# Relationship history for MSHA mine 1505106

Current hierarchy: **Lexington Coal Holdings, Inc → Lexington Coal Company, LLC → Preparation Plant**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Martin County Coal LLC → Preparation Plant; 1950-01-01 to 2017-10-22; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → Preparation Plant; 1975-05-28 to 2011-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Martin County Coal LLC; 1975-05-28 to 2011-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Natural Resources, Inc. → Preparation Plant; 2011-06-01 to 2016-07-25; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Natural Resources, Inc. → Martin County Coal LLC; 2011-06-01 to 2016-07-25; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Natural Resources Holdings, Inc → Preparation Plant; 2016-07-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Natural Resources Holdings, Inc → Martin County Coal LLC; 2016-07-26 to 2017-10-22; source msha-controller-operator-history
- **operator_operates_mine:** Lexington Coal Company, LLC → Preparation Plant; 2017-10-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lexington Coal Holdings, Inc → Preparation Plant; 2017-10-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lexington Coal Holdings, Inc → Lexington Coal Company, LLC; 2017-10-23 to current/open; source msha-controller-operator-history