# Relationship history for MSHA mine 4002998

Current hierarchy: **Lexington Coal Company LLC → LCC Tennessee LLC → Pine Ridge East**

- 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:** Cyprus Amax Minerals Company → Pine Ridge East; 1987-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Skyline Coal Company → Pine Ridge East; 1988-11-01 to 2003-05-18; source msha-controller-operator-history
- **controller_controls_operator:** Cyprus Amax Minerals Company → Skyline Coal Company; 1988-11-01 to 2003-05-18; source msha-controller-operator-history
- **controller_controls_mine:** Horizon Natural Resources Incorporated → Pine Ridge East; 1998-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Skyline Coal Company → Pine Ridge East; 2003-05-19 to 2005-01-09; source msha-controller-operator-history
- **controller_controls_operator:** Horizon Natural Resources Incorporated → Skyline Coal Company; 2003-05-19 to 2005-01-09; source msha-controller-operator-history
- **controller_controls_mine:** Lexington Coal Company LLC → Pine Ridge East; 2004-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** LCC Tennessee LLC → Pine Ridge East; 2005-01-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lexington Coal Company LLC → LCC Tennessee LLC; 2005-01-10 to current/open; source msha-controller-operator-history