# Relationship history for MSHA mine 1201076

Current hierarchy: **P H & T Realty Corp → B & M Coal Corp → B & M Strip**

- 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:** Three States Coal Corp → B & M Strip; 1950-01-01 to 1974-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Three States Coal Corp → B & M Strip; 1950-01-01 to 1974-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Three States Coal Corp → Three States Coal Corp; 1950-01-01 to 1974-01-31; source msha-controller-operator-history
- **operator_operates_mine:** B & M Coal Corp → B & M Strip; 1974-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** P H & T Realty Corp → B & M Strip; 1974-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** P H & T Realty Corp → B & M Coal Corp; 1974-02-01 to current/open; source msha-controller-operator-history