# Relationship history for MSHA mine 1507752

Current hierarchy: **Nichols Mark → Cherokee Processing Inc → Thornton Tipple**

- 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:** Upper Elkhorn Coal Company Inc → Thornton Tipple; 1974-01-01 to 1978-06-07; source msha-controller-operator-history
- **controller_controls_mine:** Johnson William H → Thornton Tipple; 1974-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnson William H → Upper Elkhorn Coal Company Inc; 1974-01-01 to 1978-06-07; source msha-controller-operator-history
- **operator_operates_mine:** Vision Coal Company Inc → Thornton Tipple; 1978-06-08 to 1981-09-20; source msha-controller-operator-history
- **controller_controls_mine:** Caudill James M Jr → Thornton Tipple; 1978-06-08 to 1981-09-20; source msha-controller-operator-history
- **controller_controls_operator:** Caudill James M Jr → Vision Coal Company Inc; 1978-06-08 to 1981-09-20; source msha-controller-operator-history
- **operator_operates_mine:** Upper Elkhorn Coal Company → Thornton Tipple; 1981-09-21 to 1981-12-29; source msha-controller-operator-history
- **controller_controls_mine:** Club Marshall → Thornton Tipple; 1981-09-21 to 1981-12-29; source msha-controller-operator-history
- **controller_controls_operator:** Club Marshall → Upper Elkhorn Coal Company; 1981-09-21 to 1981-12-29; source msha-controller-operator-history
- **operator_operates_mine:** Curtis Coal → Thornton Tipple; 1981-12-30 to 1982-07-12; source msha-controller-operator-history
- **controller_controls_mine:** Scarborough James C & Donald King → Thornton Tipple; 1981-12-30 to 1982-07-12; source msha-controller-operator-history
- **controller_controls_operator:** Scarborough James C & Donald King → Curtis Coal; 1981-12-30 to 1982-07-12; source msha-controller-operator-history
- **operator_operates_mine:** Cavalier Processing Inc → Thornton Tipple; 1982-07-13 to 1983-03-28; source msha-controller-operator-history
- **controller_controls_mine:** Sanders Kedrick → Thornton Tipple; 1982-07-13 to 1983-03-28; source msha-controller-operator-history
- **controller_controls_operator:** Sanders Kedrick → Cavalier Processing Inc; 1982-07-13 to 1983-03-28; source msha-controller-operator-history
- **operator_operates_mine:** Red Bird Coal Corp → Thornton Tipple; 1983-03-29 to 1983-06-08; source msha-controller-operator-history
- **controller_controls_mine:** Crase Tilden Jr → Thornton Tipple; 1983-03-29 to 1983-06-08; source msha-controller-operator-history
- **controller_controls_operator:** Crase Tilden Jr → Red Bird Coal Corp; 1983-03-29 to 1983-06-08; source msha-controller-operator-history
- **operator_operates_mine:** Palomino Coal Company Inc → Thornton Tipple; 1983-06-09 to 1984-11-20; source msha-controller-operator-history
- **controller_controls_mine:** Caudill David N → Thornton Tipple; 1983-06-09 to 1984-11-20; source msha-controller-operator-history
- **controller_controls_operator:** Caudill David N → Palomino Coal Company Inc; 1983-06-09 to 1984-11-20; source msha-controller-operator-history
- **operator_operates_mine:** Cherokee Processing Inc → Thornton Tipple; 1984-11-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Nichols Mark → Thornton Tipple; 1984-11-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nichols Mark → Cherokee Processing Inc; 1984-11-21 to current/open; source msha-controller-operator-history