HoldcoTracker marks the reported 13-F equity portfolios of operating and holding companies to last close. Institutional investors with over $100 million in U.S. equities file 13-Fs disclosing those holdings within 45 days of each quarter-end; the lead column below sizes each filer's equity book against the parent company's market cap.
| Company | 13-F as % of Mkt Cap | Days Since Filing | Since Filing | vs S&P since filing |
|---|---|---|---|---|
| Loews Corporation | 57.2% | 77 | +15.7% | +2.5% |
| Markel Group | 55.8% | 91 | +10.3% | -2.9% |
| Berkshire Hathaway | 27.8% | 77 | +16% | +2.9% |
| Cincinnati Financial | 20.3% | 81 | +10.6% | -2.5% |
| Graham Holdings | 19.7% | 77 | +8.8% | -4.3% |
| Hingham Institution for Savings | 15.5% | 10 | +1.5% | +2.1% |
| White Mountains Insurance Group | 7.8% | 80 | +30.8% | +17.6% |
| W.R. Berkley | 2.9% | 77 | +5% | -8.1% |
| Nvidia | 0.6% | 77 | +55.4% | +42.2% |
| Alphabet | 0.1% | 84 | +0.6% | -12.5% |
Data updates nightly after U.S. market close. 13-F positions reflect last quarterly filing; prices marked to most recent close.