# Relationship history for MSHA mine 3604015

Current hierarchy: **Old Devon Inc; S C Coal Corporation → Reitz Coal Company → #4 Cleaning Plant**

- 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:** Reitz Coal Company → #4 Cleaning Plant; 1950-01-01 to 1983-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Berwind Corporation → #4 Cleaning Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Berwind Corporation → Reitz Coal Company; 1950-01-01 to 1983-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Reitz Coal Company → #4 Cleaning Plant; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** S C Coal Corporation et al → #4 Cleaning Plant; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** S C Coal Corporation et al → Reitz Coal Company; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Old Devon Inc et al → Reitz Coal Company; 1983-07-01 to current/open; source msha-controller-operator-history