# Relationship history for MSHA mine 1511390

Current hierarchy: **Donald Ray  Tackett → Jen-Nan-Mer Coal Corp → 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:** Denzil R  Hall → No 1; 1977-10-01 to 1987-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Douglas Coal Corp → No 1; 1978-05-01 to 1987-06-15; source msha-controller-operator-history
- **controller_controls_operator:** Denzil R  Hall → Douglas Coal Corp; 1978-05-01 to 1987-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Jen-Nan-Mer Coal Corp → No 1; 1987-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Donald Ray  Tackett → No 1; 1987-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donald Ray  Tackett → Jen-Nan-Mer Coal Corp; 1987-06-16 to current/open; source msha-controller-operator-history