# Relationship history for MSHA mine 1506810

Current hierarchy: **Ibex Inc → Kentucky Gem Coal Company-A Joint Venture → Laurel County #1 Surface**

- 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:** Thornberry Rennie - Earl Et Al → Laurel County #1 Surface; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky Gem Coal Company Inc → Laurel County #1 Surface; 1973-10-01 to 1976-10-31; source msha-controller-operator-history
- **controller_controls_operator:** Thornberry Rennie - Earl Et Al → Kentucky Gem Coal Company Inc; 1973-10-01 to 1976-10-31; source msha-controller-operator-history
- **controller_controls_mine:** Ibex Inc Et Al → Laurel County #1 Surface; 1976-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky Gem Coal Company-A Joint Venture → Laurel County #1 Surface; 1976-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ibex Inc Et Al → Kentucky Gem Coal Company-A Joint Venture; 1976-11-01 to current/open; source msha-controller-operator-history