# Relationship history for MSHA mine 1509767

Current hierarchy: **Cannon Herbert S & Company Limited → Stripco Coal Corp → No 1 Surface**

- 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:** Stripco Coal Company Inc → No 1 Surface; 1976-06-01 to 1977-09-17; source msha-controller-operator-history
- **controller_controls_mine:** Burchett Delbert → No 1 Surface; 1976-06-01 to 1977-09-17; source msha-controller-operator-history
- **controller_controls_operator:** Burchett Delbert → Stripco Coal Company Inc; 1976-06-01 to 1977-09-17; source msha-controller-operator-history
- **controller_controls_mine:** Lawson Stanley B → No 1 Surface; 1977-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Stripco Coal Corp → No 1 Surface; 1977-09-18 to 1978-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Lawson Stanley B → Stripco Coal Corp; 1977-09-18 to 1978-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Stripco Coal Corp → No 1 Surface; 1978-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cannon Herbert S & Company Limited → No 1 Surface; 1978-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cannon Herbert S & Company Limited → Stripco Coal Corp; 1978-05-01 to current/open; source msha-controller-operator-history