Summary
Updated Aug 31, 2026
George Manning Rountree is Chief Executive Officer, Director of WHITE MOUNTAINS INSURANCE GROUP LTD (WTM). 1 SEC Form 4 filing on record, dated 22 December 2025. Most recent open-market trade: sold $10.25M of WTM on 22 December 2025. Lifetime open-market sales: $10.25M.
Recent Transactions
1Every recent SEC Form 4 transaction George Manning Rountree has reported, most recent first.
Trading Pattern
InsiderAlpha's records for George Manning Rountree go back to 2025: 1 primary Form 4 filing, an average of 0.5 per year. No transaction on record carries a Rule 10b5-1 flag - the filings look discretionary rather than pre-scheduled, which makes their timing more informative as a signal.
Other Insiders Active in the Same Stocks
Insiders who reported open-market trades in the last 12 months at the companies George Manning Rountree files at. Multiple unrelated insiders buying the same stock within a short window, cluster buying, has historically been one of the strongest Form 4 signals.
- Philip A. Gelston - $338K of WTM open-market activity in the last 12 months
- Reid Tarlton Campbell - of WTM open-market activity in the last 12 months
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
Frequently Asked Questions
Who is George Manning Rountree?
George Manning Rountree is a corporate insider, tracked as Chief Executive Officer, Director of WHITE MOUNTAINS INSURANCE GROUP LTD (WTM). InsiderAlpha holds 1 primary Form 4 filing for them, the earliest from 2025, updated as new SEC EDGAR filings are processed.
When did George Manning Rountree last file a Form 4?
The only primary Form 4 on record is dated 22 December 2025.
Has George Manning Rountree been buying or selling stock?
Recorded transactions: 0 open-market purchases and 1 open-market sale ($10.25M) across all tracked filings.
Where can I see all of George Manning Rountree's SEC filings?
All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.
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