# Relationship history for MSHA mine 4403657

Current hierarchy: **B S & A Coal Co → B S & A Coal Co → No 3 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

- **controller_controls_mine:** United  Company → No 3 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** B S & A Coal Co → No 3 Mine; 1973-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Wellmore Coal Corp → No 3 Mine; 1974-01-01 to 1974-06-30; source msha-controller-operator-history
- **controller_controls_operator:** United  Company → Wellmore Coal Corp; 1974-01-01 to 1974-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Safety Coal Corp → No 3 Mine; 1974-07-01 to 1975-05-30; source msha-controller-operator-history
- **controller_controls_mine:** Sweeney Melvin → No 3 Mine; 1974-07-01 to 1975-05-30; source msha-controller-operator-history
- **controller_controls_operator:** Sweeney Melvin → Safety Coal Corp; 1974-07-01 to 1975-05-30; source msha-controller-operator-history
- **operator_operates_mine:** B S & A Coal Co → No 3 Mine; 1975-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** B S & A Coal Co → B S & A Coal Co; 1975-06-01 to current/open; source msha-controller-operator-history