# Relationship history for MSHA mine 1517126

Current hierarchy: **Smith Christopher S → Riggs Energy Inc → #1**

- 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:** Future Mining Company → #1; 1991-09-01 to 1993-08-30; source msha-controller-operator-history
- **controller_controls_mine:** Tyree Charles E Et Al → #1; 1991-09-01 to 1993-08-30; source msha-controller-operator-history
- **controller_controls_operator:** Tyree Charles E Et Al → Future Mining Company; 1991-09-01 to 1993-08-30; source msha-controller-operator-history
- **operator_operates_mine:** Natural Mining Inc → #1; 1993-08-31 to 1996-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Jones Darrell Ray → #1; 1993-08-31 to 1996-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Jones Darrell Ray → Natural Mining Inc; 1993-08-31 to 1996-07-09; source msha-controller-operator-history
- **operator_operates_mine:** Hut Coal Company Inc → #1; 1996-07-10 to 1997-04-23; source msha-controller-operator-history
- **controller_controls_mine:** Reeves Henderson D → #1; 1996-07-10 to 1997-04-23; source msha-controller-operator-history
- **controller_controls_operator:** Reeves Henderson D → Hut Coal Company Inc; 1996-07-10 to 1997-04-23; source msha-controller-operator-history
- **operator_operates_mine:** Riggs Energy Inc → #1; 1997-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Smith Christopher S → #1; 1997-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Smith Christopher S → Riggs Energy Inc; 1997-04-24 to current/open; source msha-controller-operator-history