White Mountains Insurance Group, Ltd.
US ˙ NYSE ˙ BMG9618E1075

SecurityWTM / White Mountains Insurance Group, Ltd.
InstitutionExodusPoint Capital Management, LP
Latest Disclosed Ownership611 shares
Latest Disclosed Value $ 1,342,343
ExodusPoint Capital Management, LP reports 52.37% increase in ownership of WTM / White Mountains Insurance Group, Ltd.

On May 14, 2026 - ExodusPoint Capital Management, LP filed a 13F-HR form disclosing ownership of 611 shares of White Mountains Insurance Group, Ltd. (US:WTM) valued at $1,342,343 USD as of March 31, 2026. The entity filed a previous 13F-HR on November 14, 2025 disclosing 401 shares of White Mountains Insurance Group, Ltd.. This represents a change in shares of 52.37% during the quarter. The current value of the position is $1,261,801 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-14 2026-03-31 13F WHITE MTNS INS GROUP COM G9618E107 611 210 52.37 1,342 100.30 0.0108
2025-11-14 2025-09-30 13F WHITE MTNS INS GROUP COM G9618E107 401 45 12.64 670 0.0068
2025-08-13 2025-06-30 13F WHITE MTNS INS GROUP COM G9618E107 356 -326 -47.80 1 -100.00 0.0056
2025-05-14 2025-03-31 13F WHITE MTNS INS GROUP COM G9618E107 682 280 69.65 1 0.0130
2025-02-12 2024-12-31 13F WHITE MTNS INS GROUP COM G9618E107 402 -407 -50.31 1 -100.00 0.0054
2024-11-12 2024-09-30 13F WHITE MTNS INS GROUP COM G9618E107 809 674 499.26 1 0.0084
2024-08-13 2024-06-30 13F WHITE MTNS INS GROUP COM G9618E107 135 135 0 0.0017
2024-02-13 2023-12-31 13F WHITE MTNS INS GROUP COM G9618E107 0 -1,067 -100.00 0 -100.00
2023-11-13 2023-09-30 13F WHITE MTNS INS GROUP COM G9618E107 1,067 1,067 2 0.0152
2022-08-20 2022-06-30 13F WHITE MTNS INS GROUP COM G9618E107 0 -4,699 -100.00 0 -100.00
2022-05-13 2022-03-31 13F WHITE MTNS INS GROUP COM G9618E107 4,699 4,296 1,066.00 5,339 1,205.38 0.0675
2022-02-11 2021-12-31 13F WHITE MTNS INS GROUP COM G9618E107 403 -1,391 -77.54 409 -78.69 0.0042
2021-11-15 2021-09-30 13F WHITE MTNS INS GROUP COM G9618E107 1,794 276 18.18 1,919 10.10 0.0259
2021-08-16 2021-06-30 13F WHITE MTNS INS GROUP COM G9618E107 1,518 -281 -15.62 1,743 -13.11 0.0193
2021-05-17 2021-03-31 13F WHITE MTNS INS GROUP COM G9618E107 1,799 -216 -10.72 2,006 -0.50 0.0293
2021-02-16 2020-12-31 13F WHITE MTNS INS GROUP COM G9618E107 2,015 2,015 2,016 0.0196
2020-08-14 2020-06-30 13F WHITE MTNS INS GROUP WHITE MTNS INS GROUP LTD G9618E107 0 -257 -100.00 0 -100.00
2020-05-15 2020-03-31 13F WHITE MTNS INS GROUP WHITE MTNS INS GROUP LTD G9618E107 257 257 234 0.0128
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.