Southeastern Asset runs Longleaf, an asset manager overseeing $2.25B in disclosed equity holdings (SEC CIK 0000807985). The latest portfolio (2025Q4) discloses 53 positions across 10 sectors, with the largest positions in CNX, MAT and IAC. On a mark-to-market basis the tracked portfolio has returned 4.2% over the past year. OpenStocks tracks 40 consecutive quarterly snapshots for this manager — every position change, new entry, and exit is logged below.