# Relationship history for MSHA mine 4002167

Current hierarchy: **Keller John E → Carbonex Coal Company Inc → Carbonex Tipple No 1**

- 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:** Penta Mining Company Inc → Carbonex Tipple No 1; 1976-12-01 to 1977-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Penta Corp → Carbonex Tipple No 1; 1976-12-01 to 1977-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Penta Corp → Penta Mining Company Inc; 1976-12-01 to 1977-03-31; source msha-controller-operator-history
- **operator_operates_mine:** National Coal Resources Of Dayton → Carbonex Tipple No 1; 1977-04-01 to 1979-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Katz Melvin--Robert Alexander & Gary Long → Carbonex Tipple No 1; 1977-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Katz Melvin--Robert Alexander & Gary Long → National Coal Resources Of Dayton; 1977-04-01 to 1979-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Carbonex Coal Company Inc → Carbonex Tipple No 1; 1979-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Keller John E → Carbonex Tipple No 1; 1979-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Keller John E → Carbonex Coal Company Inc; 1979-09-01 to current/open; source msha-controller-operator-history