# Relationship history for MSHA mine 3606523

Current hierarchy: **Percival John P → P & M Mining Company → Pigeon Creek Strip**

- 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

- **controller_controls_mine:** Percival John P Et Al → Pigeon Creek Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Alky Bend Mining Inc → Pigeon Creek Strip; 1977-09-01 to 1978-06-11; source msha-controller-operator-history
- **controller_controls_mine:** De Knecht Abraham → Pigeon Creek Strip; 1977-09-01 to 1979-10-30; source msha-controller-operator-history
- **controller_controls_operator:** De Knecht Abraham → Alky Bend Mining Inc; 1977-09-01 to 1978-06-11; source msha-controller-operator-history
- **operator_operates_mine:** P & M Mining Company → Pigeon Creek Strip; 1978-06-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Percival John P Et Al → P & M Mining Company; 1978-06-12 to current/open; source msha-controller-operator-history