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 |
|---|---|---|---|---|
| Markel Group | 56.6% | 49 | +9.6% | -4.5% |
| Loews Corporation | 52.3% | 35 | -2.7% | -16.7% |
| Berkshire Hathaway | 27% | 35 | +8.5% | -5.6% |
| Graham Holdings | 21.1% | 35 | +9.2% | -4.9% |
| Cincinnati Financial | 21% | 39 | +11.4% | -2.7% |
| Hingham Institution for Savings | 14.4% | 65 | +12.3% | -1.8% |
| White Mountains Insurance Group | 7% | 38 | +11.7% | -2.4% |
| W.R. Berkley | 3.1% | 35 | +3.2% | -10.9% |
| Nvidia | 0.8% | 35 | +129.5% | +115.5% |
| Alphabet | 0.1% | 42 | +15.6% | +1.5% |
Data updates nightly after U.S. market close. 13-F positions reflect last quarterly filing; prices marked to most recent close.