAR
2023-01-03 WTM Tax (F) −710 -$1.00M EDGAR
Showing 1–10 of 50
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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.