# Relationship history for MSHA mine 4601723

Current hierarchy: **William G  Skewes → Ridge Land Company Inc → No 6 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:** William G  Skewes → No 6 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Church & Mullins Corp → No 6 Mine; 1950-01-01 to 1977-11-03; source msha-controller-operator-history
- **controller_controls_mine:** Church & Mullins Corp → No 6 Mine; 1950-01-01 to 1977-11-03; source msha-controller-operator-history
- **controller_controls_operator:** Church & Mullins Corp → Church & Mullins Corp; 1950-01-01 to 1977-11-03; source msha-controller-operator-history
- **operator_operates_mine:** S & A Coal Company Inc → No 6 Mine; 1977-11-04 to 1979-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Dillon William A → No 6 Mine; 1977-11-04 to 1979-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Dillon William A → S & A Coal Company Inc; 1977-11-04 to 1979-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Ridge Land Company Inc → No 6 Mine; 1979-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William G  Skewes → Ridge Land Company Inc; 1979-05-01 to current/open; source msha-controller-operator-history