# Relationship history for MSHA mine 1201984

Current hierarchy: **Harrison Wade C Ii → Harrison Steel Castings Company Inc → Harrison Steel Castings**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Harrison Steel Castings Company Inc → Harrison Steel Castings; 1986-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Harrison Wade C Ii → Harrison Steel Castings; 1986-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harrison Wade C Ii → Harrison Steel Castings Company Inc; 1986-07-01 to current/open; source msha-controller-operator-history