# Relationship history for MSHA mine 1518223

Current hierarchy: **Progress Energy Inc → Kentucky May Coal Co.,Inc. → Solid Energy L L C**

- 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 → Solid Energy L L C; 1989-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky May Coal Company Inc → Solid Energy L L C; 1999-11-01 to 2000-11-29; source msha-controller-operator-history
- **controller_controls_operator:** Florida Progress Corporation → Kentucky May Coal Company Inc; 1999-11-01 to 2000-11-29; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky May Coal Co.,Inc. → Solid Energy L L C; 2000-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Progress Energy Inc → Solid Energy L L C; 2000-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Progress Energy Inc → Kentucky May Coal Co.,Inc.; 2000-11-30 to current/open; source msha-controller-operator-history