# Relationship history for MSHA mine 4403518

Current hierarchy: **United  Company → Wellmore Coal Corp No 6 → No 28 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:** Capitol Land & Minerals Inc → No 28 Mine; 1973-01-01 to 1976-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Capitol Land & Minerals Inc → No 28 Mine; 1973-01-01 to 1976-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Capitol Land & Minerals Inc → Capitol Land & Minerals Inc; 1973-01-01 to 1976-08-31; source msha-controller-operator-history
- **controller_controls_mine:** United  Company → No 28 Mine; 1973-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Wellmore Coal Corp No 6 → No 28 Mine; 1976-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United  Company → Wellmore Coal Corp No 6; 1976-09-01 to current/open; source msha-controller-operator-history