WTMWhite Mountains Insurance Group, Ltd.Financial Services · Insurance - Diversifiedas of 2026-09-16
Horizon

Issued 2026-09-16 at $2062.37 · now $2062.37 (2026-09-16, +0.0% since)

Based on its own history, a month from the 2026-09-16 close, WTM has typically landed between $1905.51 and $2270.72 — a range of −7.6% to +10.1% from the issuance price $2062.37.

Range of outcomes in historically similar periods — not a price prediction. Ranges are scored publicly on /methodology.
  • Actual close
  • Typical path (median)
  • Middle 50% of outcomes
  • 90% range

5,003 overlapping 1 month windows · 2006-09-26 – 2026-08-17 · basis climatology · forecast (batch). Probability up 53.9% (90% CI 51.7–56.1%, ≈1,408 obs).

The cone is anchored at the 2026-09-16 issuance close ($2062.37) — the price the forecast resolves against on 2026-10-15, not the latest close. The drawn path shape is illustrative (bands widen with √t); every labeled number is real — the anchor, the scored batch p90/IQR endpoints, and the typical move.

Where WTM has typically landed a month from the 2026-09-16 close of $2,062 — the range is history, not a prediction.

$1,906worst · -7.6%$2,271best · +10.1%
  • now $2,062 (+0.0%)
  • typicalThe typical outcome — half of similar past periods did better and half did worse (not an average, so a few wild periods don't skew it). $2,080 (+0.9%)
  • middle 50%The central range of outcomes — half of similar past periods landed inside it, a quarter finished above, a quarter below. $2,007–$2,153
  • 90% rangeA nine-in-ten range — in about nine of every ten similar past periods the outcome stayed within these bounds. $1,906–$2,271
Actual 1-month windows behind the coneiEvery overlapping 1-month window in this security's own price history was ranked by realized return; shown are the 3 worst and 3 best of 5,003 windows spanning 2006-09-26 to 2026-09-16. Not cherry-picked — these are the extremes of the full sample. Max drop / max rise are the deepest and highest points reached within each window. See /methodology.
StartReturnMax dropMax rise
3 worst
2020-02-18−39.2%−39.2%+0.3%
2020-02-20−38.5%−39.1%+0.0%
2020-02-21−38.0%−39.0%+0.0%
3 best
2009-07-15+31.7%+0.0%+31.7%
2009-07-22+31.0%+0.0%+31.0%
2009-07-30+30.3%+0.0%+31.3%

5,003 overlapping windows · 2006-09-26 – 2026-09-16 · not cherry-picked

Seasonality · by month iHow this security has tended to do in each calendar month historically — a frequency, never a prediction.

iFor each calendar month, the share of years this security closed higher than the month before, and the average month-over-month return, over ~20 years of its own price history. Cells are shaded by average return. This is historical frequency, not a prediction — no month is a signal.
Jan
55%
+0.5%
n=20
Feb
70%
+2.5%
n=20
Mar
50%
−0.8%
n=20
Apr
55%
+0.9%
n=20
May
60%
+1.8%
n=20
Jun
75%
+0.4%
n=20
Jul
45%
+1.1%
n=20
Aug
70%
+1.9%
n=20
Sep
35%
−2.0%
n=20
Oct
60%
+2.2%
n=20
Nov
75%
+1.2%
n=20
Dec
50%
−0.2%
n=20

Up-frequency and average month-over-month return · historical frequency, not a prediction

Reported insider & political trades

Every Form 4 the people closest to this company have filed with the SEC — plotted against the share price, aggregated by month, and shown with the gap between when each trade happened and when it was disclosed. A public record, not advice.

Share price & reported tradesMonthly open-market valueReporting lag — trade date to filing date2026-092026-082026-072026-062026-052026-042026-032026-022026-012025-122025-112025-102025-092025-08$2K$2K2025-12-19: 2 insider sales, $10.3M — Rountree George Manning, CAMPBELL REID TARLTON2025-12-16: 1 insider sale, $338K — Gelston Philip A2025-12: 3 open-market sales, $10.6M↑ buys↓ salesdirector Rountree George Manning — Sale on 2025-12-19, filed 3 days after the tradedirector CAMPBELL REID TARLTON — Sale on 2025-12-19, filed 3 days after the tradedirector Gelston Philip A — Sale on 2025-12-16, filed same day
DatePersonRoleActionShares @ priceValueOwnership Δvs S&P 1mvs S&P 6mOwned afterFiling
2025-12-19Rountree George ManningdirectorSale5,000 @ $2050.00$10.3M−26.6% of holding+0.2%−9.2%13,809Form 4 · filed 3 days after the trade
2025-12-19CAMPBELL REID TARLTONdirectorSale5,000 @ $0.00$0−32.4% of holding+0.2%−9.2%10,440Form 4 · filed 3 days after the trade
2025-12-16Gelston Philip AdirectorSale165 @ $2048.51$338K−9.5% of holding−1.6%−12.4%1,568Form 4 · filed same day

The vs-S&P columns are a labeled look-back on what the stock did after each filing, measured against the index over the same window. Descriptive history, not a claim about the person or a reason to trade.

43 award / exercise / gift records — not counted as purchases

Awards, option exercises, gifts and tax-withholding disposals are shown separately and never counted as open-market purchases or sales — they carry no conviction information.

DatePersonRoleActionSharesOwned afterFiling
2026-08-31Tanner David AllendirectorGift22,012Form 4
2026-08-26Klar StephendirectorAward / grant113113Form 4
2026-05-21Chu JohndirectorAward / grant135335Form 4
2026-05-21CAMPBELL REID TARLTONdirectorAward / grant13510,575Form 4
2026-05-21CHOKSI MARY CdirectorAward / grant1351,993Form 4
2026-05-21Dillon MargaretdirectorAward / grant1351,080Form 4
2026-05-21Gelston Philip AdirectorAward / grant1351,703Form 4
2026-05-21SHANK SUZANNE F.directorAward / grant1351,006Form 4
2026-05-21Tanner David AllendirectorAward / grant1352,014Form 4
2026-05-21Hicks Weston MdirectorAward / grant1902,936Form 4
2026-05-21Carlson Peter MdirectorAward / grant135852Form 4
2026-03-19SEELIG ROBERT LAWRENCEofficerGift5017,857Form 4
2026-03-04Tanner David AllendirectorGift2251,879Form 4
2026-02-25SEELIG ROBERT LAWRENCEofficerAward / grant7752,500Form 4
2026-02-25Hildreth MichaelaofficerAward / grant6001,825Form 4
2026-02-25Harrison Giles EofficerAward / grant7752,675Form 4
2026-02-25Papamichael Michael AofficerAward / grant5001,200Form 4
2026-02-25Caffrey Liam PdirectorAward / grant1,5003,650Form 4
2026-01-01Caffrey Liam PdirectorWithheld for tax4251,655Form 4
2026-01-01SEELIG ROBERT LAWRENCEofficerWithheld for tax39817,907Form 4
2026-01-01Hildreth MichaelaofficerWithheld for tax2742,491Form 4
2026-01-01Papamichael Michael AofficerWithheld for tax131772Form 4
2025-12-23Hildreth MichaelaofficerGift602,165Form 4
2025-11-25CAMPBELL REID TARLTONdirectorGift5015,440Form 4
2025-11-10Tanner David AllendirectorGift42,104Form 4
2025-05-22CAMPBELL REID TARLTONdirectorAward / grant15015,490Form 4
2025-05-22CHOKSI MARY CdirectorAward / grant1501,858Form 4
2025-05-22Dillon MargaretdirectorAward / grant150945Form 4
2025-05-22Hicks Weston MdirectorAward / grant2102,746Form 4
2025-05-22SHANK SUZANNE F.directorAward / grant150871Form 4
2025-05-22Yi StevendirectorAward / grant150525Form 4
2025-05-22Gelston Philip AdirectorAward / grant1501,733Form 4
2025-05-22Carlson Peter MdirectorAward / grant150717Form 4
2025-05-22Tanner David AllendirectorAward / grant1502,108Form 4
2025-02-26Caffrey Liam PdirectorAward / grant1,0253,400Form 4
2025-02-26Harrison Giles EofficerAward / grant9001,900Form 4
2025-02-26Hildreth MichaelaofficerAward / grant6251,825Form 4
2025-02-26SEELIG ROBERT LAWRENCEofficerAward / grant8252,725Form 4
2025-02-26Rountree George ManningdirectorAward / grant1,6255,425Form 4
2025-01-01Rountree George ManningdirectorWithheld for tax1,06718,809Form 4

Source: SEC Form 4 filings. Each row links to its original filing.

Across 2012–2021, stocks where a CEO, C-suite officer, or director had recently made an open-market common-stock purchase ran about +28 bp per month above the universe average (n=34,268 stock-weeks). A historical tendency, not a prediction.

Congressional disclosures

No congressional trades disclosed for this company.

Research tool, not investment advice — historical frequencies, not recommendations. A product of Marovel Technologies LLC. Full terms.