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

SecurityWTM / White Mountains Insurance Group, Ltd.
InstitutionFirst Horizon Advisors, Inc.
Latest Disclosed Ownership48 shares
Latest Disclosed Value $ 86,194
First Horizon Advisors, Inc. reports 2.04% decrease in ownership of WTM / White Mountains Insurance Group, Ltd.

On August 6, 2025 - First Horizon Advisors, Inc. filed a 13F-HR form disclosing ownership of 48 shares of White Mountains Insurance Group, Ltd. (US:WTM) valued at $86,195 USD as of June 30, 2025. The entity filed a previous 13F-HR on April 28, 2025 disclosing 49 shares of White Mountains Insurance Group, Ltd.. This represents a change in shares of -2.04% during the quarter. The current value of the position is $96,746 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)
2025-08-06 2025-06-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 48 -1 -2.04 86 -8.51 0.0022
2025-04-28 2025-03-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 49 13 36.11 94 34.29 0.0027
2025-02-03 2024-12-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 36 -11 -23.40 70 -11.39 0.0020
2024-11-08 2024-09-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 47 2 4.44 80 -2.47 0.0022
2024-07-19 2024-06-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 45 0 0.00 82 1.25 0.0025
2024-04-26 2024-03-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 45 8 21.62 81 45.45 0.0025
2024-02-06 2023-12-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 37 4 12.12 56 12.24 0.0018
2023-10-27 2023-09-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 33 -5 -13.16 49 -5.77 0.0018
2023-08-03 2023-06-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 38 13 52.00 53 52.94 0.0018
2023-05-15 2023-03-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 25 0 0.00 34 -2.86 0.0012
2023-02-10 2022-12-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 25 0 0.00 35 9.38 0.0013
2022-11-09 2022-09-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 25 0 0.00 32 6.67 0.0013
2022-08-02 2022-06-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 25 25 30 0.0011
2022-05-10 2022-03-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 0 -25 -100.00 0 -100.00
2022-02-09 2021-12-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 25 0 0.00 25 -3.85 0.0008
2021-11-15 2021-09-30 13F/A-1 WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 25 1 4.17 26 0.00 0.0008
2021-11-09 2021-09-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 997 973 59 0.0009
2021-08-09 2021-06-30 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 24 -1 -4.00 26 -3.70 0.0014
2021-05-11 2021-03-31 13F WHITE MTNS INS GROUP LTD COM COMMON STOCK G9618E107 25 5 25.00 27 35.00 0.0016
2021-02-11 2020-12-31 13F WHITE MOUNTAINS INSURANCE GROUP COMMON STOCK G9618E107 20 3 17.65 20 53.85 0.0013
2020-11-12 2020-09-30 13F WHITE MOUNTAINS INSURANCE GROUP COMMON STOCK G9618E107 17 0 0.00 13 -13.33 0.0010
2020-07-31 2020-06-30 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 17 -4 -19.05 15 -21.05 0.0012
2020-05-05 2020-03-31 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 Common Stock G9618E107 21 -15 -41.67 19 -52.50 0.0018
2020-01-07 2019-12-31 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 36 0 0.00 40 5.26 0.0029
2019-10-23 2019-09-30 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 36 3 9.09 38 15.15 0.0030
2019-08-05 2019-06-30 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 33 0 0.00 33 10.00 0.0025
2019-04-26 2019-03-31 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 33 0 0.00 30 7.14 0.0024
2019-02-11 2018-12-31 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 33 0 0.00 28 -6.67 0.0025
2018-11-08 2018-09-30 13F/A-2 WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 33 0 0.00 30 3.45 0.0023
2018-11-05 2018-09-30 13F/A-1 WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 33 0 308 0.0172
2018-11-05 2018-09-30 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 33 0 308 0.0284
2018-08-06 2018-06-30 13F WHITE MOUNTAINS INSURANCE GROUP COM USD1 COMMON STOCK G9618E107 33 33 -32.65 29 3.57 0.0024
2014-02-07 2013-12-31 13F WHITE MOUNTAINS Common Stock G9618E107 0 -64 -100.00 0 -100.00
2013-11-15 2013-09-30 13F WHITE MOUNTAINS INSURANCE GP COMMON STOCK G9618E107 64 15 30.61 36 28.57 0.0058
2014-02-25 2013-06-30 13F WHITE MOUNTAINS Common Stock G9618E107 49 49 28 0.0143
2014-02-25 2012-09-30 13F WHITE MOUNTAINS COMMON STOCK G9618E107 0 -49 -100.00 0 -100.00
2014-02-25 2012-06-30 13F WHITE MOUNTAINS COMMON STOCK G9618E107 49 -36 -42.35 28 -39.13 0.0221
2014-02-25 2012-03-31 13F WHITE MOUNTAINS COMMON STOCK G9618E107 85 85 46 0.0381
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.