Southeastern Asset Management (Longleaf)
SuperinvestorSoutheastern Asset Management Inc
- SEC CIK
- 0000807985
- Manager
- Mason Hawkins
- Style
- Value
- Latest filing
- Aug 14, 2026
AVTR holding history
Avantor, Inc. in every 13F filed by Southeastern Asset Management (Longleaf), including the quarters it was sold out or no filing was made. Changes compare share counts with the previous calendar quarter.
AVTR overviewAll 13F holders of AVTRFull Q2 2026 holdings
- Shares (Q2 2026)
- 4,725,478
- Value
- $46.8M
- % of portfolio
- 2.4%
- Quarters held
- 4
- Since Q3 2025
| Quarter | Shares | Value | % of portfolio | Share change | Action | All holders |
|---|---|---|---|---|---|---|
| Q2 2026 | 4,725,478 | $46.8M | 2.4% | +1,205,266+34.2% | Added | Holders |
| Q1 2026 | 3,520,212 | $27.6M | 1.4% | −28,306−0.8% | Reduced | Holders |
| Q4 2025 | 3,548,518 | $40.7M | 1.8% | −1,600,902−31.1% | Reduced | Holders |
| Q3 2025 | 5,149,420 | $64.3M | 3.3% | +5,149,420 | New | Holders |