WHITE MOUNTAINS INSURANCE GROUP LTD
WTM · Fire, Marine & Casualty Insurance · 2.5M shares · -5%/yr ↓ buyback · EDGAR filings ↗
Net buyback after stock comp: $17M (gross $33M, SBC $15M)
Reference price $2,050.00 · est. market cap ~$5.1B — last insider sale, 2025-12-19 (estimated from the dated SEC Form 4 price × shares outstanding — not a live quote)
Grade
B80White Mountains Insurance — disciplined insurance/investment holding company.
Strengths
- ROE 20.4% (74th pct), ROA (93rd)
- High net margin (83rd), low leverage (33rd)
- Skilled capital allocation
Risks
- Lumpy, investment-driven results
- Holding-co complexity
- Reinvestment-timing risk
Notable findings
- Exec changeRecent 8-K item 5.02 8-K ↗
- Buying back stockNet buyback — share count -5%/yr over 4y
- Revenue declineRevenue -67.7% YoY
Quarterly revenue
Last 4 quarters · from SEC filings.
Key metrics
Gross margin
95.9%
Net margin
29.6%
Return on equity
20.4%
Return on assets
9.0%
Revenue growth (QoQ)
-67.7%
Net-income growth
380.2%
Debt / equity
0.2×
Tangible book value
$4.4B
Stock comp / revenue
0.5%
Insider transactions · last 18 months
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| 2026-05-21 | Tanner David Allen | Grant | 135 | — |
| 2026-05-21 | SHANK SUZANNE F. | Grant | 135 | — |
| 2026-05-21 | Hicks Weston M | Grant | 190 | — |
| 2026-05-21 | Gelston Philip A | Grant | 135 | — |
| 2026-05-21 | Dillon Margaret | Grant | 135 | — |
| 2026-05-21 | Chu John | Grant | 135 | — |
| 2026-05-21 | CHOKSI MARY C | Grant | 135 | — |
| 2026-05-21 | Carlson Peter M | Grant | 135 | — |
| 2026-05-21 | CAMPBELL REID TARLTON | Grant | 135 | — |
| 2026-03-19 | SEELIG ROBERT LAWRENCE | Gift | 50 | — |
| 2026-03-04 | Tanner David Allen | Gift | 225 | — |
| 2026-02-25 | Caffrey Liam P | Grant | 1.5K | — |
| 2026-02-25 | Harrison Giles E | Grant | 775 | — |
| 2026-02-25 | Hildreth Michaela | Grant | 600 | — |
| 2026-02-25 | Papamichael Michael A | Grant | 500 | — |
| 2026-02-25 | SEELIG ROBERT LAWRENCE | Grant | 775 | — |
| 2026-01-01 | Hildreth Michaela | Tax withheld | 274 | $2,078.03 |
| 2026-01-01 | Papamichael Michael A | Tax withheld | 131 | $2,078.03 |
| 2026-01-01 | SEELIG ROBERT LAWRENCE | Tax withheld | 398 | $2,078.03 |
| 2026-01-01 | Caffrey Liam P | Tax withheld | 425 | $2,078.03 |
| 2025-12-23 | Hildreth Michaela | Gift | 60 | — |
| 2025-12-19 | CAMPBELL REID TARLTON | Sell | 5.0K | $2,050.00 |
| 2025-12-19 | CAMPBELL REID TARLTON | Sell | 5.0K | — |
| 2025-12-19 | Rountree George Manning | Sell | 5.0K | $2,050.00 |
| 2025-12-16 | Gelston Philip A | Sell | 165 | $2,048.51 |
| 2025-11-25 | CAMPBELL REID TARLTON | Gift | 50 | — |
| 2025-11-10 | Tanner David Allen | Gift | 4 | — |
| 2025-05-22 | SHANK SUZANNE F. | Grant | 150 | — |
| 2025-05-22 | Yi Steven | Grant | 150 | — |
| 2025-05-22 | Tanner David Allen | Grant | 150 | — |
| 2025-05-22 | Hicks Weston M | Grant | 210 | — |
| 2025-05-22 | Gelston Philip A | Grant | 150 | — |
| 2025-05-22 | Dillon Margaret | Grant | 150 | — |
| 2025-05-22 | CHOKSI MARY C | Grant | 150 | — |
| 2025-05-22 | Carlson Peter M | Grant | 150 | — |
| 2025-05-22 | CAMPBELL REID TARLTON | Grant | 150 | — |
| 2025-02-26 | Rountree George Manning | Grant | 1.6K | — |
| 2025-02-26 | Caffrey Liam P | Grant | 1.0K | — |
| 2025-02-26 | Harrison Giles E | Grant | 900 | — |
| 2025-02-26 | SEELIG ROBERT LAWRENCE | Grant | 825 | — |
| 2025-02-26 | Hildreth Michaela | Grant | 625 | — |
| 2025-01-01 | Rountree George Manning | Tax withheld | 1.1K | $1,945.06 |
| 2025-01-01 | Caffrey Liam P | Tax withheld | 420 | $1,945.06 |
| 2025-01-01 | SEELIG ROBERT LAWRENCE | Tax withheld | 496 | $1,945.06 |
| 2025-01-01 | Hildreth Michaela | Tax withheld | 323 | $1,945.06 |
All non-derivative Form 4 activity (SEC), newest first.
Supply chain
Customers (0)
Suppliers (3)
- A.M. Best
- Lloyd's
- Standard & Poor's
Named in the 10-K; linked when we track them.
Notable events (8-K)
| Date | Items | |
|---|---|---|
| 2026-06-05 | Reg FDExhibits | filing ↗ |
| 2026-05-21 | Exec/director changeShareholder voteExhibits | filing ↗ |
| 2026-05-15 | Material agreementDebt obligationExhibits | filing ↗ |
| 2026-05-06 | ResultsExhibits | filing ↗ |
| 2026-04-01 | OtherExhibits | filing ↗ |
| 2026-02-26 | OtherExhibits | filing ↗ |
| 2026-02-06 | ResultsExhibits | filing ↗ |
| 2026-01-07 | Other | filing ↗ |
Recent filings
| Form | Filed | Period | Accession |
|---|---|---|---|
| 8-K | 2026-06-05 | 2026-06-05 | 0001628280-26-041051 ↗ |
| 8-K | 2026-05-21 | 2026-05-21 | 0001628280-26-037284 ↗ |
| 8-K | 2026-05-15 | 2026-05-14 | 0001628280-26-035349 ↗ |
| 10-Q | 2026-05-06 | 2026-03-31 | 0001628280-26-030935 ↗ |
| 8-K | 2026-05-06 | 2026-05-06 | 0001628280-26-030930 ↗ |
| 8-K | 2026-04-01 | 2026-04-01 | 0001628280-26-022818 ↗ |
| 10-K | 2026-02-27 | 2025-12-31 | 0001628280-26-012603 ↗ |
| 8-K | 2026-02-26 | 2026-02-26 | 0001628280-26-012417 ↗ |
| 8-K | 2026-02-06 | 2026-02-06 | 0001628280-26-005947 ↗ |
| 8-K | 2026-01-07 | 2026-01-07 | 0001628280-26-001102 ↗ |
| 8-K | 2025-12-08 | 2025-12-05 | 0001628280-25-055702 ↗ |
| 10-Q | 2025-11-06 | 2025-09-30 | 0001628280-25-049910 ↗ |