# WHITE MTNS INS GROUP LTD COM

WHITE MTNS INS GROUP LTD COM is a security (CUSIP G9618E107) tracked across SEC portfolio filings. 370 institutional managers reported $4.5B on Form 13F as of 2026-06-30; 15 registered fund positions totaling $111.8M via N-PORT as of 2026-06-30.

## Summary

- Issuer: WHITE MTNS INS GROUP LTD
- Class: COM
- CUSIP: G9618E107
- Asset category: EC
- 13F holders: 370
- 13F value: $4.5B
- 13F period: 2026-06-30
- N-PORT fund positions: 15
- N-PORT value: $111.8M
- N-PORT report: 2026-06-30

## Top institutional holders (Form 13F)

_Showing 15 of 370 managers by value._

| Manager | Location | Value | Shares |
| --- | --- | --- | --- |
| [VANGUARD GROUP INC](https://search.stillhousedata.com/firm/105958) | Valley Forge, PA | $489.8M | 235,698 |
| DIMENSIONAL FUND ADVISORS LP | AUSTIN, TX | $344.1M | 156,618 |
| NEUBERGER BERMAN GROUP LLC | NEW YORK, NY | $274.0M | 124,715 |
| BlackRock, Inc. | New York, NY | $249.0M | 113,328 |
| [River Road Asset Management, LLC](https://search.stillhousedata.com/firm/134918) | LOUISVILLE, KY | $240.3M | 115,880 |
| FULLER & THALER ASSET MANAGEMENT, INC. | San Mateo, CA | $229.7M | 104,561 |
| [FIDUCIARY MANAGEMENT INC /WI/](https://search.stillhousedata.com/firm/109149) | MILWAUKEE, WI | $186.9M | 85,066 |
| [COOKE & BIELER LP](https://search.stillhousedata.com/firm/113859) | PHILADELPHIA, PA | $176.5M | 85,120 |
| Wallace Capital Management Inc. | DALLAS, TX | $173.1M | 78,795 |
| MORGAN STANLEY | NEW YORK, NY | $130.3M | 59,295 |
| [LONDON CO OF VIRGINIA](https://search.stillhousedata.com/firm/106654) | RICHMOND, VA | $125.5M | 57,131 |
| Boston Partners | BOSTON, MA | $115.3M | 55,569 |
| STATE STREET CORP | BOSTON, MA | $108.0M | 49,158 |
| [GEODE CAPITAL MANAGEMENT, LLC](https://search.stillhousedata.com/firm/115504) | BOSTON, MA | $92.6M | 42,119 |
| [REINHART PARTNERS, LLC.](https://search.stillhousedata.com/firm/106432) | MEQUON, WI | $92.3M | 44,480 |

## Top fund holders (N-PORT)

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [VANGUARD EXTENDED MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002841) | VANGUARD INDEX FUNDS | $60.0M | 7.36% |
| [Longleaf Partners Small Cap Fund](https://search.stillhousedata.com/fund/S000009312) | Longleaf Partners Funds Trust | $33.5M | 481.44% |
| [Bridge Builder Tax Managed Small/Mid Cap Fund](https://search.stillhousedata.com/fund/S000076295) | Bridge Builder Trust | $9.0M | 29.70% |
| [VANGUARD BALANCED INDEX FUND](https://search.stillhousedata.com/fund/S000002560) | VANGUARD VALLEY FORGE FUNDS | $3.0M | 0.51% |
| [VANGUARD INSTITUTIONAL TOTAL STOCK MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002855) | VANGUARD INSTITUTIONAL INDEX FUNDS | $2.6M | 0.85% |
| Nuveen Core Equity Alpha Fund | Nuveen Core Equity Alpha Fund | $1.4M | 51.64% |
| [VANGUARD TAX-MANAGED BALANCED FUND](https://search.stillhousedata.com/fund/S000004383) | VANGUARD TAX-MANAGED FUNDS | $1.1M | 0.97% |
| [Vericimetry U.S. Small Cap Value Fund](https://search.stillhousedata.com/fund/S000033942) | VERICIMETRY FUNDS | $648K | 38.56% |
| EAGLE CAPITAL GROWTH FUND, INC. | EAGLE CAPITAL GROWTH FUND, INC. | $622K | 128.82% |
| [First Investors Hedged U.S. Equity Opportunities Fund](https://search.stillhousedata.com/fund/S000054700) | FIRST INVESTORS EQUITY FUNDS | $229K | 18.49% |
| [TIAA Separate Account VA-1 - Stock Index Account](https://search.stillhousedata.com/fund/S000005098) | TIAA Separate Account VA-1 | $119K | 0.92% |
| [Dynamic Allocation Fund](https://search.stillhousedata.com/fund/S000003615) | Meeder Funds | $70K | 1.19% |
| [Humankind U.S. Stock ETF](https://search.stillhousedata.com/fund/S000069946) | Humankind Benefit Corp | $7K | 0.41% |
| RENN Fund, Inc. | RENN FUND, INC. | $4K | 1.88% |
| [VANGUARD MARKET NEUTRAL FUND](https://search.stillhousedata.com/fund/S000019457) | VANGUARD MONTGOMERY FUNDS | $-455K | -10.54% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/G9618E107.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.