# Relationship history for MSHA mine 1517387

Current hierarchy: **Florida Progress Corporation → Kentucky May Mining → Vi-4**

- 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:** Florida Progress Corporation → Vi-4; 1989-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky May Coal Company Inc → Vi-4; 1993-04-01 to 1993-06-14; source msha-controller-operator-history
- **controller_controls_operator:** Florida Progress Corporation → Kentucky May Coal Company Inc; 1993-04-01 to 1993-06-14; source msha-controller-operator-history
- **operator_operates_mine:** Cd Enterprise Inc → Vi-4; 1993-06-15 to 1994-08-15; source msha-controller-operator-history
- **controller_controls_mine:** Charles  Hunt → Vi-4; 1993-06-15 to 1994-08-15; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Hunt → Cd Enterprise Inc; 1993-06-15 to 1994-08-15; source msha-controller-operator-history
- **operator_operates_mine:** Two Way Coal Company Inc → Vi-4; 1994-08-16 to 1995-12-26; source msha-controller-operator-history
- **controller_controls_mine:** Barbieri Augusto → Vi-4; 1994-08-16 to 1995-12-26; source msha-controller-operator-history
- **controller_controls_operator:** Barbieri Augusto → Two Way Coal Company Inc; 1994-08-16 to 1995-12-26; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky May Mining → Vi-4; 1995-12-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Florida Progress Corporation → Vi-4; 2000-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Florida Progress Corporation → Kentucky May Mining; 2000-11-30 to current/open; source msha-controller-operator-history