# Relationship history for MSHA mine 0504246

Current hierarchy: **Randall & Blake Inc → Landmark Reclamation Inc → Rimrock Coal Mine**

- 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:** Rimrock Coal Company → Rimrock Coal Mine; 1987-07-01 to 1992-12-13; source msha-controller-operator-history
- **controller_controls_mine:** Davis W T → Rimrock Coal Mine; 1987-07-01 to 1992-12-13; source msha-controller-operator-history
- **controller_controls_operator:** Davis W T → Rimrock Coal Company; 1987-07-01 to 1992-12-13; source msha-controller-operator-history
- **operator_operates_mine:** Landmark Reclamation Inc → Rimrock Coal Mine; 1992-12-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Randall & Blake Inc → Rimrock Coal Mine; 1992-12-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Randall & Blake Inc → Landmark Reclamation Inc; 1992-12-14 to current/open; source msha-controller-operator-history