# Relationship history for MSHA mine 0801080

Current hierarchy: **Parker Robert L → Treasure Coast Aggregates Inc → Treasure Coast Pit**

- 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:** Treasure Coast Mining Inc → Treasure Coast Pit; 1987-09-01 to 1989-05-18; source msha-controller-operator-history
- **controller_controls_mine:** Vest William H → Treasure Coast Pit; 1987-09-01 to 1989-05-18; source msha-controller-operator-history
- **controller_controls_operator:** Vest William H → Treasure Coast Mining Inc; 1987-09-01 to 1989-05-18; source msha-controller-operator-history
- **operator_operates_mine:** Treasure Coast Aggregates Inc → Treasure Coast Pit; 1989-05-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Parker Robert L → Treasure Coast Pit; 1989-05-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Parker Robert L → Treasure Coast Aggregates Inc; 1989-05-19 to current/open; source msha-controller-operator-history