# Relationship history for MSHA mine 3200799

Current hierarchy: **Dean O  Oakland → Oakland & Fisher Construction Incorporated → Portable #2**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Oakland & Fisher Construction Incorporated → Portable #2; 2002-05-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dean O  Oakland → Portable #2; 2002-05-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dean O  Oakland → Oakland & Fisher Construction Incorporated; 2002-05-20 to current/open; source msha-controller-operator-history