# Relationship history for MSHA mine 0102935

Current hierarchy: **Calvert John A → Pine Mountain Energy Inc → Wheat-Ardell 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:** Pine Mountain Energy Inc → Wheat-Ardell Mine; 1991-12-01 to 1992-05-06; source msha-controller-operator-history
- **controller_controls_mine:** Lollar Perry D → Wheat-Ardell Mine; 1991-12-01 to 1992-05-06; source msha-controller-operator-history
- **controller_controls_operator:** Lollar Perry D → Pine Mountain Energy Inc; 1991-12-01 to 1992-05-06; source msha-controller-operator-history
- **operator_operates_mine:** Pine Mountain Energy Inc → Wheat-Ardell Mine; 1992-05-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Calvert John A → Wheat-Ardell Mine; 1992-05-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Calvert John A → Pine Mountain Energy Inc; 1992-05-07 to current/open; source msha-controller-operator-history