# Relationship history for MSHA mine 1201716

Current hierarchy: **Damon G  Fortune → B F C Coal Company Inc → Knight Chapel 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:** B F C Coal Company Inc → Knight Chapel Mine; 1979-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Damon G  Fortune → Knight Chapel Mine; 1979-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Damon G  Fortune → B F C Coal Company Inc; 1979-08-01 to current/open; source msha-controller-operator-history