# Relationship history for MSHA mine 1506998

Current hierarchy: **Williams Companies Inc → Leeco Inc → Joann Tipple; No 4 Mine**

- 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

- **controller_controls_mine:** Thornberry Rennie - Earl Et Al → Joann Tipple; No 4 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky Gem Coal Company Inc → Joann Tipple; No 4 Mine; 1974-01-01 to 1976-12-10; source msha-controller-operator-history
- **controller_controls_operator:** Thornberry Rennie - Earl Et Al → Kentucky Gem Coal Company Inc; 1974-01-01 to 1976-12-10; source msha-controller-operator-history
- **controller_controls_mine:** Ibex Inc Et Al → Joann Tipple; No 4 Mine; 1976-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky Gem Coal Company-A Joint Venture → Joann Tipple; No 4 Mine; 1976-12-11 to 1981-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Ibex Inc Et Al → Kentucky Gem Coal Company-A Joint Venture; 1976-12-11 to 1981-08-03; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky Gem Coal Company Inc → Joann Tipple; No 4 Mine; 1981-08-04 to 1983-11-20; source msha-controller-operator-history
- **controller_controls_operator:** Thornberry Rennie - Earl Et Al → Kentucky Gem Coal Company Inc; 1981-08-04 to 1983-11-20; source msha-controller-operator-history
- **controller_controls_mine:** Kaneb Services Inc → Joann Tipple; No 4 Mine; 1982-06-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bituminous-Laurel Mining Inc → Joann Tipple; No 4 Mine; 1983-11-21 to 1985-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Kaneb Services Inc → Bituminous-Laurel Mining Inc; 1983-11-21 to 1985-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Williams Companies Inc → Joann Tipple; No 4 Mine; 1985-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Leeco Inc → Joann Tipple; No 4 Mine; 1986-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Williams Companies Inc → Leeco Inc; 1986-01-01 to current/open; source msha-controller-operator-history