# Relationship history for MSHA mine 1515391

Current hierarchy: **Medlin Fred E → Allen Clay Coal Inc → 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

- **controller_controls_mine:** Medlin Fred E → No 1; 1977-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roy Donald  Lewis et al → No 1; 1979-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Denham & Lewis Corp → No 1; 1985-10-01 to 1989-04-03; source msha-controller-operator-history
- **controller_controls_operator:** Roy Donald  Lewis et al → Denham & Lewis Corp; 1985-10-01 to 1989-04-03; source msha-controller-operator-history
- **controller_controls_operator:** Charles R  Denham et al → Denham & Lewis Corp; 1985-10-01 to 1989-04-03; source msha-controller-operator-history
- **operator_operates_mine:** Allen Clay Coal Inc → No 1; 1989-04-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Medlin Fred E → Allen Clay Coal Inc; 1989-04-04 to current/open; source msha-controller-operator-history