WHITE MOUNTAINS INSURANCE GROUP LTD WTM
CIK 0000776867 · CUSIP G9618E107
Quarter-end disclosures, not live holdings.
Top 20 institutions
Weight means this stock's share of the manager's own portfolio.
| # | Manager | Value | Manager weight | Change vs prior | Source | |
|---|---|---|---|---|---|---|
| 01 | VANGUARD GROUP INC CIK 102909 · View history | $425.38M 250,783 shares | 0.01% | -252(-0.1%)Reduced | SEC filing ↗ Nov 13, 2024 | ▾ |
| 02 | MORGAN STANLEY CIK 895421 · Amended · View history | $303.69M 179,037 shares | 0.02% | -5.90K(-3.2%)Reduced | SEC filing ↗ May 14, 2025 | ▾ |
| 03 | DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history | $268.91M 158,534 shares | 0.07% | -1.03K(-0.6%)Reduced | SEC filing ↗ Nov 7, 2024 | ▾ |
| 04 | FULLER & THALER ASSET MANAGEMENT, INC. CIK 1082327 · View history | $207.41M 122,277 shares | 0.81% | -7.01K(-5.4%)Reduced | SEC filing ↗ Nov 13, 2024 | ▾ |
| 05 | River Road Asset Management, LLC CIK 1341401 · View history | $200.50M 118,206 shares | 2.62% | +1.89K(+1.6%)Added | SEC filing ↗ Oct 30, 2024 | ▾ |
| 06 | BlackRock, Inc. CIK 2012383 · View history | $195.27M 115,123 shares | 0.00% | — | SEC filing ↗ Nov 13, 2024 | ▾ |
| 07 | Boston Partners CIK 1386060 · View history | $144.98M 85,097 shares | 0.17% | -2.57K(-2.9%)Reduced | SEC filing ↗ Nov 12, 2024 | ▾ |
| 08 | Wallace Capital Management Inc. CIK 1459754 · View history | $139.71M 82,366 shares | 18.92% | +1.06K(+1.3%)Added | SEC filing ↗ Nov 14, 2024 | ▾ |
| 09 | LONDON CO OF VIRGINIA CIK 1259887 · View history | $118.48M 69,853 shares | 0.62% | +3.40K(+5.1%)Added | SEC filing ↗ Nov 14, 2024 | ▾ |
| 10 | WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history | $102.92M 60,675 shares | 0.02% | -9.11K(-13.1%)Reduced | SEC filing ↗ Nov 14, 2024 | ▾ |
| 11 | T. Rowe Price Investment Management, Inc. CIK 1897612 · View history | $97.84M 57,683 shares | 0.06% | -73(-0.1%)Reduced | SEC filing ↗ Nov 14, 2024 | ▾ |
| 12 | STATE STREET CORP CIK 93751 · View history | $93.08M 54,877 shares | 0.00% | +2.71K(+5.2%)Added | SEC filing ↗ Nov 14, 2024 | ▾ |
| 13 | FIDUCIARY MANAGEMENT INC /WI/ CIK 764532 · View history | $83.66M 49,320 shares | 0.73% | -36(-0.1%)Reduced | SEC filing ↗ Nov 14, 2024 | ▾ |
| 14 | BANK OF AMERICA CORP /DE/ CIK 70858 · Amended · View history | $72.02M 42,459 shares | 0.01% | +1.27K(+3.1%)Added | SEC filing ↗ Nov 14, 2024 | ▾ |
| 15 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $67.60M 39,844 shares | 0.01% | +273(+0.7%)Added | SEC filing ↗ Nov 12, 2024 | ▾ |
| 16 | REINHART PARTNERS, LLC. CIK 1080298 · View history | $66.78M 39,369 shares | 2.54% | +1.49K(+3.9%)Added | SEC filing ↗ Oct 9, 2024 | ▾ |
| 17 | Select Equity Group, L.P. CIK 1592643 · View history | $58.80M 34,663 shares | 0.21% | -24.70K(-41.6%)Reduced | SEC filing ↗ Nov 14, 2024 | ▾ |
| 18 | NEUBERGER BERMAN GROUP LLC CIK 1465109 · View history | $56.16M 33,110 shares | 0.04% | +15.95K(+92.9%)Added | SEC filing ↗ Nov 14, 2024 | ▾ |
| 19 | LORD, ABBETT & CO. LLC CIK 728100 · Amended · View history | $55.99M 33,012 shares | 0.18% | +2.43K(+7.9%)Added | SEC filing ↗ Dec 13, 2024 | ▾ |
| 20 | NORGES BANK CIK 1374170 · Amended · View history | $52.03M 30,673 shares | 0.01% | +567(+1.9%)Added | SEC filing ↗ Nov 13, 2024 | ▾ |
Showing 20 / 304 institutions. The complete set is available through the API.
Coverage & totals by quarter
Reporting institutions by quarter
Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.
Explore all 304 reporting institutions.
This page includes 20 of 304 reporting institutions. Sign in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.
- Download CSV
- Earlier quarters
- Advanced screening & filtering
- API & AI access
+ New accounts get free API credits to explore data beyond ownership filings.
For AI agents & developers
The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. This page lists 20 of 304 reporting institutions; totals use the complete disclosed data.
Without an account: the last 3 years, with the row caps stated on the page. A free account opens all history on file on these pages and the CSV of what a page shows. Rows beyond the caps and bulk retrieval go through the authenticated API / MCP.
MCP https://api.akkrudata.ai/mcp
get_institutional_security_holders
{"cusip":"G9618E107","quarter":"2024Q3","type":"positions","page_size":100}Connect to MCP with OAuth and follow the returned pagination. Credits and usage limits depend on the account.
- MCP endpoint
- https://api.akkrudata.ai/mcp
- API / MCP documentation
- /documents
- llms.txt
- /llms.txt
Sources, coverage & how to read this data
Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.