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

SecurityWTM / White Mountains Insurance Group, Ltd.
InstitutionPhocas Financial Corp.
Latest Disclosed Ownership4,292 shares
Latest Disclosed Value $ 9,429,352
Phocas Financial Corp. reports 21.84% decrease in ownership of WTM / White Mountains Insurance Group, Ltd.

On May 1, 2026 - Phocas Financial Corp. filed a 13F-HR form disclosing ownership of 4,292 shares of White Mountains Insurance Group, Ltd. (US:WTM) valued at $9,429,352 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on January 26, 2026 disclosing 5,491 shares of White Mountains Insurance Group, Ltd.. This represents a change in shares of -21.84% during the quarter. The current value of the position is $8,650,698 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)
2026-05-01 2026-03-31 13F WHITE MTNS INS GROUP COM G9618E107 4,292 -1,199 -21.84 9,429 -17.36 1.4806
2026-01-26 2025-12-31 13F/A-1 WHITE MTNS INS GROUP COM G9618E107 5,491 -14 -0.25 11,410 24.01 1.4839
2026-01-21 2025-12-31 13F WHITE MTNS INS GROUP COM G9618E107 5,491 -14 11,410 1.5171
2025-11-12 2025-09-30 13F WHITE MTNS INS GROUP COM G9618E107 5,505 113 2.10 9,202 -4.97 1.1929
2025-08-06 2025-06-30 13F WHITE MTNS INS GROUP COM G9618E107 5,392 1 0.02 9,683 -6.74 1.3925
2025-05-09 2025-03-31 13F WHITE MTNS INS GROUP COM G9618E107 5,391 -311 -5.45 10,382 -6.39 1.5917
2025-03-05 2024-12-31 13F/A-1 WHITE MTNS INS GROUP COM G9618E107 5,702 5,702 11,091 1.4812
2025-02-05 2024-12-31 13F WHITE MTNS INS GROUP COM G9618E107 864 864 1,681 1.2507
2024-05-01 2024-03-31 13F/A-1 WHITE MTNS INS GROUP COM G9618E107 0 -5,113 -100.00 0 -100.00
2024-04-18 2024-03-31 13F WHITE MTNS INS GROUP COM G9618E107 0 0
2024-01-30 2023-12-31 13F WHITE MTNS INS GROUP COM G9618E107 5,113 97 1.93 7,695 2.57 1.0169
2023-10-10 2023-09-30 13F WHITE MTNS INS GROUP COM G9618E107 5,016 -6 -0.12 7,502 7.56 1.0908
2023-07-13 2023-06-30 13F WHITE MTNS INS GROUP COM G9618E107 5,022 -35 -0.69 6,975 0.13 0.9544
2023-04-13 2023-03-31 13F WHITE MTNS INS GROUP COM G9618E107 5,057 51 1.02 6,966 -1.61 0.9986
2023-01-11 2022-12-31 13F WHITE MTNS INS GROUP COM G9618E107 5,006 -1,631 -24.57 7,080 -18.13 1.0198
2022-10-14 2022-09-30 13F WHITE MTNS INS GROUP COM G9618E107 6,637 214 3.33 8,648 8.05 1.3396
2022-08-15 2022-06-30 13F WHITE MTNS INS GROUP COM G9618E107 6,423 -66 -1.02 8,004 8.56 1.1991
2022-05-25 2022-03-31 13F WHITE MTNS INS GROUP COM G9618E107 6,489 -104 -1.58 7,373 10.29 0.9175
2022-02-15 2021-12-31 13F WHITE MTNS INS GROUP COM G9618E107 6,593 6,593 6,685 0.8509
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.