# Relationship history for MSHA mine 1515265

Current hierarchy: **Potter David W & Michael L → Kentucky-Virginia Coal Corp → No 9 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:** Potter David W & Michael L → No 9 Surface; 1981-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky-Virginia Coal Corp → No 9 Surface; 1985-06-01 to 1986-04-15; source msha-controller-operator-history
- **controller_controls_operator:** Potter David W & Michael L → Kentucky-Virginia Coal Corp; 1985-06-01 to 1986-04-15; source msha-controller-operator-history
- **controller_controls_mine:** Steele Carlos P Et Al → No 9 Surface; 1985-07-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Shelma Mining Company Inc → No 9 Surface; 1986-04-16 to 1986-07-30; source msha-controller-operator-history
- **controller_controls_operator:** Steele Carlos P Et Al → Shelma Mining Company Inc; 1986-04-16 to 1986-07-30; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky-Virginia Coal Corp → No 9 Surface; 1986-07-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Potter David W & Michael L → Kentucky-Virginia Coal Corp; 1986-07-31 to current/open; source msha-controller-operator-history