# Relationship history for MSHA mine 3605648

Current hierarchy: **Taylor Leon & Harold Hubler → H & T Coal Company → Strip Mine #1**

- 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:** G & R Stone & Coal Company → Strip Mine #1; 1975-07-01 to 1976-02-12; source msha-controller-operator-history
- **controller_controls_mine:** G & R Stone & Coal Co → Strip Mine #1; 1975-07-01 to 1976-02-12; source msha-controller-operator-history
- **controller_controls_operator:** G & R Stone & Coal Co → G & R Stone & Coal Company; 1975-07-01 to 1976-02-12; source msha-controller-operator-history
- **operator_operates_mine:** H & T Coal Company → Strip Mine #1; 1976-02-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Taylor Leon & Harold Hubler → Strip Mine #1; 1976-02-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Taylor Leon & Harold Hubler → H & T Coal Company; 1976-02-13 to current/open; source msha-controller-operator-history